clinical progress transposition pulmonary veins · clinical progress transposition of the...

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CLINICAL PROGRESS Transposition of the Pulmonary Veins By WARREN G. GUNTHEROTH, M.D., ALEXANDER S. NADAS, M.D., AND ROBERT E. GROSS, M.D. PULMONARY veins entering the right atrium or its tributaries constitute the entity of transposition of the pulmonary veins. The transposition may be complete, when all the veins enter the right heart, or incomplete, when only some of the pulmonary veins drain anomalously. We are reviewing our experiences with total and partial anoma- lies of pulmonary venous drainage because of the increasing surgical interest in the prob- lem, and because we feel that the clinical profile to be presented is sufficiently charac- teristic to enable the cardiologist to make the diagnosis with relative ease in most instances. MATERIALS AND METHODS Thirty-one patients with uncomplicated transpo- sition of the pulmonary veins admitted to the Chil- dren's Medical Center in Boston, were studied clinically, with complete history, physical exam- inations, x-ray and fluoroseopie examinations, and 12-lead electrocardiograms. The diagnosis was confirmed in each instance by cardiac catheteriza- tion, surgery, or autopsy. The technics used in our cardiac catheterization laboratory have been described in previous publications.' COMPLETE TRANSPOSITION OF THE PULMONARY VEINS Definition Drainage of the entire systemic and pulmo- nary return into the right heart is the major abnormality in complete transposition of the pulmonary veins. An atrial septal defect or a patent foramen ovale is necessary for any systemic output, and is therefore an inte- gral part of the lesion. Following Brody's From the Department of Pediatrics and Surgery, Harvard Medical School and Sharon Cardiovascular Unit of the Children 's Medical Center, Boston, Mass. These investigations have been supported by grants from the American Heart Association and from the National Heart Institute of the U. S. Department of Health, Education and Welfare. Presented, in part, at the Second World Congress of Cardiology, Washington, D.C., September 12, 1954. 117 original classification,2 we have not consid- ered a patent ductus arteriosus as a compli- eating anomaly, but have excluded cases with other major cardiovascular abnormalities from discussion here. Incidence Complete transposition of the pulmonary veins is a rare condition. Maude Abbott3 found only 4 cases (including 3 complicated ones) in her series of 1,000 autopsies of con- genital heart disease. Brody, in a classical monograph in 1942,2 reviewed 38 cases from the literature; 14 of these were associated with other major cardiac anomalies. Up to the present time there have been 159 uncom- plicated cases reported.41 Embryology The developmental anomaly producing this malformation probably occurs in the seventh week of gestation12 and represents either complete failure of absorption of the com- mon pulmonary vein into the dorsal wall of the sinus venosus, or abnormal placement of the ostia of this vein in relation to the sep- tum, which divides the sinus venosus into the right and left atria. In the first instance, the pulmonary veins drain via a persistent, enlarged primitive connection between the pulmonary and systemic circulations. These connections have been demonstrated in nor- mal adults with postmortem injections by Zuckerkandl in 1881, and are reminiscent of the development of the entire pulmonary cir- culation from part of the presplanchnic plexus.'3 Anatomic Considerations The site at which the pulmonary veins connect to the systemic circulation has been used as the basis of anatomic classification of complete transposition of the pulmonary veins by Darling, Rothney, and Craig.4 This Circulation, Volume XVIII, July 1958

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Page 1: CLINICAL PROGRESS Transposition Pulmonary Veins · CLINICAL PROGRESS Transposition of the PulmonaryVeins By WARREN G. GUNTHEROTH, M.D., ALEXANDER S. NADAS, M.D., AND ROBERT E. GROSS,

CLINICAL PROGRESS

Transposition of the Pulmonary VeinsBy WARREN G. GUNTHEROTH, M.D., ALEXANDER S. NADAS, M.D., AND ROBERT E. GROSS, M.D.

PULMONARY veins entering the rightatrium or its tributaries constitute the

entity of transposition of the pulmonaryveins. The transposition may be complete,when all the veins enter the right heart, orincomplete, when only some of the pulmonaryveins drain anomalously. We are reviewingour experiences with total and partial anoma-lies of pulmonary venous drainage because ofthe increasing surgical interest in the prob-lem, and because we feel that the clinicalprofile to be presented is sufficiently charac-teristic to enable the cardiologist to make thediagnosis with relative ease in most instances.

MATERIALS AND METHODSThirty-one patients with uncomplicated transpo-

sition of the pulmonary veins admitted to the Chil-dren's Medical Center in Boston, were studiedclinically, with complete history, physical exam-inations, x-ray and fluoroseopie examinations, and12-lead electrocardiograms. The diagnosis wasconfirmed in each instance by cardiac catheteriza-tion, surgery, or autopsy. The technics used inour cardiac catheterization laboratory have beendescribed in previous publications.'

COMPLETE TRANSPOSITION OF THEPULMONARY VEINS

DefinitionDrainage of the entire systemic and pulmo-

nary return into the right heart is the majorabnormality in complete transposition of thepulmonary veins. An atrial septal defector a patent foramen ovale is necessary forany systemic output, and is therefore an inte-gral part of the lesion. Following Brody's

From the Department of Pediatrics and Surgery,Harvard Medical School and Sharon CardiovascularUnit of the Children 's Medical Center, Boston, Mass.

These investigations have been supported by grantsfrom the American Heart Association and from theNational Heart Institute of the U. S. Department ofHealth, Education and Welfare.

Presented, in part, at the Second World Congressof Cardiology, Washington, D.C., September 12, 1954.

117

original classification,2 we have not consid-ered a patent ductus arteriosus as a compli-eating anomaly, but have excluded cases withother major cardiovascular abnormalitiesfrom discussion here.

IncidenceComplete transposition of the pulmonary

veins is a rare condition. Maude Abbott3found only 4 cases (including 3 complicatedones) in her series of 1,000 autopsies of con-genital heart disease. Brody, in a classicalmonograph in 1942,2 reviewed 38 cases fromthe literature; 14 of these were associatedwith other major cardiac anomalies. Up tothe present time there have been 159 uncom-plicated cases reported.41

EmbryologyThe developmental anomaly producing this

malformation probably occurs in the seventhweek of gestation12 and represents eithercomplete failure of absorption of the com-mon pulmonary vein into the dorsal wall ofthe sinus venosus, or abnormal placement ofthe ostia of this vein in relation to the sep-tum, which divides the sinus venosus into theright and left atria. In the first instance,the pulmonary veins drain via a persistent,enlarged primitive connection between thepulmonary and systemic circulations. Theseconnections have been demonstrated in nor-mal adults with postmortem injections byZuckerkandl in 1881, and are reminiscent ofthe development of the entire pulmonary cir-culation from part of the presplanchnicplexus.'3Anatomic ConsiderationsThe site at which the pulmonary veins

connect to the systemic circulation has beenused as the basis of anatomic classification ofcomplete transposition of the pulmonaryveins by Darling, Rothney, and Craig.4 This

Circulation, Volume XVIII, July 1958

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GUNTHEROTH, NADAS, AND GROSS

TABLE l.-Classification' and Incidence of Typesof Complete Transposition of the Pulmonary Veins,Based on 159 Uncomplicated Cases

Level of drainage Type Percentage

Supracardiac 1A left superior vena cava 48%) 57%1B right superior vera cava 9%J

Cardiac HA coronary sinus 14%) 32%JIB right atrium 18%f

Infracardiac III portal vein or ductusvenosus 9%

Mixed levels IV 2%

classification has considerable interest forprognostic and surgical reasons. We haveclassified 159 uncomplicated cases from theliterature according to this method (table 1).

Certain other anatomic considerations areof surgical importance. The anomalous veins,with great consistency, form a relatively largecommon channel prior to joining the system-ic veins except when they join the rightatrium directly. In the latter group approxi-mately one third join the right atrium by mul-

tiple channels, but more than one half emptyinto an ante-chamber, described by Kirchmairand Blum,14 which is, from the surgeon 'spoint of view, conveniently located on theposterosuperior wall of the right atrium, tothe left of the superior vena cava and inferiorvena cava, and superior to the coronary sinusand the atrioventricular conduction system.

Finally the entire left heart is relativelyhypoplastic; and, as Keith pointed out,15 thecircumference of the common pulmonaryvein frequently exceeds that of the waist ofthe left atrial appendage, a formidable dis-advantage in attempting surgical correctionof this condition.Physiology

Complete transposition of the pulmonaryveins is a serious anomaly, profoundly alter-ing the normal circulatory pattern. In thisanomaly, the right atrium receives the entiresystemic and pulmonary venous return, andsupplies the left heart through a patent for-amen ovale or an atrial septal defect. As inother types of congenital heart disease with

complete mixing, the systemic arterial satu-ration will depend entirely on the ratio ofpulmonary to systemic flow, at a given oxy-gen consumption.*

However, as various investigators havepointed out,8' 16 mixing at the atrial level maynot be complete. The systemic arterial satu-ration is often slightly less than that of thepulmonary artery; this difference is attrib-uted by the Mayo group16 to preferentialshunting of the inferior vena caval bloodthrough the interatrial communication. Thistype of preferential shunting has a precedentin fetal circulation.'7 18 Occasionally, thepulmonary artery oxygen saturation is lowerthan that of the systemic artery, perhaps dueto preferential flow of blood from the coro-nary sinus or superior vena cava across thetricuspid valve into the right ventricle.Although the resting systemic output of

these patients is usually normal or onlyslightly reduced, increasing output 3 or 4-fold (as with moderately severe exercise)would require a corresponding increase inpulmonary blood flow, if the systemic arteri-al saturation were maintained. With a rest-ing heart rate greater than average and aright ventricular stroke volume 2 to 3 timesthat of the left, the required pulmonary bloodflow would be almost impossible to achieve.Evidence of the resultant limitation of car-diac output is the almost universal history ofeasy fatigability and the autopsy finding ofa hypoplastic left heart.

Although the majority of patients withcomplete transposition of the pulmonary veinsdie in infancy or early childhood, a few sur-vive into adulthood with remarkably fewsymptoms. How this group maintains a com-pensated cardiovascular system in the faceof such profound disorder has never been ex-plained satisfactorily.

Presentation of DataClinical MaterialTwenty patients with uncomplicated, com-

*DowlO and Burchell1' have recently derived formu-lae to predict the systemic arterial saturation on thebasis of these parameters.

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TRANSPOSITION OF THE PULMONARY VEINS

plete transposition of the pulmonary veinshave been studied at our hospital in the years1950 to 1956. Because the clinical picturemay vary considerably, depending upon thelevel at which the pulmonary veins drain, wehave used Darling, Rothney, and Craig 'sclassification4 to subdivide our material. Thepulmonary veins drained into an ascendingleft superior vena cava in 9 of our cases, intothe coronary sinus in 4, into the right atriumin 3, and below the diaphragm in 4 patients.The clinical diagnosis was confirmed by

operation or autopsy in 15 patients,* and bycardiac catheterization only in the remaining5.Our patients ranged in age from 10 days to

19 years with an average age of 5 years; 10of them were less than 6 months old. Thegroup draining below the diaphragm wasunique in that none survived more than 7weeks and 2 survived only 10 days. None ofthe others died at less than 7 weeks of age.The incidence of males in the entire group

was the same as females; in the infradia-phragmatic group, all 4 patients were males.The interatrial communication in the 12

autopsied cases was a patent foramen ovalein 10 instances, and an atrial septal defectin 2 (1 ostium primum and 1 ostium secun-dum). The size of the interatrial opening inour autopsied cases had no correlation withlongevity or degree of unsaturation whentaken in relation to the circumference of themitral valve (table 2). Previous reportsattributing prognostic importance to the sizeof this opening failed to correlate it with theover-all heart size.

Similarly, the presence and size of a patentductus arteriosus had no correlation withlongevity in our patients. Eight of the 12autopsied cases had patent ducti, probe-patent in 5, moderate sized in 1, and largein 2.Mild pulmonary vascular obstruction was

found in 5 autopsied patients, and moderateobstruction in 4. Although the 3 patients in

*The autopsy material of the Children 's MedicalCenter has been presented in detail in an earlierpublication.'

TABLE 2.-Correlation of Age of Death with Sizeof Interatrial Communication and Patency of DuctusArteriosus

Age

10 days10 days6 weeks7 weeks2 months2 months2 months3 months4 months*12A yrs.*12, yrs.*42A yrs.

Type

IIIIIIIIIIII

IIII

IIAIIB

II

De-greecya-nosis

3+1+1+1+2+1+2+1+1+1+1+2+

Circum-ferenceASD orPFO(cm.)

2.82.54.75.51.51.5.6

1.53.95.53.12.4

Circum-ferencemitralvalve(cm.)

3.03.03.03.53.03.73.53.54.05.55.05.0

Ductus

LargeClosedProbe patentClosedLargeProbe patentClosedProbe patentClosedProbe patentModerate sizeProbe patent

* Operative deaths.ASD =atrial septal defect.PFO = patent foramen ovale.

the autopsied group surviving the longest hadno obstructive changes, there was no correla-tion, in the other 9 patients, of age at deathwith severity of medial hypertrophy and in-timal hyperplasia of the pulmonary arteries.history

There was no family history of congenitalheart disease in any of our 20 patients. In4 instances, however, there were difficultiesin the first trimester of pregnancy; 2 "viral"respiratory infections, 1 threatened abortion,and 1 instance of severe malnutrition.The symptoms presented by these patients

were nonspecific; mild cyanosis, fatigability,dyspnea, and increased frequency and severi-ty of respiratory infections were almost uni-versal complaints. The onset of cyanosisvaried from birth to 12 years of age. Squat-ting and "anoxic" spells were relatively un-common, occurring in one fifth of the pa-tients.

Physical ExaminationThe findings at physical examination were

more specific, in certain instances, than werethe histories of these patients. The patientswere small and undernourished in general;over two thirds of them fell below the twenty-fifth percentile on our height and weightcharts.20

---

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GUNTHEROTH, NADAS, AND GROSS

m

Ia

'V

l lit

1

21

4X a

Uf c-

a

IIj EI'll'

2

I, S

11

JL A11__1 .. _.._... _ _ . .. _

FIG. 1. Phonocardiogram in complete transpositionof the pulmonary veins, illustrating the multipleheart sounds, and systolic and presystolic murmurs.

The patients without exception were atleast mildly eyanotic; more marked cyanosiswas found in the group with congestive fail-ure, and in the group with drainage belowthe diaphragm. Only one half of the pa-

tients demonstrated clubbing.The resting pulse rate was above normal

range in 14 patients, including 11 in conges-

tive failure. The blood pressure and pulsepressure did not vary significantly from thenormal.

Congestive failure was diagnosed in 16 of20 cases, manifested in every instance by a

large liver, but in only half by distendedveins or peripheral edema. Hepatomegalywas particularly marked in the patients withdrainage below the diaphragm. The pres-

ence of pulmonary congestion was difficultto ascertain by physical examination alone,because of the high incidence of concomitantrespiratory infections. In 1 case with drain-age into the portal vein, pulmonary edemawas diagnosed clinically and radiologicallyand was confirmed at autopsy.

Left chest prominence was found in 8 ofthe older children with very large hearts. Inevery instance, the cardiac impulse was maxi-mal at the lower left sternal border.On auscultation, the first sound was loud

at the apex or lower left sternal border in 6cases; the second sound was increased in in-tensity at the pulmonic area in one half thecases, and within normal limits in the remain-der. Splitting of the second sound was ob-served in all but 2 patients. An unusuallyprominent third sound was present in 13 of

20 patients, and a fourth, or atrial sound wasaudible in 5 patients.

Systolic murmurs were heard in all except2 patients, who were 6 and 8 weeks of agerespectively. The systolic murmurs wereusually soft and heard best at the left sternalborder, the majority being maximal at thefourth interspace, but only slightly fewer atthe second to third interspaces. This typeof soft systolic murmur has been attributedto tricuspid insufficiency by Keith.15 A pal-pable systolic thrill and rough, loud murmurwere noted in 5 patients; 4 of these werefound to have a pressure gradient across thepulmonic valve, and in the fifth, catheterizedfrom the femoral vein, the pulmonary arterywas not entered.

Eleven patients had low frequency mid-diastolic murmurs at the apex or lower leftsternal border. This type of murmur, fre-quently found in patients with a large ven-tricular stroke volume,21 was observed inevery patient over 6 months of age. A pre-systolic murmur of medium to high frequencyat the lower left sternal border, synchronouswith atrial systole, was heard in 6 instances(fig. 1). This murmur was usually diamondshaped on the phonocardiogram, and was ac-companied by a fourth sound, Examples ofthis murmur were heard in all types exceptthe group with subdiaphragmatic drainage;within the framework of the other clinicalfeatures, we consider its presence to be prac-tically pathognomonic.

Keith and associates15 have described apronounced, although transient, venous humat the upper left sternal border in 4 patientswith drainage of the pulmonary veins intoa remnant of the left superior vena cava. Wewere able to find this type of murmur in only1 case, and then the murmur was maximal atthe right sternal border.

ElectrocardiogramsThe electrocardiograms of patients with

complete transposition of the pulmonaryveins reflect the pathologic physiology andanatomy, with evidence of right-sided hyper-trophy and dilatation. Right axis deviation,right ventricular hypertrophy, and incom-

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1 A_Mr

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TRANSPOSITION OF TIlE IPULMONARY VEINS

Lead I II III aVR aVL

Lead V4R V1 V2 V4 V5 V6

FIG. 0. Representaltive electi-oattd(liogr',llul ill complete transposition of the pulmonary Veins,illustrating marked right ventricular hlvperti ol)lly, ilCO IIIletet ight bundle -i.auch llock, P)pulmonale, and T-wanve changes.

plete right bundle-branich block were present,iii ev(er patient (fig. 2). The de(greI'(e of righ,.ltVetitrieUlar hypIertrophy il this group of pa-

tieiits is miarked and has bect flote(I by others.Altlhough Keitlh and co-+workers' cneIphasizedthe frequency of a qR pattern iii the rightprecordial lea(s,, we foumd this )atteril inOnly O c(ases; and in tlhese there wvas evidencesuirestiiio that the pattern was, aIctually anrsR' pattern, with an- isoelectric r. A morefrequent finding in our series wvas completereversal of the adult R/SS progressioni in theprecordial lead, i.e., qIR, rsR,' or Rs patternin the right precordial leads, and ctrS in theleft precordials, indicatiiig marked right ven-tricular hypertrophy.'' Sixteen of our pa-tients demonstrated this phenomenon, andthe exceptions were all in the older age group.Right ventricular intriilsicoi( deflcectioi

(lelay correlated closely with age, but was

abnormally delayed in 1.5 eases. The groul)drainiimg below the diaplragm wvere an- excel)-tion, with 3 out of 4 having a normal activa-tioli timie, wich may 1)b' correlate(d wsith timrelatively small size of their hearts by x-raya41(1 )ostmortell examniat ion.

T-wave abnormalities o('curred in. 13 cases.

A additional 3 cases; lhid T-wave bl)uiormalia-ties, possibly due to (digitalis.

FiG. 3. Radiogranm of patient with drainage of alluluoary +veins into ani aiscending left superior vena

c.ava illustr.atinig tle figure eight pattern.

A tall, peaked P wave, or P pulmonale, washlrcsellt in 13 of 20 cases. In the 4 patientsw-ith drainage below the diaphragm, therew\r o11 instances of P pulmolnale.K -l'u~ysThe radiograins of certain tylpes of com-

plete trailsp)ositioii of the pulmoinary veinsare practically pathlognomonic, as for exam-

12M1

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GUNTHEROTH, NADAS, AND GROSS

FIG. 4. Radiograms of 4 patients with drainage of all pulmonary veins into the portal vein,illustrating a small heart in the presence of intense pulmonary congestion and hepatomegaly.

ple the figure-eight pattern described by Snel-len and Albers23 (fig. 3). The upper half ofthe 8 is formed by a remnant of the left su-perior vena cava, as it ascends to join the leftinnominate, and the right superior vena cavaemptying caudally into the right atrium.This venous structure will pulsate, if at all, inan " acvp" pattern, whereas the pulmonaryartery will expand synchronously with ven-tricular systole. The thymus, in the upper,anterior mediastinal area, does not pulsateintrinsically at all. A wide superior medias-tinal pattern also may be produced by atrue, persistent left superior vena cava with-out pulmonary venous anomaly, as it de-

scends to drain into the coronary sinus; thisgroup lacks, however, the rounded upper mar-gin characteristic of the figure-eight, and thepatients are not ordinarily cyanotic. Thefull-blown figure-eight pattern is not usuallyfound in infancy. The youngest patient inour series with this contour was 4 years old,although in every case over the age of 3months, widening of the superior mediasti-num was definite.The group with drainage below the dia-

phragm also presents a pathognomonic roent-genologic picture of moderate to marked pul-monary vascular engorgement and congestionwith a normal-sized heart (fig. 4). There is

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TRANSPOSITION OF THE PULMONARY VEINS

FIG. 5. Radiogram of a patient with drainage of all pulmonary veins into the coronarysinus: Postero-anterior film of chest and lateral view of barium swallow. (Reproduced fromYadas, A. S., Pediatric Cardiology, Philadelphia and London, W. B. Saunders Company,1957, page 518.) *

no other type of cyanotic congenital heartdisease demonstrating this combination, in thepresence of congestive failure. However, thevascular pattern per se is not different fromthat seen in other heart diseases in whichthere is passive congestion, such as mitralstenosis.When drainage occurs at the atrial level,

the radiogram is nonspecific in most instances.Two of 4 cases with pulmonary return intothe coronary sinus had a widened superiormediastinal shadow due to a true left superi-or vena cava, which also drained systemicblood into the coronary sinus. One of thesepatients had a bulge in the posterior aspectof the cardiac shadow, on barium swallow,suggesting by its size and location an en-larged coronary sinus (fig. 5). Another pa-tient with drainage into the coronary sinushad an angular prominence of the upper rightatrial border, directly across from the sinusostium. When the veins drain directly intothe right atrium, the picture is characteristiconly of the basic disorder (fig. 6). The car-diac silhouette produces a box-like shadow,as Gott et al.6 pointed out, but so do mostlesions involving the right side of the heartwith increased pulmonary blood flow.

FIG. 6. Radiogram of a patient with drainage ofall pulmonary veins into the right atrium, illustratinga "box-like" pattern.

Cardiomegaly was present in our 20 pa-tients in every instance except for the 4 caseswith drainage below the diaphragm. In themajority of cases, the enlargement was mod-erate to marked. In the cases where conges-tive failure had not obliterated the character-

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GUNTHEROTII, NADAS, AND GROSS

FiG. 7. Venous angiocardiogram in a patient with drainage of all pulmonary veins intoan ascending left superior vena cava, outlining the supracardiac vascular pattern formedby the left cava, left innominate, and right superior vena cava. (Reproduced from Nadas, A.S., Pediatric Cardiology, Philadelphia and London, W. B. Saunders Company, 1957, page 521.)

istic contour, right ventricular configurationwas uniformly present. Atrial enlargementcould be diagnosed with certainty in 9 pa-tients; there was no demonstrable atrialenlargement in any of the cases draining be-low the diaphragm. The pulmonary arterywas abnormally prominent in over one half,and pulmonary vascular engorgement wasmarked in all. Passive congestion was pres-ent in over half of the children, includingall of those with drainage below the dia-phragm, in whom it was particularly marked."Hilar dance" or intrinsic pulsation of thehilar vessels, was found in 8 of the 20 cases,and its absence was correlated in every in-stance but 1 with an age of less than 6months.Angiocardiograms were performed in only

a small number of our cases (fig. 7). Since a

definitive diagnosis can be made withoutangiocardiographs, the additional risk of thisprocedure is not justified, in our opinion, ex-cept in those cases being considered for car-diac surgery when additional anatomic detailis desired; and then, it should be done by se-lective angiocardiography. By venous angio-cardiography, however, the exact site of unionwas never established, when it was not knownwith certainty prior to the procedure.

Cardiac CatheterizationWTe have catheterized 10 patients with com-

plete transposition of the pulmonary veins,including 4 patients with drainage into thesuperior vena cava, 3 draining into the coro-nary sinus, and 3 into the right atrium,(table 3). None of our 4 cases with drainagebelow the diaphragm was catheterized (none

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TRANSPOSITION OF THE PULMONARY VEINS

TABLE 3.-Data from Cardiac Catheterization of Patients with Complete Transposition ofthe Pulmonary Veins

Patient number 1 2 3 4 5 6 7 8 9 10Type I I I I IIA IIA IIA JIB JIB JIBAge (years) 2 4 15 19 7 10 12 5/12 2 19Rise in 02 at level of mixing (vol. %) 4.8 5.2 3.9 4.6 3.4 4.7 5.1 4.3 4.3 5.5(% saturation) 26 26 21 23 15 25 29 29 27 25

Systemic artery (% saturation) 80 84 93 88 85 87 93 47 88 87Pulmonic artery (% saturation) 82 84 89 87 84 86 92 51 88 87Systemic index (L./min./M.2) 6.6 3.2 6.3 2.9 4.7 3.3 2.6 3.9 5.1 2.3Pulmonic index (L./min./M.2) 6.6 6.7 15 7.5 4.7 5.8 11 2.4 11 10Resistances ratio (Pulm/Systemic) * 1/20 1/7 1/7 * * 1/37 * 1/11 1/32Wedge pressure (mm. Hg) 2t - - - - 12Rt. atrial pressure (mm. Hg) 3 3 6.5 10 3 9 9 15 5 12

* These patients were catheterized from the femoral vein and the pulmonary artery was not entered.t Actual left atrial pressure.$ Probably not representative. This patient's condition deteriorated markedly during the procedure.

survived beyond 7 weeks). The ages of thecatheterized subjects ranged from 6 monthsto 18 years with an average age of 9 years.

Arterial oxygen saturation ranged from 80to 93 per cent with an average of 87 per cent.(This range excludes 1 patient whose condi-tion deteriorated during the procedure, whosesaturation was 47 per cent.) The rise in oxy-gen saturation at the site of union of thesystemic and pulmonary returns, varied from15 to 29 per cent with an average of 25 percent. The resting cardiac output rangedfrom 2.3 to 6.6 L. per minute per M.2 of bodysurface area, with an average of 3.9 (withinnormal limits for resting cardiac index). Pul-monary blood flow, however, ranged from 4.3to 15 L. per minute per M.2, with an averageof 8.7. The average ratio of pulmonary tosystemic flow, thus, was 2.2 to 1. Althoughliterally all of the systemic flow was via aright-to-left shunt at the atrial level, theeffective right-to-left shunt (i.e., the dilutionof oxygenated blood with unsaturated venousreturn) was small relative to the left-to-rightshunt. This ratio, on the average was 1 to 7.*Right atrial pressures were somewhat in-

creased, on the average, although there wasconsiderable spread, 3 to 15 mm. Hg. In 1patient the left atrium was entered and wasfound to have a mean pressure of 1 mm. of

*Systemic flow, in addition to pulmonary flow, isdifficult to estimate with accuracy in these patients,since obtaining a true mixed venous sample isimpossible.

Hg less than the right atrium. Pulmonaryartery wedge or "P.C." pressure was ob-tained in 1 patient and was identical with theright atrial pressure. There was no closecorrelation between the clinical manifesta-tions of failure and the right atrial pressure.For the patients not in congestive failure,there was an interesting inverse relationshipbetween right atrial pressure and left ven-tricular output; the higher the right atrialpressure, the lower the systemic output (fig.8). With patients in failure there was some-what more scatter, but the trend persisted.In the patient with marked deterioration dur-ing the procedure, the highest right atrialpressure was obtained; and the relationshipto cardiac output was considerably out of linewith the other 9 patients. This relationship,although based on a relatively small numberof cases and subject to the serious limitationof calculating outputs, has previously beendescribed by Dow and Dexter24 in patientswith atrial septal defects. Dow and Dextersuggested that peripheral tissue requirementsdetermine left ventricular output, which inturn determines the left atrial pressure, andfinally, the right atrial pressure, since these2 chambers have nearly identical pressuresin patients with large atrial defects.*Mild gradients across the pulmonic valve*This relationship does not contradict the findings

of Goodale et al.' in similar cases, where there wasa direct relationship between right atrial pressureand right ventricular stroke work.

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GUNTHEROTH, NADAS, AND GROSS

0-PATIENTS NOT IN CLINICALCONGESTIVE FAILURE

X-PATIENTS IN OVERTCONGESTIVE FAILURE

I4l

2

:rC

E

z

I-

10

2 3 4 6

SYSTEMIC INDEX IL/min/M')

FIG. 8. Graph of the relationship of right atrialpressure to left ventricular output in patients withcomplete transposition of the pulmonary veins.

ranging from 4 to 17 mm. were observed in4 patients. All of these had palpable thrillson physical examination.Although half of our catheterized patients

were in frank congestive failure, the calcu-lated pulmonary vascular resistance was notmarkedly increased in any, with the average

ratio of pulmonary to systemic resistance of1 to 12, the highest being 1 to 7. This is incontradistinction to Burchell 's theory that themain factor causing heart failure is the effortof the right heart to maintain a high flow ofblood against increasing pulmonary resist-ance.9 Similarly, all 13 autopsied cases

showed evidence of congestive failure, butonly 4 showed severe pulmonary vascular ob-struction, and 5 showed only slight changes.

Surgery

Surgical correction of complete transposi-tion of the pulmonary veins was attemptedin 3 instances between January 1954 and Jan-uary 1957 at the Children's Medical Center.The first patient was a 4-year-old girl withall pulmonary veins draining into the leftsuperior vena cava. An anastomosis was

created between the common pulmonary vein

and the posterior wall of the left atrium, in

a horizontal fashion, paralleling the atrioven-tricular ring. The ascending portion of theleft superior vena cava was then ligated anddivided. The patient developed pulmonaryedema, apparently caused by the inadequatesize of the left atrium and ventricle, anddeath followed within 2 hours. Similar ex-periences have subsequently been reported byothers.15' 26 The second patient, an 18-year-old girl with the same anatomic abnormalitywas operated upon in the same fashion, ex-cept that the left cava was not divided, butconstricting stitches were placed to reduce thelumen to approximately one fifth of its pre-vious diameter (fig. 9). A 2-stage operationwas planned with complete division of theascending cava to be attempted later. How-ever, the patient has improved so markedlythat the second stage has been postponed; shewill be re-evaluated shortly.The third patient, a boy 12/3 years old, with

drainage directly into the right atrium, wasoperated upon in an attempt to anastomose theleft pulmonary vein to the left atrium. Thepatient died of blood loss due to complicationsarising from the small size of the structures.

Difficulties similar to our own in correctingthis anomaly surgically, without the use ofopen heart surgery, have been experienced byothers as well. Mustard and Dolan in 1957reported 1 survival.27 Burroughs and Kirk-lin26 reported 9 attempts at correction with-out survival from the literature and one sur-vival of their own.Open heart surgery by means of the pump

oxygenator was first used by Burroughs andKirklin26 in 1956 in 2 patients with 1 surviv-al. In both these cases a side-to-side anasto-mosis between the divided common pulmonaryvein trunk and the left atrium was carriedout with accompanying closure of the patentforamen ovale. Open heart surgery by meansof hypothermia has been used by Mustard andDolan27 in 9 patients with 4 survivals. In 2of the 4 survivors, the vena cava was not com-pletely occluded distal to the entrance of thepulmonary veins, much as in our second pa-tient. Ehrenhaft et al.28 recently reportedthe successful correction of one patient withhypothermia in which the ascending cava was

126

a

6

21

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TRANSPOSITION OF THE PULMONARY VEINS

FIG. 9. The surgical technic employed in the successful firststage repair of completetransposition of the pulmonary veins into an ascending left superior cava.

divided and the atrial septal defect wasclosed.Our very favorable experience with open

heart surgery by means of the pump oxygena-tor in the correction of various intracardiacanomalies suggests that this method will with-out question be the procedure of choice forcorrection of total transposition of the pul-monary veins in the future. If the commonpulmonary vein trunk enters the superiorvena cava, direct anastomosis to the left atri-um will be possible. If the entrance of theveins is into the coronary sinus or the rightatrium proper, then by means of shifting theseptum, the anomalous structures may becaused to drain into the left atrium.*

SUMMARYThe literature on complete transposition of

the pulmonary veins is reviewed. Twenty

*Since this paper was written, 1 patient with totalpulmonary venous transposition into the superiorvena cava has been successfully operated on with theuse of the pump oxygenator. The whole connectionwas severed after a side-to-side anastomosis betweenthe left atrium and the pulmonary venous connectionto the superior vena cava had been made.

patients studied by us are reviewed in detail.There was no correlation between the relativesize of the interatrial communication and theage of death.Frequent symptoms were easy fatigability,

dyspnea, and recurrent respiratory infections.Examination commonly revealed mild cya-nosis, congestive failure, and a characteristictriple or quadruple rhythm. Soft systolicand apical middiastolic murmurs were com-mon; a medium-pitched presystolic murmurwas present in one third.

Electrocardiograms demonstrated markedright ventricular hypertrophy with completereversal of the R/S progression. Radiograph-ic patterns usually could be correlated withthe level at which the pulmonary veins emp-tied. Cardiac catheterization data revealedan interesting inverse relationship betweenright atrial pressure and systemic index.

Patients with drainage into the portal sys-tem formed a unique group. All were males,succumbed early, were more intensely cya-notic, and had marked hepatomegaly. X-raysrevealed a normal-sized heart with intensepulmonary engorgement.

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GUNTHEROTH, NADAS, AND GROSS

Reported experiences with surgical corree-tion are reviewed, and 3 of our operated eases

are presented. Using closed technics, we have1 survivor. Open heart surgery, with a pump

oxygenator, is suggested as the optimal ap-

proach for these individuals.

INCOMPLETE TRANSPOSITION OF THE

PUL-MONARY VEINSDefil it ion

In incomplete transpositioni of the pulmo-nary veins, the major abnormality is theanomalous drainage of part of the pulmonaryreturn into the right atrium or its tributaries.W\Te have excluded fromn our series all cases

with other major cardiovascular lesions, ex-cept a patent foramen ovale or a secunduni-type atrial septal defect.

Incidence

The exact incidence of incomplete transpo-sition of the pulmonary veins is difficult toestimate, since the anomaly may not be sus-

pected clinically and, if the heart is dissectedfrom the lungs in the initial stages of necrop-

sy, anatomic diagnosis may be impossible.There have been well over 100 cases reportediii the literature; and, based on careful stud-ies, the incidence is probably 6 to 10 per 1000routine autopsies.4 29O30 Of the first 37 pa-

tients with secuiiduimi-type atrial septal de-fects operated upon by Gross and Watkins,ii9 had incomplete transposition of the pulmo-nary veins.

EmiibryologyBrow i,32 who first described the develop-

mernt of the pulmonary circulation from partof the presplanchnic plexus, also noted thecentral position of the opening of the com-

mon pulmonary vein in the dorsal wall of thesinus venosus, and described the shift of thepulmonary veins to the left with formationof the atrial septum. Davies and MacCon-aill33 proposed that a portion of the right wallof the commoii pulmonary vein actually ini-tiated the formation of the atrial septum, byinvaginating the dorsal wall of the sinusveimosus. Anomalies of the pulmonary venous

return could logically be attributed either to

a failure of some of the pulmonary veins tomigrate to the left of the developing atrialseptumn, or to defects of septation, perhapsoriginating in abnormal invagination fromthe common pulmonary vein; it is interestingto note in this respect the frequent coexist-ence of atrial septal defects with anomalies ofthe right pulmonary veins.

Anomalies of the left pulmonary veins arerarely associated with atrial septal defects,and are presumably due to failure of thoseveins to connect with the common pulmnona-yvein, and subseqtuent persistence of their earl-ier connections with the branches of the car-dinal veins.

Aniatonmic Coniside rationis

Anomalies of the right pulmonary veintsare at least twice as frequent as anomalies ofthe left. The anomalous right pulmonaryveins drain most commonly into the superiorvena cava or right atrium, and are frequentlyassociated with an atrial septal defect.Anomalies of the left pulmonary veins aremore apt to occur as an isolated abnormali-ty, and usually drain into the left superiorvena cava, left iinnomuinate vein, or coronarysinus. Only 2 cases have been reported ofanomalous drainage of part of both lungs.2The associated changes in the cardiovascu-

lar system at iiecropsy vary with the numberof anomalous pulmonary veins and with thepresence and size of an atrial septal defect.Although, as Brody originally pointed out,"iiicomnplete drainage is not incompatiblewith long life' 12 the complacency of most sub-sequent reviewers toward this anomaly is notjustified by the case reports in the literature.Brody further qualified his prognostication

with the statement that, of 25 patients inwhom more than 75 per cent of the pulmonaryflow returned normally to the left side, allbut 2 lived to be adults. Brody reviewed 42patients without other major cardiac abnor-malities, excepting atrial septal defects, andthe actual age at death varied greatly; how-ever, at least 14 died before the age of 40(table 4). It should be borne in mind that40 years is the average life span of patients

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TRANSPOSITION OF THE PULMONARY VEINS

with atrial septal defects, coarctation of theaorta, and patent ductus arteriosus.7' 34, 3

Such prognostications, based on age at deathof autopsied patients, have no clear validity,particularly when it is uncertain in a largenumber of Brody's cases whether there were

associated septal defects, and whether thecause of death could reasonably be ascribed tothe cardiovascular anomaly under discussion.Certainly, estimates of the volume of theshunt based on the number of anomalouslydraining veins, or even cross-sectional areas

of the veins,30 are inaccurate, since they failto account for differential pressure gradients.

In brief, there is no logical basis for theassumption that incomplete transposition ofthe pulmonary veins is a benign condition,and the significance of the anomaly must beassessed separately in each individual.

Physiology

Incomplete transposition of the pulmonaryveins usually produces a small to moderatesized left-to-right shunt when not accompa-

nied by an atrial septal defect or other majorcardiac abnormality. Right-to-left shuntingon the other hand, causing arterial unsatura-tion, is impossible when the septa are intact,thus, placing this anomaly in a unique posi-tion in the group of left-to-right shunts.Because of the frequent association of

anomalies of pulmonary return with atrialseptal defects, detailed reports of cardiaccatheterization in the isolated anomaly are

infrequent, and often proof is lacking thatthe atrial septum is intact. Jonsson8 reported3 proved cases with intact atrial septum, andthe ratios of pulmonary to systemic bloodflow were 1.9, 1.8, and 1.6. Snellen andAlber 's case23 demonstrated a ratio of 1.4.Friedlich et al.36 reported a patient who hada pulmonary blood flow of 8.3 L. per minuteper M.2 which is more than twice the normalsystemic output, although no calculation ofactual systemic flow was presented. Knut-sen 's37 2 patients had pulmonary flows 1.8and 2.2 times as large as systemic. An atrialseptal defect could not be ruled out in any

of the last 4 patients. However, these figures

TABLE 4.-Age at Death of 42 Cases of IncompleteTransposition of the Pulmonary Veins'

Years Number of deaths

Less than 1 61-20 2

21-40 641-50 551+ 9

"Adults" 11

are predominantly in the range of "large"shunts,34 and, in the presence of marked car-diomegaly, congestive failure, or markedlimitation, these patients would be candidatesfor operative repair. Interestingly, whenpressures in the right heart were reported,they were normal in 7 of 8 cases.8 23 3638As was emphasized in the anatomic discus-

sion, the pulmonary blood flow cannot be ac-curately estimated by the number of anoma-lously draining veins alone. Since rightatrial pressure normally is 4 to 5 mm. Hgless than the left, the pulmonary artery fur-nishes a pressure head effectively 5 mm.greater for flow through an anomalous veinthan through a normally draining vein ofcomparable cross-sectional area. If the pa-tient has 4 normally draining veins, the left-to-right shunt through one anomalous veinof comparable size would be 29 per cent ofthe total pulmonary blood flow, and the totalpulmonary blood flow would be 1.4 timesgreater than systemic.* Similarly, if 2 and3 veins drained anomalously with normalpressures throughout both systems, the totalpulmonary blood flow would be respectively,

*With 4 normal and one transposed pulmonaryvein, assuming equal cross sectional areas for all 5veins, and normal mean pressures in pulmonaryartery, left atrium, and right atrium (viz., 15, 7, and2 mm. Hg, respectively), then:

Qp = Q8 + QapvQapv = Qs 15-2

X4 15-7Qp = 1.4 X QsQapv = .29 Qp

Where Qp = total pulmonary flowQs = systemic flowQapv = flow through anomalous pulmonaryvein(s).

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GUNTHEROTH, NADAS, AND GROSS

2.1 and 3.4. With transposition of 3 pulmo-nary veins, even if the right and left atrialpressures were identical, the total pulmonaryflow would be 2.5 times systemic. These cal-culated figures are of the same order of mag-nitude as those available from the literature.It would, therefore, seem unwarranted a pri-ori to predict a normal life span for patientswith this condition.The importance of 1 or 2 transposed pulmo-

nary veins may be greatly magnified in pa-tients with pulmonary disease, particularlywhere resection or collapse therapy is con-templated. Removal or collapse of a normallydraining lobe would reduce the useful pulmo-nary return proportionally, and in situationsin which 1 entire lung is drained abnormally,resection of the other lung would create com-plete transposition of the pulmonary veins,and survival would depend upon a patentforamen ovale or septal defect. Consequent-ly, any candidate for such procedures shouldbe carefully evaluated, if there is even mini-mal cardiomegaly, engorged pulmonary vas-culature, or shadows suspicious of anomalouspulmonary veins.

Also, it should be borne in mind, that alobe or lung with transposed veins is notnecessarily functionless even though ineffi-cient. It may exchange as much carbon diox-ide and oxygen as the normally draining lungif the parenchyma is normal, since the con-centrations of these gases are the same in bothpulmonary arteries and in both sets of pul-monary veins. The anomalously drained lungmay contribute 50 per cent or more to thetotal body gas exchange, which may be criti-cal in some pulmonary diseases. In suchpatients, resection should be preceded bydifferential bronchospirometry.*

*Arvidsson38 reported the results of bronchospirom-etry in a patient with drainage of all of the rightlung into the inferior vena eava, and with apparentlynormal pulmonary function. The right lung, ab-sorbed 1138 ml. oxygen per minute, the left 212 ml.,although the vital capacity of the 2 lungs was 600and 720 ml. respectively. In this case, the left-to-right shunt would be only 40 per cent of the totalpulmonary blood flow.

Presentation of DataEleven patients with incomplete transposi-

tion of the pulmonary veins have been ob-served by us in the past 6 years. Ten pa-tients were studied by cardiac catheterization,and 9 of these underwent surgical repair.Four patients were autopsied; 1 of these hadnot been diagnosed by catheterization. Ninepatients were found either at surgery or au-topsy to have an associated atrial septaldefect of the secundum type, and a tenthpatient with a calculated pulmonary bloodflow 4 times systemic is presumed to have anatrial defect.Nine patients had anomalous drainage of

1 or more right pulmonary veins into theright atrium. Two of these patients had ad-ditional veins from the right upper and mid-dle lobes draining into the superior vena cava.One patient had only 1 vein from the rightupper lobe draining anomalously into thesuperior cava. In our series, there was noinstance of 2 of the 3 right lobes draininganomalously, but either all the right lobes oronly 1 drained anomalously. Four of 10 pa-tients had single vein transposition, and thesewere all from the right upper lobe.The 1 patient with transposition of the left

pulmonary veins had only a small, patentforamen ovale; the 2 anomalous veins drainedinto the innominate vein and coronary sinusrespectively. This patient died at 2 monthsof pneumonia, and had moderate dilatationand hypertrophy of the right heart. Cathe-terization was not performed.The patients' ages ranged from 2 to 40

years, with an average of 15 years, which isin marked contrast to the ages of patientswith complete transposition of the pulmonaryveins. The sex distribution reflected the in-cidence in patients with atrial septal defects:3 males and 7 females. (The patient withthe isolated anomaly was a male.)

HistoryThere was no family history of heart disease

from any patient, and only 1 patient's gesta-tional history was abnormal, with maternalrubella in the first trimester.

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TRANSPOS1TI(T)N OF THE PULMONARY VEINS

FIG. 10. Representative electroca.trdiogrami of a patielnt with transposition of the rightpulmonary veins, anld anl aItrial septal defect,block and right ventricular hypertrophy.

Dyspnea, fatigue, and freqnjuent respiratoryinfections were the coninioiles.t comlplainlts,occurring in 7 cases. (x-atio~is was not notedby any pareimt. A history of edelma was givenin 2 instances. Two of the older patiellts havedocumente(l histories of pJaroxysmal atrialtachycardia, a frequent finmdin( in older pa-

tients with atrial septal defects. No patientwas completely asymuptonmatic.Physical FiindigsOur patients with inmcomplete tranisipsosition

of l he pulmonaiy veins l)resellted a less strik-ing physical profile than the individuals withthe complete anomaly. Six of the patientswere well developed and 5 were below the

twenty-fifth percentile for height, althoutgh

8 of them were thin. None of them was cy(a-notic or had (lubbed nails. Two patients, 8

alnd1 9 years ol( respectively, were in congres-

tive failure, with hepatomegaly and ellgo(rg(eins. Precordial bulge was noted iii 5 pa-

tients; the point of maximal impulse was at

the lower left sternal border in all. Twopatients had l)alpable thrill in the pulmonicarea: in the first, a systolic thrill was associ-ated with a gradient of 32 mmin. Ilg, across

the pulmonic valve; in the second,( a 20-year-old patient with pulmomiary hypertension, an

early diastolic thrill was demonstrated.On auscultation, the first sound was in-

illustrating inecomplete right bundle-branch

(rease(l in intenisity iii 8 1)atients, all(l iiormlaliii 3. The pulnionic solllld was accentuated in6(, normal ini 5, and alu(lil)ly split in all 1i.A third sound was detected in 4 individualsaan(l a fourth, or atfial sound was preselLt inonly 2. Systolic inurnuirss at the upper leftsternal border w-ere present ini all 10 patientswith atrial septal defects, but not in the pa-tienit with the isolated venious anomaly.. Thesystolic. murmur was soft and blowing incharacter except ini 4 instances. These 4l)atielits had a rolgh, systolic murmur thattransmitted. Durin-g cardiac catheterization,a moderate pre5ssure gradient across the pul-imouin valve wasrt reco(lded. Mid-diastolitmurmurs at the apex or lower left sternial1order, characteristic of large left-to-rightshunts were found ini S patients.34 Threeindividuals had early, high-pitehed diastolicmurmurs at the plmliioiiie area; these l)atiecitswere older (20, 22, and 40 years respective-ly), and 1 had severe pulmonary hylperteni-sion. Four patients had presystolic murmurssimilar to those presellt in complete tralisl)o-sition of the puliimoniai y veins. This murmur,diamoiid-shalped, of medium to high frequen-cy amd synchronrouls with atrial systole, wasaccorni)aliied by a fourth sound in 2 )atients.

Electroca rdiogramThe electrocardiogram of patients with

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GUNTHEROTH, NADAS, AND GROSS

FIG. 11 Top. Representative radiogram in a pa-tient with transposition of the right pulmonary veinsinto the right atrium and an atrial septal defect.

FIG. 12 Bottom. Radiogram of a patient with trans-position of the left pulmonary veins and an intactseptunm.

incomplete transposition of the pulmonaryveins reflects the increased volume of the rightventricle although these changes are lessmarked than in the patients with completetransposition of the pulmonary veins. Rightaxis deviation was present in 9 patients, nor-

mal electric axis in 2. All 11 patients hadright ventricular hypertrophy, but only 5patients, including the 1 with the isolatedanomaly, had marked right ventricular hyper-trophy, as suggested by complete reversal ofthe adult R/S progression, or large rightventricular potentials, or both. Incompleteright bundle-branch block was present in every

instance; right ventricular intrinsicoid de-flection was consistently prolonged, with anaverage of .06 second. Figure 10 shows arepresentative electrocardiogram.The pattern of P pulmonale, so frequent in

complete transposition of the pulmonaryveins, was present in only 3 patients withthe incomplete anomaly. Similarly, T-wavechanges were found in only 4 patients, 2 ofwhom were on digitalis.X-RaysThe radiographic profile of our patients

with incomplete transposition of the pulmo-nary veins was completely nonspecific, al-though quite similar to that in patients withatrial septal defects. The specific patternreported by Steinberg et al.39 observed inpatients with 1 or 2 right pulmonary veinsdraining into the inferior vena cava was notobserved in our cases; in fact, there was noradiologic suggestion of the existence ofanomalous pulmonary veins in any of ourpatients.

Cardiomegaly was present in all of ourpatients: it was slight in 4, moderate in 4,and marked in 3 patients (figs. 11 and 12).In every instance, the ventricular configura-tion was characteristically right-sided. Atrialenlargement was present in 9 patients, butnot in the patient with intact atrial septum.The main pulmonary artery was abnormallyprominent in all patients, with slight to mod-erate enlargement in 8 and marked enlarge-ment in 3. Pulmonary vascular engorgementwas present to a moderate degree in 8 of the10 patients with atrial septal defects; 2 pa-tients had marked engorgement. The patientwith an intact septum had mild engorgement."Hilar dance" was observed in 9 patients; itwas not detected in the 2-month-old patientwith an intact septum, nor in the youngestpatient with an associated atrial septal defect.The aorta was judged to be smaller than av-erage in 5 patients.Angiocardiograms were not performed in

any of our patients with incomplete trans-position of the pulmonary veins.

It is interesting that the patient with anintact septum had moderate cardiomegaly,

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TRANSPOSITION OF THE PULMONARY VEINS

TABLE 5.-Cardiac Catheterization Data of Patients with Incomplete Transposition of thePulmonary Veins, Associated with Atrial Septal Defect

Patient numberAgeNumber of transposed veinsRise in 02 at right atrium (vol. %)(% saturation)

Systemic artery (% saturation)Pulmonic artery (% saturation)Systemic index (L./min./M.2)Pulmonic index (L./min./M.2)Resistances ratio (Pul/Systemic)Wedge pressure (mm. Hg)Right atrial pressure (mm./Hg)Vein entered with defectPosition of ASD

15½213.01996852.66.71/30

6+mid-

281214.83198932.9171/6513100low

32014.42495892.26.51/510*100low

4t2813.31895932.6111/3252

high

5233.52397934.5191/58

6933.42097933.8151/2465.0low

7

9½33.01997925.7131/12

2±high

81633.01597924.2131/11

7+low

9t2232.71599882.56.21/1273±high

post post post post - post post post post post* Actual left atrial pressure.t Patient 4 was catheterized by Dr. D. S. Lukas at the New York Hospital, Patient 9 was catheter-

ized at the Brooke Army Hospital, San Antonio.

and marked right ventricular hypertrophyon electrocardiogram with only 2 pulmonaryveins draining anomalously. His death at 2months was secondary to pneumonia, butthese changes nevertheless suggest that theisolated transposition of even 2 pulmonaryveins may be a moderately serious burden tothe heart.Cardiac CatheterizationTen patients with incomplete transposition

of the pulmonary veins were studied by car-

diac catheterization because of symptoms andsigns suggesting a large atrial septal defect.The 1 patient with an intact septum was notcatheterized. Eight of the 10 patients were

catheterized in our laboratory; 2 adults were

catheterized elsewhere (table 5), although theremainder of their clinical examination andoperative procedures were performed by us.

Arterial oxygen saturation in these patientsshowed no overlapping with those of the totalanomaly; 95 per cent was the lowest satura-tion obtained and the average was 97 per cent.The rise in oxygen saturation at the right

atrial level varied from 15 to 31 per cent,with an average of 20 per cent. This alsoreflects the left-to-right shunt through theatrial septal defect, of course.

Cardiac output varied from 2.2 to 5.7 L.

per minute per M.2, with an average of 3.4,

within normal limits for systemic index. Pul-monary flow ranged from 6.2 to 19 L. per

minute per M.2, with an average of 12. Therewas an average left-to-right shunt of 8.5 1s.and no definite right-to-left shunt in any

patient. These calculated flows are approxi-mations, at best, because a true mixed venous

sample is impossible to obtain.Right atrial pressures in the incomplete

anomaly varied less than in complete trans-position of the pulmonary veins, ranging from2 to 10 mm. Hg, with an average of 5. Theinteresting inverse relationship between leftventricular output and the right atrial pres-

sure that was present in the complete anom-

aly, was also present in patients with incom-plete transposition of the pulmonary veins(fig. 13). The pressure relationship betweenthe right atrium and left atrium (or wedgepressure) was determined in 7 patients, andsimilar to the findings in large atrial septaldefects,25 the gradient between left and rightatria averaged only 2 mm. Hg.

Four patients had gradients across thepulmonic valve of 10, 18, 28, and 32 mm. Hg.Although none of these patients was autop-sied, it seems unlikely that anatomicallydetectable stenosis was present, since they hadflows through the valve of 8, 9, 15, 13, and19 I.. per minute, respectively. It is probable

104033.51998902.98.91/97*60high

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GUNTHEROTH, NADAS, AND GROSS

10

8

E

ir

R 4s

2

X -PATIENTS INCONGESTIVE FA

0 x 0-PATIENTS WIT-CLINICALLY APCONGESTIVE FA

2 3 4

SYSTEM INDEX (L/min/M2)

FIG. 13. Graph of the relationship of r

pressure to left ventricular output in pal

incomplete transposition of the pulmonaryatrial septal defect.

that, at normal flows, the gradientinsignificant.Pulmonary vascular resistance wC

mally increased in only 1 patient, a

old girl, whose calculated resistancedynes-second-cm.-5, and a ratio of pi

to systemic resistance of 1 to 5. Thidied shortly after surgical repair,found to have moderately sever(

hypertrophy and intimal hyperplaspulmonary arterioles. The otherincluding a 40-year-old woman, h,tially normal resistances. The ave

monary vascular resistance in tigroup of catheterized patients is conless than normal, with a ratio of 1 tomonary to systemic, consistent withings of patients with atrial septawithout pulmonary vein anomalies.3Although the possibility of ir

transposition of pulmonary veins wc

ered prior to cardiac. catheterizationot specifically diagnosed in any

the time of catheterization, however,alous pulmonary vein was entered,superior vena cava in 2 cases, andatrium in 4. In the remaining 4 (

pulmonary vein anomaly was disc(the time of operation. Even in ti

VERT in which a pulmonary vein was apparentlyA1OUTE catheterized from the right atrium, the diag-'PARENT ofsAILUE nosis of transposition of a pulmonary vein

should be made with reservations, since it isquite possible to slip across into the left atri-umr through a high, posterior septal defect,into a normally draining vein. Avoiding thiserror requires careful 3-dimenisional cheekson position and frequent sampling. Figure14 illustrates the position of the cardiac cath-eter in anomalously draining veins, subse-quently confirmed at operation.

Although, in some cases, dye-dilution curves

5 6 may help in the diagnosis of co-existence ofincomplete transposition of the pullnonary

iglit atrial v-eins and an atrial septal defect, this technictients with is as limited as that of passing the catheterveins and into the anomalous pulmonary veins. Due

to the proximity of the normally connectingright pulmonary veins to the atrial septal

would be defect, perferential shunting of venous re-turn from the right lung may simulate the

as abnor- curves of anomalous venous connection from20-year- the right lung.40 None of our patients hadwas 328 dye-dilution studies.

ulmonary In view of our present surgical approachis patient to atrial septal defects, the presence of anom-and was alous pulmonary veins is of no major conse-

e medial quence either in selecting candidates for sur-,ia of the gery, or in selecting the external approach.patients, In cases of the isolated anomaly, with an in-ad essen- tact atrial septum, more exact anatomic infor-rage pul- mation would be crucial, in which case,ie entire selective angiocardiography would be of greatsiderably assistance.o 25, pul-the find- Surgery

l defects Seven patients with incomplete transposi-4 tion of the pulmonary veins have been oper-ncomplete ated upon at the Children's Medical Center,3'as consid- by a method similar to that initially describeden, it was by Neptune, Bailey, and Goldberg,4' in whichcase. At pulmonary veins connecting to the right atri-an anom- um, in association with a posterior defect, arefrom the rechanneled by atrioseptopexy. This technicthe right takes advantage of the fact that most, if notcases, the all, cases of incomplete transposition of theovered at pulmonary veins to the right atrium are as-iose cases sociated with posterior defects, which are

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TRANSPOSITION OF THE PULMONARY VEINS

FIG. 14. Radiogram, illustrating the cardiac catheter in pulmonary veins entered fromthe right 3uperior veiia cava and right atrium.

ideally suited for closure by invagination ofthie right atrial wall, thereby enlarging theatrium to include the entry of the anoma-

lously draininig veins, but excluding the sys-

temnie returni fromn the superior and inferiorvenae cavae and coronary sinus.

Anl eiglht latieiit, not included in the(liulical part of this diseussion, was operatedupon recently by means of open heart surgery

through a pumilp oxygentator. This subjecthad a posterior defect ini the atrial septum,1L.5 cm. wi(le amid 2 em. long. Two right pul-

nomIoary veins came into the right atrium.Repair was accomuplished in such a way as tobring the anterior edge of the septal defectover agaiiist the back wall of the atrium, tothe right of time anomalous veins. In this waythe defect was (losed and all the pulmonaryveins were directed into the left atrium.Various surgfical technics have been pro-

posed to corrrect the drainage of veins intothe right superior veiia cava. Since the ex-

ternal approach for atrioseptopexy is throughthe righlt chest, actual transplantation of theveins into thme left atrium is difficult, if notimpossible, without open heart surgery. Re-section of a lobe or entire lung should beregarded as a last resort, amid should be pre-

ceded by (areful studies of cardiac and pul-muonary fnuicetioins, ii (luding differentialbronichosp)iromnletry. Two of our lpatients withatrial septal defects and partial transpositionof the pulmonary vseins had this anatoinic

situation. Only the atrial defect was repairedin these children. Ehrenhaft et al.28 reported4 patients operated upoIl with hypothermia,with closure of atrial defects. They trans-planted the superior venia cava, and in 2 ofthese patients, they utilized an arterial graft.

Ltigation of the anomalous pulmonary veinsseems less than completely satisfactory. Li-gation of all the veins froni 1 lung is frequent-ly fatal.43 Tying off a single vein, althoughwell tolerated in 1 of our patients, may causecongestion of the involved lobe. Also, theanastomoses connect with the bronchial veins.or with the parietal veins, both of which ul-timately drain into the right atrium, sincethere are no importa ut translobar anlastomoseswith normally draininig pulmuonary veins.

Moderate. or even severe pulmol-ary hyper-tension in a patient w^ith an intact atrial sep-tum, and incomplete transposition, would notbe a conitraindicatioin to surgery, since repairwould diminish the right ventricular workand increase the left-sided return. This is iincontradistinction to patients with atrial sep-tal defect and severe pulmonary vascularobstruction, in whoin a right-to-left shnlntthrough the septal defect may allow moreadequate systemic output as this disease pro-gresses.Of the 10 patietlts with atrial septal defect

and transposed pulmonary veins to the pres-ent time, 8 had successful closures of the sep-tal defect and correction of all the anomalous

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GUNTIJEROTH, NADAS, AND GROSS

drainage. In the 2 with superior vena cavadrainage, only the atrial septal defect wasrepaired. There were 2 deaths: 1 secondaryto infarction of the right atrial wall includingthe pacemaker, and 1 in whom a plasticbutton was used in the early stages of devel-oping operative approaches for repair ofatrial septal defects. The results obtained inthe surviving patients are considered excel-lent.

SUMMARYThe seriousness of incomplete transposi-

tion of the pulmonary veins has probablybeen underestimated in the past.Data on 11 patients is presented, including

10 with associated atrial septal defects. Com-mon symptoms were dyspnea, fatigability,and frequent respiratory infections. Exam-ination revealed no cyanosis, widely splitsecond sound, soft systolic murmur and mid-diastolic murmur at the apex. One thirddemonstrated a presystolic murmur of medi-um pitch. The electrocardiographic and ra-diographic features were characteristic ofatrial septal defects. There were no specificvascular shadows in any of our patients.Catheterization data were also characteristicof atrial septal defects. There was an inverserelationship between the right atrial pressureand systemic index. Anomalous pulmonaryveins were entered during the right heartcatheterization in 6 of the 10 patients cath-eterized.

Seven patients have had atrioseptopexy toclose the septal defect and to direct the bloodfrom the anomalously draining veins into thenewly enlarged left atrium. An eighth pa-tient had repair and shift of the atrial sep-tum by means of open heart surgery througha pump oxygenator. This approach willprobably prove optimal for future operations.

ACKNOWLEDGMENTThe cardiac catheterizations reported in this

paper were performed by Drs. Walter T. Goodaleand Abraham M. Rudolph, in the CardiovascularLaboratory of the Children's Medical Center, Bos-ton, with the exception of 2 patients with incom-plete transposition of the pulmonary veins cathe-terized by Dr. D. S. Lukas, at the New York

Hospital, and 1 patient at the Brooke Army Hos-pital, respectively. Permission to include thesedata is gratefully acknowledged. We also wishto thank Dr. M. W. Wittenborg, who reviewedthe radiographic findings, and Dr. J. B. Craig,for reviewing the anatomic findings.

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TRANSPOSITION OF THE PULMONARY VEINS

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