ABSTRACTS

WEDNESDAY, MARCH 16, 1981 PM HVPERTENSION-THEORV, EXERCISE TESTING, VASCULAR REACTIVITY, DIASTOLIC ABNORMALITY 2:00-3:30

EFFECT OF BETA BLOCKADE-THERAPY ON HYPERTENSIWZ CARDIAC HYPERTROPHY M.Mohsen Ibrahim,MD,FACC; M.Aziz Madkour,MB,BCh Raaaa Mossallam.MB.BCh. Universitv of Cairo and Cairo TransportVOrganiiation,Cairo,Egypt.

The effect of B-blockade therapy on LV mass(LVM) has not been studied in hypertensive patients. Studies in animals have shown that certain anti-hypertensive drugs reduce cardiac hypertrophy. Atenolol(A)- a cardioselective beta blocker with no intrinsic sympathomimetic activity- was given(100mg/d) for 8 weeks to 17 male patients with es- sential hypertension (mean age 49~) and without evidence of other cardiac disease. Echocardiographic dimensions (ED)and urinary epinephrine(UE) were determined after 4 weeks placebo and after A therapy. ED were measured in 16 age matched normotensive males. Septal(S) and poster- ior wall(PW) thickness(T),LVM index(LVMI),ratio of LVWT to radius(h/r),UE and mean circumferential wall stress (McS) were all significantly increased(p< 0.01) in hyper- tensive patients. Following A blood presswe decreas- ed flGan 197/119 f 5.7/3.9(mean f SE) to 160/98 f 2.9/2.3 nrmHgCp& O.OOl), ST from 11.1 f 0.5 to 10.4 _I 0.4 mm (p (0.05). LVMI from 126 f 10.1 to 112 f 8.5 qm/m2 (p <0.005), MCS fran 342 t 20.1 to 264 f 17 103dynes/cm2 (p <O.OOl), end diast.diameter(EDD) from 51.9 f 1.3 to 50.8 + 1.4 mm (pcO.05) and U!Z from 149 f 9.6 to 91 f 4.4 mcg/24hs.(p <O.OOl). PWT and h/r did not change.ALVMI was significantly related toAMCS(r = 0.42),poorly relat- ed to Asyst.BP(r = 0.32)and AuE(~ = 0.22)and not relat- ed to Adiast.BP(r = 0.03). CONCLUSI0N:l.A produced a ra- pid decrease in LVM,however,some of the changes might be due to a decrease in EDD since h/r did not change.2.Reg- ression of cardiac hypertrophy appears to be more depend- ant on reduction in wall stress than a direct hypotensive effect of therapy or decrease in adrenergic activity (UE).

EVIDENCE FOR ALTERED VASCULAR REACTIVITY IN YOUNG SUBJECTS WITH LABILE, BORDERLINE HYPERTENSION Jay M. Sullivan, MD, FACC; Darrell R. Patrick, BS; Steve W. Reed, MD; Ahmad Banna, MD; John C. Riddle, MD; Collier Jordan, MD, University of Tennessee, Memphis, TN

Forearm hemodynamics were measured by venous occlusion plethysmography during periods of ad lib diet, 10 mEq so- dium diet and 200 mEq sodium diet in 15 normal subjects (NL) and 15 subjects with labile, borderline hypertension (BBP). The two groups did not differ significantly in re-

9 ard to age, sex or race. Average resting blood pressure BP) in the normal group was 110/74 and 122/85 in the BBP group (pc.005). Resting forearm blood flow (FBF), forearm vascular resistance (FVR), venous compliance (VC) and capillary filtration coefficient (CFC) did not differ sig- nificantly between the two groups. In both groups, dia- stolic blood pressure was highest when first measured dur- ing the ad lib state (81 nmHg) and lower during the 10 mEq (79 mnHg) and 200 mEq (78 mnHg) sodium state (pc.01). Venous capacitance was lowest during the ad lib state, 0.50 vs 0.70 and 0.57 ml/min/mnHg/lOO g x lo4 (pe.05). In the normal group, the 10 and 200 mEq sodium diets had little effect on forearm hemodynamics. Sodium depletion brought out a difference between the NL and BBP subjects. The FVR of the BBP subjects rose significantly during salt depletion, 35.9 vs 60.9 mnHg/ml/min/l00 g (pc.05) while that of the NL subjects did not. Sodium sensitivity was arbitrarily defined as an increase in mean blood pressure of more than 5% when sodium repleted. The individuals who were salt sensitive had a higher FVR during sodium de- pletion than those who were salt resistant, 64.9 vs 44.6 mnHg/ml/min/lOD g (p<.O3). We conclude that young in- dividuals whose resting diastolic BP intermittently rises above 90 nsnHg already have alteration in vascular re- activity.

EFFECl'IVEANDGAFETREXNNTOF BYPEwEwlsE CRISIS WrIw RIFEDIPINE. Dieter mgg, M.D.; Max Pichler, M.D.; I. M~Szinische Universi~tsklinik, Wien, Austria

The pxsent nnnaganent of hypertensive crisis with nitro- psside, diamxideorh@ralazinerequiresclosemnito- ring of blood Fessure (BP) am3 dose of the administered drug duetopossible side effects. We investigated the effectiveness and safety of nifsdipine to patients with hypertensive crisis. Twnty milligrmw nifedipine were given orally to 7 pts. suffering fran a marked rise of bleed Ixessure of>250 nnHg systolic and >I40 mnEg diastolic as ~~11 as typical clinical manifesta- tions (headache, nausea, visual loss, restlessness and ccnfusion). Blood pressuresweremeasured by themethcd ofRivaWxci.Blood~essurearrlheartrate~etaken 20, lo minutes and imnediately before application and lo, 20, 30, 45, 60 and 9o minutes later. Results (mean f 51)) were as follcws:

-20 -10 0 lo 20 30 45 6o %nLin.

syst. 272 256 257 237 179 177 177 176 176 BP 32 26 40 28 28 27 22 25 28

diast. 159 158 157 147 121 105 102 98 104 BP 18 lo 13 9 16 15 14 19 13

HR 69 68 71 64 74 77 74 74 73 17 17 16 19 19 19 18 19 17

Nifdipine caused in all patients a ~a@ decrease of the elevated blood pressure. Its onset was within lo minutes and reached themaximal effect by 30minutes. Thedropof hlood~essure~sconcanitantwithamarked~~-t ofsymptrms.OfimFortance,therewerenosignsofaver- shoot or tachycardia. Therefore, nifdipine appears to be hotha safe and effectivedrug in themanagmventof acute hypertensive crisis.

DIASTOLIC VENTRICULAR ABNORMALITY IN HYPERTENSIVE HEART DISEASE: ATRIAL EMPTYING INDEX Gerald R. Dreslinski, MD; Edward D. Frohlich, HD,FACC; Francis G. Dunn, MD; Franz H. Messerli, MD,FACC; Daniel H. Suarez, MD; Efrain Reisin, MD. Ochsner Medical Institutions, New Orleans, LA.

Left ventricular (LV) diastolic properties in hypertensive heart disease were analyzed, employing the atria1 emptying index (AEI), thereby assessing the rapid phase of LV diastolic filling. 10 normal subjects (Group l), 11 hypertensive patients without evidence of cardiac involvement (Group 2), and 9 hypertensive patients with ECG and/or echocardiographic evidence of LV hypertrophy (Group 3) were studied by concomitant M- mode echocardiography and systemic hemodynamics. Whereas cardiac index (dye dilution), and fiber shortening rate (V

%I by echocardiogram) were similar in

all three groups, ere was a progressive increase in left2atrial index (LAI) (1.30 vs 1.74 and 1.30 vs 1.84 cm/m , Group 1 vs Group 2 and Group 3, respectively; p(O.OOl), and a progressive decrease in AEI (0.82 vs 0.63, ~(0.001, Group 1 vs Group 2, and 0.82 vs 0.60, p<O.O2, Group 1 vs Group 3). No correlation existed between the AEI and the LAI, mean arterial pressure, or total peripheral resistance, in these three groups.

These data suggest that the LV is less compliant early in hypertension, before ECG, anatomic or LV systolic echocardiographic abnormalities are detectable. AEI , therefore, appears to be an early indicator of abnormalities of LV diastolic compliance, thus far the earliest sign of cardiac involvement in hypertensive disease.

February 1991 The American Journal of CARDIOLOGY Volume 47 469