Structure and function of the tricuspid and

bicuspid regurgitant aortic valve: an

echocardiographic study

Mattias Rönnerfalk and Eva Tamas

Linköping University Post Print

N.B.: When citing this work, cite the original article.

Original Publication:

Mattias Rönnerfalk and Eva Tamas, Structure and function of the tricuspid and bicuspid

regurgitant aortic valve: an echocardiographic study, 2015, Interactive Cardiovascular and

Thoracic Surgery, (21), 1, 71-76.

http://dx.doi.org/10.1093/icvts/ivv072

Copyright: Oxford University Press (OUP): Policy N / European Association for Cardio-

thoracic Surgery

http://www.oxfordjournals.org/

Postprint available at: Linköping University Electronic Press

http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-120278

Funding: The work was supported by the Swedish Heart Lung Foundation [HLF 20120570]

and ALF Grants from the County Council of Östergötland, Sweden [LIO-204141].

.

Structure and Function of the Tricuspid and Bicuspid Regurgitant Aortic Valve - an

echocardiographic study

Mattias Rönnerfalk †*‡, Éva Tamás*‡

†Department of Clinical Physiology and *Department of Cardiothoracic Surgery, Heart and

Medicine Centre, Linköping, ‡ Division of Cardiovascular Medicine, Department of Medical and

Health Sciences, University of Linköping, Sweden

Abstract word count: 326 (excl. Keywords)

Text word count: 2886 (excl. Fig.,table,ref.)

Corresponding author:

Mattias Rönnerfalk

Dept. of Cardiothoracic Surgery

Heart and Medicine Centre

581 85 Linköping

Sweden

Telephone: +46 10 103 48 15

Fax: +46 +46 13 10 02 46

e-mail: mattias.ronnerfalk@regionostergotland.se

2

Abstract

Objectives:

The emerging new treatment options for aortic valve disease call for more sophisticated diagnostics.

We aimed to describe the echocardiographic pathophysiology and characteristics of the purely

regurgitant aortic valve in detail.

Methods:

Twenty-nine men, with chronic aortic regurgitation without concomitant heart disease referred for

aortic valve intervention, underwent 2D transesophageal echocardiographic (TEE) examination

prior to surgery according to a previously published matrix. Measurements of the aortic valve

apparatus in long and short axis view were made in systole and diastole and analysed off-line. The

valves were grouped as tricuspid (TAV) or bicuspid (BAV) and classified by regurgitation

mechanism.

Results:

Twenty-four examinations were eligible for analysis of which 13 presented TAV and 11 BAV. The

regurgitation mechanism was classified as dilatation of the aorta in 6 cases, as prolapse in 11 cases

and as poor cusp tissue quality or quantity in 7 cases. The ventriculoaortic junction (VAJ) and valve

opening were closely related (TAV r = 0.5, BAV r = 0.73) but no correlation was found between the

VAJ and the maximal sinus diameter (maxSiD) or the sinotubular junction (STJ). However, the STJ

and maxSiD were significantly related (TAV vs. BAV: systole r = 0.9, r = 0.8; diastole r = 0.9, r =

0.7) forming an entity. The conjoined BAV cusps were shorter than the anterior cusps when closed

(p = 0.002); the inter-commissural distance of the cusps in the BAV group were significantly

different (p = 0.001 resp. 0.03) in both systole and diastole.

Conclusions:

3

The VAJ was independent of other aortic dimensions and should thereby be considered as a

separate entity with influence on valve opening. The detailed 2D TEE measurements of this study

add further important information to our knowledge about the function and echocardiographic

anatomy of the pathologic aortic valve and root either as a stand-alone examination or as a

benchmark and complement to 3D echocardiography. This may have an impact on decisions

regarding repairability of the native aortic valve.

Key words:

aortic valve insufficiency, transesophageal echocardiography, tricuspid valve, bicuspid valve,

cardiac surgery

4

Introduction

The prevalence of aortic regurgitation (AR) is 13% in men and 8.5% in women reported by the

Framingham Heart Study [1]. The aortic valve can be incompetent due to inflammatory process,

tissue degeneration as in tricuspid aortic valve (TAV) or affected congenitally as in bicuspid aortic

valve (BAV). The incidence of BAV is 0.9-1.36% [2] and the malformation usually does not affect

hemodynamics in children. The turbulent flow characteristics and the tissue changes may result in

both aortic stenosis (AS) and AR. Symptoms of chronic AR may occur first in the young adult or in

the middle-aged individual [3]. In surgical series of patients with BAV 69% of the patients were

men; 75% suffered from AS (mean age 65 years) and 13% had AR (mean age 46 years) and only

1% of the BAVs functioned normally [4]. In a study of patients with pure AR from the Mayo Clinic

[2], 20% of the valves proved to be bicuspid.

Regurgitant aortic valves can be classified by echocardiography based on the mechanism causing

regurgitation. Both LePolains de Waroux et al. and Lansac et al. have presented valid

classifications. LePolain de Waroux et al. focused mainly on cusp morphology classifying

enlargement of the aortic root with normal cusps as type 1, cusp prolapse or fenestration as type 2,

and poor cusp tissue quality or quantity as type 3. Regurgitation mechanisms type 1 and 2 are

generally considered to be candidates for aortic valve repair [5]. Lansac et al. had aortic root

dilatation with (type I) or without (type II) cusp lesion as the starting point for their classification

and defined subgroups Ia as dilatation of the sinotubular junction (STJ) and Ib as simultaneous

dilatation of the ventriculoartic junction (VAJ) and the STJ. Subgroup IIa includes cusp prolapse,

IIb cusp retraction and IIc tear or perforation of the cusp tissue [6]. Type I lesions are generally

characterized by a central jet on echocardiography while type II lesions cause an eccentric jet.

According to current guidelines [7] aortic valve replacement (AVR) is the choice of treatment for

patients suffering from AS. However, for patients with AR (especially in physically active young

individuals) preservation of the native valve eliminates possible complication due to patient

prosthesis mismatch and warfarin treatment [8, 9], thereby leading to improved morbidity measures

5

and better quality of life for these patients. Regurgitant tricuspid aortic valves are reconstructed and

preserved with good short and medium term results measured by grading residual and/or recurrent

AR postoperatively [10, 11]. A few studies have been published on preserving BAV with promising

initial results [12]. The pre- and intraoperative evaluation and the postoperative follow-up of the

aortic valve were performed by echocardiography, preferably transesophageal echocardiography

(TEE). Even though a complete echocardiographic TEE examination is performed pre-operatively

the decision, whether or not the valve is possible to reconstruct, is made in the operating theatre by

surgical visual examination. Therefore a more standardised approach to the preoperative

examination could aid surgeons’ assessment and planning of the surgical intervention.

The clinical application of 3D TEE has been expanding. During only a decade the development

went from early reports of simple examinations of the aortic valve apparatus [13] to high quality

real-time examinations. Nevertheless, 2D TEE still forms the basis of clinical decisions and

description concerning aortic valve morphology in most of the tertiary centres.

The aim of the present study is to describe the detailed echocardiographic pathophysiology and

characteristics of the purely regurgitant aortic valve by 2D TEE.

6

Materials and Methods

A series of 29 patients referred to our centre for surgical interventions due to severe chronic aortic

regurgitation were included in this study. Patients with concomitant coronary artery disease, other

heart valve disease than chronic aortic regurgitation (aortic stenosis defined as aortic orifice area ≤

1.6 cm²; any history of active endocarditis) and with ascending aortic aneurysm were excluded. All

the patients underwent transesophageal ultrasound scan at rest (Vivid 5 or Vivid 7 ultrasound

system, GE Healthcare, Wauwatosa, WI) one day prior to the planned surgery. Images were

recorded, stored digitally and analysed off-line. Measurements on the aortic root and the cusps were

taken according to a previously published matrix [14], which was proved reliable and highly

reproducible. The analyses of AR mechanisms were performed according to the classification

presented by LePolain de Waroux et al. chosen for its versatility in clinical practice.

In absence of a comprehensive definition, including numerical cut-off for raphe, for

echocardiographic classification of BAV a merger of different, although not comprehensive

classifications eligible for echocardiographic use was constructed [15-17] to enable classification of

valves with challenging echocardiographic image. The aortic valve was classified as TAV when

having three visible cusps, three identifiable commissures as absolute criteria and a Y-shaped valve

opening in systole with a raphe/fusion less than 10 mm as relative criteria. To be classified as BAV

two visible cusps and two identifiable commissures were required as absolute criteria and a fish

mouth shaped valve opening and a raphe/fusion longer than 10 mm as relative criteria.

In summary, 2D ECG-synchronized cine loops of the aortic root in the long and short axis views

were recorded. Parameters (Fig.1.) were measured in end-diastole and end-systole using the inner

edge technique. Each parameter was measured three times and the mean was entered into the

statistical analysis. Systolic and diastolic parameters, as well as characteristics for tricuspid and

bicuspid valves were analysed by Mann-Whitney and Sign test, Wilcoxon’s matched paired test or

Friedman ANOVA, as appropriate, due to sample size and distribution pattern. Tree clustering

(Ward’s method based on variance) was used to detect relationships among parameters. For further

7

specification of relationships of significance within a cluster, Spearman’s rank order correlation (r)

was applied. Significance was set as p ≤ 0.05 throughout the statistical analysis. All statistical

analyses were performed by STATISTICA 10.0 Statsoft, Tulsa, Okla., USA. The Regional Ethical

Review Board in Linköping, Sweden approved the study.

8

Results

All of the included patients happened to be men. The echocardiographic images were technically

satisfactory and eligible for detailed analyses in 24 cases. Patients were grouped based on having

tricuspid or bicuspid valve according to the above definition. The demographic characteristics of the

two groups were comparable except that patients with BAV were significantly younger (Table 1).

The echocardiographic measurements and a comparison between TAV and BAV are presented in

Table 2. The opening of the valves was comparable for both BAV and TAV. Raphe was observed

between the left and the right coronary cusp in all but one case and the two cusps were unequal [4],

the conjoined cusp being bigger in all BAV cases. However, the inter-commissural distance of the

non-coronary cusp of TAVs and the anterior cusp of the BAVs were comparable.

Long axis view

A close relationship between the VAJ and valve-opening both in tricuspid (r = 0.5) and bicuspid (r

= 0.73) valves was verified. The VAJ, the STJ and the maximal sinus diameter (maxSiD) were

found to be significantly related only in the BAV group in systole (r = 0.6 each). The STJ and the

maxSiD were significantly related both in the TAV and the BAV groups in systole (r = 0.9, r = 0.8)

and in diastole (r = 0.9, r = 0.7).

The height of cusps (TAV: r = 0.9 resp. 0.9; BAV: r = 0.9 resp. 0.8) and sinuses (TAV: r = 0.9 resp.

0.9; BAV systole: r = 0.7) in LAX were significantly correlated throughout the heart cycle with the

exception of sinus height for BAV in diastole (r = 0.6), Fig.2. There was an indication of variation

in aortic measurements between diastole and systole in BAV (VAJ p = 0.09, maxSiD p = 0.02, STJ

p = 0.15).

Short axis view

The commissural distance of the TAV cusps were not significantly different (p = 0.55 resp. 0.23)

from each other. However, the inter-commissural (IC) distance of the anterior and the posterior

cusps in the BAV group were significantly different (p = 0.001 resp. 0.03) in both systole and

diastole. The commissure-to-raphe distance was not significantly different from the raphe-to-

9

commissure distance (Fig.1.) but both were significantly less than the IC- distance of the anterior

cusp when the valve was closed (p = 0.002 resp. 0.07).

Mechanisms of aortic regurgitation

All the patients had hemodynamically significant aortic regurgitation. The regurgitation

mechanisms in the TAV group were classified as five type 1, four type 2 and four type 3. The

distribution for the BAV group was one type 1, seven type 2 and three type 3.

10

Discussion

The main findings of the present study were that (A) the diameter of the ventriculoaortic junction

proved to be significantly related to the opening of the valve both in TAV and BAV but (B) it was

found to be a separate entity, not related to either the STJ or the maxSiD.

Both TAV and BAV have been studied previously in chronic aortic regurgitation but comparative

data are scarce, mainly focusing on functional aspects. Thus, the novelty of the present study

consists mainly of describing further complementing echocardiographic details and relations. The

anatomy, in particular the echocardiographic anatomy of the aortic root and mechanism of

regurgitation has an impact on planning aortic valve interventions, most specifically valve

preserving surgery which is well-established and performed with good results in some centres [10-

12] both on bicuspid and tricuspid valves but still not widely used in surgical practice. This is partly

due to the complexity of the anatomy of the normal aortic root [18], partly because of the fully

functional but anatomically basically different variations as in tricuspid and bicuspid valves.

Furthermore, the different anatomy has apparent implications for tissue quality [19, 20].

The significant difference in the age of the patients between TAV and BAV in this study can be

explained by the different aetiology of the chronic aortic regurgitation [19], which is concordant

with previous findings [4]. The comparison of the echocardiographic dimensions according to size

showed that the majority of parameters were larger in TAV. This is, however, contradictory to

previous knowledge which states that the aortic root containing a BAV is larger and more prone to

dilatation, even more so in reguritant BAV [21]. Aortic dimensions for both TAV and BAV in this

study were larger than diameters of the healthy aortic roots and most so in the TAV group. VAJ and

maxSiD changed less than one mm between systole and diastole in healthy TAV and the difference

was the same for STJ [14]. In this study of chronic aortic regurgitation there was a non-significant

change in TAV for VAJ, maxSiD and STJ but noticeably larger aortic dimensions. The difference

in diameters throughout the cardiac cycle was significant for maxSiD in BAV and a certain trend in

11

VAJ and STJ, indicating increased compliance in the aortic wall, was detected. Similar findings

were described in a sample of mildly regurgitant bicuspid valves [22] but as our design did not

include studies of elasticity or distensibility it does not allow any conclusions in this aspect. Since

we did not find any general dilatation of the aorta in the BAV group the hemodynamically

significant AR might be a forerunner and even the cause of imminent dilatation. The larger aortic

dimension in AR TAV and the increased aortic wall compliance of the BAV compared with

previously studied healthy valves are notable [14]. These two findings might indicate a selection

bias due to exclusion of patients with ascending aortic aneurysm.

The diameter of the VAJ was found to be significantly related to the opening of the valve both in

TAV and BAV but it was independent from both the STJ and the maxSiD. This is a finding which

followed the pattern of normal aortic root previously studied by our group [14] and it supports

previous findings made in healthy subjects stating that the VAJ is a separate entity not under the

influence of the aorta and should be considered and treated as such. It seems logical to assume it to

be under the influence of structures and physiological events in the left ventricle when it is not

under aortic influence [6, 14, 23], but that is beyond the scope of this study.

The position of the observed raphe between the left and right coronary cusp and the disparity of the

cusps in this study represented the most common pattern for BAV. This is in concordance with the

findings of Sabet et al. [4], who have published the single largest material on BAV so far, the

pattern of raphe location between the left and the right cusps with unequal cusp size could be seen

in 86% respectively 92% of the cases in their surgical material. Despite our modest number of

subjects this correlated well with the findings for the type of regurgitation. In our patients the most

common type of regurgitation in BAV was type 2 leading us to the conclusion that the conjoined

cusps in the posterior cusp in BAV usually have excessive leaflet tissue. The results of visual

observation of unequal cusps in BAV were confirmed by the statistical comparison of inter-

commissural distances.

12

LePolain de Waroux et al. showed that the echocardiographically classified type of regurgitation

mechanism has prognostic value for the result of valve-sparing surgery. Enlargement of the aortic

root with normal cusps (type 1) and excessive tissue, cusp prolapse or fenestration (type 2) are

candidates for valve-sparing surgery while type 3 regurgitation due to poor cusp tissue quality or

quantity is associated with adverse outcome and more often in need of re-operation resulting in

aortic valve replacement [5]. In the same study there were a number of valves classified as

repairable, type 1 or 2 regurgitations, which were operated on with valve-sparing techniques which

needed re-operation. These valves were suspected of being actually type 3 regurgitations

wrongfully classified visually as repairable by the surgeon. In our material too, there were a number

of TAV classified as type 3 regurgitation due to stretched cusps though with normal VAJ. These

valves may in the future be classified as probably unrepairable based on an extensive

echocardiographic examination incorporated in the process of decision complementing the

surgeons’ visual examination.

The regurgitation mechanisms in our study were evenly distributed in TAV, but with an

overrepresentation of prolapsing valves in BAV corresponding well with our findings of excessive

leaflet tissue in BAV. Our echocardiographic description has the potential to provide additional

knowledge prior to intervention thereby increasing the understanding of both the echocardiographic

anatomy of the regurgitant aortic valve and the possible mechanism of the regurgitation.

Although the clinical application of 3D TEE has been expanding during the last decade, making 3D

TEE an integrated part of transcatheter valve implantation procedures, there is a sparse number of

studies comparing 3D TEE to 2D TEE or validating 3D TEE for describing the morphology and

structures of the aortic valve. Studies comparing 2D TEE and 3D TEE focusing on a few specific

measurements are to be found [24]. Some measurements are not even possible to compare between

the two modalities because of their built-in limitations. Concerning the regurgitant aortic valve, 3D

TEE is validated as a superior method of measuring regurgitant volumes and effective regurgitant

13

orifice area [25]. 3D TEE has also brought new knowledge of the structures and physiology of the

aortic valve and of the aortic root as a complex structure. Real-time 3D TEE examination can today

be performed with an acceptable frame rate. However, although 3D visualization provides valuable

information on spatial relationships and may aid in determination of regurgitation mechanisms, due

to its even higher frame rate and spatial resolution, 2D TEE still has a place in the diagnostics of

aortic valve pathology based on its accuracy, which is needed to expose delicate structures such as

the aortic valve leaflets. Hence 2D TEE can form the basis of clinical decision making regarding

morphology of the regurgitant aortic valve for some time yet and constitute a possible benchmark

for future 3D studies.

The fact that all but one of the BAV showed the same raphe position and inter-commissural

relations limits the generalizability of the findings in this study. However, the one presented here is

still the most common pattern and only less frequent dispositions are absent. Thus, the conclusions

still can be considered representative for the majority of the BAV population. All the patients in this

study happened to be men, which consequently does not allow conclusions to be drawn for women

though studying gender aspects of the morphology of the regurgitant aortic valve was not part of the

study design and, therefore, beyond the scope of this study. The gender distribution in purely

regurgitant BAV was described earlier as 17.3 : 1 [4]. Furthermore, the small number of patients in

this study is balanced by non-parametric analyses of the data to enhance generalizability.

In conclusion, the detailed 2D TEE measurements of this study can add further important

information to our knowledge about the function and echocardiographic anatomy of the pathologic

aortic valve and root as a stand-alone examination or as a benchmark and complement to 3D

echocardiography. This could have an impact on planning the type of aortic valve intervention.

Fundings

This work was supported by the Swedish Heart Lung Foundation [HLF 20120570] and ALF Grants

from the County Council of Östergötland, Sweden [LIO-204141].

14

Conflicts of interest

Conflicts of interest: none to be declared

15

Figure 1 Echocardiographic parameters of the aortic root with a bicuspid valve

16

Figure 2 Tree cluster analyses for variables seen in the long axis view

TAV LAX systole

0,00,2

0,40,6

0,81,0

1,21,4

1,6

Linkage Distance

RC Sinus HeightLC Sinus Height

STJMax Sinus Diameter

RC Cusp HeightLC Cusp HeightCusp separation

Ventriculoaortic Junction

TAV LAX diastole

0,00,2

0,40,6

0,81,0

1,21,4

1,6

Linkage Distance

RC Cusp Height

LC Cusp Height

RC Sinus Height

LC Sinus Height

STJ

Max Sinus Diameter

Ventriculoaortic Junction

BAV LAX systole

0,00,2

0,40,6

0,81,0

1,21,4

1,6

Linkage Distance

Posterior Cusp HeightAnterior Cusp Height

Posterior Sinus HeightAnterior Sinus Height

STJMax Sinus Diameter

Cusp SeparationVentriculoaortic Junction

BAV LAX diastole

0,00,2

0,40,6

0,81,0

1,21,4

1,6

Linkage Distance

Posterior Sinus Height

Anterior Sinus Height

Posterior Cusp Height

Anterior Cusp Height

STJ

Max Sinus Diameter

Ventriculoaortic Junction

17

Figure 3 Tree cluster analyses for variables seen in the short axis view

TAV SAX systole

0,0 0,3 0,6 0,9 1,2

Linkage Distance

RC Cusp Diameter

IC Distance NC Sinus

IC Distance RC Sinus

NC Cusp Diameter

LC Cusp Diameter

IC Distance LC Sinus

TAV SAX diastole

0,0 0,3 0,6 0,9 1,2

Linkage Distance

NC Cusp Diameter

IC Distance NC Sinus

RC Cusp Diameter

IC Distance RC Sinus

LC Cusp Diameter

IC Distance LC Sinus

BAV SAX systole

0,00,5

1,01,5

2,02,5

Linkage Distance

Posterior Cusp Diameter 2

Posterior Cusp Diameter 1

NC Cusp Diameter

IC Distance Posterior Cusp

Raphe-to-commissure Distance

IC Distance NC Sinus

Commissure-to-raphe Distance

BAV SAX diastole

0,00,2

0,40,6

0,81,0

1,2

Linkage Distance

Posterior Cusp Diameter 1

Posterior Cusp Diameter 2

IC Distance NC Sinus

Commissure-to-raphe Distance

Raphe-to-Commissure Distance

IC Distance Posterior Cusp

18

Table 1 Patient characteristics

Tricuspid

N = 13

Bicuspid

N = 11

p

Age (yrs) 61 ± 12 42 ± 11 < 0.001

Height (cm) 177 ± 4 181 ± 8 0.22

Weight (kg) 87 ± 11 89 ± 17 0.76

BSA (m2) 2.0 ± 0.1 2.1 ± 0.2 0.26

BMI (kg/m2) 28 ± 3 27 ± 3 0.67

19

Table 2 Tricuspid and bicuspid aortic valve parameters

Tricuspid (mm) Bicuspid (mm)

Systole Diastole ps pd Systole Diastole

Ventriculoaortic

junction

25 ± 4 24 ± 3 0.05 0.08 28 ± 3 27 ± 3 Ventriculoaortic

junction

Maximal Sinus

Diameter

42 ± 6 41 ± 6 0.07 0.02 38 ± 5 36 ± 6 Maximal Sinus

Diameter

STJ 38 ± 8 39 ± 9 0.02 0.02 32 ± 6 31 ± 6 STJ

Opening (Cusp

Separation)

22 ± 7 - 0.95 22 ± 4 - Opening (Cusp

Separation)

Coaptation - 0 - 0 Coaptation

LC Cusp Height 11 ± 3 8 ± 3 0.49 0.11 12 ± 4 6 ± 4 Posterior Cusp

Height

RC Cusp Height 12 ± 3 8 ± 3 0.49 0.17 12 ± 3 6 ± 4 Anterior Cusp

Height

LC Sinus Height 22 ± 8 21 ± 7 0.69 0.46 20 ± 4 20 ± 5 Posterior Sinus

Height

RC Sinus Height 24 ± 9 24 ± 8 0.23 0.39 20 ± 4 20 ± 4 Anterior Sinus

Height

IC Distance LC

Sinus

30 ± 5 27 ± 4 0.07 0.15 27 ± 3 25 ± 3 Commissure-to-

raphe Distance

Posterior Sinus

IC Distance RC

Sinus

31 ± 4 29 ± 4 0.004 0.006 26 ± 4 24 ± 4 Raphe-to-

commissure

Distance

Posterior Sinus

- 52 ± 6 49 ± 7 IC Distance

Posterior Sinus *

IC Distance NC

Sinus

31 ± 4 28 ± 5 0.53 0.69 32 ± 4 28 ± 4 IC Distance

Anterior Sinus

LC Cusp Diameter 10 ± 3 16 ± 3 0.002 0.005 6 ± 2 13 ± 3 Posterior Cusp

Diameter 1

RC Cusp Diameter 10 ± 5 15 ± 6 0.61 0.86 8 ± 2 15 ± 4 Posterior Cusp

Diameter 2

NC Cusp Diameter 12 ± 3 18 ± 2 0.04 0.73 10 ± 4 18 ± 4 Anterior Cusp

Diameter

20

FIGURE LEGENDS

Figure 1

Aortic root and cusp parameters measured in diastole (A & C) and systole (B & D): 1, 2:

ventriculoaortic junction diameter (VAJ); 3, 4: maximal sinus diameter; 5, 6: sinotubular

junction (STJ); 7: valve opening; 9, 10: Posterior cusp height; 11, 12: Anterior cusp height;

13, 14: Posterior sinus height; 15, 16: Anterior sinus height;17, 18: Commissure-to-raphe

distance posterior cusp; 19, 20: Raphe-to-commissure distance posterior cusp; 21, 22: Inter-

commissural distance non-coronary (NC) sinus; 23, 24: Posterior cusp diameter 1; 25, 26:

Posterior cusp diameter 2; 27, 28: NC cusp diameter

Figure 2

BAV: Bicuspid aortic valve; TAV: Tricuspid aortic valve; LAX: long axis view; SAX: Short

axis view; LC: Left coronary; NC: Non-coronary; RC: Right coronary; STJ: Sinotubular

junction; IC: Inter-commissural.

Figure 3

BAV: Bicuspid aortic valve; TAV: Tricuspid aortic valve; LAX: long axis view; SAX: Short

axis view; LC: Left coronary; NC: Non-coronary; RC: Right coronary; STJ: Sinotubular

junction; IC: Inter-commissural.

Table 1

Patients with bicuspid and tricuspid aortic valve had comparable demographical parameters

except age. BSA: body surface area, BMI: body mass index.

21

Table 2

STJ: Sinotubular junction; LC: left coronary; RC: Right coronary; NC: Non-coronary; IC:

Inter-commissural. Measures in mm, mean ± SD. * calculated from commissure-to-raphe

distance posterior cusp and raphe-to-commissure distance posterior cusp.

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