Multi-modal bicuspid aortic valve classification: diagnostic agreement and accuracy

The purpose of this study is to evaluate the diagnostic performance of CT, compared with that of echocardiography and surgery, for differentiating between bicuspid and tricuspid aortic valves. Forty-seven patients with bicuspid valve and 47 patients with tricuspid aortic valve underwent retrospectively ECG-gated dual-source CT and echocardiography. Thirty-four (72%) of the 47 patients with bicuspid aortic valve underwent valve surgery. Two independent blinded observers assessed the CT image quality of the aortic valve during diastole and systole on a 4-point scale, determined which phase allowed the differentiation of valve type, distinguished between tricuspid and bicuspid aortic valves, and assessed for the presence of a raphe. Diagnostic performance of CT was determined using echocardiography and surgery as the reference standard. According to echocardiography and surgery, seven (15%) of the 47 bicuspid aortic valves had no raphe, and 40 (85%) had a raphe. CT image quality was diagnostic (i.e., scores of 1-3) in all 94 patients in both diastole and systole. Among patients with bicuspid aortic valve and no raphe, differentiation between tricuspid and bicuspid aortic valves could be performed in diastole in 100% (7/7) of cases. Among patients with bicuspid aortic valve and raphe, differentiation was possible only in systole in 5% (2/40) of cases and when combining diastole and systole in 95% (38/40) of cases. In three bicuspid aortic valves with raphe, the valve was misclassified by CT as tricuspid aortic valve. Overall sensitivity and specificity of CT for the diagnosis of bicuspid aortic valve were 94% and 100%. CT is highly accurate for differentiation between bicuspid and tricuspid aortic valves. For bicuspid aortic valves without raphe, diastolic reconstructions are sufficient, whereas in those with a raphe, additional reconstructions in systole are required.

Objective To study the value of transthoracic echocardiography(TTE) in diagnosing aortic coarctation on patients with congenital bicuspid aortic valve(BAV). Methods One hundred and thirty-eight patients with BAV who received operation in Zhongshan Hospital Affiliated to Fudan University between July 2011 and July 2016 were analyzed retrospectively.Forty patients underwent TTE as well as CTA before the operation.The results of TTE, computed tomography angiography (CTA) and operation were compared. Results In 138 patients with BAV, three patients were diagnosed as BAV with aortic coarctation.All of them were confirmed by CTA before the surgery.While, only one of the three patients was discovered by TTE before the surgical intervention.Patients with the diagnosis of CTA and TEE were 3/3 and 1/3 respectively.The difference between the two methods had no statistical significance (P=0.200). Three cases of BAV with coarctation were all transverse crack type. Conclusions The difference between two methods(TTE and CTA) on diagnosis of aortic coarctation with BAV do not have statistical significance. CTA is the golden standard of diagnosis of aortic coarctation.Therefore, BAV patients with the symptom of aortic coarctation may receive additional examination like CTA, especially for the transverse crack type. Key words: Echocardiography; Bicuspid aortic valve; Transverse crack type; Aortic coarctation

This International Consensus Classification and Nomenclature for the congenital bicuspid aortic valve condition recognizes 3 types of bicuspid valves: 1. The fused type (right-left cusp fusion, right-non-coronary cusp fusion and left-non-coronary cusp fusion phenotypes); 2. The 2-sinus type (latero-lateral and antero-posterior phenotypes); and 3. The partial-fusion (forme fruste) type. The presence of raphe and the symmetry of the fused type phenotypes are critical aspects to describe. The International Consensus also recognizes 3 types of bicuspid valve-associated aortopathy: 1. The ascending phenotype; 2. The root phenotype; and 3. Extended phenotypes.

Introduction: Patients with bicuspid aortic valves (BAV) and tricuspid aortic valves (TAV) with ascending aortic aneurysms (AAA) are at risk for aortic complications. Meticulous follow-up and assessment of risk factors can mitigate the adverse aortic events. Hypothesis: We hypothesized that BAV and TAV with AAA can be managed conservatively with acceptable survival, low aortic complication rate, and timely surgery. Methods: From 2016 to 2018, 188 patients were seen for an isolated AAA. 147 patients had two or more CT scans (631-patient-years) which allowed measurement of aortic growth. We used a 1:1 greedy matching algorithm in R to identify similar cohorts of BAV and TAV patients matched by age, sex, hypertension, family history of aortic disease, coronary artery disease, and hyperlipidemia. Univariate and multivariate analysis of the unmatched cohorts were performed. Echocardiogram data was evaluated for each patient. Results: Initial mean AAA diameter was 4.3±0.58 cm (Table 1). The mean time between scans was 4.2 ± 3.3 years. 20 patients had an ascending aortic aneurysm ≥ 5cm with mean diameter 5.2 ± 0.23 cm (range 5.0-6.0 cm). Five patients had an aortic event (1 BAV and 4 TAV). Three of these aortic events lead to patient deaths (1 BAV and 2 TAV), in addition to one death (TAV) unrelated to aortic pathology. From time of enrollment, survival at 10 years was 90 ± 32%. Our model suggests that given the absence of known high risk factors, BAV patients do not have an accelerated ascending or root growth rate in comparison to their TAV counterparts. BAV patients do have higher rates of aortic stenosis (p <.05), a factor that influenced the need for aortic repair. Conclusion: In conclusion, regardless of aortic valve type, the associated AAA has a similar natural history and low adverse event rate. In the absence of risk factors, conservative management of AAA can be accomplished with minimal risk to the patient.

Background In the setting of bicuspid aortic valve (BAV), the assessment of aortic annulus morphology remains poorly defined. Purpose We aim to evaluate the morphology and orientation of the maximum diameter of the aortic annulus in BAV patients using contrast-enhanced computed tomography. Methods We included 159 BAV patients (male: 75%, mean age 55 ±19): 70 with severe aortic stenosis and 89 with ascending aorta enlargement without significant valvulopathy. All patients underwent transthoracic echocardiography (TTE) and contrast-enhanced computed tomography (CT). Results The annulus was asymmetric (eccentricity index: 0.23±0.09) and the Sievers class was not a determinant of annular eccentricity (type 0: 0.26±0.09 vs. type 1: 0.23±0.08, p=0.068). The aortic annulus maximum diameter orientation was evaluated using CT sagittal plane as a reference. This orientation was not dependent on BAV phenotype: horizontal opening: 109.6±28.6° vs vertical opening 111.2 ±28.8°, p=0.87. This is in contrast with the aortic root maximum diameter which is dependent on the BAV phenotype: horizontal or vertical opening: 71.3±35.5° vs. 122.9±35.5°, p<0.0001. (Figure) As a result, diameter obtained in the parasternal long-axis incidence is always the short axis of the ellipse. Using this measure to calculate the annulus area therefore leads to underestimation of annulus area if eccentricity index is not taken into account. The mean difference of the annulus area using TTE vs CT is 142.2mm² i.e., 32% and 0.62cm² i.e., 29% for the aortic valve area. Conclusion orientation of the maximum aortic annulus diameter is orthogonal to the TTE ultrasound beam in BAV patients, irrespective of BAV type. Our results suggest that TTE can lead to an underestimation of annulus area and, consequently, aortic valve area.

Background Transcatheter aortic valve implantation (TAVI) has been shown safe and feasible in patients with bicuspid aortic valve (BAV) morphology. Evaluation of differences in valve morphology and aortic root dimensions in patients with BAV in comparison to patients with tricuspid aortic valve (TAV) is important for the spread of TAVI in patients with BAV. Purpose The present study evaluated the prevalence of BAV subtypes and the differences in valve morphology and aortic root dimensions between BAV and TAV in patients undergoing computed tomography (CT) before TAVI. Methods In five medical centers in Israel, 104 patients (69±13.5 years) with BAV and 105 patients (81±8.22 years) with TAV underwent CT angiography. BAV morphology was defined according to the number of commissures and raphe following Siever's classification. Functional BAV was defined as 3 cusps with focal fusion of 1, 2, or 3 commissures. Aortic root dimensions were measured at the level of the aortic annulus, sinus of Valsalva (SOV), sino-tubular junction (STJ), and ascending aorta (AA). Membranous septum (MS) length was measured in coronal view. The volume and agatston score of aortic valve calcification were evaluated. Results Type 0 account for 22% (23/104), type IA for 58% (60/104), Type IC for 9% (9/104), functional BAV for 11% (12/104). Type IB and II were not found in the studied population. As compared with TAV, patients with BAV have significantly larger aortic annulus area, SOV area, STJ area and AA Area; however, the ellipticity index of aortic annulus, SOV, STJ, and AA were similar. MS length was significantly smaller in patients with BAV compared to patients with TAV (6.4±2.3 mm vs. 8.1±2.7mm; retrospectively; P<0.001) and the volume of aortic valve calcifications was significantly higher in BAV compared to TAV patients: 2.3±1.6 ml3 vs. 1.4±1.2 ml3 retrospectively; P=0.003). Conclusions In Israel, patients with BAV showed more frequently type 1A BAV. BAV patients have larger aortic root dimensions than patients with TAV without difference in regard to the ellipticity index. MS length was smaller and the amount of aortic leaflet calcifications was higher in patients with BAV. These findings may have important impact on procedural outcome.

Bicuspid aortic valve (BAV) is the most common congenital heart disease and is commonly associated with significant ascending aorta dilation. Valve morphology and function have been proposed as potential risk factors; however evaluating their role is difficult, as BAV morphology and valve function are inherently related. Our objective was to determine whether BAV morphology and function are independently associated with ascending aorta dilation in pediatric patients. We performed a multicenter, retrospective, cross-sectional study of pediatric patients with BAV that were followed after 2003. The last patient echocardiogram prior to valve intervention was analyzed for BAV morphology, presence and severity of aortic stenosis (AS) and insufficiency (AI), and aortic root and ascending aorta dimensions. The relationship of potential risk factors to ascending aorta dimensions at different ages was determined using linear regression. Data was obtained from 1725 patients (68% male). The most common BAV morphology was right-left (R-L) coronary cusp fusion (65%) followed by right-non (R-N) fusion (34%) and left-non fusion (1%). Fourteen percent of patients had at least moderate AS and 7% had at least moderate AI. R-L fusion was associated with coarctation (55%), while R-N fusion was less associated with coarctation (19%) and more associated with valve dysfunction (24% and 12% with at least moderate AS and AI). Twenty-seven percent of patients had significant ascending aorta dilation (Z score >3). AS and AI were associated with more significant ascending aorta dilation and a faster Z-score progression over time. R-N fusion was associated with ascending aorta dilation; however, when valves with AS and AI were excluded, there were no differences related to morphology. In patients with no AS or AI, 15% had significant ascending aorta dilation. In this large pediatric cohort of patients with BAV, we show that valve morphology is not independently associated with ascending aorta dilation. Valve dysfunction (both AS and AI) is associated with more significant dilation; however, even in valves with normal function, there is significant ascending aorta dilation. We suggest that there is an inherent arterial abnormality, possibly modified by aortic flow patterns.

Risk of Coronary Obstruction in Redo-Transcatheter Aortic Valve Replacement Between Bicuspid and Tricuspid Aortic Valves.

The ascending aorta dilatation in the bicuspid aortic valve (BAV) patients is often attributed to congenital abnormalities of the aortic wall, but it may be related to hemodynamic disturbances in the course of BAV disease. At present, ascending aortic diameter is used as almost sole but weak predictor of aortic dissection and rupture in BAV. We examined the association between aortic wall mechanics and severity of aortic valve disease including different cusps fusion patterns using conventional echocardiography and tissue Doppler imaging (TDI). We prospectively studied 106 BAV patients: 72 with right-left (R-L) coronary cusp fusion were matched 1:1 to 34 patients with right-noncoronary (R-N) cusp fusion obtaining 34 pairs of patients. Peak systolic radial velocity and acceleration of the ascending aortic wall, measured by TDI, were used as an index of hemodynamic stress imposed on the aorta. Paired analysis showed higher aortic wall radial velocity (4.71 ± 1.61 cm/s vs. 3.33 ± 1.44 cm/s, p = 0.001) and acceleration (1.08 ± 0.46 m/s2 vs. 0.80 ± 0.34 m/s2, p = 0.015) in-R-L compared to R-N fusion. Pearson correlation showed association of ascending tubular aortic diameter with age (r = 0.258, p = 0.012), weight (r = 0.323, p = 0.001), peak aortic valve gradient (r = 0.386, p = 0.0001), aortic root diameter (r = 0.439, p < 0.0001), and R-N fusion pattern (r = 0.209, p = 0.043). Aortic root diameter was related to male gender (r = 0.296, p = 0.003), weight (r = 0.381, p = 0.0001), ascending aortic diameter (r = 0.439, p < 0.0001), and severity of aortic regurgitation (r = 0.337, p = 0.0009). Regional differences in aortic wall motion between different BAV cusp fusion patterns and association of aortic diameters with the severity of aortic valve disease, both suggest a deleterious hemodynamic impact of cusp fusion patterns and aortic valve dysfunction on ascending aortic wall. Assessment of aortic hemodynamic by TDI is feasible and could be potentially used to improve prediction of acute aortic complications, thus helping to establish optimal timing of aortic surgery in BAV patients.

Bicuspid Valve-Related Aortic Disease: Flow Assessment with Conventional Phase-Contrast MRI

Multimodality imaging in bicuspid aortic valve

Background/Objectives: The aim of this study was to evaluate the usefulness of selected predictive parameters obtainable from cardiac multidetector computed tomography for assessing the severity of aortic valve stenosis in patients scheduled for transcatheter aortic valve implantation (TAVI). Methods: A detailed retrospective analysis was performed on 105 patients with a bicuspid aortic valve (BAV), selected from a cohort of 1000 patients with BAV confirmed on ECG-gated CT, and on 105 patients with a tricuspid aortic valve (TAV) matched for sex and age. All patients included in both groups had significant aortic stenosis confirmed on transthoracic echocardiography. Results: Across the entire cohort, a trend toward higher aortic valve calcium scores was observed in patients with bicuspid compared to tricuspid aortic valves (4194.8 ± 2748.7 vs. 3335.0 ± 1618.8), although this difference did not reach statistical significance (p = 0.080). However, sex-stratified analysis showed higher calcium scores in males with BAV than with TAV (5596.8 ± 2936.6 vs. 4061.4 ± 1659.8, p = 0.002), with no significant difference observed among females (p > 0.05). Univariate regression analysis showed that the aortic valve calcium score was the strongest statistically significant predictor of aortic stenosis severity in both groups, with R2 = 0.224 for BAV and R2 = 0.479 for TAV. In the multiple regression model without interaction terms, the explanatory power increased to R2 = 0.280 for BAV and R2 = 0.495 for TAV. Conclusions: In patients scheduled for TAVI, linear regression models assess the severity of aortic stenosis more accurately than any individual predictive parameter obtainable from ECG-CT, with the aortic valve Agatston score emerging as the most reliable single CT-derived predictor of stenosis severity in both TAV and BAV subgroups.

Objective To analyze the echocardiographic features of patients with aortico-left ventricular tunnel (ALVT) and explore the value of echocardiography in the diagnosis of ALVT. Methods Echocardiographic features of 23 patients with ALVT who were admitted to Fuwai Hospital from July 2002 to February 2019 were reviewed and analyzed. The accuracy of echocardiographic diagnosis of ALVT was investigated by comparing the results of echocardiographic diagnosis with intraoperative and cardiac catheterization and CT. The diagnosis methodology was summarized. The reasons for misdiagnosis by echocardiography were analyzed. Results Among the 23 patients with ALVT, 1 case was diagnosed through CT examination prior to the operation and died from the cardiac arrest, 1 case was diagnosed through cardiac catheterization and ventriculography, the remaining 21 patients (91.3%) received the surgical operation and were diagnosed as ALVT. Eighteen patients (78.2%) were accurately diagnosed by echocardiography. One case was misdiagnosed as aortic valve insufficiency, one case was diagnosed as aortic bicuspid valve and regurgitation, two cases misdiagnosed as aortic valve dysplasia and insufficiency, and one case was misdiagnosed as aortic dissection. According to Hovaguimian classification: 8 cases (34.8%) were of type Ⅰ, 12 cases (52.2%) of type Ⅱ, 1 case (4.3%) of type Ⅲ, and 2 cases (8.7%) of type Ⅳ.Different types of patients are treated with different surgical methods. Conclusions ALVT can be accurately diagnosed with echocardiography, but it needs to be differentiated from other aorta to left ventricular shunt or reflux diseases. The establishment of the optimal diagnosis process is helpful to avoid and reduce the missed diagnosis and misdiagnosis to the greatest extent, and provides a reliable basis for the selection of surgical methods. Key words: Echocardiography; Aortico-left ventricular tunnel; Congenital

Entire anatomic area involved in the bicuspid aortic valve (BAV) disease has not been studied well, especially in Asian populations. We investigated prevalence and vascular characteristics of the BAV disease in a Korean population. In a health screening program from 2005 through 2010, 38 BAV patients (BAV group, 0.16 %, 35 males) were isolated among a total of 23,291 persons based on echocardiography. Each BAV patient was matched with three TAV patients (TAV group, n = 114) of the same age, gender, BSA, and hypertension. Using echocardiography and low-dose chest CT scan, diameters of the aortic root to proximal descending aorta (pDA) and pulmonary artery (PA), morphologic types of BAV, and calcification in the aortic root were evaluated in both groups. Diameters of the sinotubular junction and ascending aorta in BAV group were larger than in TAV group (29 ± 7 vs. 27 ± 3 mm, p = 0.046; 42 ± 7 vs. 34 ± 4 mm, p < 0.001, respectively). Diameters of the annulus, sinus of Valsalva, aortic arch, pDA, and PA were not different between two groups. Calcification in the aortic root was approximately seven times more common in BAV group (p < 0.001). Diameters of the aortic root were larger in the R-L type (n = 24) than in the R-N type (n = 11). Prevalence of BAV in a Korean population appears lower than in Western populations. Within the entire anatomic boundaries of BAV, the ascending aorta was predominantly dilated in BAV patients. The R-L type showed more dilatation than the R-N type, not in the ascending aorta but in the aortic root.

Bicuspid aortic valve (BAV) is the most common congenital cardiac malformation and is frequently associated with progressive aortopathy. Subaortic membrane, a discrete form of left ventricular outflow tract (LVOT) obstruction, is uncommon in adults and rarely coexists with BAV outside of complex congenital syndromes. The simultaneous presence of BAV, aortic root dilation, and a subaortic membrane represents an unusual anatomical constellation with important diagnostic and clinical implications. We present the case of a 49-year-old man with no known medical history who developed sudden, painless monocular vision loss and was diagnosed with left central retinal artery occlusion (CRAO). Neurovascular imaging revealed mild carotid atherosclerosis and incidental ascending aortic dilation. Transthoracic echocardiography (TTE) demonstrated a probable BAV, left atrial enlargement, and a suspected subaortic membrane with elevated LVOT gradients. Transesophageal echocardiography confirmed BAV morphology, mild aortic stenosis, and aortic root dilation measuring 4.2 cm, along with severe atherosclerotic plaque in the aortic arch, suggesting an embolic source. This case highlights the importance of comprehensive cardiac evaluation in patients with unexplained embolic events and expands the spectrum of structural abnormalities associated with BAV. Recognition of this rare triad is important for appropriate surveillance, risk stratification, and multidisciplinary management.