The Echocardiographic Evaluation of a Bicuspid Aortic Valve: The Effect of Jet Eccentricity and Left Ventricular Outflow Tract Geometry on the Effective Orifice Area

Higher rate of aortic stenosis progression in patients with bicuspid versus tricuspid aortic valve - A single center experience

PURPOSE

We sought to investigate aortic stenosis (AS) progression rate (pr) with the comparison between bicuspid aortic valve (BAV) and tricuspid aortic valve (TAV) morphology.

MATERIALS AND METHODS

We compared ASpr in patients with BAV and TAV examined by transthoracic echocardiography (TTE) in the years 2004-2019.

RESULTS

Data from 363 TTEs in 161 AS patients (median age 70 [61-77] years; 63% men; 25% with BAV; 20% with severe AS) performed at different time points (median time interval 10 months) was analyzed. We assessed changes of AS severity with peak velocity through aortic valve (Vmax), mean/peak pressure gradients (MG/PG), aortic valve area by planimetry and continuity equation (AVAce). We compared pr (defined as parameter change per year) between the BAV and the TAV groups. BAV patients showed faster ASpr with odds ratio 3.467 and 95% confidence intervals 1.36 to 8.86, moreover, expressed as a quicker AVAce decrease 0 (-0.4-0.0) in the BAV vs. 0 (-0.15 - 0.0) cm²/year in the TAV group, p ​= ​0.02. Furthermore, in BAV, female sex was associated with lower ASpr (p ​= ​0.01), and in the whole group a larger aortic diameter was a predictor of faster progression (p ​< ​0.001).

CONCLUSION

The ASpr, expressed as a decrease in the AVAce, was faster in BAV. Moreover, ASpr depends on both: valve morphology being faster in BAV and Vmax increase. Furthermore, the female sex was related to slower pace of AVA reduction in BAV subgroup whereas the larger baseline aortic diameter associated to faster AS progression in the whole studied group.

Diagnostic accuracy study of routine echocardiography for bicuspid aortic valve: a retrospective study and meta-analysis

BACKGROUND

Transthoracic echocardiography (TTE) is the standard procedure to distinguish tricuspid aortic valve (TAV) from bicuspid aortic valve (BAV). Published studies assessed the accuracy of TTE for BAV under ideal conditions. Conversely, we aimed at assessing accuracy of TTE for BAV under routine conditions.

METHODS

This retrospective, cross-sectional study of 216 adults included 132 men aged 62±14 years. Of these, 108 had BAV and 108 were age-matched individuals with TAV. All diagnoses were confirmed at surgery. We assessed TTE in two patient groups. First, in the (I) group of all 216 individuals, where we assessed accuracy for BAV according to the original diagnoses as documented by the primary investigators during original TTE examination. Second, we assessed accuracy for BAV according to expert re-evaluation in (II) all 158 TTE with availability of original recordings. Third, we performed a meta-analysis of published results on the accuracy of TTE for BAV according to PRISMA standards.

RESULTS

Sensitivity, specificity and accuracy of (I) primary investigators was 46.3%, 97.2, and 71.8% as compared to (II) expert re-evaluation with 59.7%, 93%, and 77.8%, respectively. Sensitivity was significantly higher at re-evaluation (P<0.001). TTE at a non-tertiary care center (P=0.012), presence of aortic aneurysm (P=0.001) and presence of severe aortic valve calcification (P=0.003) predicted an inaccurate diagnosis of BAV. Conversely, meta-analysis of published TTE studies identified a pooled sensitivity of 87.7% and a pooled specificity of 88.3% for BAV.

CONCLUSIONS

The current study shows that TTE yields almost ideal diagnostic accuracy when ideal investigators examine ideal patients. However, the study also shows that TTE yields suboptimal diagnostic accuracy under routine conditions. TTE in non-tertiary care settings, concomitant aortic aneurysm, and presence of severe aortic valve calcification predict an inaccurate diagnosis of BAV.