Real-world Accuracy of Transthoracic Echocardiography in Diagnosing Bicuspid Aortic Valve Morphology: A Single Center UK Experience

Objectives: The aim of this study was to compare the diagnostic accuracy of Transthoracic Echocardiography (TTE) in assessing Bicuspid Aortic Valve (BAV) morphology. Methods: Case notes of 408 patients (>18 years old) undergoing elective Aortic Valve (AV) surgery over a 2-year period were retrospectively reviewed. Aortic valve data was collected from preoperative TTE reports and intraoperative records. The diagnostic accuracy of TTE for identifying AV morphology was assessed using intraoperative findings as the gold standard. One-hundred-and-eighty-nine (46.3%) patients had a recent TTE with complete morphological assessment of the AV and an operation note documenting AV morphology. Cases that were ‘unable to be determined’ on TTE were included as false negatives. Results: TTE correctly identified AV morphology in 165 of the patients, equating to an accuracy of 79.1% (sensitivity = 72.4%, specificity = 87.3%). For BAV patients alone, accuracy was 81.3% (sensitivity = 65.8%, specificity = 90.0%), and for Tricuspid Aortic Valve (TAV) patients, accuracy was 77.1% (sensitivity = 75.5%, specificity = 81.4%). There was no significant difference in diagnostic accuracy of TTE for BAV and TAV (p = 0.464), nor was there any difference between valve calcification (p = 0.196) and functional disease (p = 0.088). Conclusion: Our data suggests that identification of BAV from TTE requires expertise and therefore it is operator dependent. A larger study is required to confirm our findings.