The Role of Clefts and Cleft-Like Indentations in Mitral Regurgitation Etiology Detected by Three-Dimensional Echocardiography in Patients with Hypertrophic Cardiomyopathy.

Objective: Mitral regurgitation (MR) is a critical determinant in patients with hypertrophic cardiomyopathy (HCM). Three-dimensional (3D) echocardiography has transformed the imaging of the mitral valve by enabling real-time, direct visualization. This study aims to determine the frequency of clefts and cleft-like indentations (CLIs) and assess their contribution to MR in HCM patients.

Method: A total of 50 patients with HCM and moderate or severe MR who underwent 3D transesophageal echocardiography (TEE) were enrolled. For the control group, 200 patients with moderate or severe MR but without HCM were selected. The two groups were compared in terms of demographic characteristics, echocardiographic findings, and cardiac magnetic resonance imaging results.

Results: Patients with HCM were younger and had higher regurgitant volumes and effective regurgitant orifice areas compared to the control group. Clefts or CLIs were present in 14 patients (28%) in the HCM group compared to 31 patients (15.6%) in the control group (P = 0.041). Evaluation of MR jet direction in relation to the presence of clefts or CLIs revealed a significant association between anteriorly directed jets and the presence of clefts (P = 0.003).

Conclusion: In this study, the frequency of clefts or CLIs was higher in patients with HCM compared to the control group. Clefts influence the direction of MR jets (anteriorly), whereas CLIs do not. 3D-TEE can aid in the differential diagnosis of HCM in patients with anteriorly directed MR jets. However, using 3D-TEE to identify CLIs alone has no significant impact on the management of MR.