Early Diastolic Release Flow Is a Sensitive Early Marker for Left Ventricular Apical Aneurysm in Patients with Hypertrophic Cardiomyopathy

Background: Left ventricular apical aneurysm (LVAA) is a rare but important finding in hypertrophic cardiomyopathy (HCM) that is associated with increased risk for ventricular arrhythmia and thromboembolism. Doppler evidence of basally-directed flow during early diastole representing the release of pressurized blood volume during ventricular relaxation may serve as a more sensitive marker for LVAA than standard 2D echocardiography. Methods: HCM patients with LVAA and available echocardiography were enrolled. Clinical echocardiographic studies were assessed for evidence of early-diastolic release flow (EDRF), defined as basally-directed flow identified in early diastole. Sensitivity of EDRF for detection of LVAA was compared to alternative imaging modalities. In patients with repeat echocardiography at 5-years, changes in aneurysm size and EDRF flow characteristics were assessed. Results: 51 HCM patients with LVAA were enrolled. While standard 2d echocardiography had low sensitivity for LVAA (25/51, 49%), EDRF was detected in 46/51 patients (90%). In the subset of patients for whom LVAA was missed on 2D echocardiography, sensitivity of EDRF remained high (26/26, 100%). In patients with 5-year longitudinal imaging (n=16, 31%), mean aneurysm size increased (17mm vs 25mm, p-value=0.0002) and LVEF decreased (62% vs 54%, p-value=0.002); EDRF visualization was lost in 4 (25%). Specificity of EDRF for LVAA diagnosis was 96.4% in control patients with apical variant HCM. Conclusions: EDRF is a sensitive early echocardiographic marker of LVAA that is most useful for LVAA that would otherwise be missed on standard 2D echocardiography. Identification should prompt definitive testing with CMR or contrast-enhanced echocardiography.