The following is a summary of “Posterior Wall Thickness Associates With Survival Following Septal Myectomy for Obstructive Hypertrophic Cardiomyopathy” published in the November 2022 issue of Heart Failure by Sun et al.

The prognostic significance of left ventricular (LV) posterior wall thickness (PWT) has not been examined in adults; however, it is a predictor of sudden cardiac death in pediatric patients with hypertrophic cardiomyopathy (HCM). Therefore, this research aimed to determine if left ventricular (LV) posterior wall thickness (PWT) correlated with long-term survival in adults undergoing septal myectomy for obstructive HCM. Strategies 2,418 patients with transaortic septal myectomy for obstructive HCM were included in this single-center study.

The average preoperative PWT was 13 (11-15) mm. Patients with a PWT>13 mm had a higher prevalence of systemic hypertension (55.4% vs. 49.1%; P=0.002) and a higher median body mass index (30.8 [IQR: 27.1-35.1] kg/m2 vs. 29.6 [IQR: 26.1-33.9] kg/m2; P<0.001). Septal thickness (median: 21 [IQR: 18-24] mm vs. 19 [IQR: 17-22] mm; P<0.001), maximum instantaneous left ventricular outflow tract (LVOT) gradient at rest (median: 67 [IQR: 36-96] mm Hg vs. 47 [IQR: 19-79] mm Hg), and the likelihood of moderate or greater mitral valve regurgitation (54.3% vs. 47.3%). 

New York Heart Association functional class did not correlate with PWT in terms of the severity of limitations (P=0.674). However, high PWT was an independent risk factor for death after septal myectomy, even after controlling for other factors. In addition to septal thickness and left ventricular outflow tract (LVOT) gradient severity, postoperative PWT has been found to be an independent predictor of decreased long-term survival following septal myectomy.