Alterations in Layer-Specific Left Ventricular Global Longitudinal and Circumferential Strain in Patients With Aortic Stenosis: A Comparison of Aortic Valve Replacement versus Conservative Management Over a 12-Month Period

Abstract

Impairment in left ventricular (LV) systolic strain in aortic stenosis (AS) is well documented. However, alterations in layer-specific LV global longitudinal strain (GLS) and global circumferential strain (GCS) and their recovery following surgical aortic valve replacement (AVR) have not been established. The aim of this study was to examine layer-specific changes in GLS and GCS in patients with AS undergoing AVR and compare these patients with those managed conservatively over 12months. Eighty-six patients (mean age, 68.8±12years; 60 men) with AS (19 mild, 15 moderate, and 52 severe) were prospectively recruited. Patients with coronary disease or other significant valvular disease were excluded. Forty patients (46.5%) with severe AS underwent AVR. All patients underwent baseline echocardiography. Patients managed conservatively underwent follow-up echocardiography at 12months. Patients undergoing AVR underwent follow-up echocardiography at 1week and 3, 6, and 12months after AVR. There was worsening in subendocardial but not subepicardial or transmural GLS even in mild AS (-20.9±1.0% vs -20.6±0.8%, P=.012). In moderate AS, worsening in subendocardial (-19.6±0.9% vs -18.2±1.5%, P=.003), subepicardial (-14.9±1.0% vs -13.8±1.2%, P=.004), and transmural (-17.1±0.9% vs -15.8±1.3%, P=.03) GLS and a trend toward significant worsening in subendocardial GCS (-29.8±5.16% vs -27.5±5%, P=.054) were seen. Conservatively managed patients with severe AS had significant worsening in subendocardial (-16.1±1.6% vs -13.9±2.6%, P=.021), subepicardial (-11.6±1.1% vs -10.1±2.1%, P=.027), and transmural (-13.6±1.3% vs -11.8±2.3%, P=.02) GLS and subendocardial (-24.9±3.6% vs -20.8±4.5%, P=.002) and transmural (-16.9±1.7% vs -14.3±3.5%, P=.04) GCS on follow-up. Patients after AVR demonstrated significant improvement in GLS (from 3months) and GCS (from 6months) in both myocardial layers. Patients with AS managed conservatively had worsening of GLS over 12months despite preserved LV ejection fraction, detected earliest in the subendocardial layer. GCS became progressively impaired in moderate and severe AS. Improvement in LV strain after AVR was seen earlier with GLS (from 3months) than with GCS (from 6months) in both myocardial layers.