Evaluation of Left Ventricular Relaxation and Filling Pressures in Obstructive Hypertrophic Cardiomyopathy: Comparison between Invasive Hemodynamics and Two-Dimensional Speckle Tracking

Background: Hypertrophic cardiomyopathy (HCM) is usually associated with marked diastolic dysfunction, characterized by impaired myocardial relaxation and increased myocardial stiffness. The noninvasive evaluation of diastolic function in these patients remains a challenge since usual methods have shown a modest correlation with invasive measurements of left ventricular (LV) relaxation and filling pressures. Methods and Results: We retrospectively analyzed 44 patients with obstructive HCM who underwent cardiac catheterization and echocardiography performed within 48 hours. Standard echocardiographic diastolic parameters and systolic and diastolic myocardial mechanics (including longitudinal and circumferential strain S] and strain rate Sr]), LV rotation, and early reverse rotation rate (fraction of early apical reverse rotation FEARR]) were correlated with diastolic hemodynamic indices. Estimated LA pressure by echo and the LV end-diastolic pressure (LVEDP) or the LV pre-A pressure did not correlate. Longitudinal strain was low and circumferential strain was abnormally higher than normal. FEARR and negative dp/dt inversely correlated (R =-0.57, P = 0.0001), and early diastolic Sr to systolic Sr ratio (SrE/SrS) correlated with the LVEDP (r = 0.61, P < 0.0001). Furthermore, a SrE to SrS ratio ≥0.79 had a sensitivity of 87% and a specificity of 75% for predicting elevated LVEDP (≥15 mmHg). Average circumferential strain rate during atrial contraction and LV pre-A pressure (r =-0.62, P < 0.001) inversely correlated. Conclusions: FEARR is decreased in HCM and appears to be a good measure of diastolic dysfunction. Myocardial mechanics can be used to assess LV relaxation and filling pressures in patients with obstructive HCM.