Ventricular Mechanical Asynchrony in Patients with Different Degrees of Systolic Dysfunction : Results from AVE Registry by the Italian Society of Cardiovascular Echography (SIEC).

Objective: The aim of the study was to compare the prevalence of interventricular and intraventricular asynchrony in patients with different degrees of left ventricular (LV) dysfunction. Methods: We enrolled 182 patients (male 79%, mean age 64 } 11 years) with LV ejection fraction (EF) < 50% and identified two groups: Group A (n = 79) with mild-to-moderate LV dysfunction (EF between 36% and 49%) and Group B (n = 103) with severe dysfunction (EF ≤ 35%). An echocardiogram was performed in all patients and a delay longer than 40 msec in the time difference between the aortic and pulmonary preejection intervals was considered as an index of interventricular asynchrony. The electromechanical delays were assessed by pulsed tissue Doppler technique. A time difference between the earliest and the latest segment greater than 40 msec was considered the cutoff for intraventricular asynchrony. The sum of asynchrony was calculated by adding to the LV intraventricular delay the delay between the lateral basal right ventricular segment and the most delayed LV basal segment. Results: The prevalence of interventricular asynchrony was lower among Group A patients (19.8% vs. 37.9%; P = 0.007) while the prevalence of intraventricular asynchrony did not differ between groups (32.9% vs. 44% in Group A and Group B respectively; P = 0.18). The sum of asynchrony (cutoff >102 msec) did not differ between groups either (29.9% vs. 35.9%; P = 0.39). Conclusions: The prevalence of intraventricular asynchrony is independent of the LV systolic dysfunction severity. This could indicate the potential role of cardiac resynchronization therapy in patients with mild-moderate systolic dysfunction.