Prognostic Importance of Left Ventricular Mechanical Dyssynchrony in Predicting Cardiovascular Death in the General Population

Abstract

Background: Cardiovascular death (CVD) is a leading cause of death and constitutes a major burden on society. Left ventricular mechanical dyssynchrony (LVMD), evaluated as SD of time to peak regional longitudinal strain, is a capable predictor of many cardiovascular outcomes related to CVD, including ventricular arrhythmias, but the prognostic utility of LVMD in the general population is unknown. Hence, this study sought to determine the prognostic value of LVMD in the general population in predicting CVD.

Methods and results: A total of 1138 participants underwent a general health examination and an echocardiographic examination including speckle tracking analysis with subsequent calculation of LVMD from time-to-peak regional strain. Primary end point was CVD, and secondary end point was noncardiovascular death. Follow-up was 100%. During a median follow-up of 11.1 years (interquartile range: 10.2-11.3 years), 62 participants suffered CVD (5.5%) while 131 participants experienced noncardiovascular death (11.5%). LVMD was an independent predictor of CVD (subdistribution hazard ratio, 1.04; 95% CI, 1.01-1.06; P=0.004, per 10-ms increase) in competing risk regression treating noncardiovascular death as a competing risk and retained prognostic capability after extensive multivariable adjustment. LVMD was not a significant predictor of noncardiovascular death. LVMD added incremental prognostic information in predicting CVD beyond the Systematic Coronary Risk Evaluation risk chart and a modified version of the American College of Cardiology/American Heart Association Pooled Cohort Equation.

Conclusions: Left ventricular mechanical dyssynchrony adds incremental prognostic information in addition to established risk factors in prediction of CVD in individuals from the general population without atrial fibrillation and significant valvular disease.

Keywords: arrhythmias, cardiac; death, sudden, cardiac; echocardiography; prognosis; ventricular fibrillation.