Usefulness of left ventricular mechanical dyssynchrony for predicting atrial fibrillation and adverse outcomes following first atrial fibrillation event

Abstract Background Left ventricular mechanical dyssynchrony (LVMD) has shown to predict many cardiovascular outcomes including ventricular arrhythmias. Our hypothesis is that LVMD can reveal early atrial dysfunction. Purpose The aim of this study was to investigate whether LVMD can be used to predict atrial fibrillation (AF) and adverse outcomes following first AF event in individuals from the general population. Methods A total of 3785 individuals (mean age 55±17 years, 57% women) from the general population free of AF, heart failure (HF) and prior stroke had an echocardiographic examination performed including two-dimensional speckle tracking echocardiography. LVMD was calculated as the standard deviation of the regional time-to-peak strain from the three apical views. The primary endpoint was AF, and the secondary endpoint was complicated AF as assessed by the occurrence of either stroke or HF after the diagnosis of AF. Results During a median follow-up of 5 years (interquartile range, 4.4-6.2 years), 142 (4%) individuals were diagnosed with AF, and of these 22 (15%) individuals developed HF or stroke. LVMD was a univariable predictor of AF (per 10ms increase: HR 1.03; 95% CI (1.02-1.05), p<0.001, Figure). The association remained significant even after multivariable adjustment for age, sex, body mass index, diabetes, hypertension, heart rate, previous ischaemic heart disease, systolic blood pressure, diastolic blood pressure, smoking, left ventricular ejection fraction, global longitudinal strain, left atrial volume index (LAVI), and E/e’ (per 10ms increase: HR 1.02; 95% CI (1.00-1.04), p=0.042). LVMD also predicted complicated AF, and the association remained significant even after multivariable adjustment (per 10ms increase: HR 1.05; 95% CI (1.01-1.09), p=0.026). Furthermore, LVMD provided incremental prognostic information over the LAVI with regard to predicting AF (Harrell’s C-statistics 0.66 vs. 0.70, p=0.012). Conclusion In a low-risk general population, LVMD provides prognostic information on the risk of AF. Additionally, LVMD can identify individuals with complicated AF defined as occurrence of either stroke or HF following the diagnosis of incident AF. Furthermore, LVMD provides incremental prognostic information over the LAVI in predicting AF.