Incremental prognostic value of left atrial strain in patients with heart failure

AIMS: The present study aimed to evaluate the prognostic value of atrial strain and strain rate (SR) parameters derived from cardiac magnetic resonance (CMR) feature tracking (FT) in patients with ischaemic and non‐ischaemic dilated cardiomyopathy with heart failure with reduced ejection fraction (HFrEF) but without atrial fibrillation. METHODS AND RESULTS: A total of 300 patients who underwent CMR with left ventricular ejection fraction (LVEF) ≤ 40% and ischaemic or non‐ischaemic dilated cardiomyopathy were analysed in this retrospective study. Major adverse cardiac events (MACEs) include cardiovascular death, heart transplantation, and rehospitalization for worsening HF. Ninety‐four patients had MACEs during median follow‐up of 3.84 years. Multivariate Cox regression models adjusted for common clinical and CMR risk factors detected a significant association between LA‐εs and MACE in ischaemic (HR = 0.94/%; P = 0.002), non‐ischaemic dilated cardiomyopathy (HR = 0.88/%; P = 0.001), or all included patients (HR = 0.87; P < 0.001). LA‐εs provided incremental prognostic value over conventional outcome predictors (Uno C statistical comparison model: from 0.776 to 0.801, P < 0.0001; net reclassification improvement: 0.075, 95% CI: 0.0262–0.1301). Kaplan–Meier analysis revealed that the risk of MACE occurrence increased significantly with lower tertiles of left atrial reservoir strain (LA‐εs) (log‐rank P < 0.0001). Patients in the worst LA‐εs tertile faced a significantly increased risk of MACEs irrespective of late gadolinium enhancement (LGE) (log‐rank P < 0.0001). CONCLUSIONS: LA‐εs derived from CMR FT has a significant prognostic impact on patients with ischaemic or non‐ischaemic dilated cardiomyopathy, incremental to common clinical and CMR risk‐factors.