Cardiac Magnetic Resonance Left Atrial Strain in the Prediction of Death, Ischemic Stroke, and Heart Failure

Abstract

Background To determine the prognostic value of left atrial strain (LAS) using cardiac magnetic resonance for predicting death, heart failure, and ischemic stroke in patients with known or suspected coronary artery disease with preserved left ventricular systolic function and no prior history of ischemic stroke, heart failure, or atrial fibrillation. Methods and Results This retrospective cohort analysis included patients referred for stress cardiac magnetic resonance or myocardial viability studies between September 2017 and December 2019. Patients with impaired left ventricular systolic function (<50%) or a history of atrial fibrillation, stroke, or heart failure were excluded. A multivariable Cox model assessed the prognostic value of LAS, with the primary outcomes being the composite outcomes of all‐cause death, ischemic stroke, and heart failure. A total of 2030 participants were included in the study. The average LAS was 24.1±8.5%; 928 had LAS <23%, and 1102 had LAS ≥23%. The mean follow‐up duration was 39.9±13.6 months. There were 49 deaths (2.4%), 32 ischemic strokes (1.6%), and 34 heart failure events (1.7%). Patients with LAS <23% were at greater risk for composite outcome, with an adjusted hazard ratio of 2.31 (95% CI, 1.50–3.55). Conclusions LAS by cardiac magnetic resonance has an independent and incremental prognostic value for death, ischemic stroke, and heart failure in patients with preserved left ventricular systolic function. This prognostic value is observed after adjusting for clinical and cardiac magnetic resonance parameters, including left ventricular systolic function, late gadolinium enhancement, and left atrial volume index.