Usefulness of Left Ventricular Strain by Cardiac Magnetic Resonance Feature-Tracking to Predict Cardiovascular Events in Patients With and Without Heart Failure.

There is controversy regarding the utility of left ventricular (LV) mechanics assessed by feature-tracking steady-state free-precession (FT-SSFP), a readily implementable technique in clinical practice. In particular, whether LV mechanics assessed by FT-SSFP predicts outcomes in subjects with heart failure (HF) with reduced ejection fraction (HFrEF), with preserved ejection fraction (HFpEF), or without HF is unknown. We aimed to assess whether LV mechanics measured with FT-SSFP cine magnetic resonance imaging (MRI) predicts adverse outcomes. We prospectively enrolled 612 adults without HF (n = 402), with HF with reduced ejection fraction (HFrEF; n = 113), or HFpEF (n = 97) and assessed LV strain using FT-SSFP cine MRI. Over a median follow-up of 39.5 months, 75 participants had an HF admission, and 85 died. In Cox proportional hazards models, lower global longitudinal (Standardized hazard ratio 1.56, 95% confidence interval [CI] 1.22 to 2.00, p = 0.0004), circumferential (Standardized HR 1.46, 95% CI 1.08 to 1.95, p = 0.0123), and radial strain (Standardized HR 0.59, 95% CI 0.43 to 0.83, p = 0.0019) were independently associated with the composite endpoint, after adjustment for HF status, LV ejection fraction (LVEF), age, sex, ethnicity, body mass index, systolic and diastolic blood pressure, hypertension, diabetes, coronary artery disease, and glomerular filtration rate. Furthermore, global longitudinal strain stratified the risk of adverse outcomes across tertiles better than LVEF. In analyses that included only participants with a preserved LVEF, systolic radial, circumferential and longitudinal strain were independently predictive of adverse outcomes. We conclude that LV longitudinal, circumferential and radial strain measured using FT-SSFP cine MRI (a readily implementable technique in clinical practice) predict the risk of adverse events, independently of LVEF.