Results:

The final study cohort was comprised of 1,012 patients (505 ischemic and 507 nonischemic), of whom 133 died during a median follow-up of 4.4 years. The mean age of the study population was 60 ±16 years. Sixty-five percent of patients were male, and 31% had diabetes mellitus. The mean EF was 33.7 ± 10.0%. Mean GLS for the population was -10.9%. Median GLS was -11.0% (interquartile range, -7.8 to -14.0%). Using Kaplan-Meier analysis, the investigators found that the risk of death increased significantly with worsening GLS tertiles (log-rank p < 0.0001). There was an 89.1% increased risk of death with each 1% worsening in GLS after adjusting for clinical and imaging risk factors including age, body mass index, diabetes, hyperlipidemia, left ventricular end-diastolic volume index, EF, and late gadolinium enhancement (LGE) (hazard ratio [HR], 1.891 per %; p < 0.001). There was a significant improvement in the C-statistic with addition of GLS in this model (0.628-0.867; p < 0.0001). Continuous net reclassification improvement was 1.148 (95% confidence interval, 0.996-1.318). In patients with ischemic cardiomyopathy, each 1% worsening in GLS was associated with a 94.2% increased risk of death after adjustment for clinical and imaging risk factors (HR, 1.942 per %; p < 0.001). Similarly, in patients with nonischemic dilated cardiomyopathy, GLS remained significantly associated with death after adjustment for clinical and imaging risk factors (HR, 2.101 per %; p < 0.001).