Thigh Intramuscular Fat on Prognosis of Patients With Nonischemic Cardiomyopathy.

Skeletal muscle atrophy is an independent prognostic predictor for patients with chronic heart failure, and the concept of sarcopenia is drawing attention. Furthermore, the importance of not only muscle mass but also ectopic fat has been pointed out. However, there is a lack of consensus on the implications of ectopic fat for the prognosis in patients with nonischemic cardiomyopathy. We investigated whether ectopic fat in the thigh affects the prognosis of nonischemic cardiomyopathy. This prospective study recruited 145 patients diagnosed with nonischemic cardiomyopathy between September 2017 and January 2020. Finally, 93 patients with a reduced ejection fraction were enrolled. The clinical end points were cardiovascular death or unexpected rehospitalization because of a cardiac event. Using computed tomography, the percentage of intramuscular fat (%IMF) in the thigh was measured in all patients. Patients were divided into 2 groups based on the median %IMF. The results of Spearman's correlation coefficient analysis revealed a correlation among %IMF and peak oxygen uptake (Spearman r = -0.221, p = 0.036). Kaplan-Meier analysis results showed significantly higher risk of adverse events in the high %IMF group (log-rank p = 0.013). Multivariate Cox regression analysis results revealed the %IMF as an independent factor for adverse events (hazard ratio 1.361; 95% confidence interval 1.043 to 1.745; p = 0.018). In conclusion, %IMF may have adverse consequences such as increased cardiac events in patients with nonischemic cardiomyopathy with a reduced ejection fraction.