Native skeletal muscle T1-time on cardiac magnetic resonance: A predictor of outcome in patients with heart failure with preserved ejection fraction.

• Skeletal muscle is displayed and easily quantifiable on standard CMR T1-maps. • High native skeletal muscle T1 times are linked to a more unfavorable prognosis. • Native skeletal muscle T1 time may serve as a risk stratification marker in HFpEF. Heart failure with preserved ejection fraction (HFpEF) is associated with heart failure (HF) hospitalizations and death. Previous studies have shown that altered muscle composition is associated with higher risk of adverse outcome in HFpEF patients. The purpose of our study was to investigate the association between skeletal muscle composition, as measured by skeletal muscle T1-times on cardiac magnetic resonance (CMR) imaging, and adverse outcome. We measured skeletal muscle T1-times of the back muscles on standard CMR images in a prospective cohort of HFpEF patients. Cox regression models were used to test the association of skeletal muscle T1-times and adverse outcome defined as hospitalization for HF and/or cardiovascular death. We included 101 patients (mean age 72±7 years, 71 % female) in our study. The median skeletal muscle T1-times were 842 ms (IQR 806–881 ms). In univariate analysis high muscle T1-time was associated with adverse outcome (HR=1.96 [95 % CI, 1.31–2.94] per every 100 ms increase; p =.001). After adjustment for age, sex, body mass index, left- and right ventricular ejection fraction, N-terminal pro-brain natriuretic peptide and myocardial native T1-times, native skeletal muscle T1-time remained an independent predictor for adverse outcome (HR=1.94 [95 % CI, 1.24–3.03] per every 100 ms increase; p =.004). In patients with HFpEF, high skeletal muscle T1-times on standard CMR scans are associated with higher rates of HF hospitalizations and cardiovascular death. Condensed abstract: Skeletal muscle abnormalities are common in patients with heart failure with preserved ejection fraction (HFpEF). The present study evaluates skeletal muscle composition, as quantified by native skeletal muscle T1-times of the back muscles on standard cardiac magnetic resonance imaging, and assessed the association with adverse outcome, defined as hospitalization for heart failure and/or cardiovascular death. In a prospective cohort of 101 patients with HFpEF, we found that high native skeletal muscle T1-times are associated with an increased risk for adverse outcome. These findings suggest that native skeletal muscle T1-time may serve as marker for improved risk prediction. High skeletal muscle T1-time is associated with highest risk of adverse cardiovascular events including heart failure hospitalizations and cardiovascular death 101 patients with HFpEF underwent CMR for measurement of skeletal muscle T1-time of the back muscles (green arrows on panel 3) using T1-mapping to assess muscle tissue. The right panel shows time-to-event curves of the study cohort for the combined endpoint of HF hospitalizations and/or cardiovascular death, stratified by skeletal muscle T1-time median. Patients with high skeletal muscle T1-time (purple line), suggesting that inflammation and fibrosis are present, had a higher risk for adverse outcome compared to patients with a low skeletal muscle T1-time (blue line). CMR, cardiac magnetic resonance; HF, heart failure; HFpEF, heart failure with preserved ejection fraction. [Display omitted] [ABSTRACT FROM AUTHOR]