Leg strength and incidence of heart failure in patients with acute coronary syndrome.

AIMS: The risk of developing heart failure (HF) after acute coronary syndrome (ACS) remains high. It is unclear whether skeletal muscle strength, in addition to existing risk factors, is a predictor for developing HF after ACS. We aimed to clarify the relationship between quadriceps isometric strength (QIS), a skeletal muscle strength indicator, and the risk of developing HF in patients with ACS.

METHODS AND

RESULTS

We included 1053 patients with ACS without a prior HF or complications of HF during hospitalization. The median (interquartile range) age was 67 (57-74) years. The patients were classified into two groups-high and low QIS-using the sex-specific median QIS. The endpoint was HF admissions. During a mean follow-up period of 4.4 ± 3.7 years, 75 (7.1%) HF admissions were observed. After multivariate adjustment, a high QIS was associated with a lower risk of HF [hazard ratio: 0.52, 95% confidence interval (CI): 0.32-0.87]. Hazard ratio (95% CI) per 5% body weight increment increase of QIS for HF incidents was 0.87 (0.80-0.95). Even when competing risks of death were taken into account, the results did not change. The inclusion of QIS was associated with increases in net reclassification improvement (0.26; 95% CI: 0.002-0.52) and an integrated discrimination index (0.01; 95% CI: 0.004-0.02) for HF.

CONCLUSION

The present study showed that a higher level of QIS was strongly associated with a lower risk of developing HF after ACS. These findings suggest that skeletal muscle strength could be one of the factors contributing to the risk of developing HF after ACS.