Impact of Heart Failure Etiology on Outcomes of Heart Failure with Stable Mid-Range Ejection Fraction

Background Heart failure with mid-range ejection fraction (HFmrEF) of 40-49% is an under-recognized class of CHF. The impact of heart failure etiology in patients with HFmrEF and stable ejection fraction (EF) of one year is unclear. Objectives We hypothesized that patients with ischemic cardiomyopathy (ICMP) and stable mid-range EF (mrEF) and patients with non-ischemic cardiomyopathy (NICMP) and stable mrEF have different mortality and morbidity prognosis. Methods We screened 2593 baseline echo studies at our academic center and identified 724 patients with mrEF. From these patients, we included patients with stable mrEF of 1 year. Student's T-test and chi-square test were used to assess baseline differences between ICMP and NICMP patients. Kaplan Meier survival analysis was conducted and Log-rank p values were calculated to assess the association of different groups with all-cause mortality, cardiac mortality, and heart failure (HF) hospitalizations. Multivariate Cox regression analysis was adjusted for age, gender, race, HTN, DM, COPD, and CKD. Results A total of 132 patients were included in our study. Table 1 summarizes characteristics of patients. Follow up period was 58.7 ± 29.1 months. There was no significant difference in all-cause mortality between ICMP and NICMP patients (figure 1), p-value of 0.223. Cardiac mortality between the two groups was not significantly different, p-value of 0.507 and HF hospitalization rate between them was also not significant, p-value of 0.8. In adjusted model, differences in outcomes remained insignificant. Conclusion We found that patients with ICMP and stable mrEF of 1 year had similar all-cause mortality, cardiac mortality, and HF hospitalization rate compared to patients with NICMP and stable mrEF. Further studies are needed to validate our results.