Association of Coronary Microvascular Dysfunction with Heart Failure Hospitalizations and Mortality in Heart Failure with Preserved Ejection Fraction - a follow-up in the PROMIS-HFpEF study.

Abstract BACKGROUND Coronary microvascular dysfunction (CMD) is common in heart failure with preserved ejection fraction (HFpEF). We assessed the association of CMD with hospitalization and mortality in HFpEF. METHODS We assessed one-year outcomes in patients from the PROMIS-HFpEF study, a prospective observational study of patients with chronic stable HFpEF undergoing coronary flow reserve (CFR) measurements. Outcomes were 1) time to CV death/first HF hospitalization 2) CV death/recurrent HF hospitalizations 3) all-cause death/first HF hospitalization and 4) first and 5) recurrent all-cause hospitalizations. CMD was defined as CFR RESULTS Of 263 patients enrolled, 257 were evaluable at one year. Where CFR was interpretable (n=201) CMD was present in 150 (75%). Median follow-up was 388 days (Q1;Q3 365;418). The outcome of CV death/first HF hospitalization occurred in 15 patients (4 CV deaths). The incidence rate was in CMD 96/1000 (95% CI 54-159) vs. non-CMD 0/1000 person-years (0-68); p=0.023 and remained significant after accounting for selected clinical variables. In patients with CMD, incidence rates were significantly higher also for CV death/recurrent HF hospitalizations, all-cause death/first HF, and recurrent but not first all-cause hospitalization. CONCLUSIONS In this exploratory assessment of the prognostic role of CMD in HFpEF, CMD was independently associated with primarily CV and HF specific events. The high prevalence of CMD and its CV and HF specific prognostic role suggest CMD may be a potential treatment target in HFpEF.