Impaired coronary microcirculation and myocardial function in patients with HFpEF

Abstract Background/Introduction Many studies have demonstrated that coronary microcirculation, assessed by coronary flow reserve (CFR), is impaired in patients with Heart Failure with preserved Ejection Fraction (HFpEF). CFR can be measured non – invasively by Doppler Transthoracic Echocardiography (TTE), in distal left anterior descending artery as the ratio of CFR velocity (CFVR) at rest and after vasodilation agent administration. Echocardiography indices such as Left Atrial Reservoir Strain (LARS) and E/E’ are used for the evaluation of diastolic function and contribute to the diagnosis of patients with HFpEF. Left Ventricular (LV) systolic function can be assessed by the measurement of Global Longitudinal Strain (GLS). Purpose The aim of the study is to investigate the association between impaired coronary microcirculation and myocardial diastolic and systolic dysfunction in HFpEF patients. Methods 60 subjects without known coronary artery disease (CAD) were enrolled in the study (30 patients with HFpEF and 30 control subjects). All patients underwent clinical evaluation, Transthoracic (TTE), Adenosine Stress Echocardiography (ASE) and coronary flow reserve (CFR) measured by using Doppler echocardiography. Patients with HFpEF were subdivided into the CFR < 2 (n = 14) and the CFR ≥2 (n = 16) groups. Results Statistical analysis revealed significant difference between patients with HFpEF and control group concerning CFR (median CFR: 2.2 vs 2.8, p-value = 0.001), GLS (median GLS: -18 % vs -19.7%, p-value = 0.001), LARS (median LARS: 22% vs 32%, p-value< 0.001) and E/E’ (median E/E’: 9.5 vs 8, p-value = 0.015).In addition, CFR