Coronary microvascular dysfunction is associated with exertional haemodynamic abnormalities in patients with heart failure with preserved ejection fraction

Aims This study uniquely explored the relationship between coronary microvascular function and exercise haemodynamics using concurrent invasive testing. Methods and results Fifty-one consecutive patients with unexplained cardiac exertion symptoms, non-obstructive coronary artery disease and normal left ventricular ejection fraction (>50%) underwent haemodynamic exercise assessment and concurrent coronary reactivity testing. Heart failure with preserved ejection fraction (HFpEF) was defined as a pulmonary arterial wedge pressure (PAWP) >= 15 mmHg at rest and/or >= 25 mmHg at peak exercise. Endothelium-independent coronary microvascular dysfunction (CMD) was defined as a coronary flow reserve (CFR)