Diastole

The time during which the ventricular heart muscle relaxes after each contraction, between each heart beat.

Glossary: Austin Flint Murmur
Glossary: Diastolic Dysfunction
Impaired relaxation and filling of the left ventricle between heartbeats, causing the symptoms of heart failure despite a normal ejection fraction. Underlies HFpEF. Common causes include ageing, hypertension, diabetes, and obesity. Diagnosed by echocardiogram Doppler assessment. Managed with blood pressure control, diuretics, and SGLT2 inhibitors.
Glossary: Graham Steell Murmur