HFpEF

Picture a balloon whose rubber has gone thick and stiff. It empties just fine when you squeeze it, but it is hard to inflate — you cannot get much air in. HFpEF is heart failure where the ventricle squeezes normally yet has become so stiff that it resists filling, so it cannot take in enough blood between beats.

Formally, HFpEF is heart failure with a left ventricular ejection fraction of 50 percent or higher, where the problem lies in diastole — the relaxation and filling phase. Because the ventricle fills poorly at normal pressures, pressure must rise to push blood in, and that elevated pressure backs up into the lungs, causing breathlessness. It is strongly associated with aging, high blood pressure, obesity, diabetes, and atrial fibrillation, and it is now at least as common as HFrEF.

HFpEF is harder to treat and was long resistant to drugs that help HFrEF. The most important advance is the SGLT2 inhibitor class, which reduces hospitalizations across the ejection-fraction spectrum. Otherwise, management centers on controlling blood pressure, relieving congestion with diuretics, treating obesity and atrial fibrillation, and encouraging exercise.