Heart failure categories Damage to heart muscle (myocardium), such as occurring following myocardial infarction or cardiomyopathy, compromises the heart's performance as an<unk> ficient pump and may reduce<unk> . Such reduction in the<unk>  can manifest itself as heart failure. The 2016 European Society of Cardiology guidelines for the diagnosis and treatment of acute and chronic heart failure subdivided heart failure into three categories on the basis of LVEF: # normal or preserved LVEF ≥50% (HFpEF) # moderately reduced LVEF in the range of 40–49% (HFmrEF) # reduced LVEF <40% (HFrEF) A chronically low<unk>  less than 30% is an important threshold in qualification for disability benefits in the US.
Ejection fraction
Coronary flow reserve
Stress–strain index
Transpulmonary pressure
Coronary perfusion pressure
Rate pressure product
Pulmonary wedge pressure
End-systolic volume