NBME Comprehensive Basic Science Examination (CBSE) Practice Exam

In diastolic heart failure, the heart’s ability to contract and eject blood is preserved, while filling is impaired. This means the ejection fraction remains normal or near-normal because systolic function is intact even though the ventricle is stiff and unloads less efficiently during diastole. The problem lies with relaxation and compliance, leading to higher filling pressures rather than reduced pumping capacity. So the parameter that stays preserved is the left ventricular ejection fraction.