FISDAP Cardiology Practice Test

Diastolic heart failure, also known as heart failure with preserved ejection fraction (HFpEF), is characterized primarily by the heart muscle's inability to relax properly. In this condition, the heart chambers become stiff due to structural changes, which often occur with aging, hypertension, or conditions such as diabetes. As a result, the heart cannot fill adequately during the diastolic phase of the cardiac cycle, leading to inadequate blood flow to the body despite a preserved ejection fraction.

In contrast, the other options describe different mechanisms or types of heart dysfunction. A scenario where heart muscles contract too quickly would typically relate to tachycardia or arrhythmias rather than diastolic failure. Valvular defects can contribute to heart failure types but are not a defining characteristic specific to diastolic heart failure. An overactive pumping mechanism does not accurately describe the dysfunction seen in diastolic failure, as the issue lies in filling rather than excessive contraction. Overall, the defining feature of diastolic heart failure is the stiffness and inadequate relaxation of the heart muscle.