During which part of the cardiac cycle does isovolumetric relaxation occur?
Show answer and explanation
Correct answer: After aortic valve closes, before mitral opens
Isovolumetric relaxation follows aortic valve closure and precedes opening of the mitral valve; ventricles relax, pressure falls, but volume remains constant because all valves are closed.
Keep practicing
More Cardiac Cycle and Hemodynamics questions
- Which of the following best reflects the relationship between end-diastolic volume (EDV) and myocardial fiber stretch regarding preload?
- What is the primary determinant of the afterload faced by the left ventricle under physiologic conditions?
- Which of the following statements about cardiac output (CO) is correct under steady-state physiology?
- If sympathetic stimulation increases heart contractility (inotropy) without changing preload or afterload, what happens to stroke volume an…
- Which event in the cardiac cycle corresponds most closely with the peak of the QRS complex on ECG in the context of mechanical events?
- Which change would you expect in the left ventricular pressure–volume loop if afterload is acutely increased (e.g., acute hypertension)?