When is Coronary Blood Flow Greatest

Question

When is coronary blood flow greatest?
A) During ventricular contraction
B) Immediately following the QRS complex on the ECG
C) During ventricular diastole
D) During ventricular systole

Accepted Answer

Coronary blood flow is greatest during ventricular diastole, when the coronary arteries are able to fill with blood due to relaxation of the myocardium. During systole, the myocardium contracts and compresses the intramural arteries, decreasing blood flow.