A 40-year-old man is being evaluated in the office for routine health follow up. He states that he feels chest discomfort which started 2 days ago. He is well and active , he also has a family history of an ischemic heart disease. The patient has no medical conditions and does not use tobacco. He leads an active lifestyle and exercises every day. He undergoes treadmill exercise stress testing. Baseline blood pressure is 120/73 mm Hg and pulse is 59/min. After 10 minutes of exercise, his blood pressure is 156/82 mm Hg and pulse is 153/min. He has no chest pain and ECG shows no abnormalities. Compared to pretest conditions, which of the following is the single most important limiting factor for left ventricular myocardial blood supply during the test?

Question

A 40-year-old man is being evaluated in the office for routine health follow up. He states that he feels chest discomfort which started 2 days ago. He is well and active , he also has a family history of an ischemic heart disease. The patient has no medical conditions and does not use tobacco.  He leads an active lifestyle and exercises every day.  He undergoes treadmill exercise stress testing.  Baseline blood pressure is 120/73 mm Hg and pulse is 59/min.  After 10 minutes of exercise, his blood pressure is 156/82 mm Hg and pulse is 153/min.  He has no chest pain and ECG shows no abnormalities.  Compared to pretest conditions, which of the following is the single most important limiting factor for left ventricular myocardial blood supply during the test?

Quizplus · Accepted Answer

Eductional Objective: During systolic ventricular contraction, as increase in systolic interventricular pressure and wall stress will result in decrease myocytes blood supply. so the majority of left ventricular myocardial perfusion occurs during diastole. During exercise there is a short diastolic duration that leads to limit coronary blood supply.

A 40-Year-Old Man Is Being Evaluated in the Office for Routine