A patient recovering from surgery for triple coronary artery bypass grafts is scheduled to begin a phase III cardiac rehabilitation program. During the resistance portion of the circuit training program, whys should the patient be instructed to AVOID the Valsalva maneuver?

A. To avoid elevating the heart rate and blood pressure

B. To avoid accumulation of peripheral fluid and resulting edema

C. Because it may produce slowing of pulse and increased venous pressure

D. Because a cholinergic or vagal response may occur