Low-level exercise testing before and after coronary artery bypass surgery.
Heart rate and blood pressure responses to low-level exercise tests in patients immediately before and after coronary artery bypass graft surgery lack sufficient documentation. This study documents heart rate, blood pressure, electrocardiographic responses and symptoms during low-level treadmill tests (LLTT) of 19 patients in two subgroups (A and B) before surgery, and again the day before hospital discharge. Preoperatively, the most common reason for stopping the treadmill test early was onset of angina. Postoperatively, patients stopped due to fatigue (4), dyspnea (6), and dizziness (2). Mean resting heart rate responses increased 37% in group A (n = 9) and 40% in group B (n = 10) from the preoperative to postoperative test. Mean postoperative resting pressure rate product responses increased 16% in group A and 38% in group B compared to preoperative values. Mean resting systolic blood pressure responses were 15% lower postoperatively for group A. This LLTT proved to be a clinically feasible tool which provided objective information about the patient's readiness for discharge and exercise prescription.