title: Changes in cardiac functional capacity after coronary bypass surgery in relation to adequacy of revascularization.
abstract: Seventy patients having aortocoronary vein bypass grafting surgery for angina pectoris underwent preoperative invasive exercise testing to symptom limits and again 6 to 14 months postoperatively. Cardiac output was measured using the direct Fick principle. Postoperatively at maximal exercise, there was a 3.11 liters/min (p less than 0.0001) increase in cardiac output in men (n = 61) and a 2.04 liters/min (p less than 0.01) increase in women (n = 9). Patients with complete revascularization showed a significantly greater improvement in cardiac output postoperatively than did those with incomplete revascularization (26 versus 6%, p less than 0.0001). The major reason for the increased maximal cardiac output was a marked increase in heart rate while stroke volume was maintained at the same preoperative level. These findings were true irrespective of preoperative use of beta-adrenergic blocking drugs.
mesh_terms: D000319:Adrenergic beta-Antagonists / Q000008:administration & dosage; D000368:Aged; D000787:Angina Pectoris / Q000601:surgery; D002302:Cardiac Output; D001026:Coronary Artery Bypass; D005080:Exercise Test; D005260:Female; D005500:Follow-Up Studies; D006321:Heart / Q000502:physiology*; D006339:Heart Rate; D006801:Humans; D008297:Male; D008875:Middle Aged; D010100:Oxygen / Q000097:blood; D010101:Oxygen Consumption; D013318:Stroke Volume
chemical_list: D000319:Adrenergic beta-Antagonists; D010100:Oxygen