Effects of exercise on plasma renin, aldosterone and catecholamines before and after surgery for aortic coarctation.

The pre- and postoperative values of blood pressure, pulse rate, plasma renin activity, plasma aldosterone concentration and circulating catecholamines were studied in a group of 12 patients with uncomplicated aortic coarctation before and after exercise. Mean age of patients studied was 21.5 years. Postoperative studies were carried out on average 204 days after surgery. Following operation, both resting and exercising upper extremity pressures decreased. Six out of the 11 patients still had an abnormally high exercising blood pressure when compared with a normal control group of six persons. Postoperative pulse rates during exercise were significantly higher than pre-operatively (P less than 0.01). No statistically significant differences between pre- and postoperative values, and between patients and normal controls were found in the hormonal studies. This study suggests that the renin-aldosterone-system does not have a major role in the maintenance of the hypertension associated with coarctation of the aorta.