Demonstration of training effect during chronic beta-adrenergic blockade in patients with coronary artery disease.

Abstract

SUMMARY Attenuation of exercise-induced increases in heart rate and cardiac output by chronic f3-adrenergic blockade has been thought to conmpromise benefit of exercise training in patients with coronary artery disease (CAD). To assess this important issue, 35 CAD patients were evaluated by a 3-month walkjogcycle training program: 14 patients received no blocker (group 1), 14 received propranolol,' 30-80 mg/day (group 2), and seven patients'received propFan'olol, 120-240 mg/day (group 3). The extent of CAD, resting heart rate before training blood pressure and V02 max were similar (p = NS) in each group. The maximal exercise heart rate (mean i SD, 147 ± 21 beats/min in group 1 vs 120 ± 10 beats/min in group 2 and 115 12 beats/min in group 3 (both p < 0.05 vs group 1). The V02 max before training was 25 5.0 mI/kg/mm in group 1 vs 23 3.2 ml/kg/min in group 2 and 26 ± 2.8 ml/kg/min in group 3 (allp = NS). Training consisted of three 1-hour periods per week at a heart rate of 70-85% of the maximal pretraining heart rate. In each group, VO2 increased (p < 0.05) after training: group 1, 27%; group 2, 30%; group 3, 46%. The'double product was unchanged after training (p = NS) in each group.These Despite the widespread clinical usage of 3-adrenergic blocking drugs in coronary artery disease and the common practice of prescribing exercise conditioning programs to patients with ischemic heart disease, many of whom are receiving d-blocking agents, objective data concerning the effect of these drugs on the patient's ability to achieve a training effect are lacking. It has been presumed that chronic exercise during therapeutically imposed limitation in heart rate

Does exercise alter anaerobic threshold in coronary artery disease during beta blockade?

“…On the other hand, Obma et al, 1979;Pratt et al, 1981;Vanhees et al, 1982 andGordon et al, 1983 found significant increase in V02 max after training in coronary artery disease during long term beta adrenergic blockade. Our findings (Table 11 and Fig.…”

“…Hossack et al, 1981, in their studies on propanolol on exercise training "prescription" demonstrated a minor but insignificant change in the ratio of maximal oxygen uptake to maximum heart rate. Contrary to Hossack et al, 1981;Obma et al, 1979;Thadani and Parker, 1979;Pratt et al, 1981;Vanhees et al, 1982;and recently Gordon et al, 1983, showed an improved cardiovascular and ventilatory responses after training in patients with coronary heart disease during beta-adrenergic blockade. Table I represents the mean values with the standard deviation of physical characteristics and responses to maximal treadmill test before and after training in patients with coronary artery disease (CAD).S The data demonstrate a significant increase in V02 max, m4ximum 02 pulse, absolute treadmill time (duration) and reduction in maximum heart rate before and after training of 12-16 weeks.…”

Changes in Systolic Time Intervals during Physical Training in Patients with Ischemic Heart Disease

“…4], However, mod erate doses in normal subjects [9] or chronic treatment with p-blocking agents in patients with ischemic heart disease [5][6][7][8] did not alter the effects of training. Also in the present investigation similar increases in ex ercise capacity were found in patients with and in patients without p-blocking drugs.…”

“…An increasing number of these patients are treated with P-blocking agents because of angina pectoris, hypertension or for secondary prevention [1], It has been sug gested that the negative chronotropic and inotropic actions of p-adrenoceptor blockade could alter the effects of training [2][3][4], In recent studies, however, it has been demon strated that chronic treatment with p-adrenergic blocking agents does not necessarily im pair training effects such as the increase in exercise capacity, the training induced lower ing of heart rate and the hemodynamic ef fects of training [5][6][7][8][9], Because of their noninvasive nature, re peated measurements of systolic time inter vals (STI) are suited for longitudinal observa tions on cardiac function [ 10] in the course of a training programme.…”

Exercise and lifestyle predictors of resting heart rate in healthy young adults

“…These physiological responses to regular exercise increase cardiac peak function, permitting higher levels of physical work [5,6,[11][12][13]. Exercise-induced cardiac adaptations also promote cardiac health under nonexercise conditions, as regular exercise reduces resting heart rate (examples in [14][15][16][17]) and resting blood pressure as well [18][19][20].…”