Lifestyle modification program in management of patients with coronary artery disease: the clinical experience in a tertiary care hospital.

OBJECTIVES: The authors examined clinical outcomes in 71 male and female patients with coronary atherosclerosis who enrolled in a 2-year, independent-living, lifestyle modification program. The findings in 43 patients who completed the program were compared with those in 28 patients who dropped out of the program. BACKGROUND: Clinical studies suggest that lifestyle modification of risk factors for coronary atherosclerosis reduces subsequent cardiac events but there are very few reports of the effect of these programs in patients living independently. METHODS: Patients with diagnosed coronary atherosclerosis were managed for a 2-year period in a structured multidisciplinary program by a team that included two cardiologists, a nurse, a dietitian, an exercise physiologist, and a clinical psychologist. The overall aim of the program was to normalize or control all major reversible cardiovascular risk factors. Patients were required to participate in several weekly sessions for exercise, meditation/stress reduction training, dietary education and counseling, and participatory dinners. There was a strong emphasis on patient's self care, inclusion of support members, and regular monitoring of and feedback to patients. RESULTS: Data comparing baseline and 2-year outcomes showed a significant reduction in body weight, dietary intake of total/saturated fat and cholesterol, serum low- and high-density lipoprotein concentration, and an increase in exercise capacity. In the compliant group, the incidence of cardiac events was 2.3% over 2 years. CONCLUSION: Multidisciplinary lifestyle modification programs addressing cardiovascular risk factors are known to have a significant impact upon cardiac risk factors in patients with coronary atherosclerosis. Data show that these changes can be accomplished in independent-living patients in a program offered through a routine cardiology service. However, compliance is an important issue in these self-regulated programs.

Aerobic exercise training reduces resting and exertional blood pressure in cardiac patients.

We evaluated the effects of exercise training (ET) on resting and exertional blood pressure in patients with cardiac disease. ET consisted of 20 to 30 minutes of aerobic activity three times weekly for 12 months. The study group comprised 17 males and three females (mean age 58 years, range 40 to 71 years). Blood pressure was evaluated at rest and during exercise after 6 and 12 months ET. A training effect was documented by an increase in functional capacity from 7.5 METs (1 MET = 3.5 mL oxygen consumption/kg/min) pre-ET to 8.8 and 9.2 METs after 6 and 12 months, respectively. The following significant (P less than 0.05) effects occurred on blood pressure in association with ET: resting systolic pressure pre-ET decreased from 131 to 124 mm Hg at 12 months ET; submaximal (50% pre-ET maximum capacity) systolic and diastolic pressures decreased from 150/84 to 142/80 mm Hg (6 months ET) and 144/80 mm Hg (12 months ET); diastolic pressure at maximal exertion fell from 83 to 77 mm Hg (6 months ET) and 78 mm Hg (12 months ET). Systolic blood pressure at maximal exertion was not increased despite significant increases in peak workload achieved at 6 and 12 months ET. Therefore, ET not only enhances functional capacity in cardiac patients but may be associated with a beneficial cardiac effect through attenuation of both rest and exertional blood pressure.

Exercise training in coronary artery disease.

Physical training using dynamic, nonisometric exercise can increase physical endurance and decrease cardiac work load of submaximal exertion. This is true for people with coronary artery disease and for normal individuals, and it may also be true for those with selected other cardiac diseases. Effective training should involve exercise at between 70 and 85 per cent of predicted maximal heart rate for 15 to 20 minutes or more at least three times a week. An exercise prescription should be written on the basis of individual patient needs and limitations and utilizing an exercise electrocardiogram test. Medically supervised exercise programs allow physical training for patients with heart disease to be conducted safely and efficiently. The effect of training in coronary disease patients is primarily attributable to increased efficiency of peripheral musculature and circulation; how much true cardiac adaptation results is variable. Training improves psychologic outlook, probably reduces selected risk factors for coronary disease, and may improve longevity.

Increase in myocardial oxygen consumption indexes by exercise training at onset of ischemia in patients with coronary artery disease.

It has been unclear whether exercise training of patients with coronary artery disease increases the level of myocardial oxygen consumption, as indicated by heart rate and double product of heart rate and systolic blood pressure, at which electrocardiographic evidence of myocardial ischemia develops. To assess this question we evaluated the experience of 10 patients with coronary artery disease who underwent a modest-level exercise training program for 6 months. All of these subjects had achieved a training effect, had developed electrocardiographic evidence of ischemia during initial exercise testing, had not increased the amount of cardiac medication taken, and had not been taking digoxin. After completion of the training period, the mean heart rate at which electrocardiographic evidence of ischemia developed increased from 107 +/- 19 to 119 +/- 23 beats/min (p less than .05) and the mean double product increased from 166 +/- 18 to 209 +/- 51 X 10(2) mm Hg X beats/min (p less than .05). Eight of the 10 patients demonstrated an increase in heart rate at onset of ischemia (p less than .02), and seven of the eight in whom double product could be assessed manifested an increase in this parameter at onset of ischemia (p less than .05). Thus the rate of myocardial oxygen consumption at which myocardial ischemia develops, as indirectly assessed by heart rate and double product, can be favorably altered by 6 months of moderate-level exercise training.

Efficacy of exercise training in patients with coronary artery disease who are taking propranolol.

The effects of beta-adrenergic blockade on the efficacy of exercise training in patients with coronary artery disease were assessed in a community-based cardiac rehabilitation program. Twenty-five patients took no beta-adrenergic-blocking agent and 17 patients took a constant dose of propranolol during the 3 month study period. Individual exercise prescriptions consisted of an intensity of 70% of maximal workload monitored by heart rate, performed 20 min each session, three sessions per week. Both groups improved in maximal exercise capacity: from 8.7 +/- 1.9 (mean +/- SD) to 9.7 +/- 2.1 mets (p less than .01) in those not taking propranolol and from 6.6 +/- 1.5 to 7.7 +/- 1.8 mets (p less than .01) in those taking the drug. At a workload of 70% of maximal achieved at pretraining testing, heart rate decreased with training from 123 +/- 19 to 113 +/- 17 beats/min (p less than .01) in those not taking propranolol and from 97 +/- 14 to 92 +/- 12 beats/min (p less than .05) in those taking the drug. At a workload of 85% of pretraining maximum, heart rate similarly was lowered with training from 138 +/- 17 to 126 +/- 17 beats/min (p less than .01) in those not taking a beta-blocker and from 107 +/- 13 to 102 +/- 13 beats/min (p less than .02) in those taking propranolol. Thus patients with coronary disease who take propranolol have the same potential to benefit from physical training as patients who do not take beta-blockers, and exercise does not need to be modified because of the drug.

Ventricular ectopy frequency and complexity not altered by exercise training in coronary disease patients.

To assess the effect of exercise training on ventricular ectopy in coronary artery disease patients, 21 patients with coronary disease had 24-hour ambulatory electrocardiograph recordings done at entry into a cardiac rehabilitation program and after 6 months' exercise training. Mean frequency of premature ventricular contractions was not significantly changed, being 9.7 +/- 33.0/h before and 13.2 +/- 94.3/h after training. 9 demonstrated an increased, 9 a decreased, and 3 an unchanged frequency. Lown grade of ventricular ectopy was similarly not consistently changed with training.

Antianginal efficacy and improved exercise performance with timolol. Twice-daily beta blockade in ischemic heart disease.

Antianginal efficacy and improved exercise performance with timolol, a new beta-adrenergic blocking agent, was assessed in 23 patients with chronic stable angina pectoris in an 11-week double-blind, placebo-controlled study. Twenty-two of the 23 subjects completed the open-label phase of this investigation (weeks 0 to 6) while receiving 10 to 30 mg of timolol twice daily to optimize exercise capacity. Weekly anginal episodes and nitroglycerin consumption declined from 8.9 +/- 9.1 episodes/week and 8.1 +/- 10.6 tablets/week, respectively, with placebo to 2.7 +/- 5.2 episodes/week and 2.6 +/- 6.0 tablets/week with optimal timolol dose (p less than 0.05). Resting heart rate (HR) and systolic blood pressure (SBP) also decreased from 75.2 +/- 14.0 beats/min and 139.1 +/- 15.7 mm Hg with placebo to 55.1 +/- 8.9 beats/min and 130.5 +/- 15.9 mm Hg with timolol (p less than 0.05). Peak exercise HR, peak exercise SBP, and peak exercise double product (HR X SBP) were significantly (p less than 0.05) reduced when evaluated 12 to 13 hours after administration of timolol compared with placebo (101.5 +/- 21.1 beats/min verus 193.3 +/- 96.2 beats/min, 161.5 +/- 26.7 mm Hg versus 175.6 + 20.8 mm Hg, and 16.6 +/- 5.1 X 10(-3) versus 21.7 +/- 5.4 X 10(-3), respectively). Exercise duration was prolonged from 263.3 +/- 90.2 seconds to 330.3 +/- 73.9 seconds (p less than 0.05), while time to onset of 1 mm S-T segment depression was delayed in 15 patients from 231.8 +/- 86.4 seconds to 298.7 +/- 68.4 seconds (p less than 0.05). During the double-blind phase (weeks 7 to 10), 8 subjects received timolol and 11 patients received placebo. Nitroglycerin consumption at weeks 8 and 10 and anginal frequency at week 8 were unchanged compared with initial placebo treatment. Resting HR, peak exercise HR, and peak exercise double product were significantly attenuated at weeks 8 and 10 in timolol patients compared with their initial placebo exposure. However, these variables were unchanged in placebo subjects compared with their initial placebo therapy. Exercise duration was again prolonged at week 8 in timolol subjects compared with initial placebo results (315.1 +/- 61.2 seconds versus 261.3 +/- 68.8 seconds, p less than 0.05), but not at week 10. Placebo patients demonstrated no difference at week 8 or 10 in exercise performance compared with initial placebo treatment. Timolol twice daily, therefore, is potentially useful in some patients with angina pectoris. Other patients may, however, require a shorter dose interval for optimal angina control and maximal improvement in exercise capacity.