Cardiac rehabilitation following coronary artery bypass surgery

Workload of an inpatient cardiac rehabilitation service in Edinburgh: a five year survey

When the cardiac rehabilitation programme at Astley Ainslie Hospital, Edinburgh, UK, was instituted in 1976, it served predominantly patients under 65 years of age who had suffered a recent myocardial infarction. We describe a detailed survey of the medical records of all cardiac admissions to the Rehabilitation Medicine Unit of the hospital during 1986-1990. This survey stresses the changing face of cardiac rehabilitation which has now developed fundamentally into a post cardiac surgical rehabilitation service, catering to an increasingly elderly group of patients. Perhaps this is a logical development as cardiologists and general physicians become more aware of the rehabilitation needs of patients post myocardial infarction and these are instituted both in the acute setting and as an outpatient service. In contrast, cardiothoracic surgical units with the need for high technology and specialist intensive care skills are perhaps environments less suited to the institution of rehabilitation services.

The consequences and opportunities of shortened lengths of stay for cardiovascular patients

Length of hospitalization for many cardiovascular conditions has decreased dramatically recently. Many attribute this increase to the cost constraints imposed by managed care and to improved technologies. Although technological developments have contributed to cost inflation, they have also reduced the need for long hospitalizations and improved patient outcomes. This new context for delivering cardiovascular services is discussed in terms of the challenges and opportunities for nursing leadership in several aspects of care.

Central and peripheral adaptations after 12 weeks of exercise training in post-coronary artery bypass surgery patients

PURPOSE

Training adaptations in patients with coronary artery disease (CAD) have been reported previously, but little is known about central and peripheral adaptations in those recovering from coronary artery bypass graft surgery (CABG). The purpose of this study was to examine the effects of 12 weeks of endurance exercise training on exercise performance and left ventricular and peripheral vascular reserve in a group of uncomplicated CABG patients.

METHODS

Thirty-one patients were recruited and began training 8 to 10 weeks after uncomplicated CABG. Patients underwent progressive exercise training consisting of walking and jogging, at 75% to 80% maximal oxygen intake (VO2max). Measures of left ventricular function included ejection fraction (EF), ventricular volumes, and the pressure volume ratio, an index of contractility. Peak ischemic exercise calf blood flow and vascular conductance was determined using strain-gauge plethysmography. Maximal oxygen intake and submaximal blood lactate concentration also was determined.

RESULTS

A significant improvement in VO2max (1497 +/- 60 mL/min versus 1691 +/- 71 mL/min) was observed after training. This change was accompanied by an increase in the EF during submaximal exercise (60 +/- 3% versus 63 +/- 2% at 40% VO2max; 61 +/- 3% versus 64 +/- 3% at 70% VO2max) (P < 0.05), and the change in EF from rest to exercise (delta EF). No changes were observed for ventricular volumes during exercise, although there was a trend for a higher stroke volume at 70% VO2max. A significant increase (18%) was observed for peak ischemic exercise calf blood flow and vascular conductance. In addition, submaximal blood lactate concentration was lower after training.

CONCLUSIONS

These data indicate that exercise training for 12 weeks in patients recovering from CABG can elicit significant improvements in functional capacity that, for the most part, are secondary to peripheral adaptations, with limited support for improvement in left ventricular function.

The psychology of men and women recovering from coronary artery bypass surgery

BACKGROUND

Little is known about the differences between men's and women's cardiac rehabilitation processes. What helps men during recovery may not necessarily aid women's recovery. Psychosocial variables are known to impact recovery in positive and negative ways. Unfortunately, it is not clear what variables are the most effective predictors of recovery outcomes for men and women.

METHODS

Ninety coronary artery bypass graft patients (60 men, 30 women) completed a battery of psychological questionnaires on or after the third day after surgery.

RESULTS

Results showed that women reported significantly more depressive symptoms than men. For women, pain was correlated positively with depressive symptomatology and functional impairment. For men, pain and functional impairment were correlated negatively with social support. In addition, the results of a multiple regression of pain on age, severity of disease, and two psychosocial variables (depressive symptomatology and social support) for the women showed that after controlling for age and severity of disease, depressive symptomatology and social support accounted for a significant 43% increment in the variance in pain. The psychosocial variables accounted for much less variance in pain in men. However, in a multiple regression of functional impairment on the same variables, depressive symptomatology and social support accounted for a significant 14% increment in the variance in pain in men but a nonsignificant increment for the women.

CONCLUSIONS

The results support the notion that psychosocial variables play different roles in the recovery paths of men and women. In consequence, cardiac rehabilitation programs would be more effective with gender-specific tailoring.

Issues in contemporary cardiac rehabilitation: a historical perspective

Cardiac rehabilitation consists of exercise, psychosocial support and education and is prescribed most often for patients with coronary heart disease. Its purpose is to facilitate readaptation to normal life through the achievement of maximal functional capability and to reduce heart disease risk factors. It began historically with progressive ambulation after myocardial infarction and by 1980 became a standardized inpatient therapy performed according to a stepped procedure. Predischarge exercise testing was added and has become a meaningful contribution to the concept of risk stratification after an acute coronary event. Rehabilitation has subsequently become part of the outpatient environment and is delivered by multiple models. Meta-analyses have shown that rehabilitation reduces overall and cardiovascular deaths by about 20% and sudden death by about 37% during the year after an acute myocardial infarction. The significance of this, however, must now be modulated by the dynamic role of aggressive coronary intervention. Selection for such intervention has become an important adjunctive aspect of rehabilitation. Newer findings suggest that those stratified at low risk will benefit most by the modification of coronary risk factors, and that patients previously thought to be poor candidates for rehabilitation (such as those with significant left ventricular dysfunction and low work capacity) may experience substantial relative functional benefit. Beyond risk stratification, important contemporary issues include surveillance of patients after angioplasty, the effectiveness of rehabilitation in the attenuation or reversal of both native and vein graft atherosclerosis and consideration of such currently emphasized end points as quality of life and economic evaluation.

Emotional support as a moderator of adjustment and compliance after coronary artery bypass surgery: a longitudinal study

The independent relationships of emotional support and marital status with posthospital adjustments following coronary artery bypass surgery (CABS) were examined longitudinally with an intake sample of 85 male patients. Follow-ups occurred at 1, 4, and 13 months after hospital release. Demographic characteristics (age, education) and cardiac status at the time of surgery (wall motion abnormalities) were controlled statistically. As anticipated, married patients were higher in emotional support throughout the follow-up period than were their unmarried counterparts, and both groups reported decreased support with time. Of more interest, higher support was significantly and independently predictive of better emotional status (lower anxiety, depression), perceived quality of life, and compliance with recommended behaviors (ambulating and not smoking). Support did not predict cardiac health (angina episodes, doctor visits for cardiac problems) during follow-up, however. There was no evidence that marital status, independent of emotional support, was related significantly to outcomes.

Effects of daily high-intensity exercise on myocardial perfusion in angina pectoris

Forty male patients with chronic stable angina pectoris and no prior myocardial infarction were studied by planar thallium scintigraphy with use of circumferential profile analysis. Ischemic defects were assessed by measuring degrees of circumference involved and area of defect. Data were collected for 3 vascular regions in each of 3 views (anterior, 45 degrees and 65 degrees left anterior oblique projection). Patients were then randomized to exercise and control groups, the former training for a period of 1 year using the Canadian Airforce plan for physical fitness. After 1 year, both groups were restudied. Exercise training produced a 34% reduction in degrees of ischemia overall (p less than 0.02), the most significant change being seen on the anterior view (72 degrees +/- 59 degrees before vs 30 degrees +/- 35 degrees after training). Regional analysis showed markedly improved perfusion anterolaterally and apically on the anterior view and anteroseptally on the 65 degrees left anterior oblique view. These improvements support the hypothesis that exercise training improves myocardial perfusion by enhanced collateral function.

Antianginal efficacy of exercise training: a comparison with beta blockade

Forty men with chronic stable angina and no prior myocardial infarction were studied. Exercise tolerance testing was carried out off treatment and after beta blockade. beta Blockers were stopped and the patients were randomised to a control group and a study group of patients who undertook a one year high intensity training programme. The groups were then restudied. Submaximum heart rate was reduced by 13 beats per minute by training and by 23 beats per minute by atenolol. Training increased the maximum heart rate by 10 beats per minute and atenolol reduced it by 29 beats per minute. The double produce ST threshold was increased from 183 to 205 by training but reduced to 143 by atenolol. Maximum ST depression was similarly reduced by both training and atenolol. As a result of the effects on maximum heart rate, training produced a greater improvement in exercise tolerance than atenolol with a treadmill time increased from 741 seconds to 1272 seconds with training compared with 974 seconds with atenolol. Other variables were similarly affected. Thus the antianginal efficacy of exercise training is as good as that achieved by beta blockade and represents an alternative to such treatment.

Effects of cardiac rehabilitation after coronary artery bypass grafting on readmissions, return to work, and physical fitness. A case-control study

In a case-control study 49 consecutive post-coronary artery bypass grafting (CABG) patients (10 f, 39 m) participating in a comprehensive rehabilitation programme were compared with 98 individually matched double control patients, receiving standard care. The rehabilitation programme, starting 6 weeks after surgery, consisted of follow-up at a coronary clinic, repeated health education, and physical training in out-patient groups. During the first year after CABG, fewer study group patients were readmitted to hospital (14% vs 32%, p less than 0.01) and on fewer occasions (1.1 vs 2.9, p less than 0.05). Fewer patients used anxiolytic drugs (0% vs 15%, p less than 0.01). At the one year post-CABG exercise test we found in the study group a tendency to a greater increase in work capacity, as compared with the values obtained at the preoperative exercise test (33 vs 25 W ns). There were no differences in the rates of returning to work (59% vs 64%). In a long-term follow-up study (av. 38 months post-CABG) the patients were asked to fill in a questionnaire evaluating perceived physical work capacity and training habits. The study group patients rated their physical work capacity higher, and more patients had continued with regular physical training (66% vs 46%, p = 0.05). There were fewer patients using anxiolytic drugs (9% vs 30%, p less than 0.01). Although the programme did not influence the return to work we conclude that it improved the quality of life of our patients as it entailed fewer readmissions and reduced the use of anxiolytic medication; in addition it promoted physical fitness and training habits.

Comparison of supervised and unsupervised exercise training after coronary bypass surgery

Functional capacity and cardiovascular responses to serial graded treadmill testing ( GXT ) were compared in 180 patients who performed prescribed unsupervised exercise and 24 patients who were referred for supervised exercise after coronary artery bypass surgery (CABS). The groups were men similar in age range, number of bypass grafts, preoperative left ventricular impairment and number of days hospitalized. All patients received similar predischarge exercise monitoring and began a progressive home walking or cycling program. Initial GXT (T1) was performed 44 +/- 9 days postoperatively. Both groups were instructed to continue prescribed exercise at 75 to 85% maximal heart rate (HR) for 30 to 40 minutes 3 days (supervised) or 5 days ( unsupervised ) per week. The second GXT (T2) was performed 115 +/- 27 days after CABS. In each group there were significant (p less than 0.01) increases in exercise capacity and HR from T1 to T2. However, there were no significant differences in maximal exercise capacity and HR between groups at T1 or T2. Improvement in functional capacity was not influenced by therapeutic beta blockade. These findings indicate that prescribed unsupervised exercise can be performed safely and results in similar functional improvements compared with supervised exercise after uncomplicated CABS.