You are in: eMedicine Specialties > Physical Medicine and Rehabilitation > REHABILITATION PROTOCOLS Cardiac RehabilitationArticle Last Updated: Mar 28, 2006AUTHOR AND EDITOR INFORMATION
Author: Vibhuti N Singh, MD, MPH, FACC, FSCAI, Director, Suncoast Cardiovascular Center; Chair, Cardiology Division and Cath Labs, Department of Medicine at Bayfront Medical Center; Clinical Assistant Professor, Division of Cardiology, University of South Florida College of Medicine Vibhuti N Singh is a member of the following medical societies: American College of Cardiology, American College of Physicians, American Heart Association, American Medical Association, and Florida Medical Association Coauthor(s): Douglas D Schocken, MD, FACC, FACP, Courtesy Professor, Department of Gerontology, University of South Florida College of Arts and Sciences; Professor, Departments of Medicine and Epidemiology and Biostatistics, University of South Florida College of Medicine; Karen Williams, MD, Medical Director, Bayfront Rehabilitation Services, Bayfront Medical Center; Robert Stamey, Jr, BS, Manager, Department of Cardiopulmonary Rehabilitation, Bayfront Medical Center Editors: Robert J Kaplan, MD, Associate Professor, Department of Physical Medicine and Rehabilitation, University of Kansas School of Medicine and Medical Center; Francisco Talavera, PharmD, PhD, Senior Pharmacy Editor, eMedicine; Richard Salcido, MD, Chairman, Erdman Professor of Rehabilitation, Department of Physical Medicine and Rehabilitation, University of Pennsylvania School of Medicine; Kelly L Allen, MD, Consulting Staff, Department of Physical Medicine and Rehabilitation, Lourdes Regional Rehabilitation Center, Our Lady of Lourdes Medical Center; Consuelo T Lorenzo, MD, Consulting Staff, Department of Physical Medicine and Rehabilitation, Alegent Health Care, Immanuel Rehabilitation Center Author and Editor Disclosure Synonyms and related keywords: rehabilitation in patients with heart disease, exercise and heart disease, rehabilitation after heart attack, rehabilitation after bypass surgery INTRODUCTION
BackgroundCardiovascular disorders are the leading cause of mortality and morbidity in the industrialized world, accounting for almost 50% of all deaths annually. The survivors constitute an additional reservoir of cardiovascular disease morbidity. In the United States alone, over 14 million persons suffer from some form of coronary artery disease (CAD) or its complications including congestive heart failure (CHF), angina, and arrhythmias. Of this number, approximately 1 million survivors of acute myocardial infarction (MI), and 309,000 patients who have undergone coronary bypass surgery annually, are candidates for cardiac rehabilitation. Traditionally, cardiac rehabilitation has been provided to somewhat lower-risk patients who could exercise without getting into trouble. However, astonishingly rapid evolution in the management of CAD has now changed the demographics of the patients who can be candidates for rehabilitative training. Currently, about 400,000 patients who undergo coronary angioplasty each year comprise a subgroup that could benefit from cardiac rehabilitation. Furthermore, approximately 4.7 million patients with CHF are also eligible for a slightly modified program of rehabilitation, as are the ever-increasing number of patients receiving heart transplantation. This review addresses the objectives, indications, program components, exercise training, monitoring, benefits, risks, safety issues, outcome measures, and cost effectiveness of cardiac rehabilitation. ObjectivesCardiac rehabilitation aims to reverse the limitations that have developed following adverse pathophysiologic and psychological consequences of cardiac events. Identification of the patients at risk for recurrence of such events (ie, risk stratification) is central to formulating an appropriate medical, rehabilitative, and surgical strategy to prevent such recurrences. Patients who are at low or moderate risk typically undergo early rehabilitation. The major goals of cardiac rehabilitative programs are:
Cardiac rehabilitation programs have been consistently shown to improve objective measures of exercise tolerance and psychosocial well being, without increasing the risk of significant complications. UtilizationThe Agency for Health Care Policy and Research (AHCPR); National Heart, Lung and Blood Institute (NHLBI); and the American Association of Cardiovascular and Pulmonary Rehabilitation (AACVPR) have recognized the wide variation in awareness and understanding of the role of cardiac rehabilitation among physicians, ancillary health care providers, third-party payers, and patients with heart disease. Only 11% of patients participate in rehabilitation programs following acute coronary events. In the past few years, fortunately, the participation in these programs has increased. Approximately 38% of US patients and 32% of Canadian patients with acute MI who were involved in the Global Utilization of Streptokinase and t-PA for Occluded Coronary Arteries (GUSTO) trial were enrolled in cardiac rehabilitation programs. Outcome measuresCurrent cardiac care has already reduced early acute coronary mortality so much so that further exercise training, as an "isolated" intervention, may not be able to cause significant reduction in the morbidity and mortality. Nonetheless, exercise training has the potential to act as a catalyst for promoting other aspects of rehabilitation, including risk factor modification through therapeutic lifestyle changes (TLC) and optimization of psychosocial support. Therefore, the outcome measures of cardiac rehabilitation now include improvement in quality of life (QOL), such as the patient's perception of physical improvement, satisfaction with risk factor alteration, psychosocial adjustments in interpersonal roles, and potential for advancement at work commensurate with the patient's skills (rather than simply return to work). Similarly, among patients who are elderly, such outcome measures may include achievement of functional independence, prevention of premature disability, and reduction in the need for custodial care. Despite limited data, older patients of both sexes in observational studies have been shown to improve their exercise tolerance comparable to younger patients participating in equivalent exercise programs. In addition, the safety of exercise within cardiac rehabilitation programs, as studied in over 4,500 patients, is well accepted and established. Cardiac rehabilitation services are, therefore, an effective and safe intervention. These services are, undoubtedly, an essential component of the contemporary treatment of patients with multiple presentations of coronary heart disease and heart failure. HISTORY AND DEFINITION OF CARDIAC REHABILITATION
HistoryIn the 1930s, patients with MI were advised to observe 6 weeks of bedrest. Chair therapy was introduced in the 1940s. By the early 1950s, 3-5 minutes of daily walking was advocated, beginning at 4 weeks. Clinicians gradually began to recognize that early ambulation avoided many of the complications of bedrest, including pulmonary embolism (PE), and it did not increase the risk. However, concerns about safety of unsupervised exercise remained strong, which led to the development of structured physician-supervised rehabilitation programs that included clinical supervision, as well as electrocardiographic monitoring. In the 1950s, Hellerstein set out his thoughts for the comprehensive rehabilitation of patients recovering from acute cardiac events. He advocated a multi-disciplinary approach to the rehabilitation program. His approach has been adopted by the so-called "cardiac rehabilitation programs" throughout the world. Despite multiple advances, Hellerstein's original ideas have not been improved upon significantly. However, due to changing patient demographics, many more patients now have the opportunity to receive the benefits offered by cardiac rehabilitation. Multifactorial intervention, including aggressive risk factor modification, has become an integral part of present day cardiac rehabilitation. DefinitionAccording to the US Public Health Service (USPHS), cardiac rehabilitation is defined as a rehabilitative program that involves the following:
Cardiac rehabilitation has to be both comprehensive and individualized at the same time. The main goals of a cardiac rehabilitation program should include the following:
Physiology of exercise and cardiovascular benefitCoronary vasodilatation is mainly driven by bioavailability of nitric oxide (NO), which is produced by the activities of endothelial-derived enzyme, NO synthase, and metabolized by reactive oxygen species. This fine-tuned balance is disturbed in person with CAD. This form of impairment of NO production, along with excessive oxidative stress, results in loss of endothelial cells via apoptosis. Further aggravation of endothelial dysfunction, in turn, ensues, which triggers myocardial ischemia in persons with CAD. In healthy individuals, increased release of NO from the vascular endothelium in response to exercise training results from changes in endothelial NO synthase expression, phosphorylation, and conformation. By the same token, exercise training has assumed a role in cardiac rehabilitation of patients with CAD because it reduces mortality and increases myocardial perfusion. This has been largely attributed to exercise training–mediated correction of coronary endothelial dysfunction in persons with CAD. Regular physical activity leads to restoration of the balance between NO production by NO synthase and NO inactivation by reactive oxygen species in persons with CAD, thereby enhancing the vasodilatory capacity in various vascular beds. Because endothelial dysfunction has been identified as a predictor of cardiovascular events, the partial reversal of endothelial dysfunction achieved by regular physical exercise appears to be the most likely mechanism responsible for the exercise training–induced reduction in cardiovascular morbidity and mortality in patients with CAD. PATIENT SELECTION AND RISK STRATIFICATION
Patient selectionCardiac rehabilitation encompasses both short-term and long-term goals that are to be achieved through exercise, education, and counseling. The patients generally fall into following categories:
The short-term goals of cardiac rehabilitation include restoration of the physical, psychological, and social condition, while the long-term goals involve promotion of heart-healthy behaviors that enable the individual to return to productive and/or joyful vocational and avocational activities. The cardiac rehabilitation programs benefit women and men equally. Elderly patients also can derive significant benefit from rehabilitation programs. Risk stratificationThe risk stratification process is very valuable for cardiac patients; it serves as the basis for individualizing prescription of exercise training and assessing the need and extent of supervision required. The risk stratification process is based upon the assessment of the following patient attributes: (A) Functional capacity
Every attempt should be made to recognize the potential effects of these factors on functional capacity in order to minimize risk of the individualized reconditioning program that is being formulated. (B) Myocardial ischemia
(C) Ventricular dysfunction
(D) Arrhythmias
(E) Educational and psychosocial status
Initial continuous ECG monitoring is recommended in most patients during cardiac rehabilitation exercise training; however, clinicians may decide whether to use continuous or intermittent ECG monitoring. After the initial period, use of ECG depends on the clinical judgment of the supervising physician. (F) Alternative approaches to cardiac rehabilitation In carefully selected patients, alternatives to the traditional supervised (group or individual) cardiac rehabilitation program have been examined. These alternatives are applicable primarily to very low-risk patients and include the following options:
Cardiac rehabilitation in patients with heart failureHeart rate recovery (HRR) after maximal exercise is a predictor of all-cause mortality. In a 2006 study, Streuber et al hypothesized that aerobic exercise training could increase HRR in patients with heart failure because it has been shown to be accelerated in athletes and improved in patients with CAD after cardiac rehabilitation. They conducted a retrospective study of 46 patients with heart failure who had completed a phase 2 aerobic cardiac rehabilitation program with entry and exit maximal stress tests. The results indicated that even short-term aerobic training can favorably modify HRR in patients with heart failure who have low exercise capacity. EXERCISE TESTING AND EXERCISE PRESCRIPTION
IndicationsCardiac rehabilitation initially was designed for low-risk cardiac patients. Now that the efficacy and safety of exercise have been documented in patients previously stratified to the high-risk category, such as those with CHF, the indications have been expanded to include such patients. Exercise training benefits persons with the following cardiac conditions:
Exercise prescription depends on the results of exercise testing, which often includes cardiopulmonary exercise (CPX) testing. Modifications of exercisePatients with limitations due to chronic obstructive pulmonary disease (COPD), peripheral vascular disease (PVD), stroke, and orthopedic conditions still can be trained in the exercises through special techniques and adaptive equipment (eg, use of arm-crank ergometer). ContraindicationsCardiac rehabilitation services are contraindicated in patients with the following conditions:
In such patients, every effort should be made to correct these abnormalities through optimization of medical therapy, revascularization by angioplasty or bypass surgery, or electrophysiologic testing and subsequent antiarrhythmic drug or device therapy. Patients should then undergo retesting for exercise prescription. Exercise testingTwo forms of exercise tests are performed in patients following an acute cardiac event: submaximal exercise testing and symptom-limited exercise testing. Furthermore, CPX also may be performed, particularly in patients with cardiomyopathy or CHF, to determine objectively the patient's exercise capacity.
Submaximal exercise testing is not necessarily safer than the symptom-limited testing. In fact, submaximal strategy may have certain disadvantages including (1) failure to elicit important factors in prognosis, such as ischemia, cardiac dysfunction, or arrhythmia, (2) inappropriate limitation in patient's routine activities and exercise training, and (3) significant delay in the patient's returning to work.
Exercise prescription and surveillancePhase 2 of a cardiac rehabilitation program is initiated based on the result of the exercise testing, and the exercise prescription is individualized. Three main components of an exercise training program are as follows:
Exercise initiation Exercise sessions should begin with 10 minutes of warm-up, during which light calisthenics and muscular stretching are performed to avoid muscle injury and bring about a graded increase in heart rate. This warm-up period is followed by 40 minutes of aerobic exercise (eg, walking, jogging, bicycling) and a final 10 minutes of cool-down period involving muscular stretching. The cool-down period is very important. Gradual cool-down prevents ventricular arrhythmias, which may occur in patients with coronary disease on abrupt cessation of exercise. Progression The patient's peak heart rate is noted. The target is, subsequently, increased by 5-10% of the peak heart rate until the patient is able to exercise at 85% of the peak heart rate. Most patients are able to do so by 2-3 months. A follow-up treadmill test should be performed at 4-8 weeks after the patient starts the program, and the result should be used to fine tune the exercise training. Special considerations In patients with myocardial ischemia, exercise training still can be performed safely. The maximal heart rate should be kept 10 beats per minute (bpm) lower than the heart rate at which ischemia occurred. Closer surveillance and ECG monitoring are recommended in patients following myocardial ischemia. Patients with arrhythmias also need ECG monitoring. Patients with CHF require a much more modified exercise program. PHASES OF CARDIAC REHABILITATION
Cardiac rehabilitation services are divided into 3 phases beginning with phase 1 that is initiated while the patient is still in the hospital, followed by phase 2 that is a supervised ambulatory outpatient program spanning 3-6 months, and subsequently continuing into phase 3, a lifetime maintenance phase, in which physical fitness, as well as additional risk factor reduction, are emphasized. Cardiac rehabilitation: Phase 1 (in-hospital phase)
Cardiac rehabilitation: Phase 1.5 (Postdischarge phase)
Cardiac rehabilitation: Phase 2 (supervised exercise)
Cardiac rehabilitation: Phase 3 (maintenance phase)
Sexual activity
OUTCOMES OF CARDIAC REHABILITATION TRAINING
Cardiac rehabilitation provides many benefits for patients. The most important benefits are discussed below. Improved exercise tolerance Cardiac rehabilitation exercise training for patients with coronary heart disease or CHF leads to objectively verifiable improvement in exercise capacity in men and women, regardless of age. Adverse outcomes or complications of exercise are exceedingly rare. The nonfatal infarction rate is 1 patient per 294,000 patient-hours; the cardiac mortality rate is 1 patient per 784,000 patient-hours. The benefits are even greater in patients with diminished exercise tolerance. This beneficial effect does not persist long-term after completion of cardiac rehabilitation without a long-term maintenance program. Therefore, exercise training must be maintained long term to sustain the improvement in exercise capacity. Control of symptoms In patients with coronary heart disease, angina significantly improves during the cardiac rehabilitation exercise program. Objective evidence of improvement in ischemia has been seen by performing interval stress ECG or radionuclide testing. Similarly, patients with LV failure or dysfunction show improvement in the symptoms of heart failure. Use of gas analysis (CPX) has shown that patients' exertional tolerance improves significantly with exercise training. Improvement in the blood levels of lipids Improvements in lipid and lipoprotein levels are observed in patients undergoing cardiac rehabilitation exercise training and education. Exercise must be combined with dietary and medical interventions for required lipid control. Effect on body weight Exercise training as a sole intervention has an inconsistent effect on controlling excess weight. Optimal management of obesity requires multifactorial rehabilitation, including nutritional education and counseling, behavioral modification, and exercise training. Effect on blood pressure Rehabilitative exercise training as a sole intervention has minimal effect; however, multifactorial intervention has been shown to have beneficial effects. Inconsistencies with this theory remain unresolved. Reduction in smoking Cardiac rehabilitation services with well-designed educational, counseling, and behavioral modification programs result in cessation of smoking in a significant number of patients. Cessation of smoking can be expected in 16-26% of patients. This reduction is combined with the spontaneously high smoking cessation rates following acute coronary events. Improved psychosocial well being Cardiac rehabilitation exercise and education services enhance measures of psychological and social functioning. Reduction of stress In multifactorial cardiac rehabilitation programs, improvement in the measures of emotional stress occurs, as well as reduction of Type A behavior patterns. This reduction of stress is consistent with improvement in psychosocial outcomes that occurs in nonrehabilitation settings. Enhanced social adjustment and functioning Cardiac rehabilitation exercise training improves social adjustment and functioning. Exercise training is recommended to improve these social outcomes. Return to work Cardiac rehabilitation exercise training exerts less influence on rates of return to work than on other aspects of life. Many nonexercise variables also affect this outcome (eg, prior employment status, employer attitude, economic incentives). Reduced mortality Scientific data suggest a survival benefit for patients who participate in cardiac rehabilitation exercise training, but it is not attributable to exercise alone. This survival benefit is due to multifactorial interventions. A meta-analysis of the post-MI randomized controlled trials of exercise has shown a 25% reduction in mortality at 3-year follow-up. This magnitude of benefit is as large as the benefit seen with the use of beta-blockers post-MI or with the use of ACE inhibitors in LV dysfunction along with MI. Trials that involve exercise alone still show a 15% mortality reduction. Pathophysiologic measures Extent of coronary atherosclerosis: When combined with intensive dietary intervention, with and without lipid-lowering drugs, exercise training may result in limitation of progression or regression of angiographically documented coronary atherosclerosis. Hemodynamic measurements: Exercise training in patients with heart failure and compromised LV ejection fraction produces favorable hemodynamic changes in the skeletal musculature. Cardiac rehabilitation exercise training is recommended to improve skeletal muscle functioning, but it does not seem to improve hemodynamic function or collateral circulation significantly. Patients following cardiac transplantation Rehabilitative exercise training in patients following orthotropic cardiac transplantation is recommended to improve measures of exercise tolerance. Elderly patients and women Coronary patients who are elderly have exercise trainability comparable to that of younger patients participating in similar rehabilitative programs. Elderly patients, both male and female, show comparable improvements. Unfortunately, referral to and participation in cardiac rehabilitation are less frequent in elderly patients, particularly elderly women. No complications or adverse outcomes for elderly patients were described in any study. Elderly patients of both sexes should be encouraged to participate in cardiac rehabilitation. Patients on dialysis and following coronary artery bypass grafting surgery Patients who are on renal dialysis are at high risk for cardiac death and have a large burden of cardiovascular disease and cardiovascular disease risk factors. Cardiac rehabilitation can promote improved survival of nondialysis patients after coronary artery bypass grafting (CABG) surgery and is covered by Medicare, but no previous studies have investigated whether dialysis patients' survival after CABG may be improved as a function of cardiac rehabilitation. In a 2006 study by Kutner et al, dialysis patients who received cardiac rehabilitation after CABG had a 35% reduced risk for all-cause mortality and a 36% reduced risk for cardiac death compared with dialysis patients who did not receive cardiac rehabilitation, independent of sociodemographic and clinical risk factors, including recent hospitalization. Only 10% of patients received cardiac rehabilitation after CABG, compared with an estimated 23.4% of patients in the general population, and lower-income patients of all ages as well as women and black patients aged 65 or older were significantly less likely to receive cardiac rehabilitation services. This observational study suggests a survival benefit of cardiac rehabilitation for dialysis patients after CABG. CARDIAC REHABILITATION: RISKS, SAFETY, AND COST ISSUES
Exercise training involves certain risks, especially in patients with undiagnosed or undertreated myocardial ischemia, ventricular arrhythmias, or LV dysfunction. The intensity of exercise must be kept below the level of exercise at which the abnormalities were elicited during the risk stratification and testing phase. Selection of patientsProper selection of patients is of paramount importance before beginning phase 2 or phase 3 exercise programs. Patients with certain characteristics are at a higher risk, and therefore, require all attempts at correction of the high-risk condition prior to exercise training. Patients also must be monitored with continuous ECG and supervised closely. These high-risk features include the following:
For some patients, the risks of exercise may outweigh the benefits. In these instances, patients should be counseled against exercise training, and their medical management must first be optimized with thorough supervision. Surveillance(A) High-risk patients, constituting approximately 15-25% of all patients referred for cardiac rehabilitation, require the maximum level of supervision and surveillance involving continual ECG monitoring. The group of high-risk patients described above constitutes the bulk of such patients. (B) Intermediate-risk patients need somewhat less intense surveillance. The level of supervision needed includes unmonitored exercise training in groups in the presence of health professionals who are certified in advanced cardiac life support (ACLS). (C) Very low-risk patients can exercise safely and independently, once they have learned how to monitor their pulse rates and are able to recognize warning signs. Such patients have greater than 8 METs of exercise capacity without symptoms or signs of angina, heart failure, or arrhythmias. (D) Alternative approaches to the traditional supervised cardiac rehabilitation programs have been evaluated and found to be reasonably safe. These off-site self-monitored or telemetry-monitored programs are applicable primarily to very low-risk patients and include (1) home-based cardiac rehabilitation (effective and safe) and (2) exercise with trans-telephonic surveillance. SafetySupervised exercise training programs have extremely good safety records, despite the inherent potential for cardiovascular complications during exercise. None of the more than 3 dozen randomized controlled trials of cardiac rehabilitation exercise testing and training in patients with coronary heart disease, involving over 4,500 patients, showed any increase in morbidity or mortality in rehabilitation compared with control patient groups. A 1980-1984 survey of 142 US cardiac rehabilitation programs reported a low rate of nonfatal myocardial infarction (1 case per 294,000 patient-hours) and cardiac mortality (1 case per 784,000 patient-hours). A total of 21 episodes of cardiac arrest occurred, out of which, 17 were successfully resuscitated. Therefore, the safety of exercise within cardiac rehabilitation programs is well accepted and established. Analysis of cost effectivenessCardiac rehabilitation is a clinically effective intervention for coronary heart disease that has been subjected to preliminary cost analyses. A randomized US 8-week trial of rehabilitation beginning 6 weeks following MI showed cost/effectiveness (C/E) of $9,200 per quality adjusted life year. A similar more recent analysis shows a C/E of only $4,950 per year of life saved. In contrast, cholesterol lowering for secondary prevention has a C/E of $9,630 per year of life saved, thrombolytic therapy of acute MI has a C/E of $32,700 per year of life saved, and bypass surgery has a C/E of $18,700 for a year of life saved. A comprehensive cost analysis of cardiac rehabilitation performed in Sweden in patients following MI or bypass surgery with 5-year follow-up showed rehospitalizations decreased from 16 to 11 days, and higher rate of return to work (53% versus 38%). Overall, cardiac rehabilitation programs resulted in cost savings to the Swedish system of $12,000 per patient. Therefore, cardiac rehabilitation is not only clinically effective, but it is cost effective as well. Cardiac rehabilitation compares favorably with other medical interventions performed commonly in patients with coronary heart disease. CONCLUSION
Cardiac rehabilitation is an important component of current multidisciplinary approach for management of the patients with various presentations of coronary heart disease. Cardiac rehabilitation involves exercise training, education, counseling regarding risk reduction and lifestyle modification, and, frequently, behavior interventions. The goals of cardiac rehabilitation services are to improve both the physiologic and psychosocial condition of the patients. Physiologic benefits include improvement of exercise capacity and reduction of risk factors (eg, cessation of smoking, lowering of lipid levels, body weight, blood pressure, blood glucose), where the exercise component provided through rehabilitation may cause reduction in the progression of atherosclerosis. Psychological improvements include reduction of depression, anxiety, and stress. All these improvements enable acquisition and maintenance of functional independence and return to satisfactory and appropriate activity that benefits both the patient and society. For excellent patient education resources, visit eMedicine's Cholesterol Center and Public Health Center. Also, see eMedicine's patient education articles Chest Pain, Coronary Heart Disease, Heart Attack, Walking for Fitness, and Strength Training. MULTIMEDIA
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Cardiac Rehabilitation excerpt Article Last Updated: Mar 28, 2006 | ||||||||||||||||||||||||||||