Cardiac Rehabilitation

Updated: Aug 12, 2015
  • Author: Vibhuti N Singh, MD, MPH, FACC, FSCAI; Chief Editor: Consuelo T Lorenzo, MD  more...
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Cardiac rehabilitation aims to reverse limitations experienced by patients who have suffered the adverse pathophysiologic and psychological consequences of cardiac events.

Cardiovascular 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), as well as the more than 300,000 patients who undergo coronary bypass surgery annually, are candidates for cardiac rehabilitation.

The image below depicts cardiac rehabilitation after bypass surgery.

Phase 1: A patient walking in the hallway with a p Phase 1: A patient walking in the hallway with a physical therapist following bypass surgery.

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 rehabilitation training. Currently, about 400,000 patients who undergo coronary angioplasty each year make up 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 who have undergone heart transplantation. [1]

This review addresses the objectives, indications, program components, exercise training, monitoring, benefits, risks, safety issues, outcome measures, and cost-effectiveness of cardiac rehabilitation.


The identification of the patients at risk for a cardiac event's recurrence (ie, risk stratification) is central to formulating an appropriate medical, rehabilitative, and surgical strategy to prevent such a recurrence. Patients who are at low or moderate risk typically undergo early rehabilitation. The major goals of a cardiac rehabilitation program are:

  • Curtail the pathophysiologic and psychosocial effects of heart disease
  • Limit the risk for reinfarction or sudden death
  • Relieve cardiac symptoms
  • Retard or reverse atherosclerosis by instituting programs for exercise training, education, counseling, and risk factor alteration
  • Reintegrate heart disease patients into successful functional status in their families and in society

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.


The Agency for Health Care Policy and Research (AHCPR); the American Association of Cardiovascular and Pulmonary Rehabilitation (AACVPR), and the National Heart, Lung and Blood Institute (NHLBI) 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.

In the past, it was found that only 11% of patients participated in such programs following an acute coronary event. However, there is evidence that participation 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 Measures

Current 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. [2] 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). [3, 4]

Similarly, among patients who are elderly, such outcome measures may include the achievement of functional independence, the prevention of premature disability, and a reduction in the need for custodial care. [5, 6, 7, 8] Despite limited data, older male and female patients in observational studies have shown improvement in their exercise tolerance comparable to that of 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.

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History and Definition of Cardiac Rehabilitation


In the 1930s, patients with myocardial infarction (MI) were advised to observe 6 weeks of bedrest. Chair therapy was introduced in the 1940s, and 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 bed rest, including pulmonary embolism (PE), and that it did not increase the risk. However, concerns about the safety of unsupervised exercise remained strong; this led to the development of structured, physician-supervised rehabilitation programs, which included clinical supervision, as well as electrocardiographic monitoring.

In the 1950s, Hellerstein presented his methodology for the comprehensive rehabilitation of patients recovering from an acute cardiac event. [9] He advocated a multidisciplinary approach to the rehabilitation program. His approach was adopted by 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.


According to the US Public Health Service (USPHS), a cardiac rehabilitation program is defined as a program that involves the following:

  • Medical evaluation
  • Prescribed exercise
  • Education
  • Counseling of patients with cardiac disease

Cardiac rehabilitation has to be comprehensive and, at the same time, individualized. The main goals of a cardiac rehabilitation program are noted below.

Short-term goals are as follows:

  • "Reconditioning" the patient sufficiently enough to allow him/her to resume customary activities
  • Limiting the physiologic and psychological effects of heart disease
  • Decreasing the risk of sudden cardiac arrest or reinfarction [10, 11]
  • Controlling the symptoms of cardiac disease

Long-term goals are as follows:

  • Identification and treatment of risk factors
  • Stabilizing or reversing the atherosclerotic process
  • Enhancing the psychological status of the patients

Physiology of Exercise and Cardiovascular Benefit

Coronary vasodilatation is mainly driven by the bioavailability of nitric oxide (NO), which is produced by the activities of the endothelially derived enzyme NO synthase and is metabolized by reactive oxygen species. This fine-tuned balance is disturbed in people with CAD. This form of impairment of NO production, along with excessive oxidative stress, results in the loss of endothelial cells via apoptosis. Further aggravation of endothelial dysfunction ensues, which triggers myocardial ischemia in persons with coronary artery disease (CAD). In healthy individuals, an 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 the cardiac rehabilitation of patients with CAD, because it reduces mortality and increases myocardial perfusion. This has been largely attributed to the exercise training–mediated correction of coronary endothelial dysfunction in persons with CAD. In persons with CAD, regular physical activity leads to a restoration of the balance between NO production by NO synthase and NO inactivation by reactive oxygen species, 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 behind the exercise training–induced reduction in cardiovascular morbidity and mortality in patients with CAD.

The amount of exercise in the year before cardiac surgery has been linked to the incidence of postoperative atrial fibrillation during rehabilitation according to a study by Giaccardi et al. The incidence of atrial fibrillation during rehabilitation was significantly higher in patients who performed low-intensity physical exercise the year before surgery compared with those who performed moderate-intensity exercise. The occurrence of atrial fibrillation during the patients' hospital stay, a larger left atrial volume, and a lower left atrial emptying fraction were independent predictors of atrial fibrillation during rehabilitation. [12]

Cardiac rehabilitation programs include walking as part of the exercise regimen. [13] Gremeaux et al studied the minimal clinically important difference for the 6-minute walk test and the 200-meter fast-walk test for 81 patients with acute coronary syndrome. [14] Results before and after an 8-week cardiac rehabilitation program, and at the 6th and 12th sessions, were reviewed. Patients were asked to rate the change in their walking ability between these two tests. Physiotherapists, who supervised the training, also gave their input. The minimal clinically important difference and mean change in the 6-minute walk test distance was 25 m; no difference was found in the 200-meter fast walk test. These results should help physicians interpret the changes made by their patients in a clinical context and also be used in further studies that use 6 MWD as a measure.

A study by Bellet et al indicated that cardiac rehabilitation patients may derive the same benefit from a program of once-weekly supervised exercise sessions as they do from a program of twice-weekly sessions. The study found that improvements in the 6-minute walk test distance were the same after 6 weeks of low to moderate intensity training in the once-weekly exercise group (115 patients) as in the twice-weekly group (254 patients). [15]

A study by El Demerdash et al indicated that in patients with ischemic heart disease who are not suitable for cardiac revascularization procedures, a cardiac rehabilitation program can reduce ischemic burden. In the study, 40 patients with ischemic heart disease who were unsuitable for percutaneous coronary intervention or coronary artery bypass grafting participated in a program that included twice-weekly, low-intensity exercise, as well as patient education, smoking cessation, and nutritional, medical, psychological, and sexual counseling. The investigators reported a reduction in the patients’ ischemic burden, as well as improvements in the subjects’ functional capacity and hemodynamic and metabolic profiles. [16]


Patient Selection and Risk Stratification

Patient Selection

Cardiac rehabilitation encompasses short-term and long-term goals that are to be achieved through exercise, education, and counseling. Patients generally fall into following categories:

  • Lower-risk patients following an acute cardiac event
  • Patients who have undergone coronary bypass surgery
  • Patients with chronic, stable angina pectoris
  • Patients who have undergone heart transplantation
  • Patients who have had percutaneous coronary angioplasty
  • Patients who have not had prior events but who are at risk because of a remarkably unfavorable risk factor profile
  • Patients with stable heart failure
  • Patients who have undergone noncoronary cardiac surgery
  • Patients with previously stable heart disease who have become seriously deconditioned by intercurrent, comorbid illnesses

The short-term goals of cardiac rehabilitation include the restoration of the physical, psychological, and social condition, while the long-term goals involve the 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. [17] Elderly patients also can derive significant benefit from rehabilitation programs.

Risk Stratification

The risk stratification process is very valuable for cardiac patients; it serves as the basis for individualizing the prescription of exercise training and for assessing the need and extent of supervision required. The risk stratification process is based on the assessment of the patient's functional capacity, on the patient's educational and psychosocial status, on whether alternatives to traditional cardiac rehabilitation can be used, and on whether the patient is suffering from myocardial ischemia, ventricular dysfunction, or arrhythmias.

Functional capacity

The term functional capacity refers to the maximum ability of the heart and lungs to deliver oxygen and the ability of the muscles to extract it. Functional capacity is measured by determining the maximal oxygen uptake (VO2 max) during incremental exercise.

In most patients, a rough calculation of functional capacity can be performed by using multiples of 1 MET (metabolic equivalent, 3.5 mL O2 uptake/kg/min). In complicated patients, such as those with severe left ventricular (LV) dysfunction and congestive heart failure (CHF), the functional capacity can be ascertained with greater accuracy by using cardiopulmonary exercise (CPX) testing. Most cardiac rehabilitation facilities, however, are not currently equipped for CPX.

The following factors influence functional capacity:

  • Age
  • Precardiac event physical capacity
  • Treatments and bed rest during the event
  • Fluid volume, such as relative dehydration or volume overload in patients with CHF
  • LV dysfunction
  • Residual myocardial ischemia
  • Skeletal muscle performance, such as deconditioning or in the presence of concurrent, noncardiac illness
  • Autonomic function, such as diabetic neuropathy
  • Peripheral vascular status
  • Pulmonary status
  • Other systemic illnesses, especially orthopedic problems limiting flexibility and locomotion

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.

Myocardial ischemia

Symptomatic or asymptomatic (silent) myocardial ischemia may limit the patient's exertional capacity by causing limiting angina, dyspnea, or fatigue.

Ventricular dysfunction

Fixed LV dysfunction or damage may be present in the absence of angina. Patients with LV dysfunction develop early dyspnea and easily become fatigued.

Cardiopulmonary exercise testing preferably should be performed to determine the functional capacity in an objective manner.

Exercise intolerance in patients with LV dysfunction is due to skeletal muscle hypoperfusion resulting from inadequate cardiac output that can be better quantified by measuring VO2 max.


Ventricular irritability and complex ventricular arrhythmias require assessment through the use of signal-averaged electrocardiogram (ECG) or electrophysiologic studies.

Appropriate medical or device treatments should be undertaken whenever feasible prior to beginning phase 2 of the cardiac rehabilitation program.

Very close surveillance is necessary in patients with significant cardiac arrhythmias during their exercise training routines. Concomitant rhythm monitoring with telemetry, Holter or event monitoring should be considered. In many cases of serious arrhythmias, therapy remains controversial and the safety of is exercise unclear; such uncertainties complicate the decision-making process.

Patients with severe ventricular arrhythmias and uncontrolled supraventricular arrhythmias should be excluded from exercise training unless proper evaluation and effective therapy has been instituted. Patients with devices, such as pacemakers and defibrillators, should be carefully monitored during exercise. Rate-responsive pacemakers are quite helpful even for those patients who are completely pacemaker-dependent. In case of implantable cardioverter defibrillators (ICDs), exercise training can be provided as long as underlying arrhythmias are controlled with pharmacotherapy. Heart rate should be kept well below the threshold at which the antitachycardia algorithm of the ICD begins.

Educational and psychosocial status

Approximately 20-25% of acute myocardial infarction (MI) patients demonstrate severe psychological stress or major depression; they also show higher morbidity and mortality. [18] Clinically significant depressive symptoms are found in 40-65% of patients after an MI.

Exercise does provide some benefit, but severe cases may require specific therapy that has been shown to enhance the benefits derived from subsequent cardiac rehabilitation.

The promotion of self-efficacy and control over one's activities is of paramount importance for boosting self-confidence.

Coronary-prone behavior (CPB) is known as a cardiac risk factor, but its effect on prognosis is unclear. Some data suggest that the modification of CPB can improve the coronary disease prognosis.

Initially, continuous ECG monitoring is recommended for most patients during cardiac rehabilitation exercise training; however, clinicians may decide whether to use continuous or intermittent ECG monitoring. After the initial period, the use of electrocardiography depends on the clinical judgment of the supervising physician.

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, which are applicable primarily to very low-risk patients, include the following options:

  • Home-based cardiac rehabilitation (effective and safe)
  • Exercise with transtelephonic monitoring/surveillance

Cardiac Rehabilitation in Patients with Heart Failure

Heart rate recovery (HRR) following maximal exercise has been found to be a predictor of all-cause mortality. In a 2006 study, Streuber and colleagues hypothesized that aerobic exercise training could improve HRR in patients who have suffered heart failure, because athletes are known to have accelerated HRR, while cardiac rehabilitation has been shown to positively effect such recovery in patients with coronary artery disease (CAD). [19] The authors 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 in patients with heart failure who have low exercise capacity, even short-term aerobic training can aid HRR.


Exercise Testing and Exercise Prescription


Cardiac 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 congestive heart failure (CHF), the indications have been expanded to include such patients. Exercise training benefits persons with the following cardiac conditions:

  • Recent myocardial infarction
  • Coronary bypass [20]
  • Valve surgery [21]
  • Coronary angioplasty
  • Cardiac transplantation [21]
  • Angina
  • Compensated CHF

Exercise prescription depends on the results of exercise testing, which often includes cardiopulmonary exercise (CPX) testing.

Modifications of Exercise

Patients 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).


Cardiac rehabilitation services are contraindicated in patients with the following conditions:

  • Severe residual angina
  • Uncompensated heart failure
  • Uncontrolled arrhythmias
  • Severe ischemia, LV dysfunction, or arrhythmia during exercise testing
  • Poorly controlled hypertension
  • Hypertensive or any hypotensive systolic blood pressure response to exercise
  • Unstable concomitant medical problems (eg, poorly controlled or "brittle" diabetes, diabetes prone to hypoglycemia, ongoing febrile illness, active transplant rejection) [22]

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 Testing

Two 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

In this strategy, the patients exercise enough to achieve 70% of maximum predicted heart rate for their age (ie, 70% of 220 minus age in years).

This test is commonly performed prior to discharge and is followed by maximal exercise testing 6-8 weeks later (when patients aim to achieve 90% of maximum predicted heart rate).

Symptom-limited exercise testing

The patients exercise soon after a cardiac event.

A representative schedule might begin exercise at intervals, such as 7-21 days following uncomplicated acute myocardial infarction (MI), 3-10 days following angioplasty, or 14-28 days after bypass surgery.

Submaximal exercise testing is not necessarily safer than symptom-limited testing. In fact, the submaximal strategy may have certain disadvantages; it can lead to inappropriate limitation in the patient's routine activities and exercise training and to a significant delay in the patient's return to work. The use of submaximal exercise may also result in a failure to elicit important factors in prognosis, such as ischemia, cardiac dysfunction, and arrhythmia.

CPX testing

Incremental exercise is employed, using modified Naughton protocol for treadmill or modified protocols on a bicycle ergometer.

Concomitant minute-to-minute breath analysis and measurement of oxygen consumption and elimination of carbon dioxide are performed to determine VO2 max, which is the most objective method of determining functional capacity in patients with cardiac dysfunction, valvular disease, or recent acute cardiac event.

Modified Bruce or Naughton protocols typically are used during the testing phase, because the standard Bruce protocol has been modified to avoid too abrupt an increase in METs (by 2-3 METs per stage).

The modified Naughton protocol starts at a lower MET workload and increases by 1 MET per stage, thus allowing better-tolerated gradual progression in exercise and a more accurate assessment of exertional capacity.

The usual symptomatic endpoints are fatigue and breathlessness.

Severe abnormalities found on stress testing may contraindicate exercise training until they have been corrected. Less severe abnormalities, such as the development of the above symptoms at high workloads, may not necessarily contraindicate exercise training; however, certain modifications and closer surveillance may be required, including ECG monitoring.

Some reports have questioned early exercise training following acute anterior MI, suggesting that it may lead to abnormal scar formation. Nonetheless, evidence is strong that moderate exercise training is not associated with worsening LV function in patients following acute anterior MI.

Exercise Prescription and Surveillance

Phase 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 listed below.

The minimum frequency for exercising to improve cardiovascular fitness is 3 times weekly.

Patients usually need to allow 30-60 minutes for each session, which includes a warm-up of at least 10 minutes

The intensity prescribed is in relation to one's target heart rate. Aerobic conditioning is emphasized in the first few weeks of exercise. Strength training is introduced later. The Borg scale of Rate of Perceived Exertion (RPE) is used. Patients usually should exercise at an RPE of 13-15.

The Borg scale of perceived exertion is as follows:

  • 6
  • 7 - Very, very light
  • 8
  • 9 - Very light
  • 10
  • 11 - Light
  • 12
  • 13 - Somewhat hard
  • 14
  • 15 - Hard
  • 16
  • 17 - Very hard
  • 18
  • 19 - Very, very hard
  • 20 - Exhaustion

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 to 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.


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.

Also, in those with type 2 diabetes who have a hypertensive response to exercise, an increased left ventricular mass, and a higher risk of mortality, exercise training and dietary restrictions are advised. Schultz et al determined in their study that, after 1 year of these lifestyle modifications, patients significantly diminished their exercise blood pressure; however, their cardiac size remained the same. [23]


Phases of Cardiac Rehabilitation

Cardiac rehabilitation services are divided into 3 phases, as follows:

  • Phase 1 - Initiated while the patient is still in the hospital
  • Phase 2 - A supervised ambulatory outpatient program spanning 3-6 months
  • Phase 3 - A lifetime maintenance phase in which physical fitness and additional risk-factor reduction are emphasized

Phase 1: in-hospital phase

This program begins while patients are still in the hospital.

Phase 1 includes a visit by a member of the cardiac rehabilitation team, education regarding the disease and the recovery process, personal encouragement, and inclusion of family members in classroom group meetings. See the images shown below.

Phase 1: A patient walking in the hallway with a p Phase 1: A patient walking in the hallway with a physical therapist following bypass surgery.
Phase 1 and 2: Education and counseling one-on-one Phase 1 and 2: Education and counseling one-on-one with patient and family.

Some older patients may serve as volunteers and share their experiences about learning to live with heart disease.

Team members include cardiac nurses, exercise specialists, physical therapists, occupational therapists, dietitians, and social workers.

In the coronary care unit, assisted range-of-motion exercises can be initiated within the first 24-48 hours.

Low-risk patients should be encouraged to sit in a bedside chair and to begin performing self-care activities (eg, shaving, oral hygiene, sponge bathing).

On transfer to the step-down unit, patients should, at the beginning, try to sit up, stand, and walk in their room. Subsequently, they should start to walk in the hallway at least twice daily either for certain specific distances or as tolerated without being unduly pushed or held back. Standing heart rate and blood pressure should be obtained followed by 5 minutes of warm-up or stretching. Walking, often with assistance, is resumed, with a target heart rate of less than 20 beats above the resting heart rate and an RPE of less than 14. Starting with 5-10 minutes of walking each day, exercise time gradually can be increased to up to 30 minutes daily.

Team members including the nurse educator, dietitian, exercise rehabilitation trainer, and physician should incorporate in the discharge planning an appropriate emphasis on secondary prevention through risk factor modification and therapeutic lifestyle changes (TLC), such as aspirin and beta-blocker use in all patients, angiotensin converting enzyme (ACE) inhibitor use in patients with left ventricular ejection fraction of less than 40%, smoking cessation, lipid management, weight management, and stress management. They must also ensure that phase 1 patients get referred to appropriate local, convenient, and comprehensive phase 2 programs.

Phase 1.5: postdischarge phase

This phase begins after the patient returns home from the hospital.

Better understanding of how to keep the heart healthy and strong is emphasized. Team members work with patients and family members.

Team members check the patient's medical status and continuing recovery; they should offer reassurance as the patient regains health and strength.

This phase of recovery includes low-level exercise and physical activity, as well as instruction regarding changes for the resumption of an active and satisfying lifestyle.

Risk reduction strategies are emphasized again.

After 2-6 weeks of recovery at home, the patient is ready to start phase 2 of his/her cardiac rehabilitation.

Phase 2: supervised exercise

Patients who have completed hospitalization and 2-6 weeks of recovery at home can begin phase 2 of their cardiac rehabilitation program.

The physician and cardiac rehabilitation staff members formulate the level of exercise necessary to meet an individual patient's needs (see images below).

Phase 2: Exercise testing and training on a treadm Phase 2: Exercise testing and training on a treadmill.
Cardiopulmonary exercise testing to objectively de Cardiopulmonary exercise testing to objectively determine the functional capacity in patients with congestive heart failure before they begin a rehabilitation exercise program.

Exercise treatments usually are scheduled 3 times a week at the rehabilitation facility.

Constant medical supervision is provided; this includes supervision by a nurse and an exercise specialist, as well as the use of exercise ECGs.

In addition to exercise, counseling, and education about stress management, smoking cessation, nutrition, and weight loss also are incorporated into this phase.

Phase 2 may last 3-6 months.

Phase 3: maintenance phase

Phase 3 of cardiac rehabilitation is a maintenance program designed to continue for the patient's lifetime. The exercise sessions usually are scheduled 3 times a week.

Activities consist of the type of exercises the patient enjoys, such as walking, bicycling, or jogging. A registered nurse supervises these classes.

ECG monitoring usually is not necessary.

The main goal of phase 3 is to promote habits that lead to a healthy and satisfying lifestyle.

Phase 3 programs do not usually require medical or nursing supervision. In fact, most patients participate in "phase 3" equivalent exercises at the exercise facilities in the community (eg, YMCA, YWCA).

Sexual activity

Common sexual problems encountered by cardiac patients include impotence, premature or delayed ejaculation, and reduced libido (in men and women). These difficulties may be due to medications (eg, beta blockers, diuretics), depression, or fears by the patient and his or her partner of precipitating a cardiac event.

Maximum heart rate during sexual intercourse averages 120 bpm, which is similar to heart rates associated with other routine activities in and around the house.

The hemodynamic response is greater with an unfamiliar sex partner, in unfamiliar surroundings, after eating, or after consuming alcohol.

Adapting less strenuous positions — for example, using a side-to-side arrangement rather than the missionary position — can reduce cardiac stress.

Patients may start sexual activity 2-3 weeks following an uncomplicated myocardial infarction. They must be instructed to report any untoward symptoms to the physician or to a member of the rehabilitation team.


Outcomes of Cardiac Rehabilitation Training

Cardiac rehabilitation provides many benefits for patients. The most important of these are discussed in this section.

Improved exercise tolerance

Cardiac rehabilitation exercise training for patients with coronary heart disease or congestive heart failure (CHF) leads to objectively verifiable improvement in exercise capacity in men and women, regardless of age. [17] 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. [24] 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. [25] 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. [26]

Effect on blood pressure

Rehabilitation 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 educational services enhance measures of psychological and social functioning. [3, 4]

Reduction of stress

In multifactorial cardiac rehabilitation programs, improvement in emotional-stress measurements occurs, as does a 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.

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 post–myocardial infarction (MI), randomized, controlled trials of exercise showed a 25% reduction in mortality at 3-year follow-up. The magnitude of this benefit is as large as that seen with the post-MI use of beta blockers or with the use of ACE inhibitors in LV dysfunction along with MI. Trials that involve exercise alone still show a 15% mortality reduction.

The scientific evidence pertaining to the relationship between cardiac rehabilitation exercise training and mortality also includes scientific reports that have appeared on the US National Institutes of Health Web site. Among the data in these reports was the finding, through randomized trial, that 3-year coronary mortality and sudden death rates were significantly lower (P < .02) in patients who, after suffering myocardial infarction, underwent multifactorial cardiac rehabilitation, starting 2 weeks after hospital discharge. This beneficial outcome persisted at the 10-year follow-up.

The larger center from a multicenter European trial of exercise-only rehabilitation in males (post-MI) reported significant mortality reduction in the rehabilitation group (P < .01).

Pathophysiologic measures

When combined with intensive dietary intervention, with or without lipid-lowering drugs, exercise training may result in the limitation of progression or in the regression of angiographically documented coronary atherosclerosis.

Exercise training in patients with heart failure and compromised LV ejection fraction produces favorable hemodynamic changes in the skeletal musculature. Therefore, cardiac rehabilitation exercise training is recommended for the improvement of skeletal muscle functioning. However, such training does not seem to improve cardiac hemodynamic function or collateral circulation to any significant degree.

Patients following cardiac transplantation

Following orthotropic cardiac transplantation, rehabilitation exercise training is recommended to improve patients' exercise tolerance measurements. [21]

Elderly patients and women

Coronary patients who are elderly have exercise trainability comparable to that of younger patients participating in similar rehabilitation programs. Elderly patients (male and female) show comparable improvements. Unfortunately, referrals to cardiac rehabilitation are made less frequently for elderly patients, particularly for elderly women; participation in cardiac rehabilitation also is less frequent among the elderly. No complications or adverse outcomes for elderly patients have been described in any study. Elderly male and female patients 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, [20] but no studies have investigated whether dialysis patients' survival after CABG may be improved as a function of cardiac rehabilitation.

In a 2006 study by Kutner and colleagues, it was found that, in comparison with dialysis patients who did not undergo cardiac rehabilitation, there was a 35% risk reduction for all-cause mortality, as well as a 36% risk reduction for cardiac death, in dialysis patients who had cardiac rehabilitation following CABG; the findings were independent of sociodemographic and clinical risk factors, such as recent hospitalization. [27] In the study, 10% of patients received cardiac rehabilitation after CABG, less than half the estimated share of patients in the general pouplation who such rehabilitation. Women and black patients aged 65 or older, along with lower-income patients of all ages, were significantly less likely to receive cardiac rehabilitation services. This observational study suggests that following CABG, cardiac rehabilitation increases a dialysis patient's likelihood of survival.


Cardiac Rehabilitation: Risks, Safety, and Cost Issues

Overview 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 Patients

The proper selection of patients is of paramount importance before phase 2 or phase 3 exercise programs are begun. [28] 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 electrocardiography and be supervised closely. High-risk factors include the following:

  • Severe LV dysfunction, LV ejection fraction (EF) less than 30%, congestive heart failure (CHF), and history of cardiogenic shock
  • Severe exercise-induced ischemia (such as angina at a workload of less than 5 METs), ST-segment depression of greater than 0.2 mV on an ECG, multiple perfusion defects on exercise nuclear stress testing, or multiple dyskinetic LV segments on stress echocardiography
  • Complex ventricular arrhythmias, such as nonsustained ventricular tachycardia (a less than 30-second run of ventricular tachycardia [VT]) at rest or with exercise or a history of previous sudden cardiac arrest (SCA)
  • Hypotensive response to exercise (ie, drop in systolic pressure of more than 20 mm Hg at incremental exertion)
  • Low functional capacity (ie, peak workload of less than 5 METs, functional capacity determined by CPX testing with reduced peak oxygen [VO 2 max] consumption)
  • Patient's inability to self-monitor his/her heart rate

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.


High-risk patients, constituting approximately 15-25% of all patients referred for cardiac rehabilitation, require the maximum level of supervision and surveillance, including continual ECG monitoring. The group of high-risk patients described above constitutes the bulk of such patients.

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).

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.

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.


Supervised 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 (MI; 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, with resuscitation successfully performed in 17 of these episodes. Therefore, the safety of exercise within cardiac rehabilitation programs is well accepted and established.

Analysis of Cost-Effectiveness

Cardiac rehabilitation, a clinically effective intervention for coronary heart disease, has been subjected to preliminary cost analyses. [6, 29] In a US study, a randomized, 8-week trial of rehabilitation beginning 6 weeks following MI showed a cost-effectiveness of $9,200 per quality adjusted life year. Subsequently, a similar analysis showed a cost-effectiveness of only $4,950 per year of life saved. In contrast, cholesterol lowering for secondary prevention has a cost-effectiveness of $9,630 per year of life saved, thrombolytic therapy for acute MI has a C/E of $32,700 per year of life saved, and bypass surgery has a cost-effectiveness of $18,700 for a year of life saved.

In Sweden, a comprehensive cost analysis of cardiac rehabilitation, performed on patients following MI or bypass surgery (with a 5-year follow-up), showed that rehospitalizations decreased from 16 to 11 days; the study also showed a 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.

Research therefore indicates that cardiac rehabilitation is not only clinically effective, but is cost-effective as well. Cardiac rehabilitation compares favorably with other medical interventions performed commonly in patients with coronary heart disease.



Cardiac rehabilitation is an important component of the current multidisciplinary approach to the 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 the physiologic and psychosocial condition of patients. Physiologic benefits include the improvement of exercise capacity and the reduction of risk factors (eg, cessation of smoking and lowering of lipid levels, body weight, blood pressure, blood glucose), with the exercise component provided through rehabilitation possibly reducing the progression of atherosclerosis. Psychological improvements include the reduction of depression, anxiety, and stress. All of these improvements enable the patient to acquire and maintain functional independence and to return to satisfactory and appropriate activity that benefits the patient and society.

For excellent patient education resources, visit eMedicineHealth's Healthy Living Center. Also, see eMedicineHealth's patient education articles Chest Pain, Coronary Heart Disease, Heart Attack, Walking for Fitness, and Resistance Training.