Cardiac rehab: who to refer and what it changes

A 58-year-old man is discharged three days after an angioplasty for a heart attack. The prescription is complete: antiplatelets, statin, beta-blocker. In the discharge summary, the line about cardiac rehabilitation was left blank. At the follow-up visit, he says he is afraid to climb stairs, has started smoking two cigarettes a day again, and does not know if he can walk again.

The scene is common. Cardiac rehabilitation is one of the most studied interventions in cardiology, and yet only a minority of eligible people participate (Thomas, 2019). The problem is rarely with the patient alone: it starts with the referral that does not happen.

This text shows who has an indication, what systematic reviews found in each patient group, what the most frequent barriers are, and what works to increase referral and adherence.

Key points

• In coronary artery disease, exercise-based rehabilitation reduced cardiovascular death, heart attack, and hospitalizations in a meta-analysis of 85 trials (Dibben, 2023).
• All-cause mortality changed little in these trials, and the benefit appears mainly in cardiovascular events (Dibben, 2021).
• In heart failure, rehabilitation reduced hospitalizations for any cause and improved quality of life (Molloy, 2024).
• Automatic referral in the medical record reached 85 out of every 100 eligible patients referred (Gravely-Witte, 2010).
• Women, minorities, and rural residents are referred and participate less (Mathews, 2021).
• Home-based rehabilitation had exercise capacity gains similar to those of the in-person program in low- to moderate-risk patients (Thomas, 2019).

Summary

• What cardiac rehabilitation is
• Who has an indication
• What Cochrane shows in coronary artery disease
• Heart failure, valve disease, and atrial fibrillation
• Why so few get there
• What increases referral and adherence
• How to refer in practice
• How NEXO helps train this reasoning
• Frequently asked questions
• Take-home messages

What cardiac rehabilitation is

More than supervised exercise

Cardiac rehabilitation is a structured program, and exercise is only one part of it. American societies describe five core components: patient assessment, physical training, dietary guidance, risk factor control, and psychosocial intervention (Thomas, 2019). Risk factor control includes smoking, lipids, blood pressure, weight, and diabetes (Thomas, 2019).

In practice, this means that the patient in the example would find, in the same place, someone to prescribe and monitor exercise, someone to resume the conversation about smoking, and someone to address the fear of moving again. For smoking, the brief approach described in the text on counseling at every visit also fits within rehabilitation.

Delivery models

The classic model is in-person, with supervised sessions at a center. Trials have also tested home programs, with telephone contact, visits, or remote monitoring (Thomas, 2019). In the coronary artery disease meta-analysis, 21 programs were home-based, and four of them were delivered by mobile phone or internet (Dibben, 2023).

Who has an indication

Coronary artery disease

In international guidelines, exercise-based rehabilitation is a class I, level A recommendation for coronary artery disease (Dibben, 2023). This places it on the same level as other measures expected in the discharge prescription, and the absence of referral should draw as much attention as the lack of a statin.

The most studied group is people with coronary artery disease. Trials included mainly heart attack survivors and people who underwent surgical revascularization or angioplasty (Dibben, 2021). The meta-analysis also accepted angina and coronary artery disease confirmed by testing (Dibben, 2023).

Heart failure

The second major indication is heart failure. The most recent Cochrane review gathered 60 trials with 8728 participants (Molloy, 2024). The indication is separate from coronary artery disease because the patient profile, outcomes, and effect size differ.

Valve surgery and atrial fibrillation

There is less evidence for people who have had valve surgery and for those with atrial fibrillation. In valve surgery, the Cochrane review found only six trials with 364 participants (Abraham, 2021). In atrial fibrillation, there were 20 trials with 2039 participants (Buckley, 2024).

What links these groups is the recommendation to consider rehabilitation already when planning discharge. The American statement summarizes that the programs reduce morbidity and mortality in adults with ischemic disease, heart failure or cardiac surgery (Thomas, 2019).

What Cochrane shows in coronary disease

Size of the evidence

The 2021 Cochrane review included 85 trials with 23,430 people with coronary disease (Dibben, 2021). Median follow-up was 12 months (Dibben, 2023). The findings were consistent with the previous version of the review, from 2016 (Dibben, 2021).

Cardiovascular death, heart attack and hospitalization

At the longest follow-up, exercise-based rehabilitation reduced cardiovascular death, with a relative risk of 0.74 (Dibben, 2023). Hospitalizations also fell, with a relative risk of 0.77, and heart attack had a relative risk of 0.82 (Dibben, 2023).

The number needed to treat helps translate these effects. It took rehabilitating 37 people to prevent one cardiovascular death and 37 to prevent one hospitalization (Dibben, 2023). To prevent one heart attack, it was 100 people (Dibben, 2023).

At long-term follow-up, the reduction in cardiovascular death was large, with a relative risk of 0.58 (Dibben, 2021). Fatal or non-fatal heart attack also fell substantially in the long term, with a relative risk of 0.67 (Dibben, 2021).

What changed little

All-cause mortality changed little. At the longest follow-up, the relative risk was 0.96, with a confidence interval that crosses 1 (Dibben, 2023). The need for repeat revascularization surgery also showed no difference, with a relative risk of 0.96 (Dibben, 2023).

This distinction matters in the conversation with the patient. Saying that rehabilitation "saves lives" in a generic way is less precise than saying that it reduces heart attack, hospitalization and cardiac death.

Quality of life

Quality of life improved in six of the eight domains of the SF-36 questionnaire (Dibben, 2023). The authors themselves note that the gains in each domain were below the minimum clinically important difference, while the EQ-5D visual scale may have had a relevant gain (Dibben, 2023).

Why hospitalization weighs so much

The reduction in hospitalizations brings benefit to the health service, through the use of resources, and to the patient, who returns home sooner, to family and to the support network (Dibben, 2023). For those who decide on offering programs, this is one of the most concrete arguments.

The programs in the meta-analysis varied in duration, frequency and intensity, and the effect showed no significant difference between patient profiles, delivery models and program intensity (Dibben, 2023). This allows adapting the format to the local reality instead of waiting for the ideal model.

The question about today's patients

An old criticism is that the trials were of low-risk patients, from rich countries and from before modern therapy (Dibben, 2023). The meta-analysis explored this question and concluded that the benefits generalize across patient profiles and delivery models (Dibben, 2023).

Heart failure, valve and atrial fibrillation

Heart failure: hospitalizations

In heart failure, exercise-based rehabilitation probably reduced all-cause hospitalizations, with a relative risk of 0.69 (Molloy, 2024). Hospitalizations for heart failure had a relative risk of 0.82, with a wide interval (Molloy, 2024).

Heart failure: mortality

At up to 12 months, all-cause mortality showed no clear difference, with a relative risk of 0.93 (Molloy, 2024). In absolute numbers, there were 58 deaths per 1000 people in usual care and 50 per 1000 with exercise, with low certainty (Molloy, 2024).

Heart failure: quality of life

The clearest effect was on quality of life measured by the Minnesota Living with Heart Failure questionnaire (Molloy, 2024). The average improvement was 7.39 points in the short term, above the 5 points considered clinically important (Molloy, 2024). In the long term, the improvement was 9.49 points (Molloy, 2024).

For people living with shortness of breath and fatigue, this difference is often what the person feels in daily life. The conversation about new medications, such as the one in the text on finerenone in heart failure, sits alongside rehabilitation, and one does not replace the other.

Heart failure: who was left out of the trials

Most trials included people with reduced ejection fraction, in functional classes II and III, in in-person programs (Molloy, 2024). Women, older adults and people with preserved ejection fraction were underrepresented (Molloy, 2024). This point matters because about half of people with heart failure have preserved ejection fraction (Molloy, 2024).

More recent trials already include people with preserved ejection fraction, often in home-based programs (Molloy, 2024). For the clinician, the message is to refer these patients too, knowing that the estimate of benefit comes mainly from another profile.

After valve surgery

After valve surgery, the evidence is small and uncertain. In the Cochrane review, quality of life at the end of the intervention showed no clear difference, with very low certainty (Abraham, 2021). Exercise capacity measured in a maximal test improved at the end of the intervention, but the distance in the six-minute walk test showed no clear difference (Abraham, 2021). Because there are few and small trials, the decision to refer after valve surgery relies more on functional recovery than on hard outcomes (Abraham, 2021).

In atrial fibrillation

In atrial fibrillation, rehabilitation had little or no effect on mortality, with a relative risk of 1.06 in nine trials (Buckley, 2024). Arrhythmia recurrence measured by Holter probably fell, with a relative risk of 0.70 in four trials (Buckley, 2024). Symptom severity and exercise capacity may also improve (Buckley, 2024). Peak oxygen consumption rose by an average of 3.18 mL/kg/min, and the distance in the six-minute walk test increased by 50.79 meters, with low certainty (Buckley, 2024). The effects were similar between in-person and home-based programs and between exercise alone and full programs (Buckley, 2024).

Serious adverse events showed no clear difference, with a relative risk of 1.30 and a wide interval (Buckley, 2024). This reinforces the idea that supervised exercise is a safe option to consider, even when the evidence on hard outcomes is still limited.

Why so few get there

The referral that does not happen

Between 2007 and 2011, only 16.3 out of every 100 Medicare beneficiaries and 10.3 out of every 100 veterans took part in rehabilitation after myocardial infarction, angioplasty or coronary artery bypass surgery (Thomas, 2019). The lack of a physician recommendation appears among the barriers described for years (Dunlay, 2009).

The barriers cited by patients

In an American study, the concerns most cited by patients were cost and lack of coverage, in 27.9 out of every 100 (Dunlay, 2009). Then came the perception of inconvenience, in 20.1 out of every 100, lack of time and lack of transportation, both in 14.0 out of every 100 (Dunlay, 2009). Depression, low education and lack of motivation also appear as barriers (Dunlay, 2009).

Listening to these barriers is part of the consultation. The technique of eliciting the patient's agenda helps to uncover, for example, that the problem is the bus and not a lack of willingness.

Women

Women are less likely to be referred, with an odds ratio of 0.68, and to enroll after referral, with an odds ratio of 0.64 (Supervía, 2017). They also complete the program less often (Supervía, 2017). Among the barriers described are more comorbidities, lack of social support and many family responsibilities (Supervía, 2017).

The delay women face in the diagnosis of infarction, described in the text about the delay within the health service, continues after discharge. Women-only programs have been tested in few studies and may offer more flexibility (Supervía, 2017).

Minorities and rural areas

In the United States, Black, Hispanic and Asian patients were referred less often than white patients (Mathews, 2021). Among almost 360,000 Medicare beneficiaries with an indication, these groups also enrolled less (Mathews, 2021). Residents of rural areas, even when referred, complete the program less often (Mathews, 2021).

The authors point to paths forward: programs built with the community, strategies with incentives and home-based programs, which in small studies appear to improve attendance and completion (Mathews, 2021). In American registries, overall referral rose over the years, but differences between groups persisted (Mathews, 2021).

What increases referral and adherence

Automatic referral

Automatic referral uses the electronic health record or a standardized discharge prescription (Gravely-Witte, 2010). In studies with this strategy, referral reached 85 out of every 100 patients (Gravely-Witte, 2010). In one of the studies, automatic electronic referral reached 67 out of every 100, against 34 out of every 100 with usual referral (Gravely-Witte, 2010).

The conversation before discharge

The strategy called liaison is a personal conversation between a health professional and the patient about rehabilitation (Gravely-Witte, 2010). The highest enrollment came from combining automatic referral with this conversation, which reached 78 to 86 out of every 100 patients (Gravely-Witte, 2010).

The shape of the conversation matters. Asking what the person knows and what they fear, instead of just handing over a piece of paper, follows the logic of motivational interviewing.

Rehabilitation at home

Home-based rehabilitation widens access for those who live far away or work. In at least 20 reviewed studies, the improvement in peak oxygen consumption was similar to that of the in-person program (Thomas, 2019). Safety also appeared similar, at least in the low- to moderate-risk patients included in most studies (Thomas, 2019).

The caveat is that these studies selected low- to moderate-risk patients who were motivated and able to use technology (Thomas, 2019). Higher-risk patients remain preferential candidates for the in-person program.

How to refer in practice

A summary by indication

Indication	What the evidence shows	Strength of evidence
Coronary artery disease	Cardiovascular death with a relative risk of 0.74 and hospitalization with 0.77 (Dibben, 2023)	85 trials (Dibben, 2023)
Heart failure	Hospitalization for any cause with a relative risk of 0.69 and a 7.39-point improvement in quality of life (Molloy, 2024)	60 trials (Molloy, 2024)
Valve surgery	Quality of life with no clear difference, with very low certainty (Abraham, 2021)	6 trials (Abraham, 2021)
Atrial fibrillation	Recurrence with a relative risk of 0.70, mortality with no difference (Buckley, 2024)	20 trials (Buckley, 2024)

Applying it to the case

Returning to the 58-year-old man, the indication is clear: infarction treated with angioplasty is the most studied scenario (Dibben, 2021). The missing step was the referral, and the most effective solution is for him to leave discharge already referred, with a conversation explaining what the program is for (Gravely-Witte, 2010).

At follow-up, it is worth asking what prevents participation. If it is transport or work hours, home-based rehabilitation may be an alternative for those at low to moderate risk (Thomas, 2019). Smoking returns to the agenda as part of risk factor control, one of the central components of the program (Thomas, 2019).

What to tell the patient

Many patients leave the hospital afraid of exertion, like the man in the example. Explaining that the program starts with an assessment and supervised training, adjusted to each person's condition, addresses that fear (Thomas, 2019). It also helps to state concretely what rehabilitation changes: fewer hospitalizations and fewer deaths from cardiac causes (Dibben, 2023).

In heart failure, the strongest argument is usually quality of life, which improved by a clinically important margin (Molloy, 2024). Anyone who has already had fainting or palpitations during exertion needs an assessment first, and the reasoning in the text on syncope in the emergency department helps separate the cardiac causes.

Finally, the person needs to know that rehabilitation is part of the treatment, alongside medications, and that the decision to take part is theirs. Asking what they think of the program opens space to talk about barriers (Dunlay, 2009).

Checklist at discharge

• Was the indication recorded in the discharge summary?
• Did the referral go out together with the prescription?
• Did someone talk to the patient about the program?
• Were the barriers of transport, cost and schedule asked about?
• Is there a home option for those who cannot go to the center?

The limits of the evidence

Many of the trials were conducted in high-income countries, with low-risk patients (Dibben, 2023). For valve disease and atrial fibrillation, the reviews are small and the conclusions uncertain (Abraham, 2021). The studies on referral are mostly observational (Gravely-Witte, 2010). To avoid excessive testing before clearing exercise, it is worth recalling the principles of quaternary prevention.

How NEXO helps train this reasoning

In NEXO, the case of the day is fictional, with a real clinical presentation and up to six progressive clues, and you propose the diagnosis by looking for the code in ICD-10.

The limits on using the game are described on the NEXO economy page. If you research the teaching of clinical reasoning, the page for researchers explains how to get in touch. Professionals who write or review cases find information under curation and under creators, and institutions can learn about the proposal on the partnerships page. For the most frequent reasons for consultation, see the most common codes in primary care.

Frequently asked questions

Who should be referred to cardiac rehabilitation?

People with coronary artery disease, including heart attack, angioplasty and bypass surgery, and people with heart failure are the groups with the most evidence (Thomas, 2019). Valve surgery and atrial fibrillation have less evidence (Buckley, 2024).

Does rehabilitation reduce mortality?

It reduces cardiovascular death in coronary artery disease, with a relative risk of 0.74 (Dibben, 2023). All-cause mortality changed little (Dibben, 2023).

What is the benefit in heart failure?

Fewer hospitalizations for any cause and better quality of life (Molloy, 2024). The effect on mortality within one year remained uncertain (Molloy, 2024).

Does home-based rehabilitation work?

In low- to moderate-risk patients, the improvement in exercise capacity was similar to that of the in-person program (Thomas, 2019). Higher-risk patients were left out of most studies (Thomas, 2019).

What else increases referral?

Automatic referral in the medical record, preferably together with a conversation with the patient before discharge (Gravely-Witte, 2010).

Does rehabilitation replace medications?

It adds to the treatment. Rehabilitation is part of the full treatment of coronary artery disease, alongside medications and control of risk factors (Dibben, 2023).

Why do women take part less?

They are referred and enroll less often, and they face barriers such as comorbidities, lack of social support and family responsibilities (Supervía, 2017).

Is rehabilitation safe?

In the atrial fibrillation studies, serious adverse events showed no clear difference between rehabilitation and control (Buckley, 2024). In home-based rehabilitation, safety appeared similar to that of the in-person program in low- to moderate-risk patients (Thomas, 2019).

Do people with atrial fibrillation benefit?

Probably yes for symptoms and arrhythmia recurrence, with a relative risk of 0.70 for recurrence (Buckley, 2024). The effect on mortality remained uncertain (Buckley, 2024).

Take-home messages

• Cardiac rehabilitation combines exercise, diet, risk factors and psychosocial support.
• In coronary artery disease, it reduces cardiovascular death, heart attack and hospitalization, with little change in all-cause mortality.
• In heart failure, it reduces hospitalizations and improves quality of life.
• Valve disease and atrial fibrillation have less and more uncertain evidence.
• The main bottleneck is the referral that does not happen.
• Automatic referral plus a conversation before discharge is the most effective combination.
• Women, minorities and rural residents need active attention.
• Home-based rehabilitation is an alternative for low- to moderate-risk patients.

Play today's case on NEXO.

References

1. Dibben G, Faulkner J, Oldridge N, et al. Exercise-based cardiac rehabilitation for coronary heart disease. Cochrane Database Syst Rev. 2021. PMID 34741536. DOI 10.1002/14651858.CD001800.pub4.
2. Dibben GO, Faulkner J, Oldridge N, et al. Exercise-based cardiac rehabilitation for coronary heart disease: a meta-analysis. Eur Heart J. 2023. PMID 36746187. DOI 10.1093/eurheartj/ehac747.
3. Molloy C, Long L, Mordi IR, et al. Exercise-based cardiac rehabilitation for adults with heart failure. Cochrane Database Syst Rev. 2024. PMID 38451843. DOI 10.1002/14651858.CD003331.pub6.
4. Thomas RJ, Beatty AL, Beckie TM, et al. Home-Based Cardiac Rehabilitation: A Scientific Statement From the American Association of Cardiovascular and Pulmonary Rehabilitation, the American Heart Association, and the American College of Cardiology. J Am Coll Cardiol. 2019. PMID 31097258. DOI 10.1016/j.jacc.2019.03.008.
5. Gravely-Witte S, Leung YW, Nariani R, et al. Effects of cardiac rehabilitation referral strategies on referral and enrollment rates. Nat Rev Cardiol. 2010. PMID 19997077. DOI 10.1038/nrcardio.2009.223.
6. Supervía M, Medina-Inojosa JR, Yeung C, et al. Cardiac Rehabilitation for Women: A Systematic Review of Barriers and Solutions. Mayo Clin Proc. 2017. PMID 28365100. DOI 10.1016/j.mayocp.2017.01.002.
7. Mathews L, Brewer LC. A Review of Disparities in Cardiac Rehabilitation: Evidence, Drivers, and Solutions. J Cardiopulm Rehabil Prev. 2021. PMID 34727556. DOI 10.1097/HCR.0000000000000659.
8. Abraham LN, Sibilitz KL, Berg SK, et al. Exercise-based cardiac rehabilitation for adults after heart valve surgery. Cochrane Database Syst Rev. 2021. PMID 33962483. DOI 10.1002/14651858.CD010876.pub3.
9. Buckley BJ, Long L, Risom SS, et al. Exercise-based cardiac rehabilitation for adults with atrial fibrillation. Cochrane Database Syst Rev. 2024. PMID 39287086. DOI 10.1002/14651858.CD011197.pub3.
10. Dunlay SM, Witt BJ, Allison TG, et al. Barriers to participation in cardiac rehabilitation. Am Heart J. 2009. PMID 19853708. DOI 10.1016/j.ahj.2009.08.010.