Intensive Cardiac Rehabilitation: an Underutilized Resource

Online Intensive Cardiac Rehabilitation Program for Japanese Patients With Coronary Artery Disease - A Pilot Study Protocol

Background

A comprehensive cardiac rehabilitation (CR) program is recommended for coronary artery disease (CAD). However, many facilities do not have established programs for dietary guidance and patient education, resulting in an exercise-based CR program and limited efficacy for secondary prevention.

Methods and Results

A pilot study will be conducted to develop an online Japanese-style intensive cardiac rehabilitation (J-ICR) program for Japanese patients with CAD and will examine adherence, safety, and efficacy. Twenty-four patients diagnosed with stable CAD will be randomly assigned in a 1 : 1 ratio to either an early or late-phase group. The program will comprise the following four parts: exercise sessions; dietary education centered on "the Japan diet"; mindfulness; and group support, with a frequency of 3 h per session, once a week for 12 weeks (a total of 36 h). The primary endpoint will be program feasibility, determined by examining its adherence. Physical examination and function, stress-coping skills, risk of classic CAD (e.g., lipid profile, glucose tolerance, and blood pressure), and dietary changes will be assessed as secondary endpoints.

Conclusions

The online J-ICR program is designed as a comprehensive CR program for Japanese patients with CAD. If this program shows high adherence and an improvement in CAD risk factors, its secondary prevention effect should be verified with appropriately powered randomized trials at multiple centers.

Cardiac rehabilitation for heart failure: progress and gaps in evidence and policy

PURPOSE OF REVIEW

This review synthesizes recent research on the efficacy, optimal design, and delivery methods of cardiac rehabilitation tailored to heart failure patients. Despite established benefits, cardiac rehabilitation referral and access disparities persist, necessitating elucidation of limitations and solutions.

RECENT FINDINGS

Exercise-based cardiac rehabilitation improves long-term mortality and hospitalization rates but not short-term mortality. cardiac rehabilitation further enhances quality of life and medical therapy adherence. However, cardiac rehabilitation relies on in-person delivery, presenting access barriers exacerbated during COVID-19. Significant geographic disparities exist, with analyses indicating current capacity only serves 45% of eligible US adults even if fully utilized. Referral rates also lag, disproportionately affecting women and minority groups. Research increasingly focuses on home-based and digital therapeutics modalities to expand reach, with evidence demonstrating comparable improvements across settings. Protocols and research center on heart failure with reduced ejection fraction (HFrEF), despite growing heart failure with preserved ejection fraction (HFpEF) prevalence.

SUMMARY

Increasing referrals through standardized procedures and addressing multifactorial geographic, economic, and capacity limitations are imperative to ensure equitable cardiac rehabilitation access. Broadening HFpEF rehabilitation research and care standards also constitutes a critical practice gap requiring alignment with projected epidemiologic shifts. Advancing patient-centered, evidence-based solutions can promote rehabilitation as essential secondary prevention for wider cardiac populations.

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Differential associations of sex and age with changes in HRQoL during outpatient cardiac rehabilitation

INTRODUCTION

Cardiovascular diseases (CVD) represent the world's leading cause of death. Health-related quality of life (HRQoL) is a widely applied concept of patients' perceived health and is directly linked to CVD morbidity, mortality, and re-hospitalization rates. Cardiac rehabilitation (CR) improves both cardiovascular outcomes and HRQoL. Regrettably, CR is still underutilized, especially in subgroups like women and elderly patients. The aim of our study was to investigate the predictive potential of sex and age on change of HRQoL throughout outpatient CR.

METHODS

497 patients of outpatient CR were retrospectively assessed from August 2015 to September 2019 at the University Hospital Zurich. A final sample of 153 individuals with full HRQoL data both at CR entry and discharge was analyzed. HRQoL was measured using the 36-Item Short Form Survey (SF-36) with its physical (PCS) and mental (MCS) component scale. In two-factorial analyses of variance, we analyzed sex- and age-specific changes in HRQoL scores throughout CR, adjusting for psychosocial and clinical characteristics. Age was grouped into participants over and under the age of 65.

RESULTS

In both sexes, mean scores of physical HRQoL improved significantly during CR (p <.001), while mean scores of mental HRQoL improved significantly in men only (p =.003). Women under the age of 65 had significantly greater physical HRQoL improvements throughout CR, compared with men under 65 (p =.043) and women over 65 years of age (p =.014). Sex and age did not predict changes in mental HRQoL throughout CR.

CONCLUSIONS

Younger women in particular benefit from CR with regard to their physical HRQoL. Among older participants, women report equal improvements of physical HRQoL than men. Our results indicate that sex- and age-related aspects of HRQoL outcomes should be considered in CR.

Intensive Versus Traditional Cardiac Rehabilitation: Mortality and Cardiovascular Outcomes in a 2016-2020 Retrospective Medicare Cohort

BACKGROUND

Traditional cardiac rehabilitation (CR) improves cardiovascular outcomes and reduces mortality, but less is known about the relative benefit of intensive CR (ICR) which incorporates greater lifestyle education through 72 sessions (versus 36 in CR). Our objective was to determine whether ICR is associated with a mortality and cardiovascular benefit compared with CR.

METHODS

Retrospective cohort study of Medicare Fee-For-Service beneficiaries in a 100% sample, claims data set. Qualifying events were captured from May 1, 2016 to December 31, 2019 and ICR/CR utilization captured from May 1, 2016 to December 31, 2020. Among patients attending at least 1 day of either CR or ICR, Cox proportional hazards models using a 1 to 5 propensity score match were used to compare utilization and the association of ICR versus CR participation with (1) all-cause mortality and (2) cardiovascular-related hospitalizations or nonfatal cardiac events. Dose-response was assessed by the number of days attended.

RESULTS

From 2016 to 2019, 1 277 358 unique patients met at least one qualifying indication for ICR/CR from 2016 to 2019. Of these, 262 579 (20.6%) and 4452 (0.4%) attended at least one session of CR or ICR, respectively (mean [SD] age, 73.2 [7.8] years; 32.3% female). In the matched sample, including 26 659 total patients (median, 2.4-year follow-up), ICR was associated with 12% lower all-cause mortality (multivariable adjusted hazard ratio, 0.88 [95% CI, 0.78-0.99]; P=0.036) compared with CR but no significant difference for cardiovascular-related hospitalization or nonfatal cardiac events. The mortality benefit was seen for both ICR and CR per day strata, with each modality demonstrating a clear dose-response benefit.

CONCLUSIONS

ICR is associated with lower mortality than traditional CR among Medicare beneficiaries but no difference in cardiovascular-related hospitalization or nonfatal cardiac events. Moreover, ICR and CR demonstrate a dose-response relationship for mortality. Additional studies are needed to confirm these observations and to better understand the mechanisms by which ICR may lead to a reduction in mortality.

Educational Attainment and Cardiovascular Risk Among Patients in Cardiac Rehabilitation

We explored whether patient educational attainment impacted changes in cardiovascular risk factors during cardiac rehabilitation (CR). An observational study was conducted using participant data who completed phase 2 of CR from January 2011 to February 2020 at an academic medical center. The patient cohort was referred to CR after a major cardiac event or to outpatients with stable angina. Patients were excluded if they had no recorded food frequency assessment (FFA) score at CR orientation and graduation. The eligible sample of 1,307 patients were further divided: (1) low educational attainment group (<16 years formal education: high school, high school/general educational development, trade school, and associate's degree) and (2) high educational attainment group (>16 years formal education: bachelor's degree, some postgraduate, master's degree, PhD, and MD). The outcomes included measurements of the FFA, body composition, biophysical health, and psychologic distress. Most patients were male (71.2%), non-Hispanic White (82.2%), and married (73.0%). There were more patients with a high educational attainment (56.8%) than patients with a low educational attainment (43.2%). All measured cardiovascular markers improved after CR for both education level groups. The change in mean FFA score (0.163, p = 0.11) and Brief Symptom Inventory-53 global severity index score (0.422, p = 0.34) did not differ significantly. We observed an improvement in cardiovascular risk measures upon CR participation. These improvements were not limited to high educational attainment patients because we found few differences in the change of risk between the 2 groups. Future studies should continue investigating the impact of education on cardiovascular outcomes as an important social determinant of health.

The impact of obstructive sleep apnea on exercise capacity in a cardiac rehabilitation program

PURPOSE

Cardiac rehabilitation (CR) improves clinical outcomes in patients with cardiovascular disease (CDV). Patients with CVD often have multiple comorbidities, including obstructive sleep apnea (OSA), potentially affecting their ability to participate and achieve functional improvement during CR. We aimed to test the hypothesis that OSA reduces peak exercise capacity (EC) in patients undergoing CR and to explore if OSA treatment modifies this relationship.

METHODS

Data from a retrospective cohort of CR patients was analyzed. OSA was defined as a respiratory event index > 5/h or physician diagnosis. Patients with OSA were considered "treated" if using continuous positive airway pressure regularly during the CR period. Change in METs was the primary study outcome.

RESULTS

Among 312 CR patients, median age of 67 years, 103 (33%) had known OSA (30 treated, 73 untreated). Patients with OSA vs. those with no OSA were more likely to be obese and male; otherwise, groups were similar. Compared with the no OSA group, patients with OSA had lower pre-CR METs (3.3 [2.9-4.5] vs. 3.9 [3.1-5], P = .01) and lower post-CR METs (5.3 [4-7] vs. 6 [4.6-7.6], P = .04), but achieved a similar increase in METs post-CR (1.8 [0.6-2.6] vs. 2.0 [0.9-3], P = .22). Furthermore, compared to no OSA, pre-CR and post-CR METs tended to be similar in patients with treated OSA, but lower in untreated patients, with similar increases in METs across all groups, even when adjusting for covariates via multivariable regression.

CONCLUSION

OSA is prevalent in patients with CVD undergoing CR. CR substantially improves exercise capacity independent of OSA status, but screening for-and treatment of-OSA may improve the absolute exercise capacity achieved through CR.

The Impact of Underlying Obstructive Sleep Apnea Treatment on Exercise Capacity in Patients With Pulmonary Hypertension Undergoing a Cardiac Rehabilitation Program

PURPOSE

Obstructive sleep apnea (OSA)-related pulmonary hypertension (PH) can often be reversed with treatment of OSA via continuous positive airway pressure. We hypothesized that treatment of OSA would be associated with a greater improvement in exercise capacity (EC) with cardiac rehabilitation (CR), especially in patients with PH as compared with those who are untreated.

METHODS

We reviewed medical records of 315 consecutive patients who participated in CR. Pulmonary hypertension status was assessed on the basis of peak tricuspid regurgitant velocity (>2.8 m/sec) on pre-CR echocardiograms. The OSA status (no, untreated, or treated OSA) was determined on the basis of results from sleep studies, continuous positive airway pressure device data, and physician notes. Exercise capacity was assessed by measuring metabolic equivalents (METs) using a treadmill stress test before and after CR.

RESULTS

We included 290 patients who participated in CR with available echocardiographic data: 44 (15%) had PH, and 102 (35%) had known OSA (30 treated and 72 untreated). Patients with OSA versus those with no OSA were more likely to have PH ( P = .06). Patients with PH versus no-PH were associated with significantly lower baseline METs in crude and adjusted analyses ( P ≤. 004). The PH and OSA status in isolation were not associated with changes in METs ( P > .2) with CR. There was a significant interaction between OSA treatment and PH in crude and adjusted analyses ( P ≤.01): treatment vs no treatment of OSA was associated with a clinically and statistically greater improvement in METs in patients who participated in CR with but not without PH.

CONCLUSION

Baseline PH was associated with decreased baseline EC but did not attenuate CR-related improvements in METs. However, in the subset of OSA patients with PH, OSA therapy was associated with improved EC after CR.

Intensive Cardiac Rehabilitation Attenuates the Gender Gap in Cardiac Rehabilitation Participation

INTRODUCTION

Traditional cardiac rehabilitation programs historically have had considerable gender gaps in cardiac rehabilitation (CR) outcomes. Intensive-Cardiac-Rehabilitation (ICR) has non-exercise components such as stress management, peer support and diet modification, in addition to exercise, which may reduce barriers to CR completion. However, there is a paucity of data in ICR outcomes based on gender.

METHODS

We conducted a nationwide retrospective cohort study of 15,613 patients enrolled in 46 Ornish-ICR programs across the US from January 2016 - December 2020 and compared ICR physical and psychological outcomes in women versus men. Primary endpoints were depression scores (CESD), health status (SF-36 physical and mental composite-scores) and exercise minutes per week.

RESULTS

Of 15,613 ICR participants who participated in the program, 6788 (44%) were women. ICR completion rates were 64.7% overall and nearly equal between men and women (63.3% women vs 65.9% men). There were a few small differences in outcomes after ICR completion: women had slightly more improvement in depression scores (women: -6.10 ± 8.79, 49.6% reduction vs. men: -4.92 ± 7.80, 46.4% reduction; P<0.01) and SF-36 physical (women: 5.95±6.86 vs men: 5.28±6.71, P<0.01) and SF-36 mental (women: 5.76±8.11 vs men: 4.60±7.33, P<0.01) composite scores than men. There was no significant difference in exercise-minutes per week between the two groups.

CONCLUSIONS

ICR attenuates the gender gap in cardiac rehabilitation completion. Further, of the completers, women achieved slightly higher depression and quality-of-life improvements compared to men. As such, ICR can be a good option to reduce gender-based differences in CR participation.

Physical and Psychological Outcomes of Patients Undergoing Traditional Cardiac Rehabilitation and Intensive Cardiac Rehabilitation

PURPOSE

Both traditional cardiac rehabilitation (TCR) and intensive cardiac rehabilitation (ICR) have proven benefits for patients with cardiovascular disease. The aim of this study was to compare ICR versus TCR on cardiac rehabilitation (CR) outcomes in patients with cardiovascular disease.

METHODS

In a retrospective cohort study of 970 patients (n = 251, ICR; n = 719, TCR) who were referred for CR between January 2018 and December 2019, 693 (71.4%) patients completed it. The TCR sessions were 90 min (60-min exercise) three times/wk for 12 wk, while ICR sessions were 4 hr (60-min exercise) two times/wk for 9 wk. Primary endpoints were change in cardiorespiratory fitness (CRF) (by difference in exercise prescription metabolic equivalents [METs] between the last session and the average of the second and third sessions), anxiety (Generalized Anxiety Disorder-7) scores, percent depression (Patient Health Questionnaire-9 or Center for Epidemiologic Studies Depression Scale) scores, and health status (36-item Short Form Health Survey physical and mental composite scores). Linear regression adjusted for imbalanced baseline characteristics (age, race, and diagnosis of angina).

RESULTS

Of the 693 patients who completed CR (ICR = 204/251 [81%] vs TCR = 489/719 [68%], P < .01), mean age was 66 yr and 31% were female. Patients in TCR had a higher improvement in CRF (CR session METs: ICR +1.5 ± 1.2 vs TCR +1.9 ± 1.5, P < .01) but no difference in health status scores. Conversely, patients in ICR had more reduction in anxiety scores (-2 ± 4 vs -1 ± 3, P < .01) and percent reduction in depression scores (-8.3 ± 13.7% vs -5.0 ± 11.7%, P < .01) than patients in TCR.

CONCLUSIONS

Patients in TCR had higher improvement in CRF while patients in ICR had higher improvement in anxiety and depression scores.

Disparities in Geographic Access to Cardiac Rehabilitation in Los Angeles County

Background Exercise-based cardiac rehabilitation (CR) is known to reduce morbidity and mortality for patients with cardiac conditions. Sociodemographic disparities in accessing CR persist and could be related to the distance between where patients live and where CR facilities are located. Our objective is to determine the association between sociodemographic characteristics and geographic proximity to CR facilities. Methods and Results We identified actively operating CR facilities across Los Angeles County and used multivariable Poisson regression to examine the association between sociodemographic characteristics of residential proximity to the nearest CR facility. We also calculated the proportion of residents per area lacking geographic proximity to CR facilities across sociodemographic characteristics, from which we calculated prevalence ratios. We found that racial and ethnic minorities, compared with non-Hispanic White individuals, more frequently live ≥5 miles from a CR facility. The greatest geographic disparity was seen for non-Hispanic Black individuals, with a 2.73 (95% CI, 2.66-2.79) prevalence ratio of living at least 5 miles from a CR facility. Notably, the municipal region with the largest proportion of census tracts comprising mostly non-White residents (those identifying as Hispanic or a race other than White), with median annual household income <$60 000, contained no CR facilities despite ranking among the county's highest in population density. Conclusions Racial, ethnic, and socioeconomic characteristics are significantly associated with lack of geographic proximity to a CR facility. Interventions targeting geographic as well as nongeographic factors may be needed to reduce disparities in access to exercise-based CR programs. Such interventions could increase the potential of CR to benefit patients at high risk for developing adverse cardiovascular outcomes.

Intensive Cardiac Rehabilitation Is Markedly Underutilized by Medicare Beneficiaries: RESULTS FROM A 2012-2016 NATIONAL SAMPLE

PURPOSE

Intensive cardiac rehabilitation (ICR) was developed to enhance traditional cardiac rehabilitation (CR) by adding sessions focused on nutrition, lifestyle behaviors, and stress management. Intensive CR has been Medicare-approved since 2010, yet little is known about national utilization rates of ICR in the Medicare population or characteristics associated with its use.

METHODS

A 5% sample of Medicare claims data from 2012 to 2016 was used to identify beneficiaries with a qualifying indication for ICR/CR and to quantify utilization of ICR or CR within 1 yr of the qualifying diagnosis.

RESULTS

From 2012 to 2015, there were 107 246 patients with a qualifying indication. Overall, only 0.1% of qualifying patients participated in ICR and 16.2% in CR from 2012 to 2016, though utilization rates of both ICR and CR increased during this period (ICR 0.06 to 0.17%, CR 14.3 to 18.2%). The number of ICR centers increased from 15 to 50 over the same period. There were no differences between ICR and CR enrollees with respect to age, sex, race, discharge location, median income, dual enrollment, or number of comorbidities. Compared with eligible beneficiaries who did not attend ICR or CR, those who attended either program were younger, more likely to be male and White, and had higher median income.

CONCLUSIONS

Although ICR and CR have a class 1 indication for the treatment of cardiovascular disease and the number of ICR centers has increased, ICR is not widely available and remains markedly underutilized. Continued research is needed to understand the barriers to program development and patient participation.

Lifestyle Medicine Reimbursement: A Proposal for Policy Priorities Informed by a Cross-Sectional Survey of Lifestyle Medicine Practitioners

Lifestyle medicine (LM) is a rapidly emerging clinical discipline that focuses on intensive therapeutic lifestyle changes to treat chronic disease, often producing dramatic health benefits. In spite of these well-documented benefits of LM approaches to provide evidence-based care that follows current clinical guidelines, LM practitioners have found reimbursement challenging. The objectives of this paper are to present the results of a cross-sectional survey of LM practitioners regarding lifestyle medicine reimbursement and to propose policy priorities related to the ability of practitioners to implement and achieve reimbursement for these necessary services. Results from a closed, online survey in 2019 were analyzed, with a total of n = 857 included in this analysis. Results were descriptively analyzed. This manuscript articulates policy proposals informed by the survey results. The study sample was 58% female, with median age of 51. A minority of the sample (17%) reported that all their practice was LM, while 56% reported that some of their practice was LM. A total of 55% of practitioners reported not being able to receive reimbursement for LM practice. Of those survey respondents who provided an answer to the question of what would make the practice of LM easier (n = 471), the following suggestions were offered: reimbursement overall (18%), reimbursement for more time spent with patients (17%), more support from leadership (16%), policy measures to incentivize health (13%), education in LM for practitioners (11%), LM-specific billing codes and billing knowledge along with better electronic medical record (EMR) capabilities and streamlined reporting/paperwork (11%), and reimbursement for the extended care team (10%). Proposed policy changes focus on three areas of focus: (1) support for the care process using a LM approach, (2) reimbursement emphasizing outcomes of health, patient experience, and delivering person-centered care, and (3) incentivizing treatment that produces disease remission/reversal. Rectifying reimbursement barriers to lifestyle medicine practice will require a sustained effort from health systems and policy makers. The urgency of this transition towards lifestyle medicine interventions to effectively address the epidemic of chronic diseases in a way that can significantly improve outcomes is being hindered by current reimbursement policies and models.

Effectiveness of Intensive Cardiac Rehabilitation in High-Risk Patients with Cardiovascular Disease in Real-World Practice

Structured lifestyle interventions through cardiac rehabilitation (CR) are critical to improving the outcome of patients with cardiovascular disease (CVD) and cardiometabolic risk factors. CR programs' variability in real-world practice may impact CR effects. This study evaluates intensive CR (ICR) and standard CR (SCR) programs for improving cardiometabolic, psychosocial, and clinical outcomes in high-risk CVD patients undergoing guideline-based therapies. Both programs provided lifestyle counseling and the same supervised exercise component. ICR additionally included a specialized plant-based diet, stress management, and social support. Changes in body weight (BW), low-density lipoprotein cholesterol (LDL-C), and exercise capacity (EC) were primary outcomes. A total of 314 patients (101 ICR and 213 SCR, aged 66 ± 13 years, 75% overweight/obese, 90% coronary artery disease, 29% heart failure, 54% non-optimal LDL-C, 43% depressive symptoms) were included. Adherence to ICR was 96% vs. 68% for SCR. Only ICR resulted in a decrease in BW (3.4%), LDL-C (11.3%), other atherogenic lipids, glycated hemoglobin, and systolic blood pressure. Both ICR and SCR increased EC (52.2% and 48.7%, respectively) and improved adiposity indices, diastolic blood pressure, cholesterol intake, depression, and quality of life, but more for ICR. Within 12.6 ± 4.8 months post-CR, major adverse cardiac events were less likely in the ICR than SCR group (11% vs. 17%), especially heart failure hospitalizations (2% vs. 8%). A comprehensive ICR enhanced by a plant-based diet and psychosocial management is feasible and effective for improving the outcomes in high-risk CVD patients in real-world practice.

Cardiac Rehab in the COVID Era and Beyond: mHealth and Other Novel Opportunities

Purpose of Review

The COVID-19 pandemic has forced many center-based cardiac rehabilitation (CBCR) programs to close or limit their usual offerings. In order for patients to continue to benefit from CR, programs need to rapidly adapt to the current environment. This review highlights ways CR has evolved, and reviews the history of CR and recent advancements in telemedicine including remote patient monitoring, and mobile health that can be applied to CR.

Recent Findings

Despite that initial studies indicate that home-based CR (HBCR) is safe and effective, HBCR has faced several challenges that have prevented it from becoming more widely implemented. Many previous concerns can now be addressed through the use of new innovations in home-based healthcare delivery.

Summary

Since its inception, CR has become increasingly recognized as an important tool to improve patient mortality and quality of life in a broad range of cardiac diseases. While there has been little need to modify the delivery of CR since the 1950s, COVID-19 now serves as the necessary impetus to make HBCR an equal alternative to CBCR.

Unraveling the Role of Respiratory Muscle Metaboloreceptors under Inspiratory Training in Patients with Heart Failure

Exercise intolerance may be considered a hallmark in patients who suffer from heart failure (HF) syndrome. Currently, there is enough scientific evidence regarding functional and structural deterioration of skeletal musculature in these patients. It is worth noting that muscle weakness appears first in the respiratory muscles and then in the musculature of the limbs, which may be considered one of the main causes of exercise intolerance. Functional deterioration and associated atrophy of these respiratory muscles are related to an increased muscle metaboreflex leading to sympathetic–adrenal system hyperactivity and increased pulmonary ventilation. This issue contributes to increased dyspnea and/or fatigue and decreased aerobic function. Consequently, respiratory muscle weakness produces exercise limitations in these patients. In the present review, the key role that respiratory muscle metaboloreceptors play in exercise intolerance is accurately addressed in patients who suffer from HF. In conclusion, currently available scientific evidence seems to affirm that excessive metaboreflex activity of respiratory musculature under HF is the main cause of exercise intolerance and sympathetic–adrenal system hyperactivity. Inspiratory muscle training seems to be a useful personalized medicine intervention to reduce respiratory muscle metaboreflex in order to increase patients’ exercise tolerance under HF condition.

Inspiratory Muscle Training in Patients with Heart Failure

Background: Prior systematic reviews and meta-analysis addressed that inspiratory muscle training (IMT) improved inspiratory muscle weakness, cardiorespiratory fitness and quality of life similar to conventional exercise training as a first alternative in deconditioned patients with heart failure (HF) lead to a better adaptation to posterior exercise training. The heterogeneity and variability in a wide range of new studies about this topic led to the necessity of an updated and comprehensive narrative review. The present review aimed to analyze and update the most relevant studies about IMT in patients who suffer from HF. Methods: A narrative review was carried out about IMT in HF patients including 26 experimental studies divided into 21 clinical trials and 5 quasi-experimental studies identified through database searching in PubMed, Cochrane and PEDro. Results: There is enough evidence to state that IMT produces improvements in functional capacity of patients with HF. Nevertheless, there is not enough evidence to support that IMT could improve cardiovascular parameters, blood biomarkers or quality of life in these patients. Conclusions: Thus, IMT may be recommended to improve functional capacity in patients who suffer from HF; nevertheless, more evidence is needed regarding cardiovascular parameters, biomarkers and quality of life. Furthermore, mortality or HF hospitalization was not evaluated and most studies were not longer than 3 months. According to IMT protocols and study designs heterogeneity and mid-term follow-up, further investigations through high-quality long-term randomized clinical trials should be performed to achieve systematic reviews and meta-analysis to support strong evidence for IMT in HF patients.

Barriers physicians face when referring patients to cardiac rehabilitation: a narrative review

While cardiac rehabilitation (CR) has been shown to be a beneficial form of secondary prevention for patients with cardiovascular disease, barriers of referral to CR still exist for patients. Barriers that specifically make it difficult for physicians to make the referral could be worthwhile to examine. This narrative review hypothesizes that increasing awareness and education on the various aspects of CR as well as simplifying the referral process could lead to increased referral rates as they target physician-related barriers. This narrative review seeks to further understand the physician-related barriers of low CR awareness and hindering referral processes. A search in Scopus was conducted with preference for articles examining CR referral strategies used by physicians; physicians' awareness of CR programs; physicians' perceptions, beliefs, or knowledge of the benefits of CR; or physicians' experience with or understanding of the selection process of CR programs, including indications for referral. Two systematic reviews and two observational studies were selected for discussion. Three of the selected studies had findings supporting the notion that increasing physicians' awareness of CR could impact referral rates. One of the studies evaluated the perceptions that physicians and CR programs had on various referral strategies. While more study is needed to assess the actual level of knowledge and awareness physicians have regarding CR, this review supports using educational interventions as well as targeting various aspects of the referral process for improving referral rates.