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CHF/ Background

Briefly, chronic/ congestive heart failure causes blood to move through the heart and body at a slower rate. As a result, the pressure within the heart increases and the chambers overtime may compensate with anatomical and pathological changes in attempt to adequately supply the heart and body with oxygen and nutrients. There are two main classifications; diastolic CHF and systolic CHF. Systolic HF causes stretching of the heart chambers over tim
e decreasing the hearts ability to pump blood and diastolic HF which causes thickening/ stiffening of the muscular walls of the chambers resulting in the hearts inability to fill. The Signs/symptoms of heart failure include congested lungs, shortness of breath, dizziness, confusion, fatigue, dry hacking cough or wheezing, fluid retention, and rapid or irregular heartbeat. Chronic heart failure can be caused by CAD, MI, cardiomyopathy, and conditions which can chronically overwork the heart such as uncontrolled hypertension, valve disease, thyroid disease, kidney disease, diabetes, or heart defects present at birth.

chf-picture

https://g.co/kgs/pJVVJ8

What’s the difference between cardiac rehabilitation and “usual care” that CHF patient’s may receive?

  • Cardiac rehab is a medically supervised program that includes formal exercise training, education on heart-healthy living and lifestyle (such as pharmacological education and nutrition), and often counseling to reduce stress.
  • Usual care does NOT incorporate formal exercise training upon discharge. It mainly focuses on education on heart-healthy living and lifestyle, and counseling to reduce stress and discharge upon symptom stabilization.

Clinical Scenario/ PICO

  • The patient is a 56-year-old male presenting with a three-year history of left ventricular CHF NYHA (New York Heart Association) class 2 now newly classified as a NYHA class 3 with potential right ventricular involvement. Upon admission to the hospital, the patient weighed 236 pounds with a BMI of 34.9. His wife drove him to the hospital this morning (9/2/2016) due to complaints of moderate chest pain, perceived heart palpitations, breathlessness, fatigue, sweating, and dizziness upon awakening. The patient had a history of uncontrolled hypertension prior to CHF diagnosis. Upon auscultation, there is slight crackles at the base of his lungs
  • I included the outcome measure of relative VO2max into my search since literature suggests that it is a strong prognostic indicator in chronic heart failure associated with a lower risk of all-cause mortality or all-cause hospitalization. The determinants of VO2max include central (heart rate, stroke volume, cardiac output) and peripheral (muscle oxygen extraction) components. Each of these factors responds favorably to exercise training.
  • PICO: Is cardiac rehabilitation training effective vs. control in prevention of all-cause mortality and hospitalizations with improvement of VO2max for patients with chronic/congestive heart failure?

Search strategy

I searched PubMed, Pedro and CINAHL and found a total of 204 articless. I ruled out articles based on irrelevance to my PICO question, compounding treatments, lack of control groups, and of course those that did not fit my inclusion criteria listed here resulting in a total of 5 articles.

Inclusion criteria: Chronic heart failure, Average Ejection Fraction ≤ 40%, Age ≥ 40 years’ old, Class ≥ II NYHA CHF, clinical signs and symptoms of heart failure, at least one exercise intervention prescription, control group: usual care without formal exercise plan, assessment of at least one of the following outcome measures (Re-hospitalization, All-cause mortality, VO2 MAX, Exercise capacity).

Results:

  • Hospitalization: 3/5 studies assessed hospitalization and all found between-group statistical significance between intervention and control groups
  • Mortality Rate: 3/5 studies assessed mortality rate and all found between-group statistical significance between intervention and control groups
  • VO2: 5/5 studies looked at VO2 and found between-group statistical significance in VO2max between intervention and control groups

Clinical Bottom line

  • There is consistent, high-level evidence that exercise therapy demonstrates improvement in all-cause mortality, hospitalizations, and/or VO2 across RCTs in patients with CHF NYHA class II-IV in comparison to those receiving “usual care.”
  • Formal exercise programs are often not prescribed to CHF patients by health care professionals due to fear of hard-events such as hospitalization and death; however, the evidence presented in the literature indicates the exact opposite.

Limitations

As for limitations, more research needs to focus on the intensity, frequency and duration of exercise therapy. More research needs to include patients with comorbidities since they tend to accumulate in this population and also to further assess the risk benefit ratio of formal exercise with CHF and multiple comorbidities.

Application to case

  • A greater emphasis on formal exercise training to improve clinical outcomes in patients with CHF NYHA class 2-4 upon discharge needs to be established ubiquitously. Specifically, the study Belardinelli demonstrated short/ long-term improvements in VO2max as well as prevention of all-cause mortality and hospitalizations with supervised, (cardiologist & exercise therapist) moderate aerobic training at 60-70% VO2max twice weekly for 10 years. Supervision leads to good adherence and ensures exercise intensity and duration for the levels prescribed. A Coronary Club may represent an efficient model for long-term cardiac rehabilitation programs.
  • We want to avoid the vicious cycle that can occur with CHF patients. When patients are discharged from the hospital to home they are often NOT prescribed a formal exercise program. The problem with this model is that it promotes a sedentary lifestyle in patient’s already at risk for depression and comorbidities. This can lead to further loss of functional independence and therefore exacerbation of CHF and adverse outcomes, recycling them back into the hospital. We as physical therapists and experts in movement can be the advocates for these patients to get them into a supervised exercise program to reduce the risk of hospitalizations and all-cause mortality by improving their functional capacity.

References:

Belardinelli R, Georgiou D, Cianci G, Purcaro A. 10-year exercise training in chronic heart failure: A randomized controlled trial. J Am Coll Cardiol. 2012;60(16):1521-1528. https://www.ncbi.nlm.nih.gov/pubmed/22999730

Ahmad T, Fiuzat M, Mark DB, et al. The effects of exercise on cardiovascular biomarkers in patients with chronic heart failure. Am Heart J. 2014;167(2):193-202.e1. https://www.ncbi.nlm.nih.gov/pubmed/24439980

Maria Sarullo F, Gristina T, Brusca I, et al. Effect of physical training on exercise capacity, gas exchange and N-terminal pro-brain natriuretic peptide levels in patients with chronic heart failure. Eur J Cardiovasc Prev Rehabil. 2006;13(5):812-817.            https://www.ncbi.nlm.nih.gov/pubmed/term=Effect+of+physical+training+on+exercise+capacity,+gas+exchange+%09and+N-terminal+pro-brain+natriuretic+peptide+levels+in+patients+with+chronic+heart+failure

Swank AM, Horton J, Fleg JL, et al. Modest increase in peak VO2 is related to better clinical outcomes in chronic heart failure patients: Results from heart failure and a controlled trial to investigate outcomes of exercise training. Circ Heart Fail. 2012;5(5):579-585.            https://www.ncbi.nlm.nih.gov/pubmed/term=Modest+increase+in+peak+VO2+is+related+to+better+clinical+outcomes+in+%09chronic+heart+failure+patients

Erbs S, Höllriegel R, Linke A, et al. Exercise training in patients with advanced chronic heart failure (NYHA IIIb) promotes restoration of peripheral vasomotor function, induction of endogenous regeneration, and improvement of left ventricular function. Circ Heart Fail. 2010;3(4):486-494. https://www.ncbi.nlm.nih.gov/pubmed/term=Exercise+training+in+patients+with+advanced+chronic+heart+failure+%09(NYHA+IIIb)+promotes+restoration+of+peripheral+vasomotor+function%2C+induction+of+endogenous+%09regeneration%2C+and+improvement+of+left+ventricular+function.