February is American Heart Month: an opportunity to raise awareness about heart disease and how to best prevent and control it. According to the Centers for Disease Control and Prevention (CDC), heart disease is one of the largest epidemics in the United States:

• “About 610,000 people die of heart disease in the United States every year–that’s 1 in every 4 deaths.
• Heart disease is the leading cause of death for both men and women. More than half of the deaths due to heart disease in 2009 were in men.
• Coronary heart disease is the most common type of heart disease, killing over 370,000 people annually.
• • Every year about 735,000 Americans have a heart attack. Of these, 525,000 are a first heart attack and 210,000 happen in people who have already had a heart attack.” 1

The leading treatment of heart disease is open-heart surgery, and coronary artery bypass grafting is the most common type of open-heart surgery in the United States.2 As a physical therapist, you may see these patients after their procedures to help them return to function, but also establish a healthier lifestyle to avoid further complications with heart disease. But is exercise a safe option for patients who have undergone coronary artery bypass grafting? Let’s explore the research.

Not only is exercise a critical component of cardiac rehabilitation, but it is one of the largest preventative factors to combat heart disease from ever showing up.

“Approximately 80% of coronary artery disease (CAD)-related deaths are attributable to modifiable behaviors, such as a lack of physical exercise training. Regular exercise training decreases CAD morbidity and mortality through systemic and cardiac-specific adaptations:

• Increases myocardial oxygen demand acting as a stimulus to increase coronary blood flow and thus myocardial oxygen supply, which reduces myocardial infarction and angina.
• Augments coronary blood flow through direct actions on the vasculature that improve endothelial and coronary smooth muscle function, enhancing coronary vasodilation.
• Promotes collateralization, thereby, increasing blood flow to ischemic myocardium and also treats macrovascular CAD by attenuating the progression of coronary atherosclerosis and restenosis, potentially through stabilization of atherosclerotic lesions.” 3

However, there are a few precautions you must consider while building your rehabilitation programs.

However, as a physical therapist, it is important that you work with your patient’s surgeon to make sure you’re addressing the appropriate sternal precautions for at least four to six weeks post-op. For example, immediately after the procedure, the doctor may not want the patient to:

• Lift more than 5 pounds
• Push or pull with the arms
• Reach behind the back
• Reach overhead 4

Different patients may have different precautions, so communication between yourself and the surgeon is critical to patient safety.

Immediately post-op, you may perform mobilization, range of motion exercises and breathing exercises with your patients.5 Progressive aerobic exercise is also critical, both in the hospital and as a prescribed method of rehabilitative exercise upon discharge.

“As a general rule, engage in aerobic exercises that work the large musculature of the lower body (i.e., hips/legs), are rhythmic in nature (i.e., walking and cycling) and can be performed over an extended period of time (i.e., 20+ minutes). Begin with multiple (6-8) short duration exercise bouts of about 3-5 minutes each per day. Then gradually work up to progressively longer duration bouts fewer times per day. Aim to progress to 40-60 minutes non-stop at a comfortable pace as you advance through the recovery phase.”6

While aerobic fitness sets the foundation for a healthy recovery, physical therapists must also consider the prescription of resistance exercise into post-open-heart surgery rehabilitation protocol. Experts believe that resistance exercises can be used alongside aerobic exercise to “decrease recurrent cardiac events, increase survival, physical and psychosocial independence and improve quality of life.” 6

To prove the benefits of resistance exercise within the open-heart surgery patient population, one study evaluated the effects of resistance exercise applied early after coronary artery bypass grafting on functional capacity and pulmonary function.7

Hospitalized study participants were split into two groups: a control group performed diaphragmatic breathing exercises, progressive ambulation and assisted and active exercises for the upper and lower limbs, while an intervention group performed diaphragmatic breathing exercises, progressive ambulation and resistance exercises for the upper and lower limbs.

“Resistance exercises consisted of muscle training with dumbbells for upper limbs (biceps and triceps) and shin pads for lower limbs (quadriceps) with the patient in Fowler 45, during immediate postoperative period, and subsequently sitting in bed with free lower limbs allowing alternated and unilateral knee extension. Training of hip adductors and abductors and triceps surae occurred at ward, where patient was free to ambulate, and consisted of three sets of ten repetitions for each muscle group.”7

Key findings from this study included:

• Intubation time, length of stay in ICU and hospital were not significantly different between the groups.
• Both groups experienced a significant decrease in forced vital capacity, forced expiratory volume in the first second and peak expiratory flow at hospital discharge compared with preoperative values.
• Control group subjects showed a significant decrease in the predicted distance on a six-minute walk test, while the intervention group maintained the predicted distance.
• Resistance exercise exerted no effect on pulmonary function of intervention group compared to control group.7

The authors concluded that “resistance exercise, applied early, may promote maintenance of functional capacity on coronary artery bypass grafting patients, having no impact on pulmonary function when compared to conventional physical therapy.”7

While it might be easy to administer resistance exercises within an in-patient setting, let’s consider some of the implications the different types of resistance exercise might have on rehabilitation success outside of the hospital.

But before you begin prescribing exercises, there are a few final details to consider. First, assess whether elastic or isotonic resistance is the best training option for this patient population; read this article to learn more about the pros and cons of each.

Second, regulating your patient’s Rating of Perceived Exertion (RPE) will help you make sure that you are not overworking the patient’s cardiovascular system or musculoskeletal system while they heal. The RPE scale was originally developed for cardiac rehabilitation, and should be used to both dose and regulate exercise during resistance exercise, as recommended by the American College of Sports Medicine.

Regarding both of these factors, there has been some skepticism around the validity of dosing elastic resistance exercises on the existing RPE scale. However, one study provided a new measurement standard that can be used to more easily assess RPE in patients using elastic resistance. Introducing, the RISE scale.

“Dr. Juan Colado of the University of Valencia in Spain has validated the use of perceived exertion during Thera-Band® resisted exercises using the OMNI-RES (resistance) scale. He has shown that using the scale is an effective method of dosing elastic resistance exercises for significant gains in strength and muscle mass (Colado & Triplett 2008). At the TRAC 2011 meeting, Dr. Colado presented a new scale specific to Thera-Band resistance bands.

20 healthy subjects performed frontal and lateral raises with Thera-Band elastic bands while rating their perceived exertion on the OMNI-RES scale, and then on his new RISE (Resistance Intensity Scale for Exercise) scale – for exertion rating of both the active muscles and the overall body. Using a regression analysis, Dr. Colado demonstrated high validity of the Thera-Band RISE, supporting its use in prescribing and dosing appropriate levels of TheraBand elastic resistance exercises.”8

Read the full abstract of his study here.

While applying these principles can help you better serve your patients with cardiovascular health complications both during and after American Heart Month, becoming a champion of building healthier lifestyles can help reduce the volume of heart disease that is ravaging our nation. Share this article with colleagues on social media, utilize this toolkit from the Office of Disease Prevention and Health Promotion to spread awareness of the cause, and talk to each and every one of your patients about their risk of heart disease. As a healthcare professional, you can make a great impact!

Sources:

1. https://www.cdc.gov/heartdisease/facts.html
2. https://www.nhlbi.nih.gov/health-topics/coronary-artery-bypass-grafting
3. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4366344/
4. https://www.verywellhealth.com/sternal-precautions-2696084
5. https://www.omicsonline.org/physical-therapy-treatment-after-cardiac-surgery-a-national-survey-of-practice-in-greece-2155-9880.S7-004.php?aid=14279
6. https://drbillsukala.com/tips-for-safe-exercise-after-open-heart-surgery/
7. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4762553/
8. http://blog.performancehealthacademy.com/2011/12/15/announcing-the-new-thera-band®-resistance-intensity-scale-for-exercise-rise/