Exercise as Treatment

 

     There are various conditions and reasons for a person to enter a cardiac rehabilitation program.  When a patient enters the program, they set goals they plan to achieve.  These goals can cover nutritional habits, weight management, returning to recreational activities, or improving psychological wellness.  Along with these goals, any patients recovering from a cardiac intervention or cardiac event also have the overall goal of improving heart health.

 

Mycardial Infarction and Coronary Artery Disease 

 

     Many people entering the cardiac rehabilitation program have experienced a myocardial infarction (MI), also known as a heart attack.  In most cases, this is the product of plaque buildup in the coronary arteries which causes a blockage and lack of blood flow to an area of the myocardium, resulting in cell death.

     Recent data shows that initiating an aerobic exercise program around 1 week post MI results in the largest changes in left ventricular remodeling.  Essentially, the sooner an individual engages in exercise the less likely they are to experience pathological effects that ensue after they experience damage to the myocardium.  This is a significant finding considering most cardiac rehabilitation programs are not implemented until four to six weeks after hospital discharge. 

      Changes in ejection fraction (EF) effect size difference decreased as time between MI and initiation of exercise program lengthened, and greater reductions in end systolic volume (ESV) and end diastolic volume (EDV) occurred with earlier initiation of exercise.  These are some examples that illustrate not only the importance of exercise for people who have experienced an MI, but also the importance of early initiation of this exercise post-MI.

     In addition to the beneficial effects an aerobic exercise program has on left ventricular remodeling, improvements in functional capacity of individuals who have coronary artery disease or have experienced an MI is another benefit of exercise.  In general, people with coronary artery disease have a decreased maximal oxygen uptake (VO2max) compared to healthy individuals.  Exercise can increase VO2max in those with coronary artery disease by increasing arteriovenous difference, and in some cases stroke volume.  This increase in VO2max can range from 10-60% as reported by the ACSM.

     There are many other benefits that an exercise program can have for people with coronary artery disease or for those recovering from an MI.  Hypertension control, obesity control, decrease in cardiovascular mortality, and even psychological benefit are all benefits of engaging in regular exercise.  

 

Chronic Heart Failure

 

     The prevalence and incidence of chronic heart failure (CHF) is increasing and is also the leading cause of hospitalization in the Medicare age group.  CHF occurs when the heart no longer pumps blood efficiently, and people who are diagnosed with CHF commonly experience diminished functional capacity, impaired quality of life, and disability.  For people who are diagnosed with CHF (at the Class 1or 2 level), exercise training can be beneficial and is supported by the American Heart Association, American College of Cardiology, and Heart Failure Society of America.  By engaging in aerobic exercise training improvements in peak VO2, hemodynamic function, autonomic function, peripheral vascular and muscle function, and exercise capacity can be achieved.

     Looking at a meta-analysis of 57 studies that included patients who had a reduced ejection fraction and that directly measured VO2, an average of 17% improvement in peak VO2 was reported.  There is also data showing 15% lower mortality in CHF patients who participate in cardiac rehabilitation compared to those who do not.

     The implementation of cardiac rehabilitation as therapy for people living with CHF is a new strategy for improving the health for so many people with this condition.  With data to support the various benefits of engaging in exercise in the setting of cardiac rehabilitation it is clear that this type of therapy has the ability to alleviate some of the debilitating effects CHF presents.