Ejection fraction is a measurement, expressed as a percentage, of how much blood the left ventricle of the heart pumps out with each contraction. A normal ejection fraction is typically between 55% and 70%. Cardiac rehabilitation is a medically supervised program designed to improve cardiovascular health after a cardiac event. Research indicates cardiac rehabilitation can improve ejection fraction for many individuals, with one study showing a significant increase after a 12-week program.
The Physiological Impact of Cardiac Rehab on Ejection Fraction
A primary way cardiac rehabilitation improves ejection fraction is by promoting positive “cardiac remodeling.” This refers to changes in the heart’s size, shape, and function. Following a cardiac event like a heart attack, the heart muscle can become weakened and enlarged, leading to a less efficient pumping action. Supervised exercise, a core part of rehab, can help reverse these negative changes.
The structured physical activity in cardiac rehab strengthens the heart muscle. A stronger heart muscle can contract more forcefully, pushing more blood out with each beat and thereby increasing the ejection fraction. This improved efficiency means the heart doesn’t have to work as hard to supply the body with oxygen-rich blood, reducing its overall workload.
Studies have shown that consistent exercise training can lead to small but significant improvements in left ventricular ejection fraction and other measures of heart structure. The benefits appear to be most significant with longer-term training of at least six months.
Core Components of a Cardiac Rehabilitation Program
A comprehensive cardiac rehabilitation program is built on several pillars, with the most recognized being medically supervised exercise. This is a tailored exercise prescription, often including activities like treadmill walking or stationary cycling, designed and monitored by healthcare professionals. The intensity and duration of exercise are gradually increased as the patient’s fitness improves.
Beyond exercise, patient education is an aspect of cardiac rehab. This involves sessions that provide information on managing cardiovascular risk factors. Topics often include nutritional counseling to promote a heart-healthy diet, strategies for quitting smoking, and understanding the purpose and proper use of prescribed medications.
The emotional and psychological recovery from a cardiac event is also addressed through counseling and support. It’s common for individuals to experience stress, anxiety, or depression after a heart attack or diagnosis of heart failure. Cardiac rehab programs provide a supportive environment where patients can share their experiences and learn coping mechanisms.
Broader Cardiovascular Improvements from Cardiac Rehab
While improvements in ejection fraction are a significant goal, cardiac rehabilitation offers a wide range of other cardiovascular benefits. These broader improvements contribute to overall health and can reduce the risk of future cardiac events.
Participation in cardiac rehab often leads to better management of blood pressure and cholesterol levels. The combination of exercise and nutritional guidance helps lower LDL (“bad”) cholesterol and can lead to a reduction in blood pressure, both of which are major risk factors for heart disease. For individuals with diabetes, these programs can also improve blood sugar control.
Another outcome is an increase in overall stamina and exercise capacity. Patients often report feeling less fatigue and shortness of breath during daily activities. This improvement in functional capacity can lead to a better quality of life and a greater ability to engage in work, hobbies, and social activities.
Tracking Improvement and Setting Realistic Expectations
Ejection fraction is most commonly measured using an echocardiogram, an ultrasound of the heart. Other methods include cardiac MRI, CT scans, and nuclear stress tests. After starting cardiac rehabilitation, a follow-up echocardiogram may be performed to assess for any changes in heart function.
It is important for patients to have realistic expectations. While many people see an increase in their ejection fraction, the degree of change varies widely. The goal of cardiac rehab is not solely focused on one number, but on improving overall health, reducing symptoms like fatigue, and lowering the risk of future cardiac events.