Exercising With Valvular Heart Disease: Prescription for Health
Exercise is an important component in the prevention and rehabilitation of many forms of cardiovascular disease, including valvular heart diseases. It has many beneficial effects including lowering blood pressure, cholesterol and blood sugar, and aiding in weight management. Although exercise does not improve the function of diseased valves, it can improve the efficiency of oxygen extraction by the skeletal muscles and improve work capacity of the individual. The key to maximizing the benefits of exercise is to follow a well-designed program that is safe and sustainable over the long term. In order to give safe and effective exercise recommendations to patients suffering from heart valve disease, the following characteristics are useful to take note of:
1) The valves involved, type of abnormality (stenosis or regurgitation) and etiology
2) Severity of the valvular lesion based on echocardiographic and clinical features
3) Presence of adverse secondary features such as left ventricular systolic dysfunction, chamber dilatation, exercise induced pulmonary hypertension on echo, or exercise induced hypotension or syncope
4) Evidence of concurrent significant arrhythmias
5) Presence of symptoms, in particular dyspnea, syncope, palpations or angina
A careful history and physical examination can elicit the presence of signs and symptoms suggesting the type and severity of the valvular lesion. Sometimes significant lesions may not be apparent on clinical history and examination alone. A transthoracic echocardiogram then becomes particularly useful in the evaluation. In addition functional stress testing can also be used to assess the significance of valvular lesions when the patient’s symptoms are out of proportion to the severity of the lesion based on resting echocardiogram findings. During treadmill or supine bicycle stress echocardiography, deterioration of the valve function may be demonstrated, signifying more severe disease than originally believed.
Principles of exercise recommendation in valvular heart disease
Any patient with suspected valvular heart disease with symptoms or evidence of arrhythmias should be thoroughly evaluated before embarking on exercise. However if the patient has asymptomatic valvular heart disease, physical activity should be encouraged for its multiple health benefits. In general if the condition is mild and there are no accompanying adverse secondary features, then there are no restrictions to exercise of any intensity or participation in competitive sports.
For moderate regurgitant lesions, light to moderate intensity activities are generally allowed. In contrast moderate valvular stenosis should be limited to only light intensity. If more vigorous activity is desired, an exercise stress test may be advisable to assess the suitability and safety. Once any valvular disorder becomes severe, or if there are any adverse secondary features present, vigorous activity or competitive sports are restricted. They should limit themselves to only light activities. If more vigorous exercise is desired, they should be carefully assessed by a cardiologist, and exercise testing carried out with caution. Strength training is also generally not recommended in valvular stenosis.
Most valve abnormalities can be corrected with surgical or percutaneous procedures. Following surgery, patients are also encouraged to begin an exercise program to improve exercise tolerance and prevent other heart problems. Patients with bioprosthetic or mechanical valves should limit themselves to moderate or lower intensity exercise training. Patients on anticoagulation therapy (warfarin) for mechanical valves or atrial fibrillation should avoid contact sports. When in doubt, always start at low intensity and shorter durations, choosing lower impact activities such as walking, cycling or water exercises. Stress testing can always be done to determine a safe level of intensity and formulate an exercise prescription in order to keep individuals active and maximize their functional ability. Serial evaluation is required as valve status may change with time, necessitating matching changes in the exercise recommendations.
Sources: ACSM’s Guidelines for Exercise Testing and Prescription; 36th Bethesda Conference, Task force 3: Valvular Heart Disease.