(See also Overview of Rehabilitation.)
Rehabilitation may benefit some patients who have coronary artery disease or heart failure or who have had a recent MI or coronary artery bypass surgery, particularly those who could do activities of daily living independently and walk before the event. Cardiac rehabilitation aims to help patients maintain or regain independence (see Overview of Acute Coronary Syndromes (ACS) : Rehabilitation and Postdischarge Treatment).
Typically, rehabilitation begins with light activities and progresses on an individualized basis; ECG monitoring is often used. High-risk patients should exercise only in a well-equipped cardiovascular rehabilitation facility under the supervision of a trained attendant.
When patients are able, they are taken by wheelchair to a physical therapy gym in the hospital. Exercise may involve walking, a treadmill, or a stationary bicycle. When patients tolerate these exercises well, they progress to stair-climbing. If shortness of breath, light-headedness, or chest pain occurs during exercise, the exercise should be stopped immediately, and cardiac status should be reassessed. Before hospital discharge, patients are assessed so that an appropriate postdischarge rehabilitation program or exercise regimen can be recommended.
Physical activity is measured in metabolic equivalents (METs), which are multiples of the resting rate of oxygen consumption; 1 MET (the resting rate) equals about 3.5 mL/kg/min of O2 (see Table: Endurance Exercises and Their Metabolic Requirement). Normal working and living activities (excluding recreational activities) rarely exceed 6 METs. Light to moderate housework is about 2 to 4 METs; heavy housework or yard work is about 5 to 6 METs.
For hospitalized patients, physical activity should be controlled so that heart rate remains < 60% of maximum for that age (eg, about 160 beats/min for people aged 60); for patients recovering at home, heart rate should remain < 70% of maximum.
For patients who have had an uncomplicated MI, a 2-MET exercise test may be done to evaluate responses as soon as patients are stable. A 4- to 5-MET exercise test done before discharge helps guide physical activity at home. Patients who can tolerate a 5-MET exercise test for 6 min can safely do low-intensity activities (eg, light housework) after discharge if they rest sufficiently between each activity.
Unnecessary restriction of activity is detrimental to recovery. The physician and other members of the rehabilitation team should explain which activities can be done and which cannot and should provide psychologic support. When discharged, patients can be given a detailed home activity program. Most elderly patients can be encouraged to resume sexual activity, but they need to stop and rest if necessary to avoid overexertion. Young couples expend 5 to 6 METs during intercourse; whether elderly couples expend more or less is unknown.