Striving for a hearty recovery

By Dr. Sunil Seneviratne Epa

Saman, a businessman suffers a heart attack at the age of 55. Two months later he still finds it an effort to climb the stairs in his shop. He goes back to his doctor for a check-up, but nothing is wrong and he is asked to continue his medication.

Chandana, 43, an executive suffers a heart attack and undergoes bypass surgery immediately. He is sent home ten days later and his doctor advises regular exercise. His wife, however, wants him to wait a bit longer before exercising for his heart to get a bit stronger. Two months later he still finds it an effort to go to work but his doctor says there is nothing wrong with his heart.

These are only two examples of a common scenario among patients after heart attacks and bypass surgery in this country. Saman was not given the correct advice about exercise but Chandana was. Their stories highlight the problem with the aftercare of coronary patients due to poor awareness of the concept of Cardiac Rehabilitation(CR) both among patients as well as health professionals.

CR is an essential part of the aftercare of those recovering from heart attacks and bypass surgery.

What is Cardiac Rehabilitation (CR) ?

In short, it is a process by which, recovery of a heart patient is made quicker and also complete. Medication alone cannot do this.

After a heart attack or bypass surgery, the patient is confined to bed for few days to reduce the physical stress on the recovering heart. As a result two things happen. The healthy part of heart muscles also starts resting and so the volume of blood, the heart normally pumps gets less. Thus, after initial recovery, when the patient tries to engage even in minor activity like walking to the toilet, it becomes a huge effort because the heart doesn't pump as effectively as it used to.

To add insult to the injury as it were, the muscles in the arms, legs and trunk ( called peripheral muscles) too adopt the same lazy attitude during the enforced rest and now virtually refuse to work with the same efficiency as before. This phenomenon is described as peripheral muscle deconditioning and plays a major role in delaying the recovery from a heart attack or bypass surgery.

The net result is that the heart now has to do more work to get those muscles to do the job, by having to pump more blood and oxygen into them. Unfortunately it is the worst time to make such a demand of the heart because the heart itself is struggling to put its own house in order because the heart muscle itself has got weaker either due to the attack or due to bypass surgery.

The result is a double insult on the heart itself. A weaker heart is called upon to do more work. This can at times be a disaster - a second heart attack or even death.

What is done in CR?

One major component of CR is to improve the deconditioning of muscles and thereby reduce the extra burden on the recovering heart. Therefore a graded exercise programme to suit the level of recovery of the heart in the aftermath is an important element of CR. As much as a drug, exercise too needs to be given in the correct dose. Therefore, a proper Exercise Prescription should be worked out to suit the exercise tolerance of the patient. Too low intensity exercise is ineffective and too high level of exercise is harmful.

The art and science of CR is in working out the correct dose of exercise to suit the recovery level of the heart patient. For this purpose an initial assessment of the patient is needed. This sometimes includes an exercise ECG and Aerobic Fitness Assessment using a special treadmill. From the results of such testing a suitable intensity of exercise is prescribed either in terms of a speed or a Target Heart Rate. The patient is given a heart rate (pulse rate) at which he or she should exercise for a particular time period or is given a distance to walk in a particular time. This is the Exercise Prescription, very much like a drug prescription containing the dose, the type and the duration, frequency etc of the exercise the patient should take. Exercise after all, should be considered as a drug because both too little and too high doses are not good.

As a patient recovers, his or her exercise prescription is upgraded in stepwise manner. This process can take as long as 3- 6 months depending on how fast one recovers. In CR, patients are initially given exercise under supervision.

There are two advantages in this method of supervised exercise in CR.

1. As the patient does the exercise under supervision in CR he or she feels confident to do it and often finds to his joy, that he can do more than what he thought he could. This gives a kind of psychological boost.
2. An improvement in the fitness level as indicated from results of a repeat assessment of Aerobic Fitness level after a course of exercise, would act as a positive feedback for the patients to continue his exercises with renewed vigour.

How much should be the heart rate of a normal person on exercise ?

Well, it should vary according to the initial fitness level. A person with moderate fitness could exercise at a heart rate of 70% of his predicted maximal heart rate(MHR). (Predicted maximal heart rate is 220- age in years). If you are 40 years, your MHR is 180 and 70% of that would be 126/Min. This is called Target or Training Heart Rate (THR). That is the suitable heart (pulse) rate for that person during exercise.

If the level of fitness is low as in the case of a heart patient during recovery, he or she is given a lower percentage of MHR, say for example 50% or so. As the fitness level improves the prescription is upgraded by a person with experience in CR.

What happens if you either exceed the THR or don't reach it?

Both are not good. If you don't reach THR that means your heart is not given sufficient stimulus for adaptation and there won't be an improvement in the aerobic fitness level. On the other hand if you exercise excessively you may face the danger of another heart attack or even death as in the case of some marathon runners. That is why one should know the aerobic fitness level before undertaking exercise especially if vigorous. This is valid advice even for normal people.

What is Aerobic Fitness(AF)?

It is a measure of your efficiency in handling oxygen at tissue level in your body. The higher the efficiency, the higher the amount of oxygen you could take into your body for a minute and the higher would be your AF. After a course of exercise in both normal people as well as heart patients, AF improves. That is why they feel less tired after effort because the heart has to beat a lesser number of times to get the same amount of oxygen to the tissues.

What else do you do in CR?

The rest of CR is mainly aimed at secondary prevention - to prevent the person getting a second heart attack. In this respect Lipid Management (including cholesterol) is important. We also screen them for Metabolic Syndrome ( a kind of forerunner of heart disease, diabetes and stroke etc). Advice is given on lifestyle modification, stress reduction, cessation of smoking, resuming sexual activity etc. We also help with weight management by offering dietary advice.

They are given a booklet containing almost all cooked Sri Lankan foods with their calorie values per portion. This helps them identify and avoid high calorie foods and also those with high saturated fats. We give them mind body counselling too.

What is Mind Body Counselling(MBC)?

Western medicine now accepts that the mind has a healing power on the body. That is why for example, meditation is now accepted as promoting healing of cancers. There is a lot of evidence in heart disease too, that mind can influence healing. So in MBC, a counsellor explains the basis of how mind influences the body through PNIE (Psycho Neuro Immune Endocrine) system and how one can get the mind to influence the body. Concentration of mind or one pointed mind helps the release of various emotional peptides from the brain. These peptides have now been shown to have healing powers especially in cancer, heart disease, diabetes etc.

(The writer is Consultant Physician at the Matara Cardiac Rehabilitation Centre)