The topic might seem a contradiction, how can it be possible to engage in intense sport with an operated heart? It is possible, but not for everyone and not in each case. The topic is complex and requires a differentiated approach. The major components of the equation are the following:
- Nature of the disease
- Functional condition of the heart
- Response of the heart and of the whole cardiovascular system to the operation
- Presence of any residual or other disease with particular relevance to intense sport
- Attitude of the patient and his/her family
- Sports history of the patient
Some definitions first. What do we mean with “intense sport”?
In sports and particularly exercise testing, the rating of perceived exertion(RPE), as measured by the Borg rating of perceived exertion scale (RPE scale, Fig. 1), is a frequently used quantitative measure of perceived exertion during physical activity. In medicine this is used to document the patient’s exertion during a test, and sports coaches use the scale to assess the intensity of training and competition. The Borg RPE scale is a numerical scale that ranges from 6 to 20, where 6 means “no exertion at all” and 20 means “maximal exertion.” There is a revised version more specifically looking at breathlessness. According to the original Borg scale under intense sport, we understand the upper half of orange and the whole red category.
The concept of perceived exertion implies that intensity of physical activity is relative. The intensity (measured in m/min, km/h or Watts/min) perceived by an elite athlete as 11-12 in the Borg scale will be probably be perceived as 17-18 by a “normal” person engaging in intense sport and as 20+ by someone who does sport occasionally.
In general, people with heart conditions should avoid sudden and intense outbursts. Intense outbursts in any activity let blood pressure increase rapidly to very high values, which stress and harm the heart muscle acutely. The importance of adequate warm up cannot be overemphasized. Warming up prepares the organism and the cardiovascular system by dilating the peripheral blood vessels (mainly the small arteries regulating blood flow into the tissues) and by increasing the metabolic rate. Increasing the intensity of exercise gradually avoids the harming effect of high blood pressure.
There are specific heart conditions in which intense sport is not allowed. Among them diseases which induce hypertrophy of the heart muscle (such as aortic valve stenosis), leaking heart valves (if graded more than mild) and known aneurysms of the aorta.
Normally all these conditions (except aneurysms) cause symptoms on exertion, mainly shortness of breath, so they get detected. In many cases, however, and oddly enough also in people with regular physical activity, those conditions do not cause any perceivable symptoms. Therefore, seeing a cardiologist and having an echocardiography (i.e. a non invasive ultrasound exam of the heart) for all those engaging in intense sport is surely the best approach to exclude asymptomatic heart disease.
How does cardiac surgery fit in in this context? What is my advice to patients regarding intense sport?
There is no answer that fits all! As every patient is individually different from any other, the approach is individualized. I usually start exploring beyond the medical history, inquiring about the sport history, too. This gives me an understanding of the usual intensity, the frequency, the attitude (competitive or not) and the importance of sports in the patient’s life and serves as a guide for the postoperative target. Sometimes surgery can be more specifically individualized for this purpose, be it choosing the surgical access or the type of valve or a hybrid approach etc. Then the conditions of the heart muscle and the probabilities of recovery (if heart function has suffered) are evaluated. Sometimes we need to wait and monitor the recovery for several months after surgery before giving more liberal advice regarding sports. The so called remodelling of the heart muscle is a slow process.
I explain to the patients that even the least invasive cardiac surgery, especially if the extracorporeal circulation has to be used (which is normally the case), induces an avalanche of inflammatory reaction in the body, which results in the so-called post-aggression reaction. In this function mode, the body draws on its best source of energy, the own muscles, to guarantee the increased energetic expenditure. At the end of the hospitalisation we have to face a net loss of lean body mass (muscles), which has to be rebuilt. This is the main reason why we offer and encourage actively our patients to enrol in a rehabilitation programme. Adequate, controlled and softly progressing physical activity is the best way to inverse the post-aggression metabolism and allow the muscles to rebuild.
The more frequent advice to patients, who want to practice their sport regularly after surgery, is to go through the rehabilitation program, have the cardiac evaluation at its end and then assess the options together. With a normal or near-normal heart function and no aneurysm involved, it is possible (if desired) to re-engage in sports at a Borg scale level of 11-12 and slowly progress to 13-14. It is important to stay alert, self-critical and avoid overdoing. It is not possible to return to best personal record levels within two or three weeks! A close follow-up is necessary; usually the prescriptions of medicines need some fine-tuning. If patients succeed in maintaining a regular physical activity, many positive effects happen: blood sugar control improves, blood pressure control improves, body weight control improves!
For patients with limited heart function with poor probability of full recovery the advice is to continue to exercise, not to abandon physical activity after the rehab program is concluded. If they practiced sport before undergoing cardiac surgery we encourage to re-start at a Borg scale level of 10 to maximal 14. For those who didn’t have a favorite physical activity before, we suggest active walking or nordic walking, cycling or lane swimming, aiming to achieve the above mentioned perceived level of exertion.
A special group of patients are those seriously active in sports. They know and listen to their body, are used to train according to heart rate defined zones, know their anaerobic threshold in terms of heart rate and many of them know also their maximal oxygen consumption (VO2), as real athletes do. Belonging myself to this group (although at a relative low level!) finding a common ground and understanding is usually easy. Being understood is the first step to relax, as patients normally fear that their cardiac surgeon would prohibit intense athletic activity after surgery. While I cannot a priori guarantee that they can go one at the same intensity, I obviously not exclude it, on the contrary, if it is compatible with their disease and surgery I certainly encourage it. It cannot be immediately after the operation, the post-aggression syndrome hits everyone. After rehab, structured training can commence. Also in this context, there is no solution that fits all situations: the individual approach and honest dialogue is fundamental.
Many patients operated for various heart conditions re-engaged successfully in their sport: serious cycling, long-distance swimming, competitive sailing, running. As in life without cardiac surgery, not everyone of us can practice sport at high levels of intensity and endurance. This is obviously more than true after cardiac surgery. An individual and differentiated approach is crucial, this is my strong recommendation!