Main Messages
Chapter 17: Exercise Training in Coronary Heart Disease
Exercise training provides a wide range of cardio- protective benefits both for the healthy population and for the coronary patient. Over the years phys- ical training has remained the cornerstone of com- prehensive cardiac rehabilitation worldwide. In this chapter the numerous effects of exercise train- ing are described and the risks of training are mentioned. New knowledge on the cellular level, i.e. endothelial function, is included. Thus, the rationale for the use of exercise training compo- nents in cardiovascular prevention and rehabili- tation remains convincing and unaltered. The chapter concludes with recommendations for pre- scribing physical activity and maintaining physical fitness in patients with coronary artery disease.
Chapter 18: Exercise Training in Diabetes Mellitus: An Efficient but Underused Therapeutic Option in the Prevention and Treatment of Coronary Artery Disease
Diabetes mellitus is one of the major risk factors for coronary artery disease. The disease pro- gresses faster in diabetic patients and is associated with a worse prognosis. Although bypass surgery or percutaneous interventions with stent implan- tation provide quick symptomatic relief for patients with stable coronary artery disease it has no substantial prognostic benefit, except in
patients with a significant stenosis of the left main stem or proximal left coronary artery.
A multifactorial intervention including dietary measures, blood glucose control, antihypertensive treatment, and regular physical exercise does have a positive influence on the modifiable risk factors, and improves cardiovascular fitness and angina- free exercise tolerance.
As shown by the United Kingdom Prospective Diabetes Study (UKPDS) and others it is of utmost importance to keep HbA1c levels <6.0% and LDL cholesterol levels <2.5mmol/L (100mg/dl) in order to reduce the incidence of cardiovascular events. Since the incidence of diabetes mellitus correlates inversely with the degree of physical activity, regular physical exercise (e.g. 30 min/day of aerobic exercise at a moderate intensity) can cut the risk for impaired glucose tolerance by half and the diabetes risk by up to three-quarters.
Endurance training is recommended for every- body including patients with stable coronary artery disease. Energy consumption should ideally be between 1000 and 2000 kcal/week, which corre- sponds to 3–5 hours of submaximal endurance train- ing per week. This has been shown to lead to increased exercise performance; it also improves the cardiovascular risk profile, reduces the cardiovascu- lar complication rate, improves myocardial perfu- sion, and slows the progression of coronary artery disease.Furthermore,endothelial function improves in patients with diabetes mellitus type 2 after 6 months of an intensive program of secondary pre- vention focusing on daily aerobic exercise training.
Exercise training is an effective therapeutic method which is largely underused and
Section III
Exercise Training in Heart Disease
122 Exercise Training in Heart Disease
under-prescribed. In order to reduce the risk of atherosclerosis or to attenuate the progression of the disease, awareness on the part of physi- cians and patients has to increase so that this effective “drug” is incorporated into the daily life of patients.
Chapter 19: Exercise Training in Heart Failure
The upcoming epidemic of chronic heart failure (CHF) is inevitable in an aging society. The pre- valence of CHF increases with age and reaches 10% among individuals >75 years. Disease- associated morbidity and disability are especially high among elderly CHF patients who account for more than three-quarters of all CHF-related hospital admissions. As a consequence, adjunctive therapeutic interventions are necessary aimed at improving exercise capacity and sustaining patients’ ability to maintain an independent life.
Before initiating an exercise-based interven- tion in a CHF patient several important con- traindications need to be ruled out: Cardiac decompensation in the previous 3 months, progressive worsening of exercise tolerance or dyspnea at rest or on exertion over the previous 3–5 days, myocardial ischemia during low- intensity exercise (<2 METs, <50W), uncontrolled diabetes, acute systemic illness or fever, recent embolism, thrombophlebitis, active pericarditis or myocarditis, myocardial infarction within the previous 3 weeks, and new onset atrial fibrillation.
Before enrolling patients with CHF into a train- ing program they should be in a stable condition without clinical evidence of fluid overload. A typical patient evaluation should be performed by an experienced cardiologist and involves: medical history, clinical examination, a resting ECG, a symptom-limited ergometry, and echocardiogra- phy. Other supplementary options are: Holter ECG, 24-hour blood pressure measurements, stress echocardiography, chest x-ray, and, in a few cases, evaluation of left ventricular filling pres- sures with a Swan – Ganz-catheter under stress conditions. If the clinical status of a patient is unclear and previous examinations/tests are lacking, invasive diagnostic measures should be
undertaken in order to clarify the situation. It should be underlined that patients included in training studies have to be on optimized medical therapy and in a stable clinical condition for at least 4 weeks before the initiation of the training program.
Although the prescribed training programs vary widely with regard to exercise type and intensity it is generally recommended to start low and go slow: One should start with a workload of 50% of peak oxygen uptake for 5–10 minutes.
When well tolerated, first the training duration per session, then the number of sessions per day should be increased. Finally, workload may gradually be increased to 70% of peak oxygen uptake.
While exercise interventions in CHF require a certain amount of enthusiasm and perseverance on the physician’s side they are clinically highly rewarding: Exercise capacity may be increased by 20–30% and meta-analyses indicate a 35% reduc- tion in all-cause mortality and a 28% reduction in hospitalization.
Chapter 20: Exercise Training in Valvular Heart Disease
Asymptomatic or mildly symptomatic patients with valvular heart disease are usually not included in medically supervised exercise training programs as part of the conservative manage- ment. However, physical conditioning and indi- vidually tailored exercise training are advisable for most patients after valve replacement, taking into account left ventricular function, previous level of training, the type of valve replaced, pulmonary hypertension, and heart rate. The general circulatory responses to exercise are of benefit to most of these patients, and could contribute to an overall improvement in the quality of life.
Chapter 21: The Role of Sports in Preventive Cardiology
There is wide documentation that physical activ- ity reduces cardiovascular morbidity and mortal- ity. The effect is more pronounced on increasing activity; it also has to be regular. In addition to
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the effect on classical risk factors, a positive effect on endothelial function also has been demonstrated. A similar effect is demonstrated by increasing fitness, and also when the effect of fitness on cardiovascular risk factors is corrected for. However, physical activity is more important, and the effect of fitness probably is induced by physical activity.
The risk of physical activity is by far out- weighed by the benefit. Thus, the risk of sudden death is four times higher in persons not exercis- ing than in those who exercise regularly. However, in young athletes the risk of sudden death is increased compared to sedentary persons of the same age, and the prevention of sudden death in this population also is an aspect of preventive cardiology. Myocarditis only accounts for 10%
of deaths, but nevertheless physical training and competitions during febrile illness should be discouraged. Hypertrophic cardiomyopathy is the most important cause of sudden death in this population, and in most cases can be detected by ECG at rest. According to the European re- commendations from 2005, a clinical examination and a standard ECG are sufficient in screening of competitive athletes aged 12–35 years.
Exercise ECG should be done in male athletes above 35 years and female athletes above 40 years with a high risk of coronary disease before recommending participation in sports competitions.
There are no clear data on the harmful long- term cardiac effects of athletic training, and there is clear evidence of increased longevity in athletes provided physical training is continued.
Thus the message is clear that unless physical activity is regular and persistent it has no documented effect on the prevention of cardio- vascular disease. Therefore, sports activity as a lifestyle has great potential as a tool in preventive cardiology. Involvement in sports for children and adolescents may be important in this regard.
Whereas there is good evidence that fitness in the young is a good predictor of cardiovascular health later in life, the data on physical activity are less solid.
However, one can state that sports in the young can have a positive effect on cardiovascular morbidity and mortality. One of the increasing
problems in this regard is juvenile obesity. This is also a sociocultural problem, as also is the lack of participation in sports and exercise in adolescents, which particularly affects female immigrants.
Thus there is good evidence to promote organized sports, which should be supported by families, community agencies, and schools.
Chapter 22: Advising Patients with Cardiac Disease and after Cardiac Interventions about Sports Activities
Physical exercise is often classified as dynamic and static. Dynamic exercise is usually advised in heart patients, but static exercise has been shown to be less hazardous than previously thought.
Competitive sports can be advised in several heart disorders, but in some cases must be dis- couraged. Due to pressure from athletic organiza- tions, the media, sponsors, and the athlete’s own ambitions and finances, the athlete often has a considerable motivation to carry on the activity, and recommendations are needed in order to give correct medical advice. In 1994 the American Bethesda Guidelines were published, and in 2005 Recommendations from the European Society of Cardiology were published. Grown up congenital heart disease patients benefit from regular exer- cise, and patients with ASD and VSD have no lim- itations in athletic activity 3 months after closure provided the ECG and echocardiogram are normal. In mild aortic and mitral regurgitation also all sports are allowed. This also is the case in well-controlled mild hypertension without additional risk factors and 3 months after suc- cessful ablation of paroxysmal supraventricular tachycardia.
In cardiomyopathies, however, competitive sports are not generally recommended, and in myocarditis competitions should be stopped for 6 months. In competitive athletes without symp- toms and a low-risk profile, exercise testing is not routinely recommended in males below 35 years and females below 45 years.
Recreational sports generally can be advised in heart patients. In heart failure, reduction of mor- tality has been demonstrated by physical training.
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(see Chapter 19) Generally, previous favorite sports should be encouraged, but in certain con- ditions there should be taken some precautions.
Thus contact sports should not be recommended in patients on warfarin treatment, in patients with Marfan syndrome, and after valve prosthesis.
Sports in which there is a risk of falls should not be advised because of the risk of syncopal attacks.
Scuba diving should be discouraged in recre- ational divers with decompression sickness with patent foramen ovale (PFO), in professional divers closure of the PFO should be performed.
