22 Advising Patients with Cardiac Disease and after Cardiac Interventions about Sports Activities

Introduction

Cardiac rehabilitation increases fitness and quality of life and should therefore be offered to all patients after acute cardiac events and interventions. After a rehabilitation program of 4–8 weeks further physical activity is impor- tant, and usually previous sports can be taken up at some level. In most cases this will be recreational sports, but sometimes also recom- mendations for competitive sports are needed after a cardiac event or diagnosis of a cardiac disorder.

Classification of Sports

Exercise is usually classified into dynamic (iso- tonic) and static (isometric) and the intensity as low, moderate, or high. Running is typical dynamic exercise and leads to increased cardiac output, oxygen consumption, and systolic blood pressure, whereas diastolic blood pressure may fall due to decreased peripheral resistance. Static exercise leads to pressure overload with little influence on oxygen consumption and cardiac output. Traditionally, dynamic exercise is pre- ferred in cardiac patients, but static exercise has been proved to be less dangerous then previ- ously thought. Table 22-1 gives an overview of the most common sport activities and their classification.

Competitive Sports in Cardiac Diseases

Cardiovascular disease may induce an increased risk of sudden death or deterioration of disease on competitive athletic activity; therefore recom- mendations are important to provide careful directions for physicians and consultant cardio- logists. By competitive athletes is meant individu- als of young or adult age who are engaged in regular exercise training and participation in official sports competitions. The recommenda- tions are particularly important in elite athletes due to the intense pressure they are exposed to by the media, athletic associations, and sponsors.

Protecting the athlete’s health is the paramount objective of the physician, and when the cardio- vascular risk appears to be unreasonably high, the physician should be responsible for the final deci- sion, with the aim to prevent adverse clinical events and/or reduce risk of disease progression.

The American guidelines were published in 1994.

In 2005 the European Society of Cardiology made new recommendations,

which are the basis for the following recommendations.

Grown up Congenital Heart Disease (GUCH)

Patients with congenital heart disease (CHD) reaching adulthood are a growing population.

Most of them require lifelong care. The hemo- dynamic situation of the patient with CHD varies considerably. This makes it impossible

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Advising Patients with Cardiac Disease and after Cardiac Interventions about Sports Activities

Hans H. Bjørnstad, Asle Hirth, Saied Nadirpour, and Britt Undheim

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to give recommendations that are valid in all cases. Nevertheless, studies suggests that GUCH patients benefit greatly from regular physical exercise and therefore only those patients who are likely to deteriorate as a con- sequence of regular physical exercise and/or those in whom exercise may trigger serious arrhythmias should be restricted from sport participation.

Shunts

Patients with closed or small atrial septal defect (ASD), ventricular septal defect (VSD), and persistent ductus arteriosus (PDA) with normal ECG and echocardiography have no exercise limitations. PDA with audible murmur and lesions with significant shunt need to be corrected and only low to moderate leisure sport activity is recommended until after catheter or surgical repair.

Tetralogy of Fallot (TOF)

Common hemodynamic alterations in TOF are abnormal right ventricular RV function, pul- monary valve insufficiency, and arrhythmia.

Most patients have no exercise restrictions and will benefit from increased physical activity. If significant residual disease is present the patient is not allowed to participate in competitive sport.

Transposition of the Great Arteries (TGA)

Patients with TGA corrected by arterial switch can perform all kinds of exercise if significant pul- monary stenosis, aortic insufficiency, and ischemia on exercise ECG have been ruled out.

Coarctation of the Aorta (CoA)

If no signs of residual CoA or recoarctation, no hypertension, no associated aortic stenosis, and normal exercise blood pressure response are

A. Low dynamic B. Moderate dynamic C. High dynamic

I. Low static Archery Table tennis Badminton

Bowling Tennis (doubles) Walking

Cricket Volleyball Running (marathon)

Golf Baseball* Cross-country skiing

Riflery (classic)

II. Moderate static Auto racing* Fencing Basketball*

Diving Field events (jumping) Biathlon

Equestrian* Figure skating* Ice hockey*

Motorcycling* Lacrosse* Field hockey*

Gymnastics* Running (sprint) Football*

Karate/Judo* Soccer*

Sailing Cross-country skiing

(skating) Running (mid/long) Swimming Squash*

Tennis (single) Team handball*

III. High static Bobsledding* Body building* Boxing*

Field events (throwing) Downhill skiing* Canoeing, Kayaking

Luge* Wrestling* Cycling*

Rock climbing* Decathlon

Water skiing* Rowing

Weight lifting* Speed skating

Windsurfing*

Symbols: *Danger of bodily collision. Increased risk if syncope occurs.

Source: Adapted and modified after Mitchell et al.¹

found, patients with CoA can perform all kinds of sports without limitations.

Complex Lesions

The majority of patients with more complex lesions will have some form of residual cardiac, pulmonary, or cerebral dysfunction. They have increased risk of arrhythmias and deterioration during heavy exercise, and only dynamic sport of low and moderate intensity and/or static sport of low intensity can be recommended. In this cate- gory would be patients with single ventricle, TGA corrected by Senning, Mustard or Rastelli opera- tions, and Ebstein anomaly. Patients with Eisen- menger syndrome or secondary pulmonary hypertension should only do low-intensity leisure sport activity.

Marfan Syndrome

These patients are at increased risk of aortic dis- section and sudden death during exercise and are not allowed to do any form of competitive sport.

So long as patients avoid sports with the risk of bodily collision, low and moderate dynamic leisure sport activity can be performed.

Valvular Disease Aortic Stenosis (AS)

Low–moderate dynamic and static sports are allowed in mild AS (mean gradient below 20 mmHg, area above 1.5 cm

, normal left ventricular (LV) function at rest and exercise). Exercise echocardiography can help to evaluate the devel- opment of the aortic gradient during exercise. Low dynamic/low static sports are allowed in moder- ate stenosis (mean gradient 21–49 mmHg, area 1–1.5 cm

, and normal LV function at rest and exercise).

Aortic Regurgitation (AI)

All sports are allowed in mild AI with normal LV size and function at rest and exercise and no arrhythmias.

Mitral Stenosis (MS)

All sports except high dynamic and high static are allowed in mild MS (area >1.5cm

, mean pressure

<7mmHg, pulmonary artery pressure below 35 mmHg).

Mitral Regurgitation (MI)

All sports are allowed in mild MI (regurgitation area <4cm

, normal LV size and function, normal exercise testing, sinus rhythm). In atrial fibrilla- tion and warfarin treatment, contact sports are not advised.

In moderate MI (regurgitation area 4–8 cm

, mild LV dilatation, normal LV function at rest and stress, no arrhythmias, no symptoms) low–mod- erate dynamic and low–moderate static sports are allowed.

Mitral or Aortic Artificial Valves

Recommendations are the same as for moderate MI.

In mild mitral regurgitation with atrial fibrilla- tion and adequate anticoagulation, all sports except contact sports are advised.

Cardiomyopathies and Myocarditis

Cardiomyopathy is the most important cause of death in young athletes.

Hypertrophic cardiomyopathy (HCM) has a prevalence of 0.5% and accounts for 30% of sudden deaths (SD) in young athletes in the US.

When the diagnosis is certain, competitive sports generally are not recommended. A differ- entiation from physiological hypertrophy is crucial.

However, low dynamic, low static sports may be allowed in athletes with a low risk profile accord- ing to history, physical examination, ECG, exercise testing (blood pressure response, optionally Doppler investigation of intraventricular gradi- ent), and Holter monitoring. In some cases determination of the genotype also may be done.

In these cases yearly follow-up should be carried out.

Dilated cardiomyopathy (DCM) is a far less

common cause of SD in athletes. Sometimes dif-

ferentiation from physiological hypertrophy with

dilatation may be difficult. In these cases, tissue

Doppler and exercise echocardiography may be

helpful in the differentiation. Generally, ejection

fraction (EF) in normal adaptation is above 50%

and there are no wall motion abnormalities.

A family history of DCM strongly suggests this diagnosis.

In definite diagnosis of DCM, competitive sports generally are not recommended.

However, low–moderate dynamic and low static sports may be recommended in low-risk cases where there is no sudden death in relatives, no symptoms, EF > 40%, normal blood pressure response on exercise testing, and no complex ven- tricular arrhythmias (Holter monitoring should be done).

Right ventricular dysplasia (ARVD) is an impor- tant cause of SD in young athletes, particularly in Italy where many athletes with HCM have been ruled out by screening. The diagnosis may be difficult, but can be suspected from ECG: RBBB is common. Negative T waves are present in more than 40% and ventricular arrhythmias with LBBB pattern are common.

In definite cases of ARVD, athletic competitions are not recommended.

Myocarditis and Pericarditis

Myocarditis accounts for about 10% of SD in young athletes and should be assessed by standard clinical examination included viral serology (particularly enteroviruses), ECG, and echo- cardiography (including tissue Doppler). In active myocarditis, athletic competitions are not recommended. Six months after onset com- petitions may be resumed provided there are no symptoms, normal LV function, and no arrhythmias assessed by ECG, echocardiography, exercise ECG, and Holter monitoring. A new car- diological assessment should be done every 6 months.

Even if myocarditis is not the most common cause of SD, there are good reasons for caution on training and competitions during and immedi- ately after infections. There are also experimental data suggesting that myocarditis is worsened by physical training.

Furthermore, there is some evi- dence that infections increase the risk of acute coronary episodes.

Pericarditis may be followed by a myocarditis and should preclude athletic activity in its active stage. The same examinations should be done as for myocarditis. In clinically isolated pericarditis,

competitions may be resumed 3 months after clin- ical onset of disease, with the same investigations being done as in myocarditis before resumption.

Cardiological control after 6 months is recommended.

Hypertension

Hypertension is defined as systolic blood pressure (BP) 140 mmHg or above and/or diastolic BP 90 mmHg or above, or patients on antihyperten- sive treatment. The prevalence is approximately 15%, 30%, and 55% in males aged 18–39 years, 40–59 years, and above 60 years. Corresponding numbers in females are 5%, 30%, and 65%.

However, 25% of patients with hypertension by conventional measurements have a normal blood pressure on 24-hour monitoring.

According to a meta-analysis by Fagard and Amery,

exercise reduces systolic/diastolic blood pressure by 6/7 mmHg in borderline hypertensives and 10/8 mm in hypertensives.

Athletic competitions without any restrictions can be recommended in hypertensives with well- controlled mild hypertension without additional risk factors (dyslipidemia, smoking, abdominal obesity, family history of premature coronary disease).

All sports except high static, high dynamic sports can be recommended in well-controlled moderate hypertension or mild hypertension with one or two risk factors.

All sports except high static sports can be rec- ommended in well-controlled severe hyperten- sion without risk factors or well-controlled mild/moderate hypertension with three or more risk factors or target organ damage.

Low–moderate dynamic and low static sports are recommended in well-controlled hypertension with associated clinical conditions (cerebrovascular, coronary or peripheral artery disease, renal disease, retinopathy) or well- controlled severe hypertension with risk factors.

Ischemic Heart Disease (IHD)

IHD accounts for most exercise-related sudden

deaths in individuals above 35 years. Although the

benefit of regular physical activity outweighs the

risk, sports participation should be individually advised in patients with IHD.

Necessary investigations are history, resting and exercise ECG (and in some cases stress echocardiography), echocardiography, coronary angiography and Holter monitoring included a training session.

Low risk for exercise-induced cardiac events in patients with evidence of IHD is characterized by ejection fraction above 50%, normal exercise capacity, absence of exercise-induced ischemia at lower steps, absence of significant coronary stenosis ( >70% of major coronary arteries or >50%

of left main stem) and stable clinical condition.

After an intervention outpatient rehabilitation should be completed before considering sports competitions.

Athletes with a high-risk profile ( >5% global risk according to SCORE) should be evaluated by maximal exercise ECG. If this is negative, the risk of a major cardiac event during physical activity can be considered small. If there is a pos- itive stress test, further diagnostic evaluation should be done to rule out coronary disease.

In asymptomatic athletes with a low-risk profile, routine use of exercise testing is not recom- mended in men below 35 years and women below 45 years.

Myocardial ischemia also may be induced by other conditions than atherosclerosis:

– cocaine abuse

– congenital coronary artery anomalies are asso- ciated with sudden death in young athletes, and are often not revealed by exercise testing – in myocardial bridging, however, the risk is not

high; the same probably is the case in syndrome X.

In spasm angina, the clinical course is unpre- dictable and competitive sports activity generally should be discouraged unless the condition has been asymptomatic for 1 year.

Arrhythmias

Sinus Bradycardia (£30 beats/min and/or sinus pauses 3–3.5 s)

Athletes can participate in all sports if there are no symptoms and no cardiac disease.

Atrioventricular (AV) Block

Individuals with AV block grade I and second- degree AV block type Wenckebach (Mobitz type I) can participate in all sports if there are no symp- toms, no structural heart disease, and no progres- sion of AV block during exercise.

Those with Mobitz type II or third-degree AV block can participate in low–moderate dynamic, and low–moderate static sports in the absence of symptoms, cardiac disease, ventricular arrhyth- mias during exercise, and if the resting heart rate is >40 beats/min.

Paroxysmal Supraventricular Tachycardia (AVNRT or WPW Syndrome and AVRT) Catheter ablation is recommended.

Affected individuals can participate in all sports following successful catheter ablation after an asymptomatic period of more than 1 month, and no cardiac disease.

If ablation is not performed and AVNRT is spo- radic without hemodynamic consequences, and without relation to exercise, individuals can par- ticipate in all sports, except those with increased risk (see Table 22-1).

WPW Syndrome and Atrial Fibrillation or Flutter Catheter ablation is mandatory.

Participation in all sports is possible following successful catheter ablation after an asympto- matic period of more than 1 month, and if there is no cardiac disease.

Asymptomatic WPW Pattern (Pre-excitation Pattern) on ECG Catheter ablation is recommended.

Asymptomatic athletes at low risk (normal hearts without inducible AF or AVRT) and not ablated can participate in all sports, except sports with increased risk (see Table 22-1).

Atrial Fibrillation (AF)

Paroxysmal AF: individuals can participate in all

sports after 3 months without AF recurrence

under rhythm control therapy in the absence of

cardiac disease or WPW.

Permanent AF: a ventricular rate comparable to that of an appropriate sinus tachycardia during exercise should be guaranteed before returning to competitive sports.

Asymptomatic athletes with structural heart disease can participate in competitive sports as determined by the limitations of the cardiac abnormality.

Athletes who require anticoagulation therapy with warfarin should not participate in sports where there is a danger of bodily collision or trauma.

Atrial Flutter

Catheter ablation is mandatory.

Athletes can participate in all sports 3 months after successful ablation without recur- rence of the arrhythmia and no cardiac disease or WPW.

Asymptomatic athletes with structural heart disease can participate in competitive sports as determined by the limitations of the cardiac abnormality 3 months after successful ablation without recurrence of arrhythmia.

Athletes not treated by catheter ablation should not return to full participation to all sports until they are free of arrhythmia recurrence for 6 months with or without drug therapy.

Ventricular Premature Beats (VPB)

Individuals can participate in all sports in the absence of cardiac disease, arrhythmogenic con- dition (cardiomyopathies, ischemic heart disease, and channelopathies), family history of sudden death, symptoms (syncope), worsening on exer- cise, and frequent and/or polymorphic VPBs and/or frequent couplets with short RR interval.

Holter monitoring, exercise testing, and echocar- diography is recommended in frequent VPBs.

Nonsustained Ventricular Tachycardia (NSVT), Slow Ventricular Tachycardia (Idioventricular Accelerated Rhythm), Fascicular VT, Right Ventricular Outflow Tachycardia (RVOT)

Athletes can participate in all sports, except those with increased risk (see Table 22-1), in the absence of cardiac disease, arrhythmogenic condition, family history of sudden death, symptoms

(syncope), relation with exercise, and multiple episodes of NSVT or VT over 24 hours and/or with short RR interval. Athletes with symptomatic fascicular tachycardia or RVOT who undergo catheter ablation can participate in competitive sports 3 months after successful ablation if asymptomatic and without recurrence of tachycardia.

Malignant Ventricular Tachycardias (Sustained VT, Polymorphic VT, Torsade de Pointes, and

Ventricular Fibrillation)

All competitive sports are contraindicated.

An exception is represented by ventricular arrhythmias occurring in the context of acute and completely reversible conditions, such as myocarditis, commotio cordis, acute electrolytic depletion, when the cause has been resolved.

Arrhythmogenic Conditions (Long QT Syndrome, Brugada Syndrome)

All competitive sports are contraindicated.

Syncope

Neurocardiogenic: Athletes can participate in all sports, except those with increased risk.

Arrhythmic or primary cardiac: See specific cause.

Implanted Pacemaker

Patients can participate in low–moderate dynamic and low static sports, except those with risk of bodily collision, if there is normal heart rate increase during exercise, no significant arrhythmias and normal cardiac function.

Patients with specific heart disease can partici- pate only in sports consistent with the limitations of the arrhythmia and the underlying heart disease.

Implantable Cardioverter Defibrillator (ICD)

Patients can participate in low–moderate

dynamic and low static sports, except those with

risk of bodily collision, if normal cardiac function,

no malignant VTs and at least 6 months after

the implantation or the last tachyarrhythmia

intervention.

Recreational Sports in Certain Groups of Patients

Heart failure

Exercise training is an important part of the treatment of heart failure patients, improving functional status and also reducing mortality.

Improvement by exercise training can be obtained after resynchronization therapy. Before starting an exercise training program, the condition should be stable and the fluid volume status should be controlled. Complete cardiological investigation is necessary, ensuring that there is no ischemia, which should be treated with revas- cularization. An exercise test is mandatory; if pos- sible ergospirometric evaluation should be done.

Anaerobic threshold is a good guideline for the level of training, particularly in atrial fibrillation where heart rate is not a reliable parameter of intensity. Previously, only dynamic exercise was advocated, but moderate isometric exercise has also turned out to be feasible and safe. Lactate measurement and (in sinus rhythm) pulse watch monitoring may be helpful. Competition sports usually are not advisable in heart failure.

Heart Transplant Patients

In order to regain a good functional status with good quality of life, physical training is crucial after heart transplantation, and participation in long distance races is possible.

However, it is controversial whether training modifies the rein- nervation.

Also resistance exercise is beneficial for counteracting osteoporosis and skeletal muscle myopathy.

However, due to sympathetic denervation, hypotension during resistance exer- cise is a problem in about 25% of patients, partic- ularly when lifting above the level of the heart.

Therefore exercises improving venous return should be done (cool-down walk 2–5 min, alter- nate upper body and lower body exercises). In severe osteoporosis, resistance exercises should be done with care.

Children with Cardiac Diseases

Children under the age of 10 with diseases where the heart is involved should be allowed to perform

physical activity without restrictions. A restrictive attitude in this age group is not necessary since the children will limit themselves. Many children with heart disease have impaired exercise capac- ity due to overprotection and lack of exercise experience. On the other hand, parents should know if their child has a cardiac disease that will need restrictions in adolescence or adult life in order to direct their hobbies or physical training towards non-competitive, moderate-intensity activities.

The most important ones have already been described above. In addition, children with cardiomyopathy or disorders leading to cardiomyopathy, children with arrhythmic disorders such as long QT syndrome, arrhythmic right ventricle dysplasia and Brugada syndrome, and children with suspected Marfan syndrome should be mentioned. Children with Kawasaki syndrome should be restricted from moderate- and high-intensity sport until 3 months after recovery from disease/disappearance of coronary abnormalities.

Heart Surgery

Following surgery, training can start after 2–4 weeks guided by a maximal exercise test 3–5 weeks after the operation. A rehabilitation program is recommended before return to com- petitive or leisure-time sports. The complete healing of the sternotomy usually takes 3 months, which has to be considered when taking up sports.

Generally earlier sports can be resumed, but contact sports should be avoided in warfarin treatment and in artificial valves. If there are significant pericardial effusions, training should be postponed.

Endocarditis

Prophylaxis should be given according to standard rules. Sports should be discouraged during fever- ish illness.

Anticoagulation

Sports with risk of bodily collision (see Table 22-

1) should be avoided.

Practical Advice on Sports in Cardiac Rehabilitation

Contact Sports (Table 22-1)

These should be avoided in patients on warfarin, with Marfan syndrome, valve prosthesis, and con- genital heart disease and conduit.

Isometric Sports

Blood pressure may increase to 320/250 in weightlifters.

One study showed 311/184 with Valsalva, 198/175 without Valsalva.

Generally, isometric sports are not advised in patients with hypertension.

High-Risk Sports (Table 22-1)

Sports where there is a risk of falling down (climb- ing, parachuting) or being trapped (diving, swim- ming) should not be performed if there is a risk of syncope.

Swimming

Holter monitoring during swimming has shown increased arrhythmias in some patients. After open heart surgery, breast swimming can be started cautiously after 2 months, but may still cause some pain for 2 more months. It corre- sponds to an energy load of at least 75 W.

Scuba Diving

Non-randomized studies suggest an increased risk of decompression sickness (DCS) in patients with patent foramen ovale (PFO).

Those who experience DCS despite a safe diving profile should be screened for PFO by transesophageal echocardiography (TEE). If PFO is found, the recreational diver should give up his hobby. Pro- fessional divers should be offered catheter closure of the PFO. Diving can then be resumed after 3 months.

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