CORONARY CALCIFICATION BY COMPUTED TOMOGRAPHY

(CT).Since the last version of these guidelines, the widespread

dissemination of noninvasive techniques such as

EBCT, or even more recently, multi-slice gated CT, has

markedly increased the number of individuals, including

competitive athletes, who may be diagnosed with atherosclerotic

CAD. Although exceedingly rare in young persons

(6% of men and 3% of women 20 to 29 years of age), the

presence of coronary calcium increases substantially with

age, such that for master’s athletes, age 40 to 49 years,

approximately 41% of men and 13% of women may have

measurable coronary calcium (13). Among individuals age

50 to 59 years, 68% of men and 27% of women have

documented coronary calcium (13). There is compelling

evidence that the presence of any coronary calcium indicates

underlying atherosclerosis (14) and that increasing coronary

calcium scores are associated with increased CAD risk (15).

The coronary calcium score that warrants additional evaluation

in asymptomatic competitive athletes is unknown,

although scores of more than 100 (15) have been associated

with increased risk for coronary events (16) in the general

population compared to patients with no coronary calcium.

It is unknown whether the risk of coronary events during

intense exercise is increased in the presence of this or lesser

amounts of coronary calcium. Nevertheless, for the purpose

of the present document, athletes with coronary artery

calcification scores more than 100 should undergo the same

evaluation as those with more clinically evident CAD.

RISK ASSESSMENT.A paucity of data exists in competitive

athletes directly relating the presence and severity of CAD

to the risk of athletic participation. This requires that these

recommendations for athletes with CAD be based in part

on observations obtained from non-athletes with CAD.

Nevertheless, it is likely that risk is increased to some degree

whenever coronary atherosclerosis is present. It is also likely

that the risk of exercise-related events increases with the

extent of disease, LV dysfunction, inducible ischemia, and

electrical instability, and that the risk increases with the

intensity of the competitive sport and the intensity of the

participant’s effort.

Evaluation.

1. Athletes with CAD diagnosed by any method including

coronary artery classification scoring more than 100,

coronary angiography, evidence of inducible ischemia,

or prior coronary event, and who are undergoing evaluation

for competitive athletics, should have their LV

function assessed.

2. These athletes should undergo maximal treadmill (or

bicycle) exercise testing to assess their exercise capacity

and the presence or absence of provocable myocardial

ischemia. Exercise testing should approximate as closely

as possible the cardiovascular and metabolic demands of

the planned competitive event and its training regimen.

Despite such simulation, graded exercise testing cannot

replicate the cardiovascular stress produced by the sudden

bursts of activity, the combination of high dynamic

and static exercise, such as rowing, or the sustained

bouts of exercise required by athletic training and

competition. Therefore, standard clinical exercise tests

may not be appropriate for the evaluation of athletes

with coronary heart disease.

RISK STRATIFICATION.Two levels of risk can be defined on

the basis of testing.

Mildly increased risk. Athletes with CAD diagnosed by

any method are judged to be at mildly increased risk if they

demonstrate all of the following:

1. Preserved LV systolic function at rest (i.e., ejection

fraction greater than 50%).

2. Normal exercise tolerance for age, demonstrated during

treadmill or cycle ergometer exercise testing: greater

than 10 metabolic equivalents (METS), or greater than

35 O2/kg-min if less than 50 years old; greater than 9

METS, or greater than 31 ml O2/kg-min for 50 to 59

years old; greater than 8 METS, or greater than 28 ml

1349 JACC Vol. 45, No. 8, 2005 Thompson et al.

April 19, 2005:1348–53 Task Force 6: Coronary Artery Disease

O2/kg-min, if 60 to 69 years old; and greater than 7

METS, or greater than 24 ml O2/kg-min, if greater

than or equal to 70 years old. It should be noted that

young, highly competitive endurance athletes should

have maximal oxygen uptakes far in excess of ranges

regarded as normal, which in fact may represent substantial

functional impairment in this population.

3. Absence of exercise-induced ischemia and exerciseinduced

or post-exercise complex ventricular arrhythmias,

including frequent premature ventricular contractions

(greater than 10% of beats/min), couplets, or

ventricular tachycardia.

4. Absence of hemodynamically significant stenosis (generally

regarded as 50% or more luminal diameter narrowing) in

any major coronary artery by coronary angiography.

5. Successful myocardial revascularization by surgical or

percutaneous techniques if such revascularization was

performed.

Substantially increased risk. Athletes with CAD identified by

noninvasive or invasive testing are judged to be at substantially

increased risk if they demonstrate any of the following:

1. Impaired LV systolic function at rest (i.e., ejection

fraction less than 50%).

2. Evidence of exercise-induced myocardial ischemia or

complex ventricular arrhythmias.

3. Hemodynamically significant stenosis of a major coronary

artery (generally regarded as 50% or more lumen

diameter narrowing) if coronary angiography was

performed.

The American College of Cardiology/AHA guidelines

on exercise testing note that it is not necessary to stop

beta-blockers before routine exercise testing, although this

practice may reduce the diagnostic and prognostic value of

the test (17). The decision whether or not to stop betablocker

therapy before exercise testing of athletes should be

made on an individual basis. Stopping beta-blockers and

other anti-ischemic mediations before testing may be useful

to more closely approximate the probable risk if the athlete

either intentionally or unintentionally does not take these

medications before competition, or when certain athletic

regulatory bodies prohibit beta-blockers. If anti-ischemic

medications are stopped, this should be done carefully to

avoid a potential hemodynamic rebound effect, which could

lead to accelerated angina or hypertension.

Coronary arteriography is not required to determine

eligibility for competition in patients with known CAD,

and no evidence of inducible ischemia, but is recommended

in athletes with exercise-induced ischemia who choose to

participate in sports against medical advice. Such studies

may identify coronary lesions that may be better managed by

percutaneous or surgical myocardial revascularization procedures

to relieve exercise-induced ischemia and potentially

to reduce exercise-related risk.

The panel wishes to emphasize that the following recommendations

are prepared as a guidelines for permitting

participation in competitive sports. Restrictions in the following

recommendations, therefore, should not be misinterpreted

as an injunction against regular physical activity as

opposed to athletic competition. Indeed, regular and recreational

physical activity and moderate-intensity exercise

training are recommended for patients with CAD for its

general cardiovascular benefits (1).

Recommendations:

Date: 2016-03-03; view: 726