Prevalence of Subclinical Coronary Artery Disease in Masters Endurance Athletes With a Low Atherosclerotic Risk Profile

Abstract

BACKGROUND: Studies in middle-age and older (masters) athletes with atherosclerotic risk factors for coronary artery disease report higher coronary artery calcium (CAC) scores compared with sedentary individuals. Few studies have assessed the prevalence of coronary artery disease in masters athletes with a low atherosclerotic risk profile. METHODS:We assessed 152 masters athletes 54.4±8.5 years of age (70% male) and 92 controls of similar age, sex, and low Framingham 10-year coronary artery disease risk scores with an echocardiogram, exercise stress test, computerized tomographic coronary angiogram, and cardiovascular magnetic resonance imaging with late gadolinium enhancement and a 24-hour Holter. Athletes had participated in endurance exercise for an average of 31±12.6 years. The majority (77%) were runners, with a median of 13 marathon runs per athlete. RESULTS:Most athletes (60%) and controls (63%) had a normal CAC score. Male athletes had a higher prevalence of atherosclerotic plaques of any luminal irregularity (44.3% versus 22.2%; P=0.009) compared with sedentary males, and only male athletes showed a CAC ≥300 Agatston units (11.3%) and a luminal stenosis ≥50% (7.5%). Male athletes demonstrated predominantly calcific plaques (72.7%), whereas sedentary males showed predominantly mixed morphology plaques (61.5%). The number of years of training was the only independent variable associated with increased risk of CAC >70th percentile for age or luminal stenosis ≥50% in male athletes (odds ratio, 1.08; 95% confidence interval, 1.01-1.15; P=0.016); 15 (14%) male athletes but none of the controls revealed late gadolinium enhancement on cardiovascular magnetic resonance imaging. Of these athletes, 7 had a pattern consistent with previous myocardial infarction, including 3(42%) with a luminal stenosis ≥50% in the corresponding artery. CONCLUSIONS:Most lifelong masters endurance athletes with a low atherosclerotic risk profile have normal CAC scores. Male athletes are more likely to have a CAC score >300 Agatston units or coronary plaques compared with sedentary males with a similar risk profile. The significance of these observations is uncertain, but the predominantly calcific morphology of the plaques in athletes indicates potentially different pathophysiological mechanisms for plaque formation in athletic versus sedentary men. Coronary plaques are more abundant in athletes, whereas their stable nature could mitigate the risk of plaque rupture and acute myocardial infarction. Prevalence of Subclinical Coronary Artery Disease in Masters Endurance Athletes With a Low Atherosclerotic Risk Profile© 2017 American Heart Association, Inc. ORIGINAL RESEARCH ARTICLE R egular exercise confers a low risk profile for atherosclerosis and is associated with a 50% reduction in adverse events from coronary artery disease (CAD).1,2 The amount of physical activity required to achieve these benefits is 150 minutes of moderate exercise per week. [3][4][5][6] In contrast, some athletes engage in several hours of intensive training p...

25-Year Physical Activity Trajectories and Development of Subclinical Coronary Artery Disease as Measured by Coronary Artery Calcium: The Coronary Artery Risk Development in Young Adults (CARDIA) Study

“…Along these lines, recent studies in healthy middle-age highly-active adults have reported that higher doses of exercise were associated with higher levels of CAC and that the atherosclerotic plaques were in fact likely to be more calcified plaques, suggesting that the stable nature of coronary plaques in highly active individuals may mitigate plaque rupture. 41,42 Additional research investigating whether higher PA levels, including type and duration of PA, are associated with increased plaque calcium density for a given CAC volume, indicative of plaque stability to evaluate CV risk, is needed. 43 …”

“…48 Earlier evidence has suggested that, physiologically, elite ultra-endurance athletes have increased diameter and dilation of the coronaries 45,50 partly due to adaptations of the vascular structure, and possibly an increase in the caliber and/or number of resistance arterioles. 50 So although there can be presence of increased atherosclerosis in endurance athletes compared with sedentary males with similar risk profile, 51 it may not necessarily translate into adverse clinical outcomes due to presence of enlarged coronary artery size and dilatory capacity. 52,53 Similarly, it is argued that risk of brady-arrhythmias and atrial fibrillation 54 is modest, give the coronaries of endurance athletes presumably have superior vasomotor reserve and reduced risk of plaque rupture leading to thrombosis.…”

Aspirin Use to Reduce the Risk of Sports-Related Cardiac Arrest in High-Risk Athletes

“…7 Targeted screening with coronary artery calcium scores in endurance athletes is prudent based on a higher prevalence of coronary plaque volume in the presence of low conventional cardiac risk-factor profiles. 8 Scores over 100 Agatston units, which independently identify a 10-year risk for incident cardiac events greater than 7.5%, justify additional measures for primary prevention by current guidelines. 9 A validated risk calculator incorporating coronary artery calcium scores might enhance predictive accuracy among athletes with positive findings below that threshold.…”

Aspirin to Prevent Sudden Cardiac Death in Athletes with High Coronary Artery Calcium Scores

“…11,12 Based on the increased prevalence of subclinical coronary artery disease demonstrated in masters endurance athletes with low conventional risk-factor profiles, coronary artery calcium scores are recommended over conventional calculators as an independent predictor of cardiac events to guide use of additional measures for primary prevention. [13][14][15][16] The inverse correlation of coronary artery plaque volume with short-term cardiac event-free survival, and documentation of coronary atherosclerosis as the cause of race-related sudden cardiac deaths even in the most experienced runners attest to the morbidity and mortality associated with what has been called by some "hearts of stone" of undetermined significance. [17][18][19][20][21][22][23] An explanation for increased coronary atherosclerosis in experienced endurance athletes compared with matched control persons is that inflammation during repetitive bouts of exertional rhabdomyolysis promotes calcification through recurrent injury to vascular endothelium.…”