Correlation between ECG abnormalities and cardiac parameters in highly trained asymptomatic male endurance athletes: evaluation using cardiac magnetic resonance imaging

Abstract

Intensive endurance training can induce abnormal ECG patterns at rest. These alterations are differentiated into minor, mildly or distinctly abnormal ECG patterns. Echocardiographic data imply a correlation between the extent of these alterations and cardiac parameters like cardiac volume or wall thickness. In comparison to echocardiography, cardiac magnetic resonance imaging (MRI) is characterized by high reproducibility and accuracy. The aim of this study was to investigate the correlation between ECG alterations and cardiac parameters in highly trained asymptomatic male endurance athletes as assessed using cardiac MRI. Forty-five asymptomatic male endurance athletes (mean age 40 ± 8.9 years., range 19-59 years., 13 ± 5 h of training per week) underwent a cardiac MRI examination in addition to a resting ECG. Based on the ECG patterns at rest, the athletes were divided into groups with normal or minor (group 1) and mild or distinct (group 2) alterations. Steady-state free-precession cine MRI was used to calculate left and right ventricular end-diastolic volume, end-systolic volume, stroke volume, ejection fraction, and myocardial mass (MM). Late enhancement imaging was used to exclude structural alterations or myocardial scarring. Athletes in group 1 and 2 did not differ significantly in terms of age, height, body weight, body mass index or hours of training per week. Athletes with mildly or distinctly abnormal ECG patterns showed a significantly higher MM than athletes with minor ECG alterations at rest or normal resting ECG values (156.4 ± 18.4 g vs. 140.5 ± 20.0 g; p = 0.0103). The differences persisted when the values were corrected for body surface area (80.0 ± 7.4 g/m² vs. 73.4 ± 8.3 g; p = 0.0093). All other assessed cardiac parameters did not differ between the two groups. Pathological myocardial enhancement was detected only in one patient with a minor abnormal ECG. Male asymptomatic endurance athletes with mildly or distinctly abnormal ECG patterns at rest are characterized by a higher myocardial mass than comparable athletes with minor alterations or normal ECG at rest. Thus, the extent of ECG-abnormalities seems to be mainly the result of an increase in myocardial mass. Additionally, the absence of mild or distinct ECG alterations does not exclude the presence of pathological late gadolinium enhancement.

Right and Left Ventricular Function and Mass in Male Elite Master Athletes

“…Studies evaluating the clinical impact of long-term intensive endurance training and competition in high-level elite master athletes are rare. [17][18][19][20] In addition, information about training volume (hours per week) and history (years) are often lacking, and cardiopulmonary exercise testing with quantification of the aerobic capacity by measuring maximal oxygen uptake (Vo 2 max) and power output for an assessment of sport-specific performance in professional elite endurance athletes with a long training history have not been performed so far. [17][18][19] Therefore, the aim of this study was to examine the cardiac structure and function with special emphasis on the RV by contrast-enhanced cardiovascular magnetic resonance (CMR) and complementary echocardiographic tissue Doppler imaging and strain data in long-term active, elite endurance master athletes including world class athletes.…”

Body surface area determined by whole‐body CT scanning: need for new formulae?

“…Even left atrial volume index has been shown and used as an important prognosticator, for example in dialysis patients (Ozdogan et al, 2010). A more recent interest has developed in sports medicine for comparison of different types of training and athletes regarding cardiac and left ventricular performance assessed by normalized cardiac output and left ventricular volumes (Erz et al, 2013). But obviously, the normalization may be complicated by extreme BSA values in this population, as recently discussed in a study on cardiac morbidity in obese patients (Adler et al, 2013), where the authors conclude that 'cardiac and stroke indices can be misleading relative to the underlying raw values as a result of distortion by widely used BSA formulae'.…”

Myocardial Fibrosis in Athletes

“…3 It is generally accepted that exercise benefits cardiovascular health, 4 but myocardial fibrosis (MF) has been detected in endurance athletes by cardiac magnetic resonance imaging (CMR) using late gadolinium enhancement (LGE). [5][6][7][8][9][10][11] Myocardial fibrosis is defined by a significant increase in the collagen volume of myocardial tissue. It is a complex process that involves all components of the myocardial tissue and can be triggered by tissue injury from myocardial ischemia (hypoxia), inflammation, and hypertensive overload.…”