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Differentiation between athlete's heart and dilated cardiomyopathy in athletic individuals
Lynne Martina Millar1, Zephryn Fanton1, Gherardo Finocchiaro1
1Cardiology Clinical Academic Group, St. George's University Hospitals NHS Foundation Trust and Institute of Molecular and Clinical Sciences, St. George's, University of London, London, UK.
Insights
Differentiating early dilated cardiomyopathy (DCM) from athlete heart requires careful assessment. Exercise stress echocardiography effectively distinguishes between the two by evaluating left ventricular ejection fraction changes during exercise.
Area of Science:
- Cardiology
- Sports Cardiology
- Cardiovascular Imaging
Background:
- Distinguishing early dilated cardiomyopathy (DCM) from physiological left ventricular (LV) dilatation in athletes presents a diagnostic challenge.
- The 'grey zone' of athletes with LV dilatation and reduced ejection fraction requires accurate differentiation from pathological conditions.
Purpose of the Study:
- To evaluate the role of a cascade of investigations in differentiating early DCM from physiological LV dilatation in athletes.
- To identify key diagnostic markers for distinguishing between these two entities.
Main Methods:
- A cohort of asymptomatic males with DCM, 'grey zone' athletes, and normal athletes underwent NT-proBNP measurement, ECG, and exercise echocardiography.
- Grey-zone athletes and DCM patients also underwent cardiovascular magnetic resonance (CMR) and Holter monitoring.
Main Results:
- Grey-zone athletes showed larger LV cavity dimensions and lower LV ejection fraction compared to controls, but lacked abnormal NT-proBNP, complex arrhythmias, or late gadolinium enhancement on CMR.
- Exercise echocardiography revealed significant differences: 96% of grey-zone athletes increased LV ejection fraction by >11% versus 23% of DCM patients.
- Failure to increase LV ejection fraction >11% or achieve peak LV ejection fraction >63% during exercise strongly predicted DCM.
Conclusions:
- A comprehensive cascade of routine investigations, particularly exercise stress echocardiography, is highly valuable in differentiating grey-zone athletes from asymptomatic DCM patients.
- Exercise-induced changes in LV ejection fraction are critical for distinguishing physiological adaptation from pathological remodeling.
Objective:
Distinguishing early dilated cardiomyopathy (DCM) from physiological left ventricular (LV) dilatation with LV ejection fraction <55% in athletes (grey zone) is challenging. We evaluated the role of a cascade of investigations to differentiate these two entities.
Methods:
Thirty-five asymptomatic active males with DCM, 25 male athletes in the 'grey zone' and 24 male athletes with normal LV ejection fraction underwent N-terminal pro-brain natriuretic peptide (NT-proBNP) measurement, ECG and exercise echocardiography. Grey-zone athletes and patients with DCM underwent cardiovascular magnetic resonance (CMR) and Holter monitoring.
Results:
Larger LV cavity dimensions and lower LV ejection fraction were the only differences between grey-zone and control athletes. None of the grey-zone athletes had abnormal NT-proBNP, increased ectopic burden/complex arrhythmias or pathological late gadolinium enhancement on CMR. These features were also absent in 71%, 71% and 50% of patients with DCM, respectively. 95% of grey-zone athletes and 60% of patients with DCM had normal ECG. During exercise echocardiography, 96% grey-zone athletes increased LV ejection fraction by >11% from baseline to peak exercise compared with 23% of patients with DCM (p<0.0001). Peak LV ejection fraction was >63% in 92% grey-zone athletes compared with 17% patients with DCM (p<0.0001). Failure to increase LV ejection fraction >11% from baseline to peak exercise or achieve a peak LV ejection fraction >63% had sensitivity of 77% and 83%, respectively, and specificity of 96% and 92%, respectively, for predicting DCM.
Conclusion:
Comprehensive assessment using a cascade of routine investigations revealed that exercise stress echocardiography has the greatest discriminatory value in differentiating between grey-zone athletes and asymptomatic patients with DCM. Our findings require validation in larger studies.
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