Diagnostic yield of cardiac magnetic resonance in athletes with and without features of the athlete's heart and suspected structural heart disease

Abstract

Abstract Background Cardiac magnetic resonance (CMR) is a second-line imaging test in cardiology. Balanced enlargement of heart chambers called athlete's heart (AH) is a part of physiological adaptation to regular physical activity. Purpose The aim of the study was to evaluate the diagnostic utility of CMR in athletes with suspected structural heart disease (SHD) and to analyse the relation between the presences of AH and SHD. Methods This retrospective, single centre study included consecutive 154 athletes (57 non-amateur, all sports categories, 87% male, mean age 34±12 years) referred for CMR because of suspected SHD. The suspicion was based on existing guidelines including electrocardiographic and/or echocardiographic changes suggestive of abnormality but without a formal diagnosis. AH was defined as a balanced enlargement of most heart chambers above the reference values in adults with or without mild left ventricular hypertrophy. Results CMR permitted to establish a new diagnosis in 66 patients (42%). The main diagnoses included myocardial fibrosis typical for prior myocarditis (n=21), hypertrophic cardiomyopathy (n=17, including 6 apical forms), other cardiomyopathies (n=10) and prior myocardial infarction (n=6). The presence of pathologic LGE was found in 41 patients (27%) and was non-significantly higher in athletes without AH (32% vs. 19%, p=0.08). Junction-point LGE was more prevalent in patients with AH phenotype (22% vs. 9%, p=0.02). Patients without AH tended to be more likely diagnosed with an SHD than those with AH (49% vs. 32%, p=0.05). This was mainly caused by a trend towards a higher prevalence of non-apical hypertrophic cardiomyopathy and prior myocardial infarction in this group. Conclusions The inclusion of CMR into the diagnostic process leads to a new diagnosis in many athletes with suspicion of SHD and equivocal routine tests. Athletes with AH pattern are equally likely to be diagnosed with SHD in comparison to those without AH phenotype. It shows that the development of AH and SHD can occur in parallel, which makes differential diagnosis in this group of patients more challenging. Funding Acknowledgement Type of funding sources: None.