Date Published: February 14, 2019
Publisher: Public Library of Science
Author(s): Csilla Czimbalmos, Ibolya Csecs, Attila Toth, Orsolya Kiss, Ferenc Imre Suhai, Nora Sydo, Zsofia Dohy, Astrid Apor, Bela Merkely, Hajnalka Vago, Aldrin V. Gomes.
We aimed to characterize gender specific left ventricular hypertrophy using a novel, accurate and less time demanding cardiac magnetic resonance (CMR) quantification method to differentiate physiological hypertrophy and hypertrophic cardiomyopathy based on a large population of highly trained athletes and hypertrophic cardiomyopathy patients.
Elite athletes (n = 150,>18 training hours/week), HCM patients (n = 194) and athletes with hypertrophic cardiomyopathy (n = 10) were examined by CMR. CMR based sport indices such as maximal end-diastolic wall thickness to left ventricular end-diastolic volume index ratio (EDWT/LVEDVi) and left ventricular mass to left ventricular end-diastolic volume ratio (LVM/LVEDV) were calculated, established using both conventional and threshold-based quantification method.
Whereas 47.5% of male athletes, only 4.1% of female athletes were in the grey zone of hypertrophy (EDWT 13-16mm). EDWT/LVEDVi discriminated between physiological and pathological left ventricular hypertrophy with excellent diagnostic accuracy (AUCCQ:0.998, AUCTQ:0.999). Cut-off value for LVM/LVEDVCQ<0.82 mm×m2/ml and for EDWT/LVEDViTQ<1.27 discriminated between physiological and pathological left ventricular hypertrophy with a sensitivity of 77.8% and 89.2%, a specificity of 86.7% and 91.3%, respectively. LVM/LVEDV evaluated using threshold-based quantification performed significantly better than conventional quantification even in the male subgroup with EDWT between 13-16mm (p<0.001). Almost 50% of male highly trained athletes can reach EDWT of 13 mm. CMR based sport indices provide an important tool to distinguish hypertrophic cardiomyopathy from athlete’s heart, especially in highly trained athletes in the grey zone of hypertrophy.
Regular and intensive physical training triggers structural and functional changes of the heart, including increased left ventricular wall thickness and cardiac mass, contributing to a clinical challenge of differentiating between athlete’s heart and hypertrophic cardiomyopathy (HCM) [1–3]. Relevance of this question arises from the fact that HCM is one of the most common causes of sudden unexpected cardiac death in young competitive athletes [4, 5]. Furthermore, false positive diagnosis of HCM may lead to unnecessary interruption of a professional sporting career.
Although numerous studies have investigated the morphologic cardiac adaptation of elite athletes, we have only limited published data providing CMR based cut-off values to differentiate athlete’s heart and HCM [12, 21]. To the best of our knowledge, this study is the first to report CMR based sport indices for differentiate athlete’s heart and HCM based on a large highly trained elite athlete population applying both conventional and threshold-based quantification methods.
This study highlights that elite healthy male athletes with very intensive and regular training may reach the grey zone of hypertrophy in almost 50%, which may cause diagnostic challenge in the clinical routine. However, only 4.1% of highly trained female athletes reach EDWT of 13 mm. CMR based sport indices provide an important tool to diagnose HCM and distinguish it from athlete’s heart. Not only EDWT/LVEDViCQ but also our new indices determined using TQ (EDWT/LVEDViTQ and LVMTQ/LVEDViTQ) showed high diagnostic accuracy both in the whole patient population and in the male subgroup with EDWT 13–16 mm. In all of our athletes with HCM, the only parameter falling into the pathological range was the LVMTQ/LVEDVTQ ratio.