Redefining the upper limits of ventricular volumes in elite athletes
Authors: Verwijs S M , Van Hattum J C , Daems J J N , Planken R N , Van Randen A , Boekholdt S M , Groenink M , Nederveen A J , Prakken N H J , Moen M H , Velthuis B K , Wilde A A M , Pinto Y M , Jorstad H T 
Published: October 2022

Abstract

Background/Introduction
Specific athlete reference values for cardiac volumes and function using cardiac magnetic resonance (CMR) parameters have been reported and are used in clinical practice. Elite athletes are conventionally thought to demonstrate the highest levels of physiological adaptation to sports and therefore dictate the upper limit of normal for biventricular size and function in the athlete population.

Purpose
To compare volumetric parameters in a cohort of both male and female elite-level athletes to previously published reference values.

Methods
We used data from the prospective ELITE-cohort, which collects pre-participation data of elite athletes (national-, international-, Olympic-, Paralympic-level), including CMR imaging. Athletes suspected of pathology based on comprehensively investigated electrocardiograph, exercise test, echocardiogram and late gadolinium enhancement were excluded. Biventricular volumes were derived from short-axis cine images using Cvi42 (v5.1.2.) and indexed for body surface area (BSA). Volumetric parameters were compared to the previously reported gender- and Mitchell sports classification specific cardiac 95th percentile (95%tile) reference values, as reported by Luijkx et al.: left-ventricle (LV) end-diastolic volume (EDV) / BSA for high-static and high-dynamic sports (HS/HD; ♀ 142 ♂ 158); low-static and high-dynamic (LS/HD; ♀ 127 ♂ 149); high-static and low-dynamic (HS/LD; ♀ 114 ♂ 140); right ventricle (RV) EDV / BSA HS/HD (♀ 154 ♂ 184), LS/HD (♀ 136 ♂ 163), and HS/LD (♀ 120 ♂ 157).

Results
We analysed a total of 221 athletes (38% female), with a median age (IQR) of 26.0 (22.5–29.8) years, and mean ±SD BSA of 1.96±0.22 m2. Athletes were classified according to the Mitchell sports classification: HS/HD 116 (54%); LS/HD 61 (29%); moderate-static and high-dynamic (MS/HD) 20 (9.4%); HS/LD 16 (7.5%) (Table). We found smaller mean ±SD (95%tile) RV EDV/BSA in athletes participating in HS/HD sports (♀: 117±20 (148) and ♂: 133±20 (160)) and LS/HD sports (♀: 109±11 (129) and ♂: 119±15 (142)) and smaller LV EDV/BSA in male athletes in LS/HD sports (116±15 (138)) compared to reference values, (Figure). When using conventional cut-offs in our population we found 10 (4.5%) and 2 (0.9%) athletes above 95%tile for LVEDV/BSA and RVEDV/BSA, respectively (Figure).

Conclusion
In a cohort consisting of healthy, elite athletes, volumetric adaptations were less outspoken as compared with current reference ranges, specifically in the RV. Only 1 percent of our athletes exceeded conventional 95%tile references for the RV. Potentially, current athlete reference values could overestimate healthy upper limits of cardiac volumes in elite athletes. Our study could indicate that a stricter definition of volumetric reference values, including 95%tile, might be of added value in the specific group of elite athletes to help differentiate between pathology and sports adaptation.

Funding Acknowledgement
Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Amsterdam Movement Sciences (P1A210AMC2018)