8 Defining the normal spectrum of electrocardiographic and structural adaptations of white, black and mixed-race adolescent athletes' heart. (December 2018)

• Record Type: Journal Article
• Authors: Malhotra, Aneil; Sharma, Sanjay
• Is Part Of: Postgraduate medical journal. Volume 94(2018)Supplement 1
• Page Start: A8
• Page End: A9
• Publication Date: 2018-12
• Subjects: Medicine -- Periodicals; 610
• DOI: 10.1136/postgradmedj-2018-fpm.19
• Languages: English
• ISSNs: 0032-5473

Abstract

Abstract : Introduction: This study aimed to describe the normal spectrum of EKG changes and left ventricular dimensions in a large cohort of healthy white, black and mixed-race, male and female adolescent soccer players. There are a paucity of data describing the adolescent athlete's heart with the vast majority of studies based on adult white athletes. Not only are adolescent athletes (aged 14–18 years old) significantly understudied compared with adults but are more vulnerable to sudden cardiac death than adults. There is a four to six-fold higher incidence of sudden cardiac death (SCD) during exercise among young black athletes (aged 14–35 years) compared with young white athletes. Such a significant disparity has never before been systematically explored, due to the limitations in identifying individuals at risk and a consequent lack of a well-defined population. The population of black individuals in the UK is 8 million, making up 13% of the overall population. In professional sport however, black athletes constitute up to 30% of all sportsmen and sportswomen. Moreover, the mixed-race athlete's EKG and echocardiogram has not before been described, though this is the fastest growing ethnic group participating in sport in the UK and US and for whom no such previous data exist. Methods: Between 1996 and 2016, 11 435 consecutive adolescent soccer players underwent pre-participation screening. 11 168 soccer players (mean age 16.4±1.3 years) were evaluated with an EKG and echocardiogram measuring maximal left ventricular wall thickness (MLVWT) and left ventricular end diastolic diameter (LVEDD). Ethnicity was self-reported in accordance with UK census classification. Results: The cohort included 10 581 (95%) males and 587 (5%) females. There were 9664 (87%) white, 1004 (9%) black and 500 (4%) mixed-race athletes. Black male athletes exhibited a greater MLVWT compared with both white (10.9 vs. 10.6 mm; p=0.0323). (Figure 1 ). White male athletes demonstrated the largest LV cavity sizes compared with black athletes (52.4 vs. 50.6 mm; p=0.0477). Black female athletes revealed a greater MLVWT compared with white female athletes (8.6 vs. 8.2 mm; p=0.0352). As with males, white female athletes demonstrated larger LV cavity sizes than black athletes (46.3 vs. 45.2 mm; p=0.0088) and mixed-race athletes (46.3 vs. 45.4 mm; p=0.0316). For white males, a proposed upper limit for MLVWT is 13 mm and for black and mixed-race males<14 mm. For females of all three ethnic groups this cut off is <11 mm. Proposed upper limits for maximal LVEDD for white male is <60 mm and for black and mixed-race males<59 mm. For all females the cut-off is <52 mm. Conclusions: Black athletes of both sexes reveal the greatest wall thickness compared with mixedrace and white athletes. Conversely, white athletes display the largest cavity size in both sexes. Mixed-race athletes demonstrate electrocardiogram and echocardiogram features more similar to black athletes than white athletes. Information regarding the upper limits of normality in this age group is useful in enabling the differentiation between physiological adaptation and cardiomyopathy.