John Orchard’s research while affiliated with The University of Sydney and other places

Background: Smartphone electrocardiograms (iECGs) are an innovative method of capturing transient arrhythmias which are occasionally experienced by athletes. This study aimed to assess the accuracy of a 6-lead iECG compared with 12-lead ECG in athletes and those with known genetic heart disease (positive controls). Research design and methods: Each participant had a resting 12-lead ECG (supine) and a 30 second 6-lead iECG (seated) taken within 2 hours. Manual measurements of heart rate, QTc and PR intervals, and QRS duration were completed using digital calipers. Bland-Altman analysis was used to assess the quantitative agreement of measurements. Results: The 6-lead readings for heart rate were faster than the 12-lead in athletes (n = 233) and positive controls (n = 49). All other measurements were shorter in the 6-lead. QTc mean difference was smaller in the positive controls (4.7 ± 26.0 ms) than in athletes (12.5 ± 25.0 ms). The largest difference was in PR intervals, both in athletes (12.8 ± 17.7 ms) and positive controls (7.6 ± 18.9 ms). QRS duration had the smallest mean difference (0.6 ± 9.0 ms in athletes, 1.0 ± 12.7 ms in positive controls). Conclusions: The 6-lead readings had reasonable agreement with the 12-lead ECG. A 6-lead iECG is a reasonable option to opportunistically capture arrhythmias that may occur infrequently, but should not replace a 12-lead if available.

Introduction: Traditional monitoring of athletes with cardiac symptoms is limited due to sport-specific considerations and the intermittent nature of symptoms. Some portable electrocardiogram (ECG) devices may have more diagnostic utility than traditional monitoring. Their accuracy, advantages, and limitations should be considered when a clinician is considering the most appropriate device for investigation of an athlete's symptoms. Areas covered: There are six main categories of portable ECG devices: smartwatches, handheld devices, mobile cardiac telemetry (MCT), patches, rings, and chest sensors. The aim of this review is to highlight to a clinician the potential benefits of some devices over others to assist the physician in identifying the most appropriate device. We present peer-reviewed literature on the accuracy of each type of device along with advantages and limitations. Expert opinion: For a user-initiated capture of an ECG, smartwatches and handheld devices are easy to use and supported by peer-reviewed literature. Rings can also provide a user-initiated ECG, though there is limited evidence to support their usage. For continuous monitoring, patches and MCT are both useful, though there is limited access to these devices. Chest sensors show some promise, although access is currently limited in some countries.

Objective: i) determine whether the grade of hamstring strain confirmed by magnetic resonance imaging (MRI) is related to time to return to play, and ii) describe the incidence, prevalence and grade of hamstring strains confirmed by MRI in elite Australian cricket players. Design: Retrospective case series. Methods: Hamstring strains from professional domestic and international cricket teams over 13.5 seasons which had received MRI scans were graded using British Athletics Muscle Injury Classification (BAMIC) system. The main outcome measure was time to return to play. Results: 141 hamstring strain injuries with available MRI imaging scans were recorded during the study period (average 3.2 per 100 players per season: male 4.5, female 1.2). The most commonly injured muscle was biceps femoris (64%, 95% CI 56-71%) and the most frequent category of injury was grade 2C (27%, 20-35%). Across all injury grades, players were unavailable for full participation for a median of 23 (IQR 15-38) days and missed 3 (1-6) matches. The number of days unavailable were higher for injuries which were graded 2 or 3, compared to grade 1 (p=0.018, p=0.002 respectively), and injuries which included the tendon compared to those which did not (p=0.002). Conclusions: This study provides evidence that higher grade injuries and those involving the intramuscular tendon are associated with a more prolonged return to play. This finding should be viewed in context of the study limitation that clinicians treating players were not blinded to the MRI findings.

Introduction Athletes occasionally experience transient arrythmias that are difficult to capture using traditional methods. Smartphone electrocardiogram (ECG) technology presents an innovative method of capturing transient arrythmias. A 6-lead (6L) smartphone device that measures leads I, II, III, aVR, aVL, and aVF, has been shown to be accurate in some populations but has limited evidence in athletes. A previous pilot study comparing 6L with 12L readings in athletes showed good correlations. Purpose To assess the accuracy of the 6L device in athletes by comparing the 6L with a 12-lead (12L) ECG in a larger sample size under real-world conditions. Methods From 2020-2023, athletes (n=217, mean age 18.0±3.8 years, 40% female) had a resting supine 12L ECG as part of cardiac screening and a seated 30s 6L reading within 2 hours of the 12L. Manual measurements of RR, QT, PR intervals, and QRS duration in the 6L and 12L ECGs were completed by a cardiologist using EPS Digital Calipers in lead II. A subset (n=30) was measured by 4 expert cardiologists and the mean was taken. Each measurement was calculated as an average of at least 6 consecutive beats in the 6L and 12L. Bland-Altman analysis was used to assess the quantitative agreement between heart rate (HR), QTc interval (Bazett), PR interval and QRS duration in the 6L and 12L. ECGs were analysed for agreement of QRS axis (normal, left and right axis deviation defined by the International Criteria for Athlete ECG Interpretation[1]). Results The 6L readings for HR were 5.0±11.0bpm faster than the 12L; 6L readings for other measurements were shorter than the 12L. QTc had the largest difference, with the 6L on average 14.2±27.4ms shorter than the 12L reading. For QTc, 5.5% of readings were >60ms different, mostly due to baseline interference in the 6L traces. PR intervals were 13.9±16.3ms shorter in the 6L than the 12L. QRS duration measurements were similar, with 6L readings being 0.8±10.2ms shorter than the 12L reading. There was 96.8% agreement on QRS axis classification between 6L and 12L. Conclusion The 6L readings had fair agreement with the 12L ECG, although the standard deviations were higher than measured in the pilot study, suggesting less consistent accuracy of the 6L. Most 6L measures (excluding HR) were slightly shorter than the 12L, consistent with studies in other populations. QRS axis categories were very similar. Given the change from supine to seated, it is unsurprising that HR was higher in the 6L. Our previous work showed good correlation between 6L and 12L readings and excellent utility of the portable 6L device for detecting transient arrhythmias in athletes. This larger study confirms most of those findings but adds caution that baseline interference is not uncommon in real-world 6L readings, meaning that QTc may be difficult to accurately measure.

Introduction: Western Pacific nations have experienced lower excess mortality compared to rest of the world since 2020 and recently performed exceptionally well on the medal tally at the 2024 Paris Olympics. This study aimed to analyse any possible connection between these factors. Methods: The top performing 18 nations from 2012, 2016 and 2020 Olympics (after Russia and Ukraine were excluded) had their relative Gold medals, total medals and medal points (Gold =3, Silver=2, Bronze=1) for Paris 2024 analysed using a backward stepwise linear regression model. Initial input factors included previous medal tallies, home city advantage, time zone effects, national excess deaths 2020-2023, average GDP growth 2020-2023 and number of country signatories to the Great Barrington Declaration (GBD), with factors >P=0.10 removed sequentially. Results: Total medals were best predicted by previous total medals (t=21.0, P<0.001) and home city advantage (t=4.1, P<0.001). Gold medals were best predicted by previous Gold medals (t=10.3, P<0.001), low national excess deaths (t=-3.2, P<0.007) and low signatories to the GBD (t=-2.2, P<0.05). Medal points were best predicted by previous medal points (t=18.1, P<0.001), home city advantage (t=3.2, P<0.007) and low national excess deaths (t=-1.8, P<0.09). Discussion: The Western Pacific countries with a COVID-cautious national perspective (Australia, China, Japan, New Zealand, South Korea) tended to win more Gold medals than expected in Paris, compared to countries with a COVID-stoical national perspective (e.g. Great Britain, United States) which won fewer Golds than expected. This suggests that a COVID-cautious mentality may have contributed to better performance than a COVID-stoical approach. It is unclear whether any mechanism was physiological (less infectious disease impact before or during the Olympics) or psychological. If this effect existed for Golds, it did not appear to have any effect on Silver and Bronze medals.

Background Cardiac screening of elite athletes is widely recommended by Australasian sporting federations, but data are not structured to be shared. Data are lacking from underrepresented groups to inform ECG interpretation guidelines. The ARENA (Australasian Registry of Screening ECGs in National Athletes) project is a retrospective and prospective, multicenter, longitudinal, observational registry of athlete cardiac screening results and outcomes. The aim is to create a repository to improve our understanding of the diagnoses and outcomes of screening. Methods Participating sports that conduct cardiac screening of athletes will contribute data. This includes an initial collection (retrospective data, waiver of consent) and future prospective data (opt‐out consent). Data include sex, age, sport/event, screening date, ECG findings, cardiac test results, follow‐up details, sport participation status, cardiac diagnoses, and major cardiovascular outcomes defined as sudden cardiac arrest/death, cardiac syncope or implanted cardioverter defibrillator shock, cardiac hospitalization, and arrhythmias requiring intervention. Comparisons will be made between diagnoses, outcomes, and ECG features and analyzed by sport and sex. The ARENA project was developed in collaboration with sporting bodies, team physicians, and players association representatives and endorsed by the Australasian College of Sport & Exercise Physicians and Sports Medicine Australia. Conclusions The ARENA project will provide a long‐term international data repository to improve our understanding of ECG interpretation, cardiac screening and diagnoses, and the prevalence of cardiovascular outcomes in screened athletes. A unique aim is to address evidence gaps in underrepresented athlete groups, specifically female athletes and Indigenous populations. Results will inform screening policies and guidelines.

Background Sports medicine (injury and illnesses) requires distinct coding systems because the International Classification of Diseases is insufficient for sports medicine coding. The Orchard Sports Injury and Illness Classification System (OSIICS) is one of two sports medicine coding systems recommended by the International Olympic Committee. Regular updates of coding systems are required. Methods For Version 15, updates for mental health conditions in athletes, sports cardiology, concussion sub-types, infectious diseases, and skin and eye conditions were considered particularly important. Results Recommended codes were added from a recent International Olympic Committee consensus statement on mental health conditions in athletes. Two landmark sports cardiology papers were used to update a more comprehensive list of sports cardiology codes. Rugby union protocols on head injury assessment were used to create additional concussion codes. Conclusion It is planned that OSIICS Version 15 will be translated into multiple new languages in a timely fashion to facilitate international accessibility. The large number of recently published sport-specific and discipline-specific consensus statements on athlete surveillance warrant regular updating of OSIICS.

Background/Introduction Cardiac screening of competitive athletes for conditions associated with sudden cardiac death is recommended by bodies including the European Society of Cardiology. High Performance Sport New Zealand (HPSNZ) commenced cardiac screening of elite Olympic sport athletes in 2012. Purpose To report the 10 year outcomes and findings of the HPSNZ cardiac screening program, including comparisons of electrocardiogram (ECG) features between sexes, sports and ethnicities. Methods Athletes were screened by HPSNZ from February 2012-June 2022 in accordance with HPSNZ protocols and as required by their International Federations. Screening included a personal/family history, physical examination and resting 12-lead ECG (interpreted by a cardiologist experienced in athlete ECGs), and athletes were followed for up to 11 years. Clinical findings and ECGs were managed contemporaneously as required. In July 2022 all screening records, including demographic data, ECGs, follow-up testing and diagnoses were reviewed. Although ECG guidelines changed during the period, any abnormal/equivocal ECGs were re-reviewed using the International Criteria. Comparisons between groups were performed using Fisher’s exact test (2-sided, p<0.05 considered significant). Results 2075 ECGs from 1189 athletes (53% female, mean age 21 years; 83% European, 14% Māori and Pacific Islander, 3% other ethnicities) were included. Major diagnoses included Wolff-Parkinson-White (WPW) syndrome (0.7%) and cardiomyopathies (0.3%). Overall, 3.5% of ECGs were abnormal (International Criteria). ECGs of female athletes were more frequently abnormal (4.4% vs 2.5%, p=0.02) and had more abnormal T-wave inversion (TWI) (3.1% vs 0.9%, p=0.0005) compared to males. 47% of the abnormal TWI in females was limited to V1-V3 with no other ECG abnormalities. There were no differences in the proportion of abnormal ECGs between the highest intensity/endurance sports and other sports, nor between Māori and Pacific Island athlete ECGs compared with European (Table 1). No athletes retired for cardiac reasons, there were no cardiac deaths nor major cardiac incidents during the period (mean follow up from first screening: 73 months). There was a significant reduction in follow-up tests recommended after the introduction of the International Criteria. Conclusions WPW was the most frequent diagnosis, with very little cardiomyopathy found in this cohort. The proportion of abnormal ECGs was low overall, and lowest after the introduction of the most recent athlete ECG guidelines, likely reflecting enhanced specificity. ECGs of female athletes were more frequently abnormal, predominantly because of anterior TWI V1-V3, which potentially could be considered a normal finding in elite female athletes. We report for the first time a comparison between Māori/Pacific Island athletes and European athletes, showing no difference in the proportion of abnormal ECGs, although further data are needed.