Sudden cardiac death related to physical exercise and sports in the young: a nationwide cohort study of Australia

Funding Acknowledgements

Type of funding sources: None.

Background

Sudden cardiac death (SCD) during physical exercise is uncommon but devastating.

Purpose

We aimed to determine risk factors, causes and circumstances of sports and exercise-related SCD in the young in Australia.

Methods

We retrospectively reviewed the National Coronial Information System (NCIS) registry for deaths in Australia relating to cardiovascular disease (CVD) in cases aged 10 to 35 years between 2000-2016. Included cases had been undertaking sports or physical exercise at time of event. We collected baseline demographics and circumstances of death including location, type of physical exercise, whether the event was witnessed, and engagement of bystander cardiopulmonary resuscitation (CPR) and automated external defibrillator (AED) use prior to ambulance arrival.

Results

Over a 17-year period, 1,925 SCD cases were identified of which 110 cases (6%) related to sports/physical exercise were included in final analysis. Median age was 27 years (interquartile range [IQR] 21-32 years) with most being male (92%). Median BMI was 27 kg/m2 (IQR, 23-30) with 13 cases (12%) occurring in active athletes. Most common causes were coronary artery disease (CAD; 37%) and sudden arrhythmic death syndrome (SADS; 20%). Australian Rules Football (24%), running/jogging (14%) and soccer (14%) were the most frequently practiced at time of event. Prior symptoms were present in 39% (chest pain 37%, presyncope/syncope 26%). Most were witnessed (87%) with bystander CPR in 70%. AED use prior to ambulance arrival was 8%.

Conclusions

This study demonstrates the high occurrence of CAD and SADS in exercise-related SCD in the young. Although events were commonly witnessed, an AED was seldom used prior to ambulance arrival highlighting an important opportunity to improve outcomes in the post-arrest chain of survival.

Confirming a beneficial effect of the six-minute walk test on exercise confidence in patients with heart failure

Background:

Low confidence to exercise is a barrier to engaging in exercise in heart failure patients. Participating in low to moderate intensity exercise, such as the six-minute walk test, may increase exercise confidence.

Aim:

To compare the effects of a six-minute walk test with an educational control condition on exercise confidence in heart failure patients.

Methods:

This was a prospective, quasi-experimental design whereby consecutive adult patients attending an out-patient heart failure clinic completed the Exercise Confidence Scale prior to and following involvement in the six-minute walk test or an educational control condition.

Results:

Using a matched pairs, mixed model design ( n=60; 87% male; Mage=58.87±13.16), we identified a significantly greater improvement in Total exercise confidence ( F(1,54)=4.63, p=0.036, partial η2=0.079) and Running confidence ( F(1,57)=4.21, p=0. 045, partial η2=0.069) following the six-minute walk test compared to the educational control condition. These benefits were also observed after adjustment for age, gender, functional class and depression.

Conclusion:

Heart failure patients who completed a six-minute walk test reported greater improvement in exercise confidence than those who read an educational booklet for 10 min. The findings suggest that the six-minute walk test may be used as a clinical tool to improve exercise confidence. Future research should test these results under randomized conditions and examine whether improvements in exercise confidence translate to greater engagement in exercise behavior.

P574Accuracy of wrist-worn heart rate monitors for chronotropic assessment in atrial fibrillation

Introduction

Wrist-worn fitness and heart rate (HR) monitors are increasingly popular. Previous studies in healthy participants with sinus rhythm (SR) have yielded variable results depending on HR, activity levels and device tested. A paucity of data exists on their accuracy in atrial fibrillation (AF) in ambulatory patients.

Purpose

We sought to assess the HR accuracy of 2 commercially available smart watches (Fitbit Charge HR [FB] and Apple Watch Series 3 [AW]) compared with Holter monitoring in an ambulant patient cohort.

Methods

Patients aged >18 years referred for 24-hour Holter monitoring were prospectively recruited. The Holter monitor was the criterion measure. Each patient was randomly allocated to either a FB or AW along with their Holter monitor. The study protocol was approved by the institutional review board.

Statistical analysis: Pearson (r) correlation coefficients and Bland-Altman comparison with 95% limits of agreement (LoA) were evaluated to assess criterion validity and agreement between the smart watch and Holter ECG-HR. Bias was the calculated mean difference between the smart watch and ECG-HR. A ± 10-beat different between Holter-HR and SW-HR was used as a clinically relevant range to establish the accuracy of HR estimation by SW.

Results

Across all devices, 53,288 hear rate values were recorded from 32 patients. Twenty six patients were in persistent AF and six were in SR. Twelve patients wore the FB while 20 wore the AW. In the FB arm, nice patient were in persistent AF and three in SR. In the AW arm, persistent AF was the rhythm in seventeen and SR in three. Patients in SR demonstrated overall strong agreement compared to Holter monitoring (Mean Bias <1 beat, LoA −11 to 11 beats) and a correlation coefficient of 0.87 (p<0.001). In AF, both devices underestimated HR measurements (Overall Bias −9 beats, LoA −41 to 23, r=0.60, p<0.001). The AW had lower bias and narrower LoA compared to FB (−5 beats vs −13 beats, LoA −31 to 21 beats vs −50 to 22 beats). Using a ± 10-beat range against ECG-HR for clinical accuracy, both the AW and FB performed satisfactorily in SR with 95.2% of AW and 92.2% of FB HR readings considered valid. In AF, however, the AW-HR readings were within the ± 10-beat threshold in 76.5% of the time compared with only 56.1% of FB readings.

Conclusion

In ambulatory patients, smart watches were accurate in HR estimation when compared to Holter monitor in SR; however tended to underestimate HR in AF. Further improvements in device technology are needed before the widespread consumer adoption of this nascent technology for chronotropic assessment in arrhythmias.

Congenital auricular deformity consisting of cleft concha and transposition of the earlobe and antitragus

We have reported a patient with a congenital auricular deformity consisting of cleft concha transposition of the earlobe and antitragus. This is an extremely rare entity. We have named it congenital auricular deformity consisting of cleft concha and transposition of the earlobe and antitragus because the case we described is a congenital cleft auricle and transposition of the earlobe and antitragus in terms of position of the deformity.