The diagnostic accuracy of myocardial perfusion scintigraphy in athletes with abnormal exercise test results

Background Previous studies revealed a relatively high prevalence of electrocardiographic findings indicative for myocardial ischemia in asymptomatic athletes undergoing pre-participation screening. Myocardial perfusion scintigraphy is generally considered a valuable diagnostic and prognostic modality and often used for further diagnostic evaluation in these subjects. However, data on the diagnostic accuracy of myocardial perfusion scintigraphy in athletes are scarce. Objectives The main purpose of this study was to investigate the positive predictive value of myocardial perfusion scintigraphy for detection of coronary artery disease in asymptomatic athletes with abnormal exercise testing results during pre-participation screening. The secondary aim was to evaluate the prognostic value of myocardial perfusion scintigraphy. Methods Electronic charts of asymptomatic athletes who underwent myocardial perfusion scintigraphy following an abnormal exercise testing were retrospectively reviewed. Myocardial perfusion scintigraphy and exercise testing studies were revised. Athlete characteristics and cardiovascular risk factors were evaluated. Results One hundred and forty-three athletes were included. 29 athletes (20%) showed concordant abnormal exercise testing and myocardial perfusion scintigraphy results. Coronary imaging was performed in 20 of these 29 athletes. Four athletes showed significant coronary artery disease (positive predictive value = 20%). The positive predictive value increased to 33% when athletes were selected who should have undergone exercise testing according to the guideline recommendations. During a mean follow-up interval of 4.7 ± 2.2 years, eight cardiac events occurred. Athletes with an abnormal myocardial perfusion scintigraphy result had a fourfold increased risk at a future cardiac event (2.9%/year versus 0.75%/year, p = 0.031). Conclusions The positive predictive value of myocardial perfusion scintigraphy for the detection of significant coronary artery disease in asymptomatic athletes with a positive exercise testing result is low, even in a selection of athletes with a relatively high cardiovascular risk. Although an abnormal myocardial perfusion scintigraphy result was associated with a fourfold higher annual event rate, the absolute annual event rate in this group was still low. Efforts should be made to develop better diagnostic strategies to evaluate asymptomatic athletes with abnormal exercise testing results during pre-participation screening.

The Utility of a Novel Electrocardiogram Patch Using Dry Electrodes Technology for Arrhythmia Detection During Exercise and Prolonged Monitoring: Proof-of-Concept Study

BACKGROUND

Accurate detection of myocardial ischemia and arrhythmias during free-living exercise could play a pivotal role in screening and monitoring for the prevention of exercise-related cardiovascular events in high-risk populations. Although remote electrocardiogram (ECG) solutions are emerging rapidly, existing technology is neither designed nor validated for continuous use during vigorous exercise.

OBJECTIVE

In this proof-of-concept study, we evaluated the usability, signal quality, and accuracy for arrhythmia detection of a single-lead ECG patch platform featuring self-adhesive dry electrode technology in individuals with chronic coronary syndrome. This sensor was evaluated during exercise and for prolonged, continuous monitoring.

METHODS

We recruited a total of 6 consecutive patients with chronic coronary syndrome scheduled for an exercise stress test (EST) as part of routine cardiac follow-up. Traditional 12-lead ECG recording was combined with monitoring with the ECG patch. Following the EST, the participants continuously wore the sensor for 5 days. Intraclass correlation coefficients (ICC) and Wilcoxon signed rank tests were used to assess the utility of detecting arrhythmias with the patch by comparing the evaluations of 2 blinded assessors. Signal quality during EST and prolonged monitoring was evaluated by using a signal quality indicator. Additionally, connection time was calculated for prolonged ECG monitoring. The comfort and usability of the patch were evaluated by a web-based self-assessment questionnaire.

RESULTS

A total of 6 male patients with chronic coronary syndrome (mean age 69.8, SD 6.2 years) completed the study protocol. The patch was worn for a mean of 118.3 (SD 5.6) hours. The level of agreement between the patch and 12-lead ECG was excellent for the detection of premature atrial contractions and premature ventricular contractions during the whole test (ICC=0.998, ICC=1.000). No significant differences in the total number of premature atrial contractions and premature ventricular contractions were detected neither during the entire exercise test (P=.79 and P=.18, respectively) nor during the exercise and recovery stages separately (P=.41, P=.66, P=.18, and P=.66). A total of 1 episode of atrial fibrillation was detected by both methods. Total connection time during recording was between 88% and 100% for all participants. There were no reports of skin irritation, erythema, or pain while wearing the patch.

CONCLUSIONS

This proof-of-concept study showed that this innovative ECG patch based on self-adhesive dry electrode technology can potentially be used for arrhythmia detection during vigorous exercise. The results suggest that the wearable patch is also usable for prolonged continuous ECG monitoring in free-living conditions and can therefore be of potential use in cardiac rehabilitation and tele-monitoring for the prevention of exercise-related cardiovascular events. Future efforts will focus on optimizing signal quality over time and conducting a larger-scale validation study focusing on both arrhythmia and ischemia detection.