GENEVA — Cardiac screening before participating in sports isn’t just for the young, according to a study suggesting that first-time marathon runners who are middle aged also need examination for risky heart conditions.
Screening questionnaires and 12-lead electrocardiography along with history taking and blood work caught cardiac problems that disqualified 2% of novice participants in a 30-km (18.6-mile) cross country race, Philip Aagaard, a medical student at the Karolinska Institute in Stockholm, and colleagues found.
Questionnaires alone weren’t enough, Aagaard warned in his presentation of the data here at the European Society of Cardiology’s EuroPRevent meeting.
An abnormal history of chest pain, palpitations, or dyspnea identified through the questionnaires led to four of the 153 runners getting further work-up but all turned out to be irrelevant, yielding a fairly high false positive rate, he noted at the session.
Endurance races are increasingly popular at all ages, but middle age groups have been largely overlooked in pre-participation screening, which has focused more on children and elite athletes, Aagaard noted in an interview.
American guidelines recommend ECG for adults with at least one risk factor but are not mandatory for endurance race participation, he added.
His group conducted detailed cardiovascular screening, as recommended in new European guidelines for middle-age and older athletes, for all men age 45 and older running the Lidingöloppet race in Sweden for the first time.
Of these 153 novices screened, 12 required further diagnostic work-up. This work-up included exercise ECG for 11 of them, 48-hour Holter monitoring in four, and exercise echocardiography in three.
One patient needed 24-hour blood pressure monitoring, signal-averaged ECG, cardiac MRI, and trans-esophageal echocardiography for what turned out to be an atrial tumor and was sent to surgery instead of the race.
Four patients were found to have a long QT-interval, two of whom were disqualified from the race due to an interval over 500 ms, which could predispose them to exercise-related sudden cardiac death.
Michael Papadakis, MD, of St. George’s Hospital in London, cautioned in the question and answer period that the roughly 1 in 100 rate for long QT syndrome found in the study was far above the 1 in 2,000 to 1 in 4,000 rate suggested for the general population in the literature.
Aagaard agreed that the prevalence in the study could have been a chance finding.
High blood pressure (180/110 mm Hg), T-wave inversions considered a normal variant, paroxysmal atrial fibrillation, and mitral valve prolapse were all found as well but not considered grounds for disqualification.
Aagaard noted that NT-proBNP measurements had been hoped to be predictive of need for further work-up but were not positive in any of the screened individuals.
Nor did any of the runners — typically fit and active individuals — have evidence of coronary artery disease, although at least some cases would have been expected, he pointed out as a limitation of the study.
“Since this is the leading cause of sudden cardiac death in this age group in exercise, further studies will need to address this issue,” Aagaard told attendees.
Perhaps some kind of imaging would have been needed to catch those cases, he suggested, noting that the best way to screen such athletes remains unclear.
“This problem exactly highlights the problem with screening master athletes [those in middle age and older] in using exercise tolerance tests, which have a very high false negative and false positive rate,” said Papadakis, who serves on the sports cardiology panel for the ESC group that sponsored the conference.
He noted that British recommendations have removed exercise tolerance testing for these reasons.
Aagaard and Papadakis reported having no conflicts of interest to disclose.