Alert & Oriented

This study reports on a cohort of competitive cross country skiers 28-30 years after an initial evaluation.  There is no control group.  The initial evaluation was in 1976 and included 122 participants classified into 3 age groups at baseline: group I 26-33; group II 43-50; group III  58-64.

At follow-up in 2004-2006, 37 had died (most in the older age group) and 11 were lost to follow-up.  Among the 78 remaining ones, 17% had AF and 13% lone AF.  Broken down by age group, the AF prevalence was 18% in group I, 14% in group II and 25% in group III.

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As expected, the subjects with AF had larger atrial sizes when measured at follow-up.  LV mass was not measured (the less sensitive wall thickness was similar among AF and non-AF subjects).

The baseline data were limited to physical examination, PFT’s, ECG at rest and with exercise, as well as VO2 max measurement.

A slow heart rate and prolonged PQ interval, both indicators of vagal tone, were strong discriminant of the future risk of AF in the younger age group (HR 44 ± 5 for LAF and 53 ± 9 for sinus subjects; PQ 0.17 ± 0.05 for LAF and 0.17 ± 0.02 for sinus subjects).  A similar pattern was found for the overall cohort, although the effect was not as strong.

Intensity and duration of training, height (at follow-up), thyroid tests and HgA1c (at follow-up) were not associated with AF status.

Take-home:  This supports the hypothesis that AF in endurance athletes may be significantly impacted by autonomic tone. A speaker at this year’s ACC meeting emphasized the same point.

Note: paternity-related editorial delay…

This paper is yet another report from the Physician’s Health Study, a very large and very old clinical trial/prospective cohort study that followed some 22,000 physicians by questionnaire administered at various time points.  One initial aim of the study was to test any mortality benefit of some primary prevention measures (daily aspirin, beta-carotene), but enough data was collected that numerous other associations (or lack of) have been reported over the years.  This particular report looked at the association between responses to exercise questionnaires administered at the 3-year and 9-year time points in the study, and subsequent development of atrial fibrillation (self-reported). Continue Reading »

A young woman who collapsed and died during the 2012 London Marathon was found to have detectable levels of DMAA in her bloodstream. She had apparently obtained this “nutritional supplement” online.  The story is reported in theheart.org and elsewhere in the press.

The coroner Philip Barlow (not to be confused with Philip Marlowe!)  is decidedly non-committal:

She had taken a supplement containing DMAA, which on a balance of probability, in combination [with] extreme exertion, caused cardiac failure, which resulted in her death.

Apparently, there was no obvious cardiac abnormality at autopsy. Continue Reading »

I had overlooked this earlier article published in 2006.  Heidbuchel and colleagues have written extensively on right ventricular problems in athletes, and I may review that literature in due time.

For this particular study they looked at outcomes after consecutive cases of atrial flutter ablation performed between 1999 and 2003.  Their EP center happened to routinely administer an exercise questionnaire to all ablation patients as part of another study on cardiac risk factors.  The questionnaire was apparently reasonably detailed. Continue Reading »