Sidebar: Emma Carney's EI-ARVC

Emma Carney is a former world champion triathlete. You can read about her palmares here. Most online explanations of her career-ending heart condition don't go into very specific detail about her "clinical presentation". (i.e the Wikipedia entry that says her ICD is implanted in her right ventricle)
Anyway, what is striking about Emma's case is that it spawned the first serious, peer-reviewed, medical journal article presenting the idea of an Exercise Induced ARVC that is apart from the conventional form of ARVC. This article was published in 2009 in the journal Heart, Lung and Circulation. Here is  the introduction:

Recurrent sustained exercise induced ventricular tachycardia (VT) in elite ultra-endurance athletes is a rare but serious problem. Recent studies indicate that most serious ventricular arrhythmias (VA) in elite endurance athletes arise from the right ventricle (RV).   In some the diagnosis may be arrhythmogenic right ventricular dysplasia/cardiomyopathy (ARVD/C). In others it is postulated that repeated extreme exercise may damage the RV thus providing a substrate for arrhythmias.  In such cases the term EIRVD/C is applicable.   Distinction between these two entities (ARVD/C and EIRVD/C) is important. ARVD/C is an inherited disorder characterised by progressive fibrofatty replacement of RV myocardium eventually leading to ventricular arrhythmias and right heart failure.   The underlying pathophysiology is a genetic abnormality of cell adhesion proteins such as plakoglobulin, desmoplakin, plakophillin-2, and desmoglein-2.    In patients with ARVD/C exercise may precipitate ventricular arrhythmias and aggravate or accelerate the condition but it is not the fundamental cause of the disorder. On the other hand EIRVD/Cis thought to be the cumulative result of repeated bouts of extreme endurance exercise each of which has caused a small amount of damage to the RV.   We report a case of exercise-precipitated recurrent sustained monomorphic ventricular tachycardia (VT) occurring in a 32-year-old multiple world champion female triathlete without a family history to suggest ARVD/C and in whom investigations support a diagnosis of EIRVD/C rather than ARVD/C.

The case report portion of the article goes on to explain her ARVD/C diagnostic criteria  - which are exactly the same as mine...apart from the bit about world status in triathlon...

An ECG showed sustained monomorphic VT with LBBB morphology. DC cardioversion was required. She subsequently suffered further similar episodes each related to exercise. A typical baseline ECG showed sinus bradycardia with anterior T wave changes. Echocardiography showed dilated ventricles with normal left ventricular systolic function but moderately reduced RV systolic function. An MRI scan  confirmed the above findings and showed no features to suggest ARVD/C. Coronary angiography was normal. An RV biopsy showed fibre hypertrophy with evidence of patchy fibrosis but no evidence of fatty infiltration... The absence of a family history and lack of typical changes on the MRI scan and cardiac biopsy make a diagnosis of ARVD/C unlikely in this case. Furthermore it is improbable that someone with ARVD/C could achieve world status in triathlon over such a long period of time with this diagnosis. We believe it more likely that the athlete suffers from the newly described condition EIRVD/C." 

Next episode: my heart - 5 years and 30,000 miles after epicardial ablations and ICD...