In March of 2008 I began treatment for a potentially fatal heart arrhythmia whose cause was unknown. I was fit and healthy, having spent a good part of my adult life as an elite cyclist, much of it racing in Europe.
After 5 years of fence-sitting on the part of my doctors, I have been given a diagnosis of ARVD/C (Arrhythmogenic Right Ventricular Dysplasia / Cardiomyopathy). I lack the known genetic markers for the disease as well as some of the structural changes that accompany ARVD/C, and my condition has shown no indication of being progressive (yet).
There is a growing population of current and former endurance athletes who end up with acquired arrhythmias, and a diagnosis of ARVD/C. But by placing these athletes in the ARVD/C patient population, we are potentially ignoring the very real likelihood of an acquired condition, similar, but different, from ARVD/C.
This blog is written as a resource for athletes with acquired arrhythmias, as well as anyone about to undergo endo or epi-cardial ablation, or the implantation of a ICD. It is also written to help generate some critical mass of interest in support of further research into acquired arrhythmias in endurance athletes and others. Feel free to contact me through the comments page if you have any questions or wish to make a written contribution to this blog.

Sunday, August 18, 2013

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...

1 comment:

Pamela Dexter said...

Miss Carney,

I hope you are well. My step-sons and husband have ARVC/D although all my husbands test are not in, everything pointing that way. I do not see much on the internet and don't if you still check this site but it is all a bit scary.
Our eldest was diagnosed at 17 and at the time was a champion water polo player with colleges at his beckon. Two months ago our 29 year old very athletic son was in cardiac care in NZ for 2 weeks and same diagnosis. Now this
week we know (although not to what degree) my husband (67) and a sea urchin diver, waterman extrodinaire with the
same. I am more afraid of the drugs for them. The ICD is a protective measure but I will be seeking alternative ways
to deal with the symptoms. I may not be successful but am looking to see if anyone has forged that road?? Hoping to possibly reduce the amount he may have to take. Blocking your adrenaline is so drastic from what I gather. The medical community right now seems to have a single approach. Help...concern Mom and wife.