Tuesday, March 17, 2009

To "D" or not to "D"?

"Dysplasia": the cardiac wall of an ARVD victim...(if this disturbs you scroll down to the happy wombat).

Arrhythmogenic right ventricular dysplasia / cardiomyopathy (ARVD/C) has been discussed in passing on this blog before . The Wikipedia page is a decent, if a bit technical description of the disease, the Cleveland Clinic has a more accessible layman’s explanation, and Johns Hopkins ARVD Center has more detailed information including the complete clinical diagnosis guidelines. There is also an excellent information clearinghouse and support group at http://www.arvd-arvc-info.com/.

In brief ARVD/C is a form of cardiac disease in which the heart muscle of the right ventricle is replaced over time by fat and/or fibrous tissue. The reason why ARVD/C keeps popping its head up here is that I am, symptomatically, a likely case of ARVD/C. To an ARVD/C specialist my ECG reads suspiciously, and my experiences leading up to my year-long heart saga are textbook ARVD/C signs and portents.

The “D/C” tacked onto the “ARV” seems, in many ways, to be indicative of the nuance required in diagnosing this disease, though the actual reason for the "Dysplasia / Cardiomyopathy" dual moniker is one of semantics. From what I have been able to discern different people in different places use the term interchangably, with no differential in the diagnosis. Dysplasia refers to an abnormality in the way cells replace each other as a body ages. As a dog person I always think of dysplasia in the context of the hip dysplasia common to large breeds. Cardiomyopathy is a general term for any disease of the heart muscle. Unlike dysplasia, cardiomyopathy does not imply a progressive deterioration.

So the question that has lately loomed over my head, and might or might not be answered by the results of my forthcoming genetic testing is this: is my condition progressive (i.e. heavy on the “D”) and is my heart turning into a fatty fibrous lump, accelerated by the fact that I continue to exercise? Or is my condition stable over time, and I merely have to learn to live with my ICD and the off-chance that some of the already-existing ablated scar-tissue might come back “on-line” as a dangerous arrhythmia.

My electrophysiologist Dr. Marchlinski subscribes to the latter theory. He has been, and continues to be, hesitant to give me an ARVD/C diagnosis. Initially, after my first visit, ARVD/C was a likely diagnosis, and I was advised according to the protocol for this disease, which includes a total moratorium on any exercise more strenuous than walking. But as tests came in, including repeat echocardiograms an MRI, angiogram, and the more invasive electrophysiology test, Dr. Marchinski grew more positive about my likely outcome. After my first ablation he declared that, once my arrhythmias were under control and my ICD installed, there would be nothing I couldn’t do (baring contact sports that might rattle the ICD).

This flies in the face of the more conservative approach to a “possible” case of ARVD/C. Regardless of my testing “clean” of any fatty fibrous tissue replacement beyond the pre-existing scar, it seems that my continuously funky EKG and past history of fainting and V-Tach is enough to imply a potential for long term progression that should be heeded. The ARVD/C specialists, in other words, say I’m damaging myself by continuing to exercise.

So my task as it stands is to triangulate all this information and decide how much, if any, exercise is going to be appropriate for me. Because the current gamut of opinion coming from extremely competent practitioners runs from “don’t worry, do as much as you want” to “you are doing permanent damage to yourself if you don’t stop”, this is pretty heady stuff. It also makes it clear just how inexact a science / art medicine is.