Dilated Cardiomyopathy and Atrial Fibrillation

[Scubapro146]

Dear Dr. Decompression:

I am a 29 year old male and was just recently diagnosed with Dilated Cardiomyopathy, Atrial Fibrillation and Congestive Heart Failure. I have been diving since 1993.
I have been relatively healthy since I was a kid other than having scarlet fever once a long time ago and I still suffer from seasonal allergies.

Could this heart ailment have been caused by diving? I have always stayed within the recreational limits and have never had a bends hit or DCS.

Is this something that pressure at depth over years of diving could have caused?
:11:

 

[Dr Deco]

Hello scubapro:

From what I read about this disorder, it does not appear that diving per se could cause it.

I am sure that the other medical facilitators on the BOARD will have some comments eventually.

Dr Deco :doctor:

The next class in Decompression Physiology for 2006 is September 16 – 17. :1book: http://wrigley.usc.edu/hyperbaric/advdeco.htm

 

[TSandM]

Quoted from an article in the Italian Heart Journal:

Dilated cardiomyopathy (DCM) is a heart muscle disease characterized by impaired contractility and dilation of the left ventricle or both ventricles. In a large proportion of patients, the cause of the disease is unknown and DCM is considered to be the final common phenotype of a heterogeneous group of disorders. Molecular studies carried out in specific DCMs have identified several metabolic and structural defects leading to a common phenotype of myocardial damage. Viral infection and autoimmune disorder can cause DCM. However, a familial trait is present up to 50% of cases, indicating a major role of genetic factors. The analysis of the phenotype, the pattern of genetic transmission, and molecular genetic findings have allowed the characterization of different forms of familial DCM, suggesting genetic heterogeneity. Furthermore, the risk of disease has been estimated as high as 20% in relatives of familial DCM patients, which is significantly higher than the normal population. Taking into account that DCM can be clinically not evident due to its low penetrance (in particular in the young population), a reproducible and reliable method for the diagnosis of familial forms is critical in the management of the disease. To address this issue, consensus guidelines for the diagnosis and screening of familial DCM have been developed. The screening method for familial DCM is based on physical exam, electrocardiogram, and echocardiogram of first-degree relatives of affected subjects. The family screening should be followed-up every 2 to 3 years, in particular in unaffected relatives (in the absence of a molecular diagnosis), to exclude a late onset of the disease.

I am not aware of anything that suggests the incidence of this ailment is higher in divers -- but the ailment itself is not common, and the number of divers is not that great, so it would take a lot of time to see anything but a gross change in the incidence rate. I also really can't come up with a plausible mechanism for how this illness would be caused by diving.

 

[Scubapro146]

I went to another Doctor yesterday for a second opinion. He ran an Ultrasound / Sonigram and another EKG. Apparently the meds I am on are working. My heart functionality rate is up to 30% from below 15% initially with 55-60% being the normal so I was pleased to hear that. I was told earlier by the Cardio Hyperbaric specialist DR in Philadelphia that conservative diving is ok as long as the heart functionality rate increases to 40-45%. I see my local cardio again in 2-3 weeks and hopefully will have even better news by then. There maybe a slight chance I could do a couple of shallow dives in Brockville come August but I'm not going to push it and it will depend on how much more progress my heart has made. Please share any thoughts you may have. Information is always appreciated! Tanks to all.

 

[Dr. Doug Ebersole]

I'm a cardiologist with an interest in diving medicine. There is no known link to dilated cardiomyopathy (DCM) from scuba diving. I assume you have no history of other family members with the disorder and given your young age it would be extremely unlikely to be due to reported causes such as long-standing diabetes, hypertension, alcohol abuse, etc. The most common causes of the disease in your age group would be either a viral cardiomyopathy or what we call "idiopathic" which means we don't know why it happened to you.

A significant number of people with DCM recover some or all of their heart muscle function within several months of the diagnosis but some do not. Close follow-up and medical therapy with you cardiologist is paramount. After a "period of time" to be defined by your doctors you should be able to return to diving as long as you have good exercise tolerance. It is usually recommended that you be able to complete 12 minutes on a standard Bruce protocol treadmill test before returning to diving. If you have any specific questions you would like to discuss but not on a public message board, feel free to PM me.

Good luck and I hope you're back in the water soon!

Doug