Question about virus & ppcm

[kariefristoe]

Hi Dr. Fett~

I've been thinking about this lately and was wondering if you could shed some light onto this subject because it has me wondering. You've posted in the past that there is a possibility that certain viruses could trigger ppcm (I know this is just a theory as of now and something they are researching more into). However, if a girl has recovered after her pregnancy with an EF higher than 50% then why do some girls have a reoccurance if others do not with a post ppcm pregnancy....does the virus still play a part in the subsequent pregnancies? Just curious

[JAMESFETT]

Good question, in fact the very one that researchers are trying to answer, and need to answer.

If one considers some IDCM, and viral DCM comparable to PPCM, there is evidence that unless there is viral clearing from the heart, recovery may not occur, or relapse may occur. Hence, there is a possibility in PPCM, that relapse occurs in subsequent pregnancy, it could be because the viral cause, if there is a viral cause, is still present in the heart, even if in a latent state.

If the cause is something other than virus, then a relapse in some but not in others could be explained by the ongoing presence of that unidentified factor in some, but not in others.

How do we get to the answer? For one, we must do more investigation of presence or absence of virus in heart muscle when endomyocardial biopsies are done for those PPCM patients who are not adequately improving in the first few months.

So far, two investigators have found virus in the heart muscle of PPCM patients, and I think their findings are very important. One investigator did not find virus in heart muscle of PPCM patients, but he biopsied different sites and at a different time. So we need more studies.

In Haiti, we are presently looking at the possibility of Zinc deficiency accounting for the ten-fold increased incidence of PPCM in Haiti compared to PPCM in the USA. If Zn deficiency does play a role, it would probably be through making certain viruses more able to have negative effects on the heart (more pathogenic). That has occurred in animal models. I don't expect that Zn deficiency would play any role in PPCM in the USA, but I do suspect that the same cardiotropic viruses do.

JD

[reezlemom]

I've had the same question. From what I've read I've always thought that my prior CMV had something to do with this, or possibly a horrible virus I had early in my pregnancy. Either way, my hesitation about pursuing a subsequent pregnancy hinges heavily on the feeling I have that the responsible party may still be hanging out in my body, dormant.

But this does raise another question. If a women developed PPCM due to a latent virus, and the pregnancy re-activated it thereby causing the cardiomyopathy, what kind of risks would she be looking at with a subsequent pregnancy? I would think it would be a real "roll of the dice" so to speak in such a situation, even with fully recovered heart function. Or does a normal contractile reserve prove clearance of the virus from the heart?

[Erin]

I don't expect that Zn deficiency would play any role in PPCM in the USA, but I do suspect that the same cardiotropic viruses do.

JD

Dr. Fett, why might Zn deficiency not play so much a role in PPCM in the US, is that because we generally get enough Zn through the average US diet?

This is interesting to me because many years ago I had some biochemical work done and one thing my doctor told me was that I seem to have trouble metabolizing zinc and that I was slightly deficient in zinc. He prescribed me 75 mg. of zinc/daily (among other things) in fact. Is there any possible connection there, or still not likely?

Thanks.

[JAMESFETT]

Because there is no real dietary deficiency of Zn in the USA. However, in Haiti, and in many other developing countries, up to one-third of the population may have diets deficient in Zinc. A word of caution: it is possible to over-supplement zinc. The average daily need is in the 10 to 20 mg range.

JD

[JAMESFETT]

Fully recovered PPCM patients with normal contractile reserve would be very unlikely to have latent virus present in myocardium (assuming that viral infection plays a major role in the cause of PPCM). I particularly base this opinion upon the work of Uri Kuhl and colleagues in Germany, working with known viral cardiomyopathy, and reported in Circulation.

JD

[tabs]

Could the difference in relapse rates of PPCM be also related to heart function prior to the initial PPCM pregnancy? I wonder if there is the possibility that some of us may have IDCM, but were lumped in with PPCM because we finally had symptoms that brought us to be checked out while pregnant or in the post-partum period. If that is the case, then that could explain why some recover faster or why some don't fully recover.

Twilah

[JAMESFETT]

Yes, unless one knows the echocardiographic function just before pregnancy one does not know if there might have been a previously-existing cardiomyopathy. Most women and most women with newly-diagnosed PPCM begin pregnancy without having ever had an echocardiogram. Of course the low incidence rate of PPCM does not justify doing an echo on every woman at the onset of pregnancy--unless one lives in a high-incidence area for PPCM, in which case it may be justified to do an echo during the last trimester of pregnancy in everyone.

JD

[reezlemom]

Thank you Dr. Fett for clearing that up. Knowing that, maybe I won't shut down the baby making equipment just yet. I was one who had the benefit of prior echos too, so I know I had no existing cardiomyopathy until after my second pregnancy.