New Study on Pregnancy w/Mechanical Valves

[Guest]

Asian Cardiovasc Thorac Ann. 2005 Mar;13(1):30-3.
Anticoagulation in patients with mechanical valves during pregnancy.

Geelani MA, Singh S, Verma A, Nagesh A, Betigeri V, Nigam M.

Department of Cardiothoracic and Vascular Surgery, GB Pant Hospital, New Delhi 110002, India. [email protected].

Mechanical valve thrombosis is a life-threatening event, while pregnancy is associated with a hypercoagulable state. Thus, in pregnant women with mechanical valves, adequate anticoagulation becomes even more critical. This prospective study was conducted to establish a uniform anticoagulation regimen for these women. A total of 250 pregnancies in 245 women with mechanical heart valves were evaluated. The patients were divided into 2 groups: group 1 (n = 150) took oral warfarin throughout pregnancy and group 2 (n = 100) received subcutaneous heparin in the 1(st) trimester and oral warfarin for the other trimesters. Both groups received heparin at the time of delivery. There were no coumarin-induced fetal malformations. Minor thromboembolic episodes took place in 5 women in group 1 and 3 in group 2. Valve thrombosis occurred in 1 woman in group 2 and led to 1 maternal death in this series. The incidence of spontaneous abortion was similar between the groups. We conclude that warfarin is safe and convenient to use during pregnancy. The teratogenic effects of warfarin during the 1(st) trimester are overstated, and switching to heparin is not mandatory.

Al's Comment - It is too bad that they did not state the warfarin doses. A study in Italy several years ago found that there was little chance of birth abnormalities when the warfarin dose was 4 mg or lower. I have e-mailed the authors to see if they have this.

 

[catwoman]

Al's Comment - It is too bad that they did not state the warfarin doses. A study in Italy several years ago found that there was little chance of birth abnormalities when the warfarin dose was 4 mg or lower. I have e-mailed the authors to see if they have this.

Al:

Based on what we all know, it would be conceivable (forgive the play on words) for an aspiring mom-to-be who takes more than 4mg of warfarin to lower it by reducing vitamin K intake. But how little green stuff, oils, activity, etc. could a pregnant woman get by without compromising nutrition and overall conditioning?

 

[geebee]

I must say this seems to be promising. I hope it turns out to be true.

Did they say what the INRs were?

 

[Emma]

Thanks for posting that Al.

It's something I do think about every so often (and have worried about) when I consider Chloes future and having to explain her condition to her in more detail.

I'd be interested, as you say, to know what their warfarin dosages were, if you find out and I hope this has some bearing over here in the future on how women who want children are dealt with on warfarin.

Emma
xxx

 

[Guest]

There will be new drugs by the time Chloe is ready.

 

[tobagotwo]

Another abstract, this one from The American Journal of Obstetrics and Gynecology: http://www.ajog.org/scripts/om.dll/...ry=[abstract](coumadin,)[abstract](warfarin,)

September 2004 ? Volume 191 ? Number 3

Transactions of the Twenty-Fourth Annual Meeting of the Society for Maternal-Fetal Medicine
Pregnancy outcome in women with prosthetic heart valves

Anwar H. Nassar, MD, Elie M. Hobeika, MD, Hasan M. Abd Essamad, MD, Ali Taher, MD, Ali M. Khalil, MD, Ihab M. Usta, MD

Abstract

Objective This study was undertaken to evaluate the risks and pregnancy outcome in women with prosthetic heart valves on different anticoagulent regimens.

Study design A retrospective chart review of 82 pregnancies in 33 women with mechanical valve prostheses at a tertiary referral center from 1987 to 2002. The main outcome measures were major maternal complications and perinatal outcome.

Results The valve replaced was mitral (60.6%), aortic (18.2%), and both (21.2%). Fifty-four pregnancies (65.9%) resulted in live births, 9 (11.0%) had stillbirths (all on warfarin), and 12 (14.6%) had spontaneous and 7 (8.5%) therapeutic abortions (all on warfarin). The rate of spontaneous abortion was highest in women on warfarin throughout pregnancy (P < .01). The live birth rate was higher in women on heparin compared with those on warfarin (P < .01), and in those on heparin/warfarin compared with warfarin alone (P < .01). There were no maternal deaths; however, 3 patients had mitral valve thrombosis (2 on heparin and 1 on warfarin) necessitating surgery in 1 patient and medical thrombolysis in 2 patients. Hemorrhagic complications occurred in 5 patients, 4 of whom required transfusion.

Conclusion No single anticoagulant regimen confers complete protection from thromboembolic phenomena in pregnancy. Despite a high maternal morbidity rate, the perinatal outcome is acceptable when pregnancy progresses beyond the first trimester.

Again, there is no info on the dosage regimen, and the full article is a pay-as-you-go thing.

Best wishes,

 

[Guest]

I'll see if my student can get the full article for free.

 

[Guest]

It turns out that this was only an abstract, not an artice. At these big meetings they have poster presentations where you try out ideas for research or publication. A journal will publish all of these abstracts. They have not been peer reviewed as regular journal articles are. They can vary from poor quality to excellent research. Nothing except what is in the abstract is presented.