Pregnancy and its complications after cardiac valve replacement

Risks and pregnancy outcome in women with prosthetic mechanical heart valve replacement

BACKGROUND

Pregnancy after mechanical heart valve replacement is highly risky for both mother and child because of the aggravation of maternal heart function and adverse effects of anticoagulation therapy. In Japan, however, the risks and pregnancy outcomes in women with prosthetic mechanical heart valve replacement remain to be elucidated.

METHODS AND RESULTS

In the present study 16 pregnancies in 12 women with prosthetic mechanical heart valve replacement were identified between 1983 and 2005. At 6-13 weeks of gestational age, warfarin, an anticoagulant agent, was changed to heparin and administration was continuously adjusted according to the activated partial thromboplastin time level up to the time of delivery. Major maternal complications and pregnancy outcomes were retrospectively investigated. The valve replaced was mitral (n=7), tricuspid (n=7), and aortic (n=2). Eight (50%) of 16 had cesarean live births. One case was delivered at full term, and 7 cases were delivered preterm (26-36 weeks) because of maternal indications. Two babies died in the neonatal period. Therapeutic abortion was performed in 3 cases, 4 cases ended in early miscarriage, and 1 case ended in intrauterine fetal death (30 weeks). Three mothers developed valve (mitral, tricuspid, aortic) thrombosis. There was 1 maternal death from heart failure.

CONCLUSIONS

Pregnancy after mechanical heart valve replacement requires strict control of coagulation. Special attention should be paid to the occurrence of complications during anticoagulation therapy.

Anticoagulation therapy during pregnancy of patients with artificial heart valves: fetomaternal outcome

OBJECTIVES

The major problem is the need for anticoagulant therapy in patient with mechanical heart valves.

STUDY DESIGN

The aim of the study was to analyze the course and outcome of pregnancies of patients with artificial mechanical heart valves with anticoagulant therapy. Study included 43 pregnancies leaded and terminated at the Institute of Gynecology and Obstetrics Clinical Center of Serbia in 20 years. We divided the patients in two groups depending on the type of anticoagulation therapy. Group I included 21 patients who were under Ethylbiscumacetate (Pelenthan) during the first 36 weeks of gestation, and intravenous Heparin in the last 4 weeks and after the delivery. Group II included 22 patients who received oral anticoagulant therapy all the time.

RESULTS

Worsening of the heart functional status happened in 6 patients (13.9%). The incidence of heart failure during the pregnancy was 13.9% and after the delivery 9.3%. The incidence of hemorrhagic complications was 11.6% during pregnancy and 14% after the delivery. Four patients had thromboembolic events before the pregnancy. The incidence of postpartal thromboembolic complications was 6.9% in group I. Two patients died due to the heart failure 3-7 days after the vaginal delivery. Maternal mortality was 4.6%. One neonatus died of hydrocephalus (2.5%) in group II. In our study there were no fetuses with congenital heart disease.

CONCLUSIONS

Pregnancies of patients with mechanical heart valves should be planned. We suggest ethylbiscumacetate in combination with Heparin as anticoagulation therapy during the pregnancy.

Epidural blood patch in a patient taking enoxaparin

A 36-year-old, 204-kg parturient with a past medical history of Factor V Leiden requiring enoxaparin therapy developed a postdural puncture headache. With careful coordination of her enoxaparin dosing, an epidural blood patch was successfully performed. Performance of a blood patch in patients taking enoxaparin involves the withholding of the medication for a specific period.

Feto-maternal morbidity and mortality after cardiac valve replacement

BACKGROUND

The aim of this study is to evaluate the fetomaternal morbidity and mortality of the pregnancies of women who conceived after cardiac valve replacement.

METHODS

A consecutive series of one hundred and thirty-six pregnancies of one hundred and one patients who conceived after cardiac valve replacement were retrospectively analyzed. Regarding the anticoagulation therapy, 101 patients were classified into three groups: A: patients on oral anticoagulants (n=68), B: patients on heparin (n=16) and C: patients who received no anticoagulation (n=17).

RESULTS

Three groups (patients on oral anticoagulants (A), on heparin (B), patients who received no anticoagulation (C)) were compared in terms of spontaneous abortion (19%, 11%, 5.6%), preterm delivery (14%, 22.3%, 16.6%), maternal mortality (3%, 11.1%, 0%), thromboembolic events (4%, 11.1%, 0%), cardiac failure (6%, 11.1%, 11.1%), atrial fibrillation (9%, 11.1%, 5.6%), antenatal bleeding (9%, 11.1%, 5.6%), delivery route and fetal malformation (5%, 0%, 0%) and no statistically significant differences were detected. In group B, hematoma formation rate (22.2%) (p=0.011) and transfusion rate (27.8%) (p=0.005) were significantly higher. Five cases of congenital anomalies were detected, all belonging to group A, but this tendency was not found to be statistically significant.

CONCLUSIONS

Management of pregnancies with prosthetic heart valves require closely monitored anticoagulation, and an obstetrician should be familiar with the potential fetal and maternal adverse effects of any anticoagulant therapy during the course of pregnancy.

Effect of pregnancy on the duration of bovine pericardial bioprostheses

BACKGROUND

This study sought to evaluate the effect of pregnancy on the rate of deterioration of bovine pericardial bioprostheses. To avoid the fetal and maternal risks associated with anticoagulant therapy during pregnancy, the use of bioprostheses has been advocated for young women with cardiac valve disease who may later wish to bear children. Several reports have suggested the probability of pregnancy-related accelerated deterioration of these valves.

METHODS AND RESULTS

The incidence of prosthetic dysfunction and the freedom from deterioration were investigated in 48 women who had 58 pregnancies and in a control group of 167 patients in the same age range. There were 39 cases of prosthetic dysfunction (deaths plus reoperations resulting from valve failure): 12 in the pregnant group for a linearized rate of 3.5% +/- 0.99% (SE) per patient-year and 27 in the control group or 3.4% +/- 0.65% per patient-year (P = not significant). The actuarial freedom from dysfunction was 90.4% (95% confidence interval 77.9 to 96.2) at 5 years and 77.0% (59.7 to 88.3) at 8 years for the pregnancy group and 86.3% (77.3 to 92.0) and 73.4% (56.6 to 84.8), respectively, for the control group ( P = not significant). In the Cox proportional hazard regression analysis, pregnancy did not influence dysfunction. A direct correlation was found between freedom from dysfunction and the patient's age at surgery.

CONCLUSIONS

Pregnancy does not accelerate the rate of deterioration of bovine pericardial bioprostheses. It is more likely that biological valves deteriorate more rapidly in these patients because of their young age.

Pregnancy and bioprostheses: influence on structural valve deterioration

The long-term performance of bioprostheses was evaluated in women 35 years of age or less to determine the influence of pregnancy on structural valve deterioration. Between 1972 and 1992, 237 female patients received 255 biological prostheses. Of the total operations, 53 were performed in patients who experienced pregnancy (P) and 202 in patients who were never pregnant (nonpregnant [NP]). The mean age of the P group was 23.0 +/- 5.8 years (standard deviation) (12 to 34 years) and of the NP group it was 27.1 +/- 6.3 years (8 to 35 years) (p < 0.05). The mean follow-up for the NP group was 6.8 years and for the P group it was 7.9 years. The late mortality was 2.26%/patient-year overall, 2.71%/patient-year for the NP group and 0.89%/patient-year for the P group (p = not significant [NS]). The P group of 52 patients had 94 pregnancies: 70 deliveries (74.5%) and 24 abortions (25.5%) (therapeutic, 14 [15%]). There were a total of 143 valve-related complications (P, 35; NP, 108); the majority for structural valve deterioration (SVD) 43% (109 patients), P 51% (27 patients) and NP 41% (82 patients) (p = NS). The valve-related reoperation rate paralleled the SVD rate at 42% (107 patients), P 51% (27 patients) and NP 40% (80 patients) (p = NS). The overall reoperative mortality rate was 6.0%. The interval from initial implant to reoperation was 99.6 +/- 3.6 months (p = NS groups P and NP).(ABSTRACT TRUNCATED AT 250 WORDS)

Valvular heart surgery during pregnancy

The pathophysiology of mitral and valvular heart disease is presented with an emphasis on the relationship of these conditions to pregnancy. Management options are discussed. Special attention is directed to patients who have prosthetic valves in place and who become pregnant. The care of this group of patients may be difficult, and treatment strategies are presented.

Home heparin therapy used in a pregnant patient with a mechanical heart valve prosthesis

The optimal anticoagulation therapy for pregnant patients with a mechanical valve prosthesis is uncertain, but teratogenic effects and the high incidence of fetal loss associated with dicumarol derivatives limit the use of these agents as anticoagulants in this setting. A patient with a mechanical valve prosthesis, in the first trimester of pregnancy, stopped taking her warfarin because of personal fears about teratogenicity. Prosthetic valve thrombosis developed, and she required redo mitral valve replacement. Another mechanical prosthesis was inserted without maternal or fetal injury. The patient was maintained on continuous home, intravenous, high-dose heparin therapy for the remainder of her pregnancy. This therapy resulted in a successful pregnancy and delivery without valve thrombosis, hemorrhagic events, or maternal or fetal compromise.

Pregnancy outcome in women with cardiac valve prosthesis

Twenty-one pregnancies in 16 women who conceived after cardiac valve replacement were reviewed. Oral anticoagulants were discontinued before conception or as soon as possible for subcutaneous heparin treatment (8000-14,000 IU every 8-12 h) and resumed in the second trimester until the last period of pregnancy when oral anticoagulants were replaced again by heparin. No therapeutic abortion was performed. The spontaneous abortion rate was found to be 14.3% (3/21). Preterm delivery (< or = 37 weeks) and low birth weight babies (< 2500 g) were 29.4% (5/17) and 35.3% (6/17), respectively, significantly more frequent than those of the control group (P < 0.02 and P < 0.0005). No significant statistical difference was found when the rate of spontaneous abortion [14.3% (3/21)] and the rate of fetal growth retardation [11.8% (2/17)] were compared with the control group. The majority of thromboembolic events (6/7) occurred during heparin regimen in three mothers; one of them subsequently died. No coumarin embryopathy was observed and the physical and mental development in the 16 surviving children was good. This study confirms: (1) the increased rate of preterm delivery and infants weighing < 2500 g; (2) the increased risk of maternal thrombosis related to heparin use; and (3) the good follow-up in the surviving children.

Outcome of pregnancy in women with valve prostheses

OBJECTIVE

To study the outcome of pregnancy in women with artificial heart valves treated in major European centres, and to compare the safety and efficacy of different anticoagulant regimens and of mechanical and bioprosthetic valves.

DESIGN

Retrospective study.

METHOD

The information was obtained by questionnaire sent to all major cardiac centres in Europe sending one cardiologist from each centre a covering letter suggesting that the questionnaire be handed on where appropriate to the most relevant colleague.

RESULTS

214 pregnancies were reported in 182 women; 151 pregnancies in 133 women with mechanical valves, and 63 pregnancies in 45 women with bioprostheses. Most women were in New York Heart Association class I or II and in sinus rhythm. 150 women with mechanical valves and 11 (17%) with bioprostheses received anticoagulants during pregnancy. One patient with an aortic valve prosthesis refused to take anticoagulants. Including the spontaneous abortions reported as well as the therapeutic abortions 83% of the pregnancies in women with bioprostheses and 73% in those with mechanical valves resulted in a healthy baby, full term or premature, who did well (NS). The incidence of stillbirths (3% and 6%) and of reported spontaneous abortions are excluded (because they are unlikely to have been fully reported), the success rate was 91% for women with bioprosthetic valves and 84% for women with mechanical valves (NS). 114 (53%) of the women had taken warfarin for some part of the pregnancy (46 (40%) of these during the first trimester) but there were no embryopathies. There were 13 valve thromboses (four fatal), eight embolic events (two fatal), and seven bleeds in women with mechanical valves. Most of these complications occurred with heparin but fatal aortic valve thrombosis occurred in the one woman who refused anticoagulant treatment out of the 151 women with mechanical valves. There were no maternal deaths in the bioprosthesis group but in 17/49 (35%) of these valves functional deterioration led to urgent replacement during pregnancy (two) or soon after.

CONCLUSIONS

The outcome of pregnancy was similar for women with mechanical valves or bioprostheses. Warfarin treatment was safe and effective and was not associated with embryopathy. Heparin treatment was associated with more thromboembolic complications and more bleeding complications. Bioprostheses deteriorate rapidly during pregnancy.