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 the heart

Pregnancy places a huge demand on the heart. Such a burden cannot always be met by women with pre-existing heart disease. This article covers the important physiological changes of healthy pregnancy, and discusses how to assess and manage heart disease during pregnancy.

A strategy for reducing maternal mortality

A confidential system of enquiry into maternal mortality was introduced in Malaysia in 1991. The methods used and the findings obtained up to 1994 are reported below and an outline is given of the resulting recommendations and actions.

Hypertension in women with gestational diabetes

Hypertension in pregnancy and gestational diabetes have in common a lack of universally accepted classification and nomenclature that hinders comparison of data between research groups and contributes to the lack of consensus in the literature on these conditions. The inter-relationship of hypertension and gestational diabetes can be considered from three viewpoints according to whether hypertension is present before, during, or after the pregnancy. The first question is whether hypertension predating pregnancy predisposes to gestational diabetes. Epidemiological evidence and physiological argument based on the common etiologic factor of insulin resistance would suggest that gestational diabetes should be more common in the presence of preexisting hypertension. The limited clinical data available support this hypothesis. There are three issues concerning the coexistence of hypertension and gestational diabetes: whether gestational diabetes predisposes to pregnancy-induced hypertension, whether pregnancy-induced hypertension predisposes to gestational diabetes and what effect the combination has on morbidity and mortality. A number of studies have investigated whether pregnancy-induced hypertension is more common in women with gestational diabetes, but no consensus has been reached. There is little direct clinical evidence on the reverse issue, but data are presented to suggest that pregnancy-induced hypertension may only predispose to gestational diabetes when its etiology is gestational hypertension and not preeclampsia. The issue of how the coexistence of pregnancy-induced hypertension and gestational diabetes affects maternal or neonatal morbidity and mortality is largely unanswered. The last question is whether gestational diabetes has any prognostic significance with regard to the future development of hypertension in the mother. It is well known that gestational diabetes predisposes to subsequent NIDDM and that NIDDM is associated with a high incidence of essential hypertension. Once again insulin resistance may be a unifying factor. However, there is no direct clinical evidence that gestational diabetes predisposes to future hypertension.

Outcome of pulmonary vascular disease in pregnancy: a systematic overview from 1978 through 1996

OBJECTIVES

Published reports were reviewed to evaluate the characteristics of peripartal management and the late pregnancy outcome in women with pulmonary vascular disease (PVD).

BACKGROUND

Pulmonary hypertension poses one of the highest risks for maternal mortality, but actual data on the maternal and neonatal prognosis in this group are lacking.

METHODS

Reports published from 1978 through 1996 of Eisenmenger's syndrome (n = 73), primary pulmonary hypertension (PPH) (n = 27) and secondary vascular pulmonary hypertension (SVPH) (n = 25) complicating late pregnancy were included and analyzed using logistic regression analysis.

RESULTS

Maternal mortality was 36% in Eisenmenger's syndrome, 30% in PPH and 56% (p < 0.08 vs. other two groups) in SVPH. Except for three prepartal deaths due to Eisenmenger's syndrome, all fatalities occurred within 35 days after delivery. Neonatal survival ranging from 87% to 89% was similar in the three groups. Previous pregnancies, timing of the diagnosis and hospital admission, operative delivery and diastolic pulmonary artery pressure were significant univariate (p < 0.05) maternal risk factors. Late diagnosis (p = 0.002, odds ratio 5.4) and late hospital admission (p = 0.01, odds ratio 1.1 per week of pregnancy) were independent predictive risk factors of maternal mortality.

CONCLUSIONS

In the last two decades maternal mortality was comparable in patients with Eisenmenger's syndrome and PPH; however, it was relevantly higher in SVPH. Maternal prognosis depends on the early diagnosis of PVD, early hospital admission, individually tailored treatment during pregnancy and medical therapy and care focused on the postpartal period.

Pregnancy and pre-existing heart disease

Heart disease is encountered in nearly 1% of pregnancies, and the incidence is increasing. This is likely due to advances in cardiac management over the past 25 years, particularly advances in cardiac surgery and drugs, which have allowed more women with congenital and other abnormalities not only to survive to reach the age of child-bearing but also to carry a pregnancy to term successfully. Cardiac diseases of particular importance include stenotic valvular lesions, cyanotic disorders, and lesions accompanied by pulmonary hypertension. These abnormalities are associated with increased fetal and maternal morbidity and mortality, and therefore require very close monitoring during pregnancy. The physician also should be familiar with the more common cardiac disorders seen in pregnancy, be familiar with cardiovascular drugs and their potential effects on the pregnant patient and fetus, and be aware of cardiac disorders which are relative and absolute contraindications to pregnancy due to high rates of maternal mortality.

The outcome of peripartum cardiac failure in Zaria, Nigeria

We have studied 227 women who had peripartum cardiac failure (PPCF) in Zaria, Nigeria, since 1969-72. This follow-up and review of survivors in 1993-95 depended chiefly on a Zaria woman (A. Abdullahi) and on her careful reporting. Overall, 31 (13.7%) were completely lost to follow-up, 17 (7.5%) were thought to be alive, and there were data on 179 others (78.8%). Of the 75 known deaths, 55 were cardiovascular--20 due to PPCF, 31 due to cardiac failure unrelated to pregnancy (CF), and four were due to a cerebrovascular accident. PPCF recurred in 13% of 551 subsequent pregnancies. Thirty-two women had a recurrence of PPCF only, and 27 an episode of CF only. Blood pressures rose steadily over the years. An enlarged left ventricle on discharge after the index admission predicted a poor prognosis. In 1993-5, we compared 100 survivors with 100 non-PPCF controls: 96 PPCF women but only 50 control women took extra salt (p = 0.0001). Significantly more PPCF women than controls had a diastolic pressure of 110 mm Hg (p = 0.011). The syndrome is probably provoked in potentially hypertensive women by the traditional practices of eating kanwa, which is rich in Na+, taking additional excess salt and heating the body after delivery. Evidence is presented that PPCF women are potentially hypertensive, and cannot handle the excess ingested sodium which therefore leads to hypervolaemia and thus PPCF.

The incremental risk of female sex in heart transplantation: a multiinstitutional study of peripartum cardiomyopathy and pregnancy. Cardiac Transplant Research Database Group

BACKGROUND

Controversy remains regarding the reason females seem to be at increased risk for rejection after heart transplantation. Therefore this study was performed to define the effect of a pretransplantation diagnosis of peripartum cardiomyopathy and the effect of previous pregnancy on the outcome (incidence of rejection and death) of females after heart transplantation.

METHODS

In this multiinstitutional study of 3244 adult (greater than 13 years of age) heart transplant recipients, (a) the outcome of 40 females who underwent transplantation for peripartum cardiomyopathy was compared with that of 200 females of childbearing age (13 to 45 years) who underwent transplantation for other indications and (b) the posttransplantation outcome of 543 females with a history of pregnancy was compared with that of 101 nulliparous adult females and 2562 adult males.

RESULTS

The posttransplantation outcome of females with a history of peripartum cardiomyopathy was similar to that of females of childbearing age who underwent transplantation for other indications. However, parous females had a significantly shorter time to first rejection (p < 0.0001) and greater cumulative rejection than nulliparous females or males. By multivariable analysis, the risk factors for cumulative rejection at 1 year were a history of pregnancy (p < 0.0001), younger recipient age (p < 0.0001), induction therapy (p < 0.0001), and the number of human leukocyte antigen-DR mismatches (p = 0.007).

CONCLUSION

Our data suggest that it is previous pregnancy, and not sex per se, that is associated with an increased frequency of rejection in females after heart transplantation.

[Perinatal perspective in heart disease and pregnancy. Review of 1169 cases of pregnancy]

OBJECTIVE

To determinate the effect of maternal heart disease on pregnancy outcome.

METHODS

We reviewed retrospectively 1169 pregnancies in 1093 women with heart disease. 53 women were assisted during 2 pregnancies, ten during 3 and one during 4 pregnancies. All the pregnancies were prenatal and labor assisted at the National Institute of Perinatology, México, D.F.

RESULTS

In 705 (60.30%) the heart disease was of rheumatic origin, in 387 (33.10%) congenital and the remaining were a miscellaneous group. Mitral stenosis and mitral regurgitation (42.13%) was the commonest rheumatic cardiac lesion associated with pregnancy. Ventricular septal defect was seen in the 32.81%. 124 women had a heart valve prosthesis (87 mechanical and 40 bioprosthesis [3 women with double heart valve prosthesis]). Intrauterine fetal growth retardation was the commonest complication. (7.52%) in 29 cases were present complications of heart disease in pregnancy. The abortion was present in 30 cases and intrauterine fetal death in 7 cases. There were 977 term pregnancies. The caesarean section rate was 32.5 per cent, most of them were performed for obstetric or fetal indications. The neonatal weight had a average of 2864.4 +/- 526.9 grams. There were eight maternal deaths in this series (five with congenital origin and 3 rheumatic). The incidence of low birth weight was 8.46 per cent. There were two babies born with cardiac congenital malformations.

[Retrospective epidemiological study of pregnancy complicated by heart disease during 15 years in Shanghai]

OBJECTIVE

To investigate the changes of pregnancy complicated by heart disease.

METHOD

Clinical data of hospitalized pregnant women with heart disease, collected from 10 teaching hospitals in Shanghai during 1981-1995, were analysed retrospectively.

RESULTS

2,680 of 379,065 deliveries (0.71%) were complicated by heart disease during that period. There were a total of 121 maternal deaths, 15 of them due to heart disease, the mortality of heart disease was 0.56%, and the percentage in total maternal deaths was 12.40%. The incidence and mortality rates were similar in 1981-1985, 1986-1990, 1991-1995, but the percentage due to heart disease increased after the late 1980s. The rates of congenital heart disease increased and rhumatic heart disease decreased apparently, the ratio of the former to the latter was 1.76:1. The pregnancy induced hypertension heart disease, the peripartum cardiomyopathy and the miscellaneous heart disease all increased obviously during the 1990s. The heart functions of grade I and II accounted for a considerable proportion (85.45%), but the grade IV tended to increase during the 1990s. Heart failure occurred in 172 cases, with an incidence of 7.6%. The perinatal mortality rate was 7.76%. Cesarean sections were often performed in heart disease women.

CONCLUSION

Pregnancy complicated by heart disease is still one of the major cause of maternal deaths up till now. More effective management should be adopted.

Cardiac disease during pregnancy--a Free State perspective on maternal morbidity and mortality

AIM

Description of maternal outcome of pregnancies complicated by cardiac disease.

SETTING

Pelonomi Hospital, Bloemfontein.

POPULATION

Black African women of low socio-economic background who presented with cardiac disease during pregnancy.

SAMPLE

All patients who delivered from 1 January 1990 to 1 January 1995.

DESIGN

Descriptive retrospective study.

RESULTS

Cardiac disease complicated 0.6% of pregnancies. Rheumatic valvular disease dominated in this population. The maternal mortality rate was 9.5% while the maternal morbidity rate ranged from 50% to 100% for the various lesions.

CONCLUSIONS

Cardiac disease in pregnancy has high maternal mortality and morbidity rates. Hypertension, anticoagulation therapy, late referrals and inadequate counselling were important contributing factors. A high priority should be given to meticulous contraceptive counselling in patients with cardiac disease. Collaboration between obstetricians, physicians and cardiothoracic surgeons in imperative.

Outcome of pregnancy in women with Marfan's syndrome

OBJECTIVE

To improve life expectancy and prevent premature mortality in women with Marfan's syndrome.

METHODS

During the development of a regional genetic register for Marfan's Syndrome the outcome of 91 pregnancies in 36 women with this condition was established retrospectively and the cardiovascular and obstetric complications documented.

RESULTS

No patient had a significant cardiovascular abnormality limiting function before her pregnancy. Of 36 women, four had an aortic dissection relating to pregnancy and two others required aortic surgery following delivery. Thirty women had uncomplicated gestational histories. The incidence of obstetric complications did not exceed expectation.

CONCLUSIONS

Women with Marfan's syndrome are at significant risk of aortic dissection in pregnancy even in the absence of preconceptional cardiovascular abnormality. Aortic root dilatation may be a predictor of risk but dissection may occur without significant dilatation. Guidelines for obstetric care are suggested and preconceptional assessment recommended.

Thromboembolism in pregnancy: an overview

Thromboembolism is a major cause of maternal mortality. Recent advances in the management of thromboembolism in pregnancy include the discovery of a new, inherited thrombophilia, an improved understanding of the indications for thromboprophylaxis, and the increased use of low-molecular-weight heparin instead of unfractionated heparin.

Spontaneous hepatic hemorrhage associated with pregnancy. Treatment by hepatic arterial interruption

OBJECTIVE

The authors determined the effectiveness of hepatic arterial interruption in treating patients with spontaneous hepatic hemorrhage associated with pregnancy.

BACKGROUND DATA

This rare syndrome frequently is seen with eclampsia/preeclampsia and is associated with high maternal mortality. The recommended treatment has been the use of local hemostatic measures.

METHODS

The authors reviewed their experience managing eight patients by hepatic arterial interruption.

RESULTS

Operative hepatic artery ligation was the initial method of controlling hepatic hemorrhage in three patients. One patient recovered, a hepatic sequestrum developed in one, and one patient died. Three patients survived after hepatic arterial embolization, but a sequestrum developed in one. Two patients died when hepatic arterial interruption was used after failed local hemostatic measures.

CONCLUSIONS

The authors believe that hepatic arterial interruption is the preferred treatment for spontaneous hepatic hemorrhage associated with pregnancy. If the diagnosis is made at the time of cesarean section delivery, operative hepatic arterial ligation is indicated. If the diagnosis is made postpartum, percutaneous angiographic embolization should be performed.

Failure of adjusted doses of subcutaneous heparin to prevent thromboembolic phenomena in pregnant patients with mechanical cardiac valve prostheses

OBJECTIVES

This report describes our experience with the use of an anticoagulant regimen of adjusted doses of subcutaneous heparin during pregnancy in women with cardiac valve prostheses.

BACKGROUND

Gravid patients with prosthetic heart valves require long-term anticoagulant therapy. To avoid the increased incidence of fetal morbidity and mortality associated with the use of coumarin agents in such patients during pregnancy, anticoagulation with subcutaneous heparin has been suggested. Controversy exists concerning the appropriate treatment of these patients.

METHODS

Forty pregnancies in 37 women with prosthetic heart valves were prospectively followed up. Subcutaneous heparin was administered from the 6th until the end of the 12th week and in the last 2 weeks of gestation. Heparin was given every 8 h in the first 36 cases and every 6 h in the last 4 cases, and the dose adjusted to maintain the activated partial thromboplastin time at 1.5 to 2.5 times the control level. Acenocoumarol was used at other times.

RESULTS

The incidence rate of spontaneous abortions was 37.5%; there was one neonatal death (2.5%) due to cerebral hemorrhage. No signs of coumarin-induced embryopathy were found in any of the 16 live-born infants studied by the geneticist. One mother died of gastrointestinal bleeding while receiving oral anticoagulant agents. There were two cases of fatal massive thrombosis of a mitral tilting-disk prosthesis during heparin therapy. The study was interrupted after the last of these two cases.

CONCLUSIONS

The regimen of adjusted doses of subcutaneous heparin used in this study is not effective to prevent thrombosis of mechanical valve prostheses during pregnancy. The use of heparin from the 6th to the 12th week of gestation does not decrease the high incidence of fetal wastage associated with anticoagulant therapy. Coumarin agents provide adequate protection against thromboembolism during pregnancy in patients with mechanical valve prostheses.

[Analysis of maternal and fetal risk in 594 pregnancies with heart disease]

The purpose of this study was to estimate the risk of heart diseases in pregnancy. A total of 594 patients with heart diseases treated at the National Cardiovascular Center between 1982 and 1993 were evaluated. The heart diseases were classified into eight categories: congenital heart disease with or without pulmonary hypertension (8 cases (1%) and 219 cases (37%), respectively), mitral valve prolapse (38 cases (6%)), valvular heart disease with or without valve replacement (9 cases (2%) and 54 cases (9%), respectively), arrhythmia (222 cases (37%)), cardiomyotitis (15 cases (3%)) and miscellaneous (29 cases (5%)). Maternal risk was estimated from the incidence of maternal mortality and artificial preterm delivery. Maternal death within two years after delivery was observed in 7 cases (1.2%): 4 cases with cardiomyotitis (3 DCM and 1 HCH), 2 cases with heart disease with pulmonary hypertension (1 PPH and 1 PDA), and a single case with valvular heart disease with aortic valve replacement. Artificial preterm delivery was carried out in 32 cases (5.4%), most frequently in cases with congenital heart disease with pulmonary hypertension (6/8, 75%) which follows cardiomyotitis (4/15, 27%) and cases with valvular heart disease with valve replacement (2/9, 22%). Fetal risk was measured by the incidence of fetal death, fetal growth retardation and congential heart disease of the fetus. IUFD because of maternal heart disease was observed in 4 cases: two cases with valvular heart disease with valve replacement, a single case with Marfan's syndrome and a single case with DCM. Fetal growth retardation was observed in 59 cases, most frequently in cases with congenital heart disease with pulmonary hypertension and cases with valvular heart disease with valve replacement (3/8 (38%) and 3/9 (33%), respectively). Neonatal congenital heart disease was found in 8 of 228 neonates (3.5%) whose mothers also had congenital heart disease. It is therefore suggested that intensive medical care be recommended in pregnancies complicated with congenital heart disease with pulmonary hypertension or with valvular heart disease with valve replacement, which increase both maternal and fetal risk, and in pregnancies complicated with cardiomyotitis which significantly increases the maternal risk.

Is antenatal care effective in reducing maternal morbidity and mortality?

Women in developing countries are dying from simple preventable conditions but what impact can the procedures collectively called antenatal care having in reducing maternal mortality and morbidity? More importantly what is antenatal care? This review found that questions have been raised about the impact of antenatal care (specifically on maternal mortality) since its inception in developed countries, and that although the questions continue to be asked there is very little research trying to find answers. Many antenatal procedures are essentially screening tests yet it was found that there were very few results showing sensitivity and specificity, and that they rarely complied with the established criteria for the effectiveness of a screening test. The acknowledged gold standard measurement of effectiveness is the randomized controlled trial, yet the only results available referred to nutritional supplementation. This service of flawed methodology has been exported to developing countries and is being promoted by WHO and other agencies. This paper argues that there is insufficient evidence to reach a firm decision about the effectiveness of antenatal care, yet there is sufficient evidence to cast doubt on the possible effect of antenatal care. Research is urgently required in order to identify those procedures which ought to be included in the antenatal process. In the final analysis the greatest impact will be achieved by developing a domiciliary midwifery service supported by appropriate local efficient obstetric services. That this domiciliary service should provide care for women in pregnancy is not disputed but the specific nature of this care needs considerable clarification.

Cardiopulmonary bypass in pregnancy

The cardiopathic patient can sustain acute heart failure during pregnancy. In such cases, if open heart operation is necessary to save the patient's life, the fetus could be seriously compromised after exposure to cardiopulmonary bypass. From 1958 to 1992, 69 reports of cardiac operations during pregnancy with the aid of cardiopulmonary bypass have been published. Maternal mortality was 2.9%. Embryofetal mortality was 20.2%. Examining only the last 40 patients, maternal and embryofetal mortality were 0.0% and 12.5%, respectively. Embryofetal mortality was 24.0% when hypothermia was used, compared with 0.0% while operating in normothermia. Maternal mortality did not change. The use of hypothermia during cardiopulmonary bypass provoked uterine contractions in several patients. Hypothermia decreases O2 exchange through the placenta. Pump flow and mean arterial pressure during cardiopulmonary bypass seem to be the most important parameters that influence fetal oxygenation. We speculate that cardiac operation is not a contraindication to pregnancy prolongation.

Death rates from ischemic heart disease in women with a history of hypertension in pregnancy

BACKGROUND

Evidence about the influence of hypertension in pregnancy on later health and in particular the risk of cardiovascular disorders is conflicting, although a link has been suggested. In a population-based study with a long follow-up time the potential association between hypertension in pregnancy, preeclampsia and eclampsia with increased death rates from ischemic heart disease (IHD) was investigated.

METHODS

All 7543 case records at the main maternity hospital in Iceland during 1931-1947 were reviewed to identify women with hypertension in pregnancy, subdivided by parity and severity of disease into those with eclampsia, preeclampsia and hypertension alone. Information on those who had died was obtained from death certificates, supplemented by autopsy reports and hospital records. Death rates from IHD were compared to population data from public health and census reports during corresponding periods and between study groups.

RESULTS

Of 374 hypertensive women 177 had died. The death rate was slightly higher among women with any hypertension in pregnancy than in the reference population (RR = 1.20; 95% CI 1.01-1.42). About half of the increase was attributed to excess mortality from IHD with a relative risk of dying of 1.47 (95% CI 1.05-2.02). The relative risk of dying from IHD was significantly higher among eclamptic women (RR = 2.61; 95% CI 1.11-6.12) and those with preeclampsia (RR = 1.90; 95% CI 1.02-3.52) than those with hypertension alone. Parous women at the index pregnancy had a twofold higher risk of dying from IHD than primigravid women (RR = 2.05; 95% CI 1.19-3.55; p = 0.01).

CONCLUSION

There is an indication of increased death rates among women with a history of hypertension in pregnancy, where ischemic heart disease may be more common than in the general population.

Maternal deaths in Bloemfontein, South Africa--1986-1992

OBJECTIVE

Determination of the maternal mortality ratio and the main causes of maternal death.

SETTING

Pelonomi Hospital, a tertiary care and referral hospital in Bloemfontein.

METHODS

Review of prospectively completed structured questionnaires on all maternal deaths from 1986 to 1992.

RESULTS

The maternal mortality ratio at our institution was 171 per 100 000 live births. Haemorrhage (25%), infection (24%) and hypertensive disease (18%) were the most important causes of death. Seventy-one per cent were direct obstetric deaths and 23% indirect; in the remaining 6%, the cause was uncertain. Of all deaths, 35% were considered preventable.

CONCLUSIONS

The maternal mortality ratio has decreased since our previous report for the period 1980-1985, and haemorrhage has replaced infection as the leading cause of death.