Outcome of pregnancy in women with valve prostheses

Anticoagulant Therapy in Pregnant Women with Mechanical Heart Valves: Italian Federation of Centers for Diagnosis and Surveillance of the Antithrombotic Therapies (FCSA) Position Paper

The management of anticoagulant therapy in pregnant women with mechanical heart valves (MHVs) is difficult and often challenging even for clinicians experienced in the field. These pregnancies, indeed, are burdened with higher rates of complications for both the mother and the fetus, compared to those in women without MHVs. The maternal need for an optimal anticoagulation as provided by vitamin K antagonists is counterbalanced by their teratogen effect on the embryo and fetus. On the other hand, several concerns have been raised about the efficacy of heparins in pregnant women with MHVs, considering the high risk of thrombotic complications in these patients. Therefore, numerous clinical issues about the management of pregnant women with MHVs remain unanswered, such as the selection of the best anticoagulant agent, the optimal anticoagulation levels to be achieved and maintained, and the evaluation of long-term effects for both the mother and the fetus. Based on a comprehensive review of the current literature, the Italian Federation of the Centers for the Diagnosis and the Surveillance of the Antithrombotic Therapies (FCSA) proposes experience-based suggestions and expert opinions. Particularly, this consensus document aims at providing practical guidance for clinicians dealing with pregnant women with MHVs, to optimize maternal and fetal outcomes while guaranteeing adequate anticoagulation. Finally, FCSA highlights the need for the creation of multidisciplinary teams experienced in the management of pregnant women with MHVs during pregnancy, delivery, and postpartum, in order to better deal with such complex clinical issues and provide a comprehensive counseling to these patients.

A Case Report of Secondary Postpartum Hemorrhage in a Pregnant Woman With a Mechanical Mitral Valve: Challenges of Anticoagulation

A pregnant woman with rheumatic heart disease always runs the risk of developing both thromboembolic and hemorrhagic symptoms, necessitating careful monitoring of her anticoagulation treatments both throughout pregnancy and after delivery. Postpartum haemorrhage, a hemorrhagic manifestation, can be challenging to control and presents a significant challenge when it comes to beginning anticoagulation after delivery. Thus, pregnancy in these patients is an extremely risky endeavour. Given that these women take anticoagulants, managing these women with artificial heart valves throughout pregnancy can be difficult. The diminished clotting ability in these women may be the cause of postpartum haemorrhage, and a multidisciplinary approach is necessary for a successful treatment. To manage this potentially fatal illness, a well-equipped institution with proper support systems is essential. We present a 23-year-old primigravida who was 39 weeks and three days pregnant and had a repaired aortic valve as well as a prosthetic mitral valve. She was taking warfarin to prevent clotting when she was pregnant.

A Study of Fertility and Pregnancy Outcomes in Women after Surgery for Valvular Heart Disease

Objectives:

Chronic Rheumatic Heart Disease (CRHD)is a common condition in India. CRHD accounts for a majority of heart valve surgery, including those in the younger age group. These young women almost traditionally get married in a country like India, and the social pressure to bear children is tremendous. Anticoagulation and the postoperative state of the patient itself can be a risk factor for maternal and fetal outcomes. There is very little data available for the same in India.

Materials and Methods:

In this study, 100 cases were studied retrospectively to study the fertility patterns after valvular heart surgery including fetal outcomes. This study was conducted at Nizam’s Institute of Medical Sciences, Hyderabad in which pregnancy, anticoagulation, maternal and fetal outcomes were studied.

Results:

A total of 63 patients conceived after surgery (pregnancy rate = 63%/ failure rate =37%) (p=0.001). Fetal loss occurred in 6 of the pregnancies, due to spontaneous abortion (n=3) and medical abortion (n=3). Parity, associated conditions and age did not affect the outcome. During pregnancy, 28 patients switched to UF heparin, 31 stayed on warfarin, 4 did not take any anticoagulation. Fetal loss was observed in 3 patients on Warfarin during pregnancy and 3 on UF heparin. Maternal loss was observed in 4 patients out of which 2 were on Warfarin, 1 on unfractionated UF heparin and 1 did not take any anticoagulation during pregnancy. In comparison, warfarin and UF heparin had similar fetal outcomes.

Conclusion:

The study recorded good outcomes irrespective of type of prosthesis and anticoagulation.

Successful management of postpartum hemorrhage and surgical site infection in a pregnant woman under warfarin for heart valve replacement: A case report

INTRODUCTION AND IMPORTANCE

Pregnant women under warfarin for mechanical heart valves can pose a variety of challenges which requires fine tuning of various anticoagulants throughout the pregnancy and in the postpartum period as hemorrhage can lead to maternal and fetal morbidity and mortality.

CASE PRESENTATION

A 36-year-old woman gravida two, para one at 35 weeks 5 days gestation, with hypothyroidism with mitral valve replacement and tricuspid valve repair due to rheumatic heart disease underwent emergency lower section cesarean section for fetal bradycardia. B-lynch suturing was eventually done to control atonic postpartum hemorrhage. During hospital stay she developed surgical site infection of abdominal skin incision site which was also subsequently managed. Postpartum anticoagulation was started late due to postpartum hemorrhage and finally the patient was discharged on warfarin.

CLINICAL DISCUSSION

There is always a risk of both thromboembolic and hemorrhagic manifestations in a pregnant woman with a prosthetic heart valve which requires fine tuning of anticoagulants throughout the pregnancy and in the postpartum period. Hemorrhagic manifestation in the form of postpartum hemorrhage is common which can be difficult to manage and also poses a great dilemma in restarting the anticoagulation after delivery. Excessive blood loss can itself lead to mortality and morbidity, and also via increased risk of surgical site infection.

CONCLUSION

Appropriate preconception counseling along with meticulous assessment, management and monitoring of pregnant women with prosthetic heart valves is necessary to decrease fetal and maternal morbidity and mortality.

Thrombosis of mechanical mitral valve prosthesis during pregnancy: An ongoing "saga" in need of comprehensive solutions

Emergency treatment for thrombosed mechanical valve prothesis during pregnancy is not uncommon in low- and middle-income countries. The presence of a mechanical valve continues to be an important cause of maternal morbidity and mortality. There is a pressing need for increasing awareness and feasible solutions for this huge problem. We here describe four patients who needed emergency treatment for thrombosis of mechanical valve prothesis during pregnancy and review the evolving comprehensive strategies for dealing with this issue.

Management of Anticoagulation in Pregnant Women With Mechanical Heart Valves

Importance

Mechanical heart valves (MHVs) pose significant thrombogenic risks to pregnant women and their fetuses, yet the choice of anticoagulation in this clinical setting remains unclear. Various therapeutic strategies carry distinct risk profiles that must be considered when making the decision about optimal anticoagulation.

Objective

We sought to review existing data and offer recommendations for the anticoagulation of pregnant women with MHVs, as well as management of anticoagulation in the peripartum period.

Evidence Acquisition

We performed a literature review of studies examining outcomes in pregnant women receiving systemic anticoagulation for mechanical valves, and also reviewed data on the safety profiles of various anticoagulant strategies in the setting of pregnancy.

Results

Warfarin has been shown to increase rates of embryopathy and fetal demise, although it has traditionally been the favored anticoagulant in this setting. Low-molecular-weight heparin, when dosed appropriately with close therapeutic monitoring, has been shown to be safe for both mother and fetus.

Conclusions

We favor the use of low-molecular-weight heparin with appropriate dosing and monitoring for the anticoagulation of pregnant women with MHVs. Data suggest that this approach minimizes the thrombotic risk associated with the valve while also providing safe and effective anticoagulation that can be easily managed in the peripartum period.

Valvular Heart Disease in Pregnancy: Anticoagulation and the Role of Percutaneous Treatment

Valvular heart disease is present in about 1% of pregnancies, and it poses a management challenge as both fetal and maternal lives are at risk of complications. Pregnancy is associated with significant hemodynamic changes, which can compromise the cardiac status in women with underlying valvular disorders. Management of valvular heart diseases has undergone considerable innovation and advancement with newer techniques, approaches and devices being employed. The decision regarding the management of anticoagulation, especially in patients with prosthetic valves, raises distinct questions and challenges. In this review, we describe the management of common valvular heart diseases encountered during pregnancy, role of percutaneous catheter based therapeutic interventions, the importance of a team-based approach, and the challenges given existing gaps in the literature.

High-Versus Low-Dose Warfarin-Related Teratogenicity: A Case Report and Systematic Review

OBJECTIVE

The optimal anticoagulant therapy during pregnancy in women with mechanical heart valves remains controversial. This study highlights a case of high-dose warfarin ingestion throughout pregnancy and performed a systematic review to assess rates of teratogenicity with high versus low warfarin dosing (≤5 mg daily).

METHODS

A literature search for all case reports and available literature was conducted in PubMed, Medline, and EMBASE up to December 2016 using medical subject heading terms "mechanical prosthetic valves," "pregnancy," "oral anticoagulants," "warfarin," "coumarins," "heparin, low-molecular-weight," and "thromboembolism." To be included, warfarin had to be administered anytime between 6 and 12 weeks of gestation with the dose being specified. The Newcastle-Ottawa Scale was used to assess quality of the cohort data.

RESULTS

The woman in the studied case received the highest reported warfarin doses throughout pregnancy (14.5-16.5 mg daily) and delivered a baby with no evidence of teratogenicity to the current age of 5 years. The study identified 23 case reports, with all demonstrating warfarin teratogenicity regardless of high-dose (n = 12) or low-dose (n = 11) warfarin. Twelve cohort studies identified a warfarin teratogenicity rate of 5.0%, with rates of 2.4% and 10.5% with low- and high-dose warfarin, respectively. Risk of bias was moderate (median Newcastle-Ottawa Scale score of 6) for all of the cohort studies.

CONCLUSION

Although a lower prevalence of warfarin-induced teratogenicity is reported with low-dose warfarin, a safe "cut-off" dose is misleading. Teratogenic risk with warfarin is unpredictable, mandating individual decisions regardless of the dose.

Anticoagulation in venous Thrombosis

Major studies addressing various aspects of the treatment of deep vein thrombosis are reviewed. It has lately been demonstrated that heparin should be dosed according to body weight and is preferably given as subcutaneous injections twice daily. Alternatively, low-molecular-weight heparins may be given in a fixed dose once daily, which does not require monitoring. Oral anticoagulation should be started concomitantly with heparin and targeted at an international normalized ratio of 2.0-3.0. This treatment should continue for a longer duration than previously accepted, in many cases for 6 months. For patients with contraindications to oral anticoagulation, secondary prophylaxis with a low-molecular-weight heparin is also effective and safe.

Anticoagulation therapy in pregnant women with mechanical heart valve

Background

This study aims to investigate the effects of various anticoagulant regimens on prosthetic valve-related complications and pregnancy outcomes including feto-maternal mortality and morbidity, and to identify the most optimal anticoagulation therapy regimen.

Methods

Anticoagulant therapy regimens for pregnant women who underwent mechanical heart valve replacement between January 1990 and December 2015 was analyzed retrospectively. Seventy-two pregnancies among 57 patients after mechanical heart valve replacement were reviewed, and four different regimens were identified and evaluated during different trimesters of pregnancy.

Results

Forty of 72 pregnancies resulted in healthy newborns; 35 (48.6%) healthy neonates, four (5.6%) premature births, and one (1.4%) low birth weight. Eighteen (25%) therapeutic and 12 (16.7%) spontaneous abortions, as well as two (2.8%) stillbirths occurred. Seven valve thromboses developed during pregnancy or the postpartum period. Bleeding occurred in six patients (10.5%) and peripheral embolism also occurred in six patients (10.5%). No maternal mortalities were recorded.

Conclusion

Although there is no consensus on the most optimal anticoagulant regimen during pregnancy, substituting warfarin with dose-adjusted unfractionated heparin or low-molecularweight heparin seems suitable to prevent teratogenicity and a high abortion rate in the first trimester. Low-molecular-weight heparin is practical to use and can be monitored reliably, resulting in successful pregnancy outcomes. However, warfarin throughout pregnancy ≤5 mg per day may be an alternative choice, if the risk of embryopathy is accepted by the pregnant woman.

Adult Congenital Heart Disease with Pregnancy

The number of women with congenital heart disease (CHD) at risk of pregnancy is growing because over 90% of them are grown-up into adulthood. The outcome of pregnancy and delivery is favorable in most of them provided that functional class and systemic ventricular function are good. Women with CHD such as pulmonary hypertension (Eisenmenger syndrome), severe left ventricular outflow stenosis, cyanotic CHD, aortopathy, Fontan procedure and systemic right ventricle (complete transposition of the great arteries [TGA] after atrial switch, congenitally corrected TGA) carry a high-risk. Most frequent complications during pregnancy and delivery are heart failure, arrhythmias, bleeding or thrombosis, and rarely maternal death. Complications of fetus are prematurity, low birth weight, abortion, and stillbirth. Risk stratification of pregnancy and delivery relates to functional status of the patient and is lesion specific. Medication during pregnancy and post-delivery (breast feeding) is a big concern. Especially prescribing medication with teratogenicity should be avoidable. Adequate care during pregnancy, delivery, and the postpartum period requires a multidisciplinary team approach with cardiologists, obstetricians, anesthesiologists, neonatologists, nurses and other related disciplines. Caring for a baby is an important issue due to temporarily pregnancy-induced cardiac dysfunction, and therefore familial support is mandatory especially during peripartum and after delivery. Timely pre-pregnancy counseling should be offered to all women with CHD to prevent avoidable pregnancy-related risks. Successful pregnancy is feasible for most women with CHD at relatively low risk when appropriate counseling and optimal care are provided.

Echocardiography in Pregnancy: Part 2

The prevalence of pregnant women with cardiovascular heart disease is increasing. Transthoracic echocardiography is safe during pregnancy, and it is an important diagnostic tool in pregnant women with established heart disease in order to monitor ventricular and valvular anatomy and function. In addition, it can be used to delineate cardiac anatomy in complex congenital heart disease and help stratify maternal risk during pregnancy. This review will focus on the use of echocardiography in the diagnosis and management of pregnant women with common congenital lesions and with prosthetic valves.

Anesthesia in pregnancy with heart disease

Management of pregnant women with heart disease remains challenging due to the advancement of innovations in cardiac surgery and correction of complex cardiac anomalies, and more recently, with the successful performance of heart transplants, cardiac diseases are not only likely to coexist with pregnancy, but will also increase in frequency over the years to come. In developing countries with a higher prevalence of rheumatic fever, cardiac disease may complicate as many as 5.9% of pregnancies with a high incidence of maternal death. Since many of these deaths occur during or immediately following parturition, heart disease is of special importance to the anesthesiologist. This importance arises from the fact that drugs used for preventing or relieving pain during labor and delivery exert a major influence - for better or for worse - on the prognosis of the mother and newborn. Properly administered anesthesia and analgesia can contribute to the reduction of maternal and neonatal mortality and morbidity.

Management of Pregnancy in Patients With Complex Congenital Heart Disease: A Scientific Statement for Healthcare Professionals From the American Heart Association

Today, most female children born with congenital heart disease will reach childbearing age. For many women with complex congenital heart disease, carrying a pregnancy carries a moderate to high risk for both the mother and her fetus. Many such women, however, do not have access to adult congenital heart disease tertiary centers with experienced reproductive programs. Therefore, it is important that all practitioners who will be managing these women have current information not only on preconception counseling and diagnostic evaluation to determine maternal and fetal risk but also on how to manage them once they are pregnant and when to refer them to a regional center with expertise in pregnancy management.

Anticoagulation in Pregnant Women With Prosthetic Heart Valves

Background: Pregnancy is associated with an increased risk of thrombosis in women with mechanical prosthetic heart valves. Effective anticoagulation is therefore critical in such patients but remains problematic, since oral anticoagulation and both unfractionated and low-molecular-weight heparin may be associated with important fetal and maternal side effects.

Purpose: To review information related to the use of anticoagulation with both warfarin and heparin and reassess the safety and efficacy of these therapies in pregnant women with mechanical prosthetic heart valves.

Data source and selection: A MEDLINE search from 1966 to October 2003 for English and non-English language articles that reported the use of anticoagulation in pregnancy was conducted. Articles were included if they reported use of anticoagulation in pregnancy with emphasis on those that included women with mechanical prosthetic heart valves.

Conclusions: Anticoagulation prophylaxis with both warfarin and heparin (unfractionated heparin and low-molecular-weight heparin) may be associated with important fetal and maternal side effects. Optional regimens for the treatment of low-risk and high-risk patients are proposed to minimize potential complications.

Prosthetic Cardiac Valve Replacement: Management Problems

Altered states of coagulability can be precarious for patients with valvular prostheses. Prosthetic valvular thrombosis can produce devastating hemodynamic changes wherein surgical intervention might be high risk. We describe the cases of 4 patients with prosthetic cardiac valve replacements to highlight some of the problems that might be encountered. The first patient suffered prosthetic valve thrombosis following withdrawal of her anticoagulants during labor. She was treated with urokinase but failed to survive. The second young female suffered two episodes of valvular thrombosis and was successfully treated with streptokinase on the first occasion but succumbed one year later during the second episode. The third patient was an elderly male who suffered an intracerebral hemorrhage as a result of an increase in anticoagulant dosage. He was successfully managed with low molecular weight heparin. In the fourth case, a young female with a prosthetic mitral valve had a favorable clinical outcome in spite of withdrawal of anticoagulants during labor.

Impact of Ross Operation on Outcome in Young Female Adult Patients Wanting to Have Children

BACKGROUND

The most appropriate valve substitute at aortic valve replacement (AVR) for young female adult patients wanting to have children is unclear.

METHODS AND RESULTS

Between 1992 and 2013, 12 consecutive female patients aged >18 (median, 22.5 years; range, 18-34 years) underwent Ross operation (Ross group). Between 1984 and 2013, 9 consecutive female patients aged >18 (median, 30 years; range, 22-39 years) underwent AVR with bioprosthesis (bioprosthesis group). There was 1 late mortality in the bioprosthesis group, due to prosthetic valve endocarditis (PVE). Freedom from reoperation for aortic valve at 15 years was 90.0% in the Ross group, and 57.1% in the bioprosthesis group (log-rank, P=0.098). One in the Ross group underwent reoperation for aortic regurgitation (AR), whereas 4 in the bioprosthesis group did so for aortic stenosis (AS) in 2, combined AS and AR in 1, and PVE in 1. Five patients in the Ross group and 3 in the bioprosthesis group had 7 and 4 uneventful pregnancies, respectively. AR progressed during the perinatal period in a total of 7 of 11 pregnancies. No AS was seen at discharge, after 5 years, or during pregnancy in the Ross group.

CONCLUSIONS

The long-term outcome of Ross operation for female patients wanting to have children is excellent. Although subclinical pulmonary autograft valve regurgitation during pregnancy was often observed, pulmonary autograft stenosis did not occur, therefore it would be an ideal option for patients wanting to have children.

Heart valve prostheses in pregnancy: outcomes for women and their infants

BACKGROUND

As the prognosis of women with prosthetic heart valves improves, an increasing number are contemplating and undertaking pregnancy. Accurate knowledge of perinatal outcomes is essential, assisting counseling and guiding care. The aims of this study were to assess outcomes in a contemporary population of women with heart valve prostheses undertaking pregnancy and to compare outcomes for women with mechanical and bioprosthetic prostheses.

METHODS AND RESULTS

Longitudinally linked population health data sets containing birth and hospital admissions data were obtained for all women giving birth in New South Wales, Australia, 2000-2011. This included information identifying presence of maternal prosthetic heart valve. Cardiovascular and birth outcomes were evaluated. Among 1 144 156 pregnancies, 136 involved women with a heart valve prosthesis (1 per 10 000). No maternal mortality was seen among these women, although the relative risk for an adverse event was higher than the general population, including severe maternal morbidity (139 versus 14 per 1000 births, rate ratio [RR]=9.96, 95% CI 6.32 to 15.7), major maternal cardiovascular event (44 versus 1 per 1000, RR 34.6, 95% CI 14.6 to 81.6), preterm birth (183 versus 66 per 1000, RR=2.77, 95% CI 1.88 to 4.07), and small-for-gestational-age infants (193 versus 95 per 1000, RR=2.03, 95% CI 1.40 to 2.96). There was a trend toward increased maternal and perinatal morbidity in women with a mechanical valve compared with those with a bioprosthetic valve.

CONCLUSIONS

Pregnancies in women with a prosthetic heart valve demonstrate an increased risk of an adverse outcome, for both mothers and infants, compared with pregnancies in the absence of heart valve prostheses. In this contemporary population, the risk was lower than previously reported.

Management of Anticoagulant Therapy for Patients with Prosthetic Heart Valves or Atrial Fibrillation

There is a wide array of recommendations for the management of anticoagulant therapy in patients with mechanical heart valves. Especially the optimal intensity of vitamin K antagonists (VKA) is a ongoing matter of debate. On the basis of several studies, recommendations for daily clinical practice can be made. In this review, we discussed the studies and the different guidelines. Guidelines for the prevention of thromboembolic complications in patients with atrial fibrillation are more stringent. VKA with a target INR between 2.0 and 3.0 is more effective in the prevention of stroke than aspirin, especially in the presence of riskfactors for thromboembolism (age above 65, previous thromboembolism, history of hypertension and diabetes, enlarged left atrial diameter and left ventricular dysfunction). In the absence of clinical or echocardiographical riskfactors for thromboembolism, patients may be safely treated with aspirin.

Pregnancy outcomes in women with aortic valve substitutes

Young women who require aortic valve replacement need information on the potential cardiac and obstetric complications of pregnancy for the different valve substitutes available. We, therefore, assessed the pregnancy outcomes in women who had received an autograft, homograft, or mechanical valve in the aortic position. Women who were pregnant after surviving aortic valve replacement at our institution from 1987 to 2011 were included. Information on cardiac status and pregnancy outcome was obtained through the hospital medical records and by an extensive patient questionnaire. A total of 40 women experienced 67 pregnancies, of which 55 (82%) were completed pregnancies, 6 (9%) were miscarriages, and 6 (9%) were terminated. Of the 40 women, 18 (45%) had a pulmonary autograft, 13 (32%) a homograft, and 9 (23%) a mechanical valve. The mean age at the first pregnancy was 30.0 ± 5.7 years. No maternal mortality but 1 fetal death (1.8%) and 1 neonatal death (1.8%) occurred. Maternal cardiac complications developed in 13% and obstetric complications in 38% of the completed pregnancies. Heart failure (9%), arrhythmias (7%), hypertension-related disorders (7%), preterm delivery (24%), and small-for-gestational-age infants (15%) were most often encountered. Mechanical valve recipients had the greatest incidence of both cardiac and obstetric complications. In conclusion, pregnancy-associated complications after aortic valve replacement were common, and human tissue valves should be considered in the discussion for the optimal aortic valve substitute in a young woman. However, careful obstetric monitoring is mandatory.

Is there a suitable method of anticoagulation in pregnant patients with mechanical prosthetic heart valves?

A best evidence topic was written according to a structured protocol in order to identify the mode of anticoagulation that has the best safety profile for both the mother and the foetus in pregnant patients with mechanical prosthetic heart valves. A total of 281 papers were identified using the reported search, of which eight represented the best evidence to answer the clinical question. The authors, date, journal, study type, population, main outcome measures and results are tabulated. The reported measures were foetal mortality, maternal mortality, congenital abnormalities and embryopathy, and maternal thromboembolic and haemorrhagic complications. The medical orthodoxy has warned of the combination of oral anticoagulation and pregnancy due to the well-documented warfarin embryopathy. Yet only one of the reported papers identified a greater incidence of foetal aberrations among warfarin use, with the highest reported rate being 6.4% and two of the assessed papers reporting no embryopathy at all. Foetal mortality with oral anticoagulation use ranged from 1.52 to 76%. All reported publications demonstrated a superior maternal outcome with warfarin use, with a range of thromboembolic events from 0 to 10% in comparison with 4 to 48% where heparin was used. Thus, it is concluded that warfarin is a more durable anticoagulant with a better maternal outcome despite it carrying a greater foetal risk. Although, in contrast to previous teaching, the risks of embryopathy are not the major drawback of oral anticoagulation. Heparin is consistently less effective, but may be preferred for the superior foetal outcome. Heparin usage during the first trimester reduces the foetal risk but is still associated with an adverse maternal outcome. While the focus for clinicians looking after pregnant women with mechanical heart valves may be to prevent maternal thromboembolic complications, the overriding concern for many women is to avoid any harm to their unborn child, even when this places their health at risk. Thus women with mechanical heart valves must be fully informed of the risks involved with different anticoagulation for an informed decision to be made.

An audit of pregnant women with prosthetic heart valves at a tertiary hospital in South Africa: a five-year experience

BACKGROUND

Cardiac disease in pregnancy is a common problem in under-resourced countries and a significant cause of maternal morbidity and mortality. A large proportion of patients with cardiac disease have prosthetic mechanical heart valve replacements, warranting prophylactic anticoagulation.

AIM

To evaluate obstetric outcomes in women with prosthetic heart valves in an under-resourced country.

METHODS

A retrospective chart review was performed of 61 pregnant patients with prosthetic valve prostheses referred to our tertiary hospital over a five-year period.

RESULTS

Sixty-one (6%) of 1 021 pregnant women with A diagnosis of cardiac disease had prosthetic heart valves. Fifty-nine had mechanical valves and were on prophylactic anticoagulation therapy, three had stopped their medication prior to pregnancy and two had bioprosthetic valves. There were forty-one (67%) live births, two (3%) early neonatal deaths, 12 (20%) miscarriages and six (10%) stillbirths. Maternal complications included mitral valve thrombosis (n = 4), atrial fibrillation (n = 8), infective endocarditis (n = 6), caesarean section wound haematomas (n = 7), broad ligament haematoma (n = 1) and warfarin embryopathy (n = 4). Haemorrhagic complications occurred in five patients and all five required blood transfusions.

CONCLUSION

Prophylactic anticoagulation with warfarin in patients with mechanical heart valve prostheses was associated with high rates of maternal and neonatal complications, including significant foetal wastage in the first and early second trimesters of pregnancy. Health professionals providing care for pregnant women with prosthetic heart valves must consistently advise on family planning matters, adherence to anticoagulation regimes and consider the use of prophylactic anticoagulant regimens other than warfarin, particularly during the first trimester of pregnancy.

Antithrombotic medication for cardioembolic stroke prevention

Embolism of cardiac origin accounts for about 20% of ischemic strokes. Nonvalvular atrial fibrillation is the most frequent cause of cardioembolic stroke. Approximately 1% of population is affected by atrial fibrillation, and its prevalence is growing with ageing in the modern world. Strokes due to cardioembolism are in general severe and prone to early recurrence and have a higher long-term risk of recurrence and mortality. Despite its enormous preventive potential, continuous oral anticoagulation is prescribed for less than half of patients with atrial fibrillation who have risk factors for cardioembolism and no contraindications for anticoagulation. Available evidence does not support routine immediate anticoagulation of acute cardioembolic stroke. Anticoagulation therapy's associated risk of hemorrhage and monitoring requirements have encouraged the investigation of alternative therapies for individuals with atrial fibrillation. New anticoagulants being tested for prevention of stroke are low-molecular-weight heparins (LMWH), unfractionated heparin, factor Xa inhibitors, or direct thrombin inhibitors like dabigatran etexilate and rivaroxaban. The later exhibit stable pharmacokinetics obviating the need for coagulation monitoring or dose titration, and they lack clinically significant food or drug interaction. Moreover, they offer another potential that includes fixed dosing, oral administration, and rapid onset of action. There are several concerns regarding potential harm, including an increased risk for hepatotoxicity, clinically significant bleeding, and acute coronary events. Therefore, additional trials and postmarketing surveillance will be needed.