Dose-dependent fetal complications of warfarin in pregnant women with mechanical heart valves

Combination Anticoagulation Strategy in Pregnancy With Mechanical Valves: The KYBELE Study

BACKGROUND

Optimal first-trimester anticoagulation is still challenging in pregnant women with mechanical heart valves (MHVs) requiring high-dose warfarin.This multicenter prospective study aims to determine the optimal anticoagulation regimens for pregnant patients with MHVs.

METHODS

All women were allocated to one of three treatment options during first trimester including lone low-molecular-weight heparin (LMWH), combination of LMWH+2.5 mg warfarin, and LMWH+4 mg warfarin. Primary maternal outcome included a combination of death, thromboembolism, severe bleeding, and need for treatment of mechanical valve thrombosis (MVT).Any fetal loss was determined as primary fetal outcome.

RESULTS

The study included 78 pregnancies in 65 women with MHVs.Primary maternal outcome rate was 44%, 12.5%, 3.5%, respectively.The rates of primary maternal outcome (44 vs 3.5%, p<0.001), obstructive MVT (16 vs 0%, p=0.04), MVT requiring treatment (28 vs 0%, p=0.003), and cerebral embolism (24 vs 3.4%, p=0.041) were found to be significantly higher in lone LMWH group compared to LMWH+4 mg warfarin group. Moreover, the rates of primary maternal outcome (12.5 vs 44%, p=0.015) and treatment for MHV thrombus (4.2 vs 28%, p=0.049) were significantly lower in LMWH+2.5 mg warfarin group compared to lone LMWH group.The incidences of fetal loss were 8 (32%) in the lone LMWH group, 8 (33.3%) in LMWH+2.5 mg warfarin group, and 11 (37.9%) in LMWH+4 mg warfarin group (p=0.890 for 3-group).Warfarin related-embryopathy was not observed in any case.

CONCLUSIONS

The combined anticoagulation strategy of LMWH plus low-dose warfarin during the first trimester of pregnancy may result in less maternal complications with comparable fetal outcomes in patients with MHVs.

CONDENSED ABSTRACT

Low-molecular-weight heparin (LMWH) is thought to be safer for the fetus, however it is suspected to be less protective for the mother. To solve this dilemma, the authors suggested a novel anticoagulation strategy in pregnant women with prosthetic valves. Seventy-eight pregnancies of 65 women [median age 32 (27-35) years] were included in the study. A combination of LMWH and a reduced dose warfarin were associated with low rates of thrombus-related complications in pregnant patients with mechanical heart valves.

Pregnancy outcomes in Chinese women with mechanical heart valves receiving warfarin treatment throughout pregnancy: 14-year experience

OBJECTIVE

The purpose was to evaluate pregnancy outcomes and risk factors associated with fetal complications in Chinese pregnant women with mechanical heart valves (MHVs) taking low-dose warfarin, aiming to fill in the research gap of this area.

METHODS

Between June 2010 and Aug 2023, 122 patients with MHVs who had 151 pregnancies and received warfarin throughout pregnancy were included. We compared them with 302 paired pregnancies without warfarin treatment. Binary logistic regression analyses were performed to explore risk predictors of fetal complications.

RESULTS

Pregnancy loss rate was 37.1 % in women taking warfarin, compared to only 4.6 % for those without warfarin exposure in pregnancy (RR = 8.00, 95 % CI: 4.61-13.90). In pregnant women with MHVs, there were 34 spontaneous abortions, 22 stillbirths and 1 neonatal malformation. In the first, second and third pregnant trimesters of women with MHVs, fetal complication incidences were 19.2 %, 9.9 % and 8.0 %, respectively. 86.0 % of fetal complications occurred in women taking a warfarin dose ≤5 mg/d, accounting for 94.0 % of the total population. The newborns' birth weight, gestational age and 1-minute Apgar score were significantly lower in pregnancies treated with warfarin compared to those without warfarin exposure. Only 2.0 % of postpartum hemorrhage and no thrombosis or maternal mortality data were collected in pregnant women on warfarin in this study.

CONCLUSION

Most Chinese pregnant women take a warfarin daily dose ≤5 mg and they might have only around 60 % chance of giving birth to a live baby without maternal complications.

Lipid nanoparticle structure and delivery route during pregnancy dictate mRNA potency, immunogenicity, and maternal and fetal outcomes

Treating pregnancy-related disorders is exceptionally challenging because the threat of maternal and/or fetal toxicity discourages the use of existing medications and hinders new drug development. One potential solution is the use of lipid nanoparticle (LNP) RNA therapies, given their proven efficacy, tolerability, and lack of fetal accumulation. Here, we describe LNPs for efficacious mRNA delivery to maternal organs in pregnant mice via several routes of administration. In the placenta, our lead LNP transfected trophoblasts, endothelial cells, and immune cells, with efficacy being structurally dependent on the ionizable lipid polyamine headgroup. Next, we show that LNP-induced maternal inflammatory responses affect mRNA expression in the maternal compartment and hinder neonatal development. Specifically, pro-inflammatory LNP structures and routes of administration curtailed efficacy in maternal lymphoid organs in an IL-1β-dependent manner. Further, immunogenic LNPs provoked the infiltration of adaptive immune cells into the placenta and restricted pup growth after birth. Together, our results provide mechanism-based structural guidance on the design of potent LNPs for safe use during pregnancy.

Pregnancy, delivery and neonatal outcomes in women with a cerebrovascular-accident history prior to delivery - Evaluation of a population database

Objective

Cerebrovascular accidents (CVA) in childbearing-age women are rare. We aimed to evaluate the association between CVA events prior to delivery and obstetrical and neonatal outcomes.

Methods

A retrospective cohort study was conducted using data from the Healthcare Cost and Utilization Project, Nationwide Inpatient Sample (HCUP-NIS) database. All pregnant women who delivered or had a maternal death in the US from 2004 to 2014 were included in the study. We performed a comparison between women with an ICD-9 diagnosis of CVA before the delivery admission and those without. Obstetrical and neonatal outcomes were compared between the two groups.

Results

In total, 9,096,788 women fulfilled the inclusion criteria. Among them, 695 women (7.6 per 100,000) were diagnosed with a CVA before delivery. Women with a history of CVA, compared to those without, were more likely to be Black, older than 35 years of age, and suffer from obesity, chronic hypertension, pregestational diabetes, and thyroid disease. Patients with a prior CVA, compared to those without, had higher rates of pregnancy-induced hypertension (aOR 6.41, 95% CI 5.03-8.39, p < 0.001), preeclampsia (aOR 7.65, 95% CI 6.03-9.71, p < 0.001), and eclampsia (aOR 171.56, 95% CI 124.63-236.15, p < 0.001). Additionally, they had higher rates of preterm delivery (aOR 1.72, 95% CI 1.33-2.22,p = 0.003), cesarean section (aOR 2.69, 95% CI 2.15-3.37, p < 0.001), and maternal complications such as a peripartum hysterectomy (aOR 11.62, 95% CI 5.77-23.41, p < 0.001), postpartum hemorrhage (aOR 3.39, 95 % CI 2.52-4.54, p < 0.001), disseminated intravascular coagulation (aOR 16.32, 95% CI 11.33-23.52, p < 0.001), venous thromboembolism (aOR 45.08, 95% CI 27.17-74.8, p < 0.001), and maternal death (aOR 486.11, 95% CI 307.26-769.07, p < 0.001). Regarding neonatal outcomes, patients with a prior CVA, compared to those without, had a higher rate of intrauterine fetal demise and congenital anomalies.

Conclusion

Women with a CVA event before delivery have a significantly higher incidence of maternal complications, including hypertensive disorders of pregnancy, and neonatal complications, such as intrauterine fetal demise and congenital anomalies. Rates of maternal death were dramatically increased, and this association requires further evaluation.

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.

Pulmonary Thromboembolism in Pregnancy: A Case Report and Literature Review

Data on the optimal diagnostic management of pregnant women with suspected pulmonary embolism are limited. Despite a lack of compelling evidence in some practices, clinical practice guidelines focus on the management of these patients. We present the case of a 24-year-old patient at 36 weeks of pregnancy in whom pulmonary thromboembolism (PTE) was diagnosed in a timely manner also with hemodynamic instability and echocardiographic images with clear involvement of the right cavities. She received thrombolytic therapy with alteplase 100 mg intravenously over 2 hours, which resulted in excellent outcomes for both the pregnant woman and fetus. Understanding the acute approach and management of these patients will improve our clinical practice; therefore, we reviewed a case report of a pregnant patient with high-risk PTE and compared it with current evidence. In conclusion, PE is a common disease with a high mortality rate during pregnancy. Therefore, having made a timely diagnosis using the relevant diagnostic aids and performing thrombolysis with rtPA increase the probability of survival in our patient, leading to successful results for both her and the fetus.

Maternal exposure to heparin products and risk of birth defects in the National Birth Defects Prevention Study

BACKGROUND

Heparin and low-molecular-weight heparin are the preferred anticoagulants during pregnancy as they do not cross the placenta. Although research on the safety of heparin products has been reassuring, previous studies have considered birth defects as a single outcome or by larger organ system and have not examined associations with specific birth defects.

METHODS

We analyzed data from the National Birth Defects Prevention Study, a multisite, population-based case-control study from 1997 to 2011. We used unconditional logistic regression with Firth's penalized likelihood to calculate adjusted odds ratios (ORs) and profile likelihood 95% confidence intervals (CIs) for defects with at least five exposed cases. For defects with 3-4 exposed cases, we estimated crude ORs and exact 95% CIs.

RESULTS

Of the 42,743 women in our analysis, 117 (0.4%) case and 44 (0.4%) control mothers reported using a heparin product in early pregnancy. The adjusted ORs ranged from 0.9 to 3.9 and were elevated for anorectal atresia (OR = 2.0, 95% CI = 0.8-4.3), longitudinal limb deficiency (3.5, 1.3-7.8), transverse limb deficiency (1.8, 0.6-4.3), atrioventricular septal defect (3.9, 1.4-9.0), and secundum atrial septal defect (2.2, 1.2-3.8).

CONCLUSIONS

We observed elevated associations for some birth defects, although heparin is a rare exposure, which limited our ability to evaluate many associations. Future studies that can explore specific birth defects and adequately control for confounding by indication are needed. Given that women with an indication for heparin products during pregnancy often need to take medication, one must remain mindful of the underlying risk of a birth defect that exists regardless of medication use.

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.

The multidisciplinary management of a mechanical mitral valve thrombosis in pregnancy: a case report and review of the literature

Background

The management of anticoagulation for mechanical heart valves during pregnancy poses a unique challenge. Mechanical valve thrombosis is a devastating complication for which surgery is often the treatment of choice. However, cardiac surgery for prosthetic valve dysfunction in pregnant patients confers a high risk of maternofetal morbidity and mortality.

Case summary

A 39-year-old woman in her first pregnancy at 30 weeks gestation presented to hospital with a mechanical mitral valve thrombosis despite therapeutic anticoagulation with low-molecular-weight heparin. She underwent an emergent caesarean section followed immediately by a bioprosthetic mitral valve replacement. This occurred after careful planning and organization on the part of a large multidisciplinary team.

Discussion

A proactive, rather than reactive, approach to the surgical management of a mechanical valve thrombosis in pregnancy will maximize the chances of successful maternal and fetal outcomes.

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.

Medication use during pregnancy and birth defects in Hunan province, China, during 2016-2019: A cross-sectional study

Safety of drug use during pregnancy attracts attentions from clinicians, pregnant woman, and even the total society. However, the studies about medication use during pregnancy and the followed birth defects (BDs) are rare in Chinese. To study condition about medication use during pregnancy and the followed BDs in Hunan province of China, here a cross-sectional study was carried out. All women using medication during pregnancy and delivering fetuses with BDs in Hunan province, China, during 2016 to 2019 were employed in this study. The descriptive analysis was carried out with Excel 2010, and the data analyses were performed by using Chi-Squared test in SPSS 16.0. After filtering, a total of 752 cases were included. In these fetuses, the males are more than females (P < .05). The severe BDs, leading to death or uncorrectable lifelong deformity, were observed for 346 times, and the other (minor) BDs were observed for 593 times. The most used drugs, categorized into pregnancy C, D, or X degrees by food and drug administration (FDA) or pharmaceutical manufacturers, mainly included anti-hyperthyroidism drugs, anti-epilepsy drugs, preventing miscarriage drugs, etc. This population-based data highlight the potential high risks for BDs from the aspect of drug use during pregnancy in Hunan province of China, and drugs with more safety, less kinds, and lower doses should be the better choice for pregnant women.

Management of Contraception in Adolescent Females With Hormone-Related Venous Thromboembolism

PURPOSE

Management of contraception in adolescent females with hormone-related venous thromboembolism (VTE) is challenging. We examined the characteristics of this patient population and outcomes, including recurrent VTE, heavy menstrual bleeding, and pregnancy.

METHODS

We performed a single-institution retrospective cohort study of adolescents with a new diagnosis of VTE and concurrent use of estrogen- and/or progestin-containing medication (N = 89). We collected data on additional risk factors for thrombosis, management of hormone therapy, and anticoagulation. We compared outcomes between patients with prescribed contraception within the year after their VTE diagnosis (n = 52) with those without (n = 37).

RESULTS

At least one additional risk factor for thrombosis was identified in 92% of patients, and 73% had two or more. The most common additional thrombosis risk factors were obesity (35%), family history (33%), and recent immobility (33%). Ninety-seven percent of patients were receiving combined hormonal medications, and 42% of patients had their medication stopped and not replaced with an alternative. Heavy menstrual bleeding was reported while on anticoagulation in 46% of patients with a documented menstrual history. Recurrent VTE occurred in 9.0% of patients. The group without prescribed contraception had a significantly higher rate of pregnancy in the two years after VTE diagnosis (18% vs. 1.9%, p = .04). Two pregnancies occurred while on warfarin.

DISCUSSION

Early assessment of contraceptive needs and menstrual bleeding symptoms are needed after diagnosis of hormone-related VTE in adolescent females. Access to contraceptive methods associated with low thrombosis risk is important for the prevention of unplanned pregnancy in this patient population.

Pulmonary Embolism and Pregnancy-Challenges in Diagnostic and Therapeutic Decisions in High-Risk Patients

Diagnosis of acute PE in pregnant women with haemodynamic instability is following the general integrated risk-adapted diagnostic algorithm and starts with bedside echocardiography to assess RV function. If RV dysfunction is identified, a prompt and immediate reperfusion without further imaging should be initiated. Although pregnancy is listed as a relative contraindication of systemic thrombolysis, in pregnant women with acute PE and haemodynamic instability thrombolysis must be considered. In those cases, other treatment strategies as surgical embolectomy or catheter-directed low-dose thromboylysis or percutaneous thrombectomy should be taken into consideration as well. A multidisciplinary team with experience of PE management in pregnancy should be consulted to reach consensus on the best treatment approach.

Society for Maternal-Fetal Medicine Consult Series #61: Anticoagulation in pregnant patients with cardiac disease

Pregnancy in individuals with a mechanical heart valve has been classified as very high risk because of a substantially increased risk of maternal mortality or severe morbidity. Lifelong therapeutic anticoagulation is a principal component of the medical management of mechanical heart valves to prevent valve thrombosis. Anticoagulation regimens indicated outside of pregnancy for patients with mechanical valves should be continued during pregnancy with the possibility of modifications based on the type of valve, the trimester of pregnancy, individual risk tolerance, and circumstances around the time of delivery. The purpose of this document is to provide recommendations regarding the management of anticoagulation for common cardiac conditions complicating pregnancy, including mechanical heart valves, atrial fibrillation, systolic heart failure, and congenital heart disease.

Surgical techniques for aortic valve xenotransplantation

Background

Heart valve replacement in neonates and infants is one of the remaining unsolved problems in cardiac surgery because conventional valve prostheses do not grow with the children. Similarly, heart valve replacement in children and young adults with contraindications to anticoagulation remains an unsolved problem because mechanical valves are thrombogenic and bioprosthetic valves are prone to early degeneration. Therefore, there is an urgent clinical need for growing heart valve replacements that are durable without the need for anticoagulation.

Methods

A human cadaver model was used to develop surgical techniques for aortic valve xenotransplantation.

Results

Aortic valve xenotransplantation is technically feasible. Subcoronary implantation of the valve avoids the need for a root replacement.

Conclusion

Aortic valve xenotransplantation is promising because the development of GTKO.hCD46.hTBM transgenic pigs has brought xenotransplantation within clinical reach.

Diagnosis and management of arrhythmias in pregnancy

Arrhythmias are the most common cardiac complications occurring in pregnancy. Although the majority of palpitations in pregnancy may be explained by atrial or ventricular premature complexes, the full spectrum of arrhythmias can occur. In this article, we establish a systematic approach to the evaluation and management of arrhythmias in pregnancy. Haemodynamically unstable arrhythmias warrant urgent cardioversion. For mild cases of benign arrhythmia, treatment is usually not needed. Symptomatic but haemodynamically stable arrhythmic patients should first undergo a thorough evaluation to establish the type of arrhythmia and the presence or absence of structural heart disease. This will ultimately determine the necessity for treatment given the potential risks of anti-arrhythmic pharmacotherapy in pregnancy. We will discuss the main catalogue of anti-arrhythmic medications, which have some established evidence of safety in pregnancy. Based on our appraisal, we provide a treatment algorithm for the tachyarrhythmic pregnant patient.

Alternatives to Low Molecular Weight Heparin for Anticoagulation in Pregnant Women with Mechanical Heart Valves in Middle-Income Countries: A Cohort Study

Objective

To compare cardiac complications and pregnancy outcomes in women with mechanical heart valves (MHVs) on two different anticoagulation regimens in a middle-income country.

Methods

We conducted a retrospective cohort study comparing outcomes in pregnant women with MHVs that received vitamin K antagonists (VKAs) throughout pregnancy versus sequential anticoagulation (heparins in the first trimester and peripartum period and VKAs for the remainder of pregnancy), at a tertiary centre in South India, from January 2011 to August 2020.

Results

We identified 138 pregnancies in 121 women, of whom 32 received VKAs while 106 were on sequential anticoagulation. There were no differences between groups with regard to maternal deaths [0 vs. 6 (5.7%), p = 0.34], thromboembolic events [2 (6.3%) vs. 15 (14.2%), p = 0.36], haemorrhagic complications [4 (12.5%) vs. 12 (11.3%), p = 0.85], cardiac events [1 (3.1% vs. 17 (16%), p = 0.07], spontaneous miscarriages [5 (15.6%) vs. 13 (12.3%), p = 0.62], stillbirths [0 vs. 5 (5.4%), p = 0.581] or neonatal deaths [2 (8.7%) vs. 1 (1.1%), p = 0.11]. Both cases of warfarin embryopathy received >5 mg warfarin in the first trimester. Thromboembolic events were associated with subtherapeutic doses of heparin in the first and third trimesters and the early postpartum period. Fetal growth restriction and preterm birth complicated 34 (29.3%) and 26 (22.4%) pregnancies respectively.

Conclusion

Pregnancy complications associated with MHVs in middle-income countries may be reduced by multidisciplinary surveillance, avoiding first-trimester warfarin if daily doses >5 mg and ensuring therapeutic levels of heparin during bridging in the first and third trimesters and peripartum period. Administration of low-dose aspirin should be considered as this may prevent placentally-mediated complications of pregnancy.

Highlights

Pregnancy complications associated with MHVs in LMICs may be reduced by multidisciplinary surveillance, avoiding first-trimester warfarin if the daily dose is >5 mg, ensuring therapeutic levels of heparin in the first trimester and peripartum period.Placentally-mediated complications of pregnancy can be prevented by administering low-dose aspirin.Vitamin K antagonists or sequential regimen can be used as suitable alternatives to LMWH for anticoagulation in pregnant women with MHVs.

Contemporary best practice in the management of pulmonary embolism during pregnancy

Approximately 1–2 per 1000 pregnancies are complicated by venous thromboembolism (VTE). VTE includes deep vein thrombosis (DVT) and pulmonary embolism (PE) and the diagnostic management of pregnancy-related VTE is challenging. Current guidelines vary greatly in their approach to diagnosing PE in pregnancy as they base their recommendations on scarce and weak evidence. The pregnancy-adapted YEARS diagnostic algorithm is well tolerated and is the most efficient diagnostic algorithm for pregnant women with suspected PE, with 39% of women not requiring computed tomographic pulmonary angiography. Low-molecular-weight heparin is the first-choice anticoagulant treatment in pregnancy and should be continued until 6 weeks postpartum and for a minimum of 3 months. Direct oral anticoagulants should be avoided in women who want to breastfeed. Management of delivery needs a multidisciplinary approach in order to decide on an optimal delivery plan. Neuraxial analgesia can be given in most patients, provided time windows since last low-molecular-weight heparin dose are respected. Women with a history of VTE are at risk of recurrence during pregnancy and in the postpartum period. Therefore, in most women with a history of VTE, thromboprophylaxis in subsequent pregnancies is indicated.

The reviews of this paper are available via the supplemental material section.

Continued use of Warfarin in lower dose has safe maternal and neonatal outcomes in pregnant women with Prosthetic Heart Valves

Background and Objective:

There has been concerns regarding the safety of Warfarin in pregnant females due to its teratogenic potential. At the same time warfarin provides best anticoagulation in patients with prosthetic valves. Various dosage regimes have been tried to strike a balance between safety of mother and the avoidance of congenital anomalies in the newborn. This study was conducted to observe the effect of Warfarin in pregnant mothers taking different doses of warfarin, and their neonatal outcome, in our outdoor patients.

Methods:

This is a cross sectional observational study conducted at the Faisalabad Institute of Cardiology. The pregnant mothers taking warfarin for prosthetic valve replacement who presented to our specialized clinic between November 2016 to April 2017 were included in the study. These included a total of 75 females between the age of 20-35 years. To compare the dose related effect of warfarin, two groups of the patients were formed. One group comprised of patients taking warfarin ≤5mg while the other group consisted of those who were taking >5mg of warfarin daily. These patients were followed till their delivery. The information was collected about the maternal and fetal outcomes. The maternal outcomes including mode of delivery/miscarriage, peripartum bleeding and any valve related thromboembolic complications. The fetal outcomes included birth weight, maturity, embryopathy and congenital anomaly in the baby.

Results:

Patient’s mean age was 29.25±3.75 years. The mitral valve replacement was present in 60% patients (n=45) while 25.3% patients (n=19) had aortic valve replacement and 14.7% patients (n=11) had double valve replacement. In this group 30 patients (40%) had taken <5 mg warfarin and 45 patients (60%) had received >5 mg warfarin medicine. Miscarriages, cesarean sections, low birth weight and prematurity were more common in patients receiving warfarin >5 mg with p-values 0.005, 0.046, 0.01 and 0.033 respectively. No case of fetal embryopathy was found in both groups.

Conclusion:

No case of embryopathy was found in each group which signifies that warfarin in lower doses is safe anticoagulant in patients with prosthetic valve replacements.

Atrial fibrillation during pregnancy: a 9-month period with limited options

Pregnancy is a physiological condition with reversible hemodynamic, neurohormonal and coagulation changes to the maternal body during this 9‑month period. The occurrence of atrial fibrillation (AF) is altogether rare among pregnant women, but necessitates immediate treatment und further work-up. Despite numerous pharmacological and invasive therapeutic modalities for AF in non-pregnant patients, very few options are considered safe enough for the fetus and the mother during pregnancy. Commonly used medications such as beta blockers, calcium channel antagonists, antiarrhythmic drugs and anticoagulation therapy must be carefully individualized according to the week of gestation and possible underlying comorbidities of the mother, thus highlighting the importance of an interdisciplinary evaluation by a cardiologist and a gynecologist. The current review summarizes the existing knowledge and treatment options for AF in pregnancy and suggests a simplified algorithm for this clinical constellation.

Managing anticoagulation in pregnancy for the anaesthetist on the labour ward

Pregnancy is a hypercoaguable state. As part of the multidisciplinary team on labour ward, the anaesthetist plays a role particularly in advising the women and the obstetric team regarding the timing and even choice of regional analgesia given the potential risk of complications, as this may be affected by the anticoagulation treatment pregnant women may be on. It is important to understand the type of anticoagulation regimens parturients might be on and what sort of risk assessment they must undergo, as this has obstetric and anaesthetic implications. Although a rare presentation, management of women with mechanical prosthetic heart valves who are pregnant requires detailed and highly specialised care in tertiary care centres with a well-developed multidisciplinary team and pathway. Despite their rare presentation, it is important to understand the intricate and complex management that these women require as they have a high morbidity and mortality rate.

Using Supervised Learning Methods to Develop a List of Prescription Medications of Greatest Concern during Pregnancy

INTRODUCTION

Women and healthcare providers lack adequate information on medication safety during pregnancy. While resources describing fetal risk are available, information is provided in multiple locations, often with subjective assessments of available data. We developed a list of medications of greatest concern during pregnancy to help healthcare providers counsel reproductive-aged and pregnant women.

METHODS

Prescription drug labels submitted to the U.S. Food and Drug Administration with information in the Teratogen Information System (TERIS) and/or Drugs in Pregnancy and Lactation by Briggs & Freeman were included (N = 1,186 medications; 766 from three data sources, 420 from two). We used two supervised learning methods ('support vector machine' and 'sentiment analysis') to create prediction models based on narrative descriptions of fetal risk. Two models were created per data source. Our final list included medications categorized as 'high' risk in at least four of six models (if three data sources) or three of four models (if two data sources).

RESULTS

We classified 80 prescription medications as being of greatest concern during pregnancy; over half were antineoplastic agents (n = 24), angiotensin converting enzyme inhibitors (n = 10), angiotensin II receptor antagonists (n = 8), and anticonvulsants (n = 7).

DISCUSSION

This evidence-based list could be a useful tool for healthcare providers counseling reproductive-aged and pregnant women about medication use during pregnancy. However, providers and patients may find it helpful to weigh the risks and benefits of any pharmacologic treatment for both pregnant women and the fetus when managing medical conditions before and during pregnancy.

2020 ACC/AHA Guideline for the Management of Patients With Valvular Heart Disease: Executive Summary: A Report of the American College of Cardiology/American Heart Association Joint Committee on Clinical Practice Guidelines

AIM

This executive summary of the valvular heart disease guideline provides recommendations for clinicians to diagnose and manage valvular heart disease as well as supporting documentation to encourage their use.

METHODS

A comprehensive literature search was conducted from January 1, 2010, to March 1, 2020, encompassing studies, reviews, and other evidence conducted on human subjects that were published in English from PubMed, EMBASE, Cochrane, Agency for Healthcare Research and Quality Reports, and other selected database relevant to this guideline. Structure: Many recommendations from the earlier valvular heart disease guidelines have been updated with new evidence and provides newer options for diagnosis and treatment of valvular heart disease. This summary includes only the recommendations from the full guideline which focus on diagnostic work-up, the timing and choice of surgical and catheter interventions, and recommendations for medical therapy. The reader is referred to the full guideline for graphical flow charts, text, and tables with additional details about the rationale for and implementation of each recommendation, and the evidence tables detailing the data considered in developing these guidelines.

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

Valvular heart disease (VHD) is generally well tolerated during pregnancy; however, the dramatic changes in hemodynamics that occur during pregnancy can lead to clinical decompensation in high-risk women. Women with VHD considering pregnancy should undergo preconception counseling with a high-risk obstetrician and cardiologist to review the maternal, fetal, and obstetric risks of pregnancy and delivery. Vaginal delivery is recommended for most women with VHD. Given the complexity of managing VHD during pregnancy, women should be managed by a multidisciplinary Pregnancy Heart Team during pregnancy, consisting of a high-risk obstetrician, cardiologist, and cardiac anesthesiologist.

Cardiovascular Medications in Pregnancy: A Primer

Cardiovascular disease and cardiovascular disease-related disorders remain among the most common causes of maternal morbidity and mortality in the United States. Due to increased rates of obesity, delayed childbearing, and improvements in medical technology, greater numbers of women are entering pregnancy with preexisting medical comorbidities. Use of cardiovascular medications in pregnancy continues to increase, and medical management of cardiovascular conditions in pregnancy will become increasingly common. Obstetricians and cardiologists must familiarize themselves with the pharmacokinetics of the most commonly used cardiovascular medications in pregnancy and how these medications respond to the physiologic changes related to pregnancy, embryogenesis, and lactation.

Marine Antithrombotics

Thrombosis remains a prime reason of mortality worldwide. With the available antithrombotic drugs, bleeding remains the major downside of current treatments. This raises a clinical concern for all patients undergoing antithrombotic therapy. Novel antithrombotics from marine sources offer a promising therapeutic alternative to this pathology. However, for any potential new molecule to be introduced as a real alternative to existing drugs, the exhibition of comparable anticoagulant potential with minimal off-target effects must be achieved. The relevance of marine antithrombotics, particularly sulfated polysaccharides, is largely due to their unique mechanisms of action and lack of bleeding. There have been many investigations in the field and, in recent years, results have confirmed the role of potential marine molecules as alternative antithrombotics. Nonetheless, further clinical studies are required. This review covers the core of the data available so far regarding the science of marine molecules with potential medical applications to treat thrombosis. After a general discussion about the major biochemical steps involved in this pathology, we discuss the key structural and biomedical aspects of marine molecules of both low and high molecular weight endowed with antithrombotic/anticoagulant properties.

Comparison of Different Anticoagulation Regimens Regarding Maternal and Fetal Outcomes in Pregnant Patients With Mechanical Prosthetic Heart Valves (from the Multicenter ANATOLIA-PREG Registry)

Mechanical prosthetic heart valves (MPHVs) are highly thrombogenic, and a pregnancy-induced procoagulant status increases the risk of MPHV thrombosis. Despite numerous case reports, 2 major registries and meta-analyses/systematic reviews, optimal anticoagulation therapy during pregnancy remains controversial. The goal of this study was to evaluate different anticoagulation regimens in pregnant patients with MPHVs. The outcomes of anticoagulation regimens were assessed retrospectively in pregnant women (110 women; 155 pregnancies) with MPHVs. The study population was divided into 5 groups according to anticoagulation regimens used; high-dose warfarin (>5 mg/d) throughout pregnancy (group 1), low-dose warfarin (≤5 mg/d) throughout pregnancy (group 2), low molecular weight heparin (LMWH) throughout pregnancy (group 3), first trimester LMWH, 2nd and 3rd trimester warfarin (group 4), first 2 trimester LMWH, and 3rd trimester warfarin (group 5). Of 155 pregnancies, 55 (35%) resulted in fetal loss; whereas 41 (27%) cases with abortion (miscarriage and therapeutic) and 14 (9%) stillbirths occurred. The comparison of the groups showed that the whole abortion rates including therapeutic abortion were significantly higher in Group 1, and lower in groups 3 and 5 (p <0.001). However, miscarriage rates were similar between the groups. A total of 53 pregnancies (34%) suffered from prosthetic valves thrombosis (PVT) during pregnancy or in the postpartum period. Group 2 had significantly lower rates of PVT than the other groups (p <0.001). In conclusion, the current data suggests that there is no optimal therapy, and that all managements have advantages and disadvantages. Low-dose warfarin (≤5 mg/day) regimen with therapeutic international normalized ratio levels may provide effective maternal protection throughout pregnancy with acceptable fetal outcomes.

Anticoagulation in Deep Venous Thrombosis: Current Trends in the Era of Non- Vitamin K Antagonists Oral Anticoagulants

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Anticoagulation therapy is the cornerstone of treatment in acute vein thrombosis (DVT) and it aims to reduce symptoms, thrombus extension, DVT recurrences, and mortality. The treatment for DVT depends on its anatomical extent, among other factors. Anticoagulation therapy for proximal DVT is clearly recommended (at least for 3 months), while AT for isolated distal DVT should be considered, especially in the presence of high thromboembolic risk factors. The optimal anticoagulant and duration of therapy are determined by the clinical assessment, taking into account the thromboembolic and bleeding risk in each patient in a case-by-case decision making. Non-Vitamin K antagonists oral anticoagulants (NOACs) were a revolution in the anticoagulation management of DVT. Nowadays, NOACs are considered as first-line therapy in the anticoagulation therapy for DVT and are recommended as the preferred anticoagulant agents by most scientific societies. NOACs offer a simple route of administration (oral agents), a rapid onset-offset of their action along with a good efficacy and safety profile in comparison with Vitamin K Antagonists (VKAs). However, there are issues about their efficacy and safety profile in specific populations with high thromboembolic and bleeding risks, such as renal failure patients, active-cancer patients, and pregnant women, in which VKAs and heparins were the standard care of treatment. Since the available data are promising for the use of NOACs in end-stage chronic kidney disease and cancer patients, several ongoing randomized trials are currently trying to solve that issues and give evidence about the safety and efficacy of NOACs in these populations.

Cardiac arrhythmias in pregnant women: need for mother and offspring protection

Cardiac arrhythmias are the most common cardiac complication reported in pregnant women with and without structural heart disease (SHD); they are more frequent among women with SHD, such as cardiomyopathy and congenital heart disease (CHD). While older studies had indicated supraventricular tachycardia as the most common tachyarrhythmia in pregnancy, more recent data indicate an increase in the frequency of arrhythmias, with atrial fibrillation (AF) emerging as the most frequent arrhythmia in pregnancy, attributed to an increase in maternal age, cardiovascular risk factors and CHD in pregnancy. Importantly, the presence of any tachyarrhythmia during pregnancy may be associated with adverse maternal and fetal outcomes, including death. Thus, both the mother and the offspring need to be protected from such consequences. The use of antiarrhythmic drugs (AADs) depends on clinical presentation and on the presence of underlying SHD, which requires caution as it promotes pro-arrhythmia. In hemodynamically compromised women, electrical cardioversion is successful and safe to both mother and fetus. Use of beta-blockers appears quite safe; however, caution is advised when using other AADs, while no AAD should be used, if at all possible, during the first trimester when organogenesis takes place. Regarding the anticoagulation regimen in patients with AF, warfarin should be substituted with heparin during the first trimester, while direct oral anticoagulants are not indicated given the lack of data in pregnancy. Finally, for refractory arrhythmias, ablation and/or device implantation can be performed with current techniques in pregnant women, when needed, using minimal exposure to radiation. All these issues and relevant current guidelines are herein reviewed.

Pregnancy outcomes in women with mechanical prosthetic heart valves

Pregnancy outcomes in women with mechanical heart valves (MHV) remain poor. The thrombogenicity of MHV, the hypercoagulable state of pregnancy and limitations of current anticoagulation strategies combine to give a very high risk state. Recent additions to the literature in the form of registry data as well as meta-analyses and systematic reviews have highlighted the risks of thrombotic and haemorrhagic events in mothers and increased fetal complication rates. There remains a lack of consensus about the optimal anticoagulation approach to mitigate the risks to mother and fetus and registry data confirm poor quality of care. Current guidelines recommend the sequential use of heparin and vitamin K antagonists, but low molecular weight heparin is often used throughout the pregnancy, with inadequate monitoring in many instances. There is an urgent need to standardise the management of such women, which should be undertaken in specialist centres, supported by research on optimal anticoagulation regimens and the impact on pregnancy outcomes.

Vitamin K antagonist rodenticides display different teratogenic activity

Vitamin K antagonists (VKA) are not recommended during pregnancy because warfarin (a first-generation VKA) is associated with a malformation syndrome "the fetal warfarin syndrome" (FWS). VKA are also used for rodent management worldwide. Recently, the Committee for Risk Assessment responsible for the European chemical legislation for advances on the safe use of chemicals had classed 8 anticoagulant used as rodenticides in the reprotoxic category 1A or 1B. This classification emerges from a read-across prediction of toxicity considering the warfarin malformation syndrome. Herein, our study explores the teratogenicity of warfarin at the human therapeutic dose and that of bromadiolone, a second-generation anticoagulant rodenticide. Using a rat model, our study demonstrates that warfarin used at the therapeutic dose is able to induce teratogenicity, while in the same conditions bromadiolone does not induce any teratogenic effect, challenging the classification of all VKA as reprotoxic molecules.

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.

Anesthetic challenges in a pregnant patient with post mitral valve replacement, complete heart block, and coagulopathy coming for emergency cesarean section: A case report

A 24-year-old primigravida with a history of rheumatic heart disease and prosthetic mitral valve on oral anticoagulation who was lost follow-up during the third trimester presented with premature rupture of membranes. On evaluation, she had new-onset complete heart block. She was temporarily paced but developed cardiac failure. Anesthetic challenges and management of this parturient with post mitral valve replacement, complete heart block, and warfarin-induced coagulopathy for emergency cesarean delivery are discussed in this case report. Ours is the first case report of a pregnant patient with new onset of complete heart block during pregnancy several years after mitral valve replacement.

Heart disease and pregnancy: State of the art

The association between heart disease and pregnancy is increasingly prevalent. Although most women with heart disease tolerate the physiological changes of pregnancy, there are heart conditions that manifest for the first time during pregnancy and others that totally contraindicate a pregnancy. It is therefore important to establish multidisciplinary teams dedicated to the management of women with heart disease who intend to become, or who already are, pregnant. The aim of this article is to systematically review current knowledge on the approach to women with high-risk cardiovascular disease during pregnancy.

Ectopic mineralization in heart valves: new insights from in vivo and in vitro procalcific models and promising perspectives on noncalcifiable bioengineered valves

Ectopic calcification of native and bioprosthetic heart valves represents a major public health problem causing severe morbidity and mortality worldwide. Valve procalcific degeneration is known to be caused mainly by calcium salt precipitation onto membranes of suffering non-scavenged cells and dead-cell-derived products acting as major hydroxyapatite nucleators. Although etiopathogenesis of calcification in native valves is still far from being exhaustively elucidated, it is well known that bioprosthesis mineralization may be primed by glutaraldehyde-mediated toxicity for xenografts, cryopreservation-related damage for allografts and graft immune rejection for both. Instead, mechanical valves, which are free from calcification, are extremely thrombogenic, requiring chronic anticoagulation therapies for transplanted patients. Since surgical substitution of failed valves is still the leading therapeutic option, progressive improvements in tissue engineering techniques are crucial to attain readily available valve implants with good biocompatibility, proper functionality and long-term durability in order to meet the considerable clinical demand for valve substitutes. Bioengineered valves obtained from acellular non-valvular scaffolds or decellularized native valves are proving to be a compelling alternative to mechanical and bioprosthetic valve implants, as they appear to permit repopulation by the host's own cells with associated tissue remodelling, growth and repair, besides showing less propensity to calcification and adequate hemodynamic performances. In this review, insights into valve calcification onset as revealed by in vivo and in vitro procalcific models are updated as well as advances in the field of valve bioengineering.