Biological versus mechanical heart valve prosthesis during pregnancy in women with congenital heart disease

Pregnancy outcomes in women with a mitral valve prosthesis: A systematic review and meta-analysis

Objectives

To evaluate the ongoing debate concerning the choice of valve prosthesis for women requiring mitral valve replacement (MVR) and who wish to conceive. Bioprostheses are associated with risk of early structural valve deterioration. Mechanical prostheses require lifelong anticoagulation and carry maternal and fetal risks. Also, the optimal anticoagulation regimen during pregnancy after MVR remains unclear.

Methods

A systematic review and meta-analysis was conducted of studies reporting on pregnancy after MVR. Valve- and anticoagulation-related maternal and fetal risks during pregnancy and 30 days' postpartum were analyzed.

Results

Fifteen studies reporting 722 pregnancies were included. In total, 87.2% of pregnant women had a mechanical prosthesis and 12.5% a bioprosthesis. Maternal mortality risk was 1.33% (95% confidence interval [CI], 0.69-2.56), any hemorrhage risk 6.90% (95% CI, 3.70-12.88). Valve thrombosis risk was 4.71% (95% CI, 3.06-7.26) in patients with mechanical prostheses. 3.23% (95% CI, 1.34-7.75) of the patients with bioprostheses experienced early structural valve deterioration. Of these, the mortality was 40%. Pregnancy loss risk was 29.29% (95% CI, 19.74-43.47) with mechanical prostheses versus 13.50% (95% CI, 4.31-42.30) for bioprostheses. Switching to heparin during the first trimester demonstrated a bleeding risk of 7.78% (95% CI, 3.71-16.31) versus 4.08% (95% CI, 1.17-14.28) for women on oral anticoagulants throughout pregnancy and a valve thrombosis risk of 6.99% (95% CI, 2.08-23.51) versus 2.89% (95% CI, 1.40-5.94). Administration of anticoagulant dosages greater than 5 mg resulted in a risk of fetal adverse events of 74.24% (95% CI, 56.11-98.23) versus 8.85% (95% CI, 2.70-28.99) in ≤5 mg.

Conclusions

A bioprosthesis seems the best option for women of childbearing age who are interested in future pregnancy after MVR. If mechanical valve replacement is preferred, the favorable anticoagulation regimen is continuous low-dose oral anticoagulants. Shared decision-making remains priority when choosing a prosthetic valve for young women.

Anticoagulation During Pregnancy with a Mechanical Pulmonary Valve: Patient and Medical Perspective

This article discusses the challenges of supporting a successful pregnancy in a woman with multiple prosthetic heart valves and a complicated cardiac history, from both the patient and provider perspective. The patient is a 29-year-old female with truncus arteriosus type I with initial neonatal VSD closure and right ventricular to pulmonary artery conduit. At the age of 13, she subsequently required truncal and pulmonary valve replacements with mechanical prostheses. Standardizing an approach to anticoagulation in pregnancy in women with prosthetic heart valves is not always possible. Her story demonstrates the importance of an innovative approach to unique cases; by extrapolating what is known about pregnancy and prosthetic heart valves, cardiologists can provide the best outcomes. Simultaneously, non-directive counseling is essential throughout this period to engage the patient in shared decision-making when balancing risks and benefits of each approach to anticoagulation.

Mechanical Heart Valves, Pregnancy, and Bleeding: A Systematic Review and Meta-Analysis

Anticoagulant therapy is essential in pregnant women with mechanical heart valves to prevent valve thrombosis. The risk of bleeding complications in these patients has not gained much attention. This systematic review and meta-analysis investigate the prevalence of bleeding peri-partum and post-partum in women with mechanical heart valves and also investigate whether bleeding risk differed across anticoagulant regimens or according to delivery mode. The present study was conducted according to The Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) statement. Studies reporting bleeding prevalence in pregnant women with mechanical heart valves receiving anticoagulant therapy were identified through PubMed and Embase on December 08, 2021. Data on bleeding complications, delivery mode, and anticoagulation therapy were extracted. A total of 37 studies were included, reporting 423 bleeding complications in 2,508 pregnancies. A meta-analysis calculated a pooled prevalence of 0.13 (95% confidence interval [CI]: 0.09-0.18) bleeding episodes per pregnancy across anticoagulant regimens. The combination of unfractionated heparin (UFH) and vitamin K antagonist (VKA) and single VKA therapy showed the lowest risk of bleeding (8 and 12%). Unexpectedly, the highest risk of bleeding was found in women receiving a combination of low-molecular-weight-heparin (LMWH) and VKA (33%) or mono-therapy with LMWH (22%). However, this could be dose related. No difference in bleeding was found between caesarean section versus vaginal delivery (p = 0.08). In conclusion, bleeding episodes are common during pregnancy in women with mechanical heart valves receiving anticoagulant therapy. A combination of UFH and VKA or VKA monotherapy showed the lowest risk of bleeding.

Functional non-glutaraldehyde treated porcine pericardium for anti-coagulation, anti-calcification, and endothelial proliferation bioprosthetic heart valves

In the last decade, the number of transcatheter heart valve replacement for severe heart valve disease has increased exponentially. Although the bioprosthetic artificial heart valve (BHV) has similar fluid dynamics performance to the original heart valve compared with mechanical heart valve so that there is no need to take long-term anticoagulant drugs to prevent thromboembolism, transcatheter BHV replacement are still at risk for thrombosis during the first few months according to the clinical data. However, the use of antithrombotic drugs can also increase the risk of bleeding. Therefore, it is particularly important to improve the anticoagulant properties for the BHV itself. In this work, a kind of non-glutaraldehyde cross-linked BHV material with excellent antithrombotic ability has been prepared from carboxylated oxazolidine treated porcine pericardium (consisting of collagen, elastin and glycoprotein) with the further graft of the anticoagulant heparin sodium via hydrophilic modified chitosan. Along with the similar mechanical properties and collagen stability comparable to the glutaraldehyde cross-linked porcine pericardium (PP), these functional non-glutaraldehyde cross-linked PPs exhibit better biocompatibility, promoted endothelial proliferation and superior anti-calcification ability. More importantly, excellent anticoagulant activity can be observed in the hematological experiments in vivo and in vitro. In summary, these excellent performances make these functional non-glutaraldehyde cross-linked PPs great potentialities in the BHV applications.

Graphical abstract

Cardiovascular Considerations in Caring for Pregnant Patients: A Scientific Statement From the American Heart Association

Cardio-obstetrics has emerged as an important multidisciplinary field that requires a team approach to the management of cardiovascular disease during pregnancy. Cardiac conditions during pregnancy include hypertensive disorders, hypercholesterolemia, myocardial infarction, cardiomyopathies, arrhythmias, valvular disease, thromboembolic disease, aortic disease, and cerebrovascular diseases. Cardiovascular disease is the primary cause of pregnancy-related mortality in the United States. Advancing maternal age and preexisting comorbid conditions have contributed to the increased rates of maternal mortality. Preconception counseling by the multidisciplinary cardio-obstetrics team is essential for women with preexistent cardiac conditions or history of preeclampsia. Early involvement of the cardio-obstetrics team is critical to prevent maternal morbidity and mortality during the length of the pregnancy and 1 year postpartum. A general understanding of cardiovascular disease during pregnancy should be a core knowledge area for all cardiovascular and primary care clinicians. This scientific statement provides an overview of the diagnosis and management of cardiovascular disease during pregnancy.

Morbidity in Pregnant Women with a Prosthetic Heart Valve

BACKGROUND

Women with a prosthetic heart valve are perceived to be at higher risk for adverse outcomes, but their absolute and relative risk of experiencing maternal morbidity and cardiac complications is largely unknown.

OBJECTIVE

The objective of the study was to determine the risk of maternal morbidity and cardiac complications in women with a prior heart valve replacement, compared with matched counterparts without known cardiac disease.

STUDY DESIGN

A retrospective population-based matched cohort study was completed in the province of Ontario, Canada, where there is universal health care. Included were all women of child-bearing age who had bioprosthetic or mechanical replacement of the mitral or aortic valve, April 1994 to March 2016 (valve replacement group). Those in the valve replacement group, and who had at least 1 birth, were 1:4 matched to a community comparison group without heart disease and who also had at least 1 birth. Matching was by maternal age at cohort entry, year of cohort entry, geographic area, income level, and age at first birth. Maternal outcomes included severe maternal morbidity, all-cause mortality, and cardiac morbidity as well as a prolonged hospital length of stay >7 days. Relative risks and 95% confidence intervals were further adjusted for age at birth and immigration status.

RESULTS

There were 90 live births among the 64 women in the valve replacement group and 404 live births among the 253 women in the matched community comparison group. There were no stillbirths. Severe maternal morbidity occurred in 13 pregnancies (14.4%) in the valve replacement group and 6 (1.5%) in the community comparison group (adjusted relative risk, 9.73, 95% confidence interval, 3.70-25.59); there were no maternal deaths. The corresponding rates of prolonged hospital length of stay were 37.8% and 18.8% (adjusted relative risk, 2.33, 95% confidence interval, 1.48-3.67).

CONCLUSION

Pregnant women who had aortic or mitral valve replacement were more likely to experience severe maternal morbidity, as well as prolonged hospital length of stay, than matched counterparts without heart disease. This information can enhance shared decision making about the timing of valve replacement and pregnancy planning in young and middle-aged women. To determine the absolute and relative risk of maternal morbidity and cardiac complications in women with prior heart valve replacement, a retrospective population-based matched cohort study was completed in the province of Ontario, Canada, where there is universal health care. Included were all women of child-bearing age who had bioprosthetic or mechanical replacement of the mitral or aortic valve, April 1994 to March 2016 (valve replacement group). Those in the valve replacement group, and who had at least one birth, were 1:4 matched to a community comparison group without heart disease and who also had at least 1 birth. There were 90 live births among the 64 women in the valve replacement group and 404 live births among the 253 women in the matched community comparison group. Severe maternal morbidity occurred in 13 pregnancies (14.4%) in the valve replacement group and 6 (1.5%) in the community comparison group (adjusted relative risk, 9.73); there were no maternal deaths. The corresponding rates of prolonged hospital length of stay were 37.8% and 18.8% (adjusted relative risk, 2.33). In summary, pregnant women who had an aortic or mitral valve replacement were more likely to experience severe maternal morbidity, as well as prolonged hospital length of stay, than matched counterparts without heart disease.

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.

No longer rare diseases and obstetric anesthesia

PURPOSE OF REVIEW

With new medical technologies and changing life styles, maternal demographics has changes and consequently older and sicker women are becoming pregnant.In this review, we present these different high-risk parturient populations, which were once considered rare for the practicing obstetric anesthesiologist.

RECENT FINDINGS

With lifestyle and medical advances, older and sicker women are getting pregnant. Older women are more prone to pregnancy complications. Cancer survivors are becoming pregnant and more pregnant women are being diagnosed with cancer. Previous neurological and cardiac conditions considered not compatible with pregnancy are now seen more frequently. As the rate of obesity increases so does the rate of obstructive sleep apnea, which is known to be associated with many adverse maternal and neonatal sequalae. Finally, increased use of both opioids and marijuana has led to increased number of pregnant women using these illicit substances.

SUMMARY

Future research and implementation of international guidelines for management of these high-risk parturient population is necessary in order to reduce maternal and neonatal morbidity.