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

Pregnancy with a prosthetic heart valve, thrombosis, and bleeding: the ESC EORP Registry of Pregnancy and Cardiac disease III

BACKGROUND AND AIMS

Pregnancy in women with a prosthetic heart valve is considered high risk, primarily due to the need for effective anticoagulation. However, data on the relationship between anticoagulation practices and pregnancy outcomes are very limited.

METHODS

The Registry of Pregnancy and Cardiac disease is a global registry that prospectively enrolled pregnancies in women with a prosthetic heart valve between January 2018 and April 2023. Detailed data on anticoagulation, including dosage and monitoring, and cardiovascular, pregnancy, and perinatal outcomes were collected.

RESULTS

In total, 613 pregnancies were included of which 411 pregnancies were in women with a mechanical valve and 202 were in women with a biological valve. The chance of an uncomplicated pregnancy with a live birth in women with a mechanical valve was 54%, compared with 79% in women with a biological valve (P < .001). Thromboembolic and haemorrhagic complications most frequently occurred when low-molecular weight heparin (LMWH)-based regimens were used. Valve thrombosis occurred in 24 (6%) women, and a prosthetic valve in mitral position was associated with valve thrombosis (odds ratio 3.3; 95% confidence interval 1.9-8.0). A thromboembolic event occurred in 12 (10%) women with anti-Xa monitoring and in 9 (21%) women without (P = .060). Foetal death occurred in 20% of all pregnancies.

CONCLUSIONS

More favourable outcomes were found in women with a biological valve compared with a mechanical valve. In women with a mechanical valve, the use of LMWH was associated with an increased risk of thromboembolic complications. A mitral prosthetic valve was identified as a predictor for valve thrombosis. The benefit could not be confirmed nor refuted, in terms of reduced thromboembolic events, from using anti-Xa level monitoring in women on LMWH.

Anticoagulant therapy in pregnant women with mechanical and bioprosthetic heart valves

OBJECTIVE

The aim of the present study was to review maternal and fetal outcomes in pregnant women with prosthetic heart valves.

METHODS

A retrospective record review of pregnant women with prosthetic heart valves on anticoagulation was performed at the Specialist Cardiac Antenatal Clinic, Johannesburg South Africa from 2015 to 2023.

RESULTS

Fifty pregnancies with mechanical heart valves and three with tissue valves, on anticoagulation for comorbid atrial fibrillation were identified. The majority were of African ethnicity at a mean age of 33 ± 6 years. Anti-Xa adjusted enoxaparin was commenced at 10.5 ± 5.6 weeks' gestation until delivery in 48 (90.6%) pregnancies and warfarin was continued in five (9.4%) pregnancies. The live birth rates on enoxaparin and warfarin were 56.3% (95% confidence interval [CI]: 42.3-69.3) and 20.0% (95% CI: 2.0-64.0), respectively. There were 12 (22.6%) miscarriages at a mean of 11.3 ± 3.7 weeks' gestation, four (7.5%) intrauterine fetal deaths on warfarin and two (3.8%) warfarin embryopathy/fetopathy. The rates of antepartum/secondary postpartum bleeding and primary postpartum bleeding were 29.4% (95% CI: 18.6-43.1) and 5.9% (95% CI: 1.4-16.9), respectively. Maternal complications included anemia (n = 11, 20.8%), arrhythmia (n = 2, 3.8%), heart failure (n = 2, 3.8%) and paravalvular leak (n = 2, 3.8%). There was one (1.9%) mitral valve thrombosis and one (1.9%) stuck valve in pregnancies who defaulted warfarin prior to pregnancy. There were no maternal deaths.

CONCLUSION

Multidisciplinary management of pregnant women with prosthetic heart valves with anti-Xa adjusted low molecular weight heparin throughout pregnancy represents an effective anticoagulation option for low-middle-income countries.

Assessment of Genetic Variants Linked to Susceptibility to Mechanical Prosthetic Valve Thrombosis

Prosthetic valve thrombosis (PVT) is a critical and life-threatening condition driven by multifactorial etiologies, including genetic predispositions. The study was designed as a single-center retrospective manner. Echocardiographic features and genetic test including factor II/prothrombin (G20210A), factor V Leiden (G1691A), factor V R2 (A4070G), apolipoprotein (Apo) B-100 (G10708A), ApoE (C112R), ApoE (R158C), methylenetetrahydrofolate reductase (MTHFR) C677T, MTHFR A1298C, factor XIII G103T (V34L), β-fibrinogen (455G>A), PAI-1 4G/5G, and HPA-1 GPIIIa (T196C) genotyping variations were assessed. We performed genetic tests on 175 patients with PVT (biologically women [n = 124, 70.9%], with a mean age of 49.8 ± 13.1 years) and 101 patients (biologically women [n = 57, 56.4%], with a mean age of 54.7 ± 13.6 years) without thrombus formation. The thrombosis group was significantly younger compared with controls (p = 0.004). The percentage of patients with mechanical aortic valves was significantly lower in the thrombosis group compared with controls (22.3% vs 34.7%, p = 0.025). A significant difference was observed between the thrombosis and control groups regarding the genotype ratios of factor II/prothrombin (G20210A) (heterozygous, 6.8% vs 1%, p = 0.043) and HPA-1 GPIIIa (T196C) (homozygous mutant, 7.8% vs 0%, p = 0.034). In addition, there was a significant association of heterozygous MTHFR (A1298C) variation with obstructive thrombosis compared with nonobstructive thrombosis (46.9% vs 29.2%, p = 0.046). In conclusion, this is the first study to report a potential association between genetic variants, including HPA-1 GPIIIa (T196C), factor II/prothrombin (G20210A), MTHFR (A1298C), and PVT, necessitating extensive further research and additional clinical consideration.

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 < .001), obstructive MVT (16 vs 0%, P = .04), MVT requiring treatment (28 vs 0%, P = .003), and cerebral embolism (24 vs 3.4%, P = .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 = .015) and treatment for MHV thrombus (4.2 vs 28%, P = .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 = .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.

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.

Peripartum considerations for women with cardiac disease

PURPOSE OF REVIEW

The aim of this review of cardiac disease in pregnancy is to delineate current best practices and highlight emerging themes in the literature.

RECENT FINDINGS

Cardiovascular disease is the leading cause of death among pregnant women in the United States. Many clinicians and institutions have developed care pathways to approach care in these high-risk patients including highly coordinated multidisciplinary teams. The diagnosis of pulmonary hypertension is the greatest risk factor for an adverse event in pregnant women. Vaginal delivery, with good neuraxial anesthesia, is usually the preferred mode of delivery in women with cardiac disease, although the rate of cesarean delivery is higher among women with heart disease.

SUMMARY

The leading cause of morbidity and mortality in pregnant women is cardiac disease. Preconception counseling is useful for optimizing patients for pregnancy and setting appropriate expectations about care and outcomes. Ensuring that women are cared for in centers with appropriate multidisciplinary resources is key for improving outcomes for cardio-obstetric patients.