Abstract Number: PB2551
Meeting: ISTH 2020 Congress
Background: Management of pregnant women with mechanical heart valves (MHVs) is complicated, as they are at risk for thrombosis, bleeding and cardiac complications.
Aims: We sought to determine the various risks that occur in these women.
Methods: We performed a retrospective analysis of all women managed at a tertiary Canadian centre who had a MHVs and received LMWH throughout pregnancy.
Results: We identified 42 pregnancies (28 women), all of which had a single MHV; 96% had a bileafet or tilting-disc valve, and 71% were in the mitral position. Although 13 (46%) had prior cardiac events, all were in New York Heart Association functional class I/II at conception. LMWH was commenced at diagnosis of pregnancy. Of the available peak anti-Xa levels, based on published recommendations, 46% were in therapeutic or supra-therapeutic range, while 54% were sub-therapeutic. Three pregnancies sustained thromboembolic complications [peri-partum valvular thrombus; transient ischaemic attacks in the first trimester, prompting change to warfarin; and a cortical infarct at 24 weeks followed by a cardiac arrest, maternal death and perimortem caesarean delivery at 26 weeks’ gestation]. In the case of maternal mortality, peak anti-Xa levels were in the therapeutic range. In addition to the thromboembolic complications, there were 7 cases of major haemorrhage, three cases of heart failure, three cases of endocarditis, and two arrhythmias. All cases except the perimortem caesarean section and another with bacteremia, received regional analgesia/anaesthesia for delivery. The 42 pregnancies resulted in nine miscarriages, three pregnancy terminations, one stillbirth and 28 live births, one of which resulted in a neonatal death. There were no congenital anomalies.
Conclusions: Despite multidisciplinary care, women with MHVs receiving LMWH during pregnancy remain at risk of adverse outcomes and are a high-risk cohort. While focus on thromboembolic complications and anti-Xa monitoring is important, women are also at risk for serious bleeding and cardiovascular complications.
To cite this abstract in AMA style:
D'Souza R, Syeda A, Zaffar N, Bapoo S, Shishkina A, Sermer M, Shehata N, Silversides CK. Outcomes in Women with Mechanical Heart Valves Anticoagulated with Low Molecular Weight Heparin During Pregnancy [abstract]. Res Pract Thromb Haemost. 2020; 4 (Suppl 1). https://abstracts.isth.org/abstract/outcomes-in-women-with-mechanical-heart-valves-anticoagulated-with-low-molecular-weight-heparin-during-pregnancy/. Accessed September 27, 2023.« Back to ISTH 2020 Congress
ISTH Congress Abstracts - https://abstracts.isth.org/abstract/outcomes-in-women-with-mechanical-heart-valves-anticoagulated-with-low-molecular-weight-heparin-during-pregnancy/