Mechanical heart valve prosthesis in pregnancy - multicenter retrospective observational study

Abstract

Background: Mechanical heart valves carry signifi cant risk during pregnancy. Aim: To assess the risk of pregnancy and delivery for mother and child in women with mechanical heart valve prosthesis. Methods: Multicenter retrospective observational study of women with mechanical heart valve prosthesis. The regimen with low molecular weight heparin throughout pregnancy (LMWH) was compared to warfarin since the second trimester (W). Results: Out of 419 pregnant women with cardiovascular diseases we assessed 14 women with mechanical heart valve prosthesis (3.3%) who experienced 23 pregnancies. There were 13 pregnancies with aortic valve prosthesis, 8 with prosthesis of atrio-ventricular valves and 2 pregnancies with both aortic and mitral valve prosthesis. LMWH regimen was used in 18 pregnancies, W in 5 pregnancies. Major maternal complications occurred in 65% of pregnancies, including 3 strokes and 3 urgent cardio-surgical procedures, all in women with LMWH regimen. Prosthetic valve thrombosis occurred in 26%, all in the LMWH group; no thrombosis was found in W group, (p = 0.166). Major bleeding occurred in 30% with no difference between LMWH and W groups (p = 0.596). Fetal loss represented 26% of all pregnancies with no difference between LMWH and W group (p = 1). The birth weight was not signifi cantly different between LMWH and W groups (2496 ± 327 g vs. 3132 ± 592 g, p = 0.12). Conclusion:The rate of maternal and fetal complications in pregnant women with mechanical valve prosthesis is still high. The anticoagulation regimen using warfarin since the second trimester appears to be the safest one. The best prevention of complications is to avoid the implantation of mechanical valve prosthesis in girls and women in fertile age.

Pregnancy outcomes in women with mechanical prosthetic heart valves: a prospective descriptive population based study using the United Kingdom Obstetric Surveillance System (UKOSS) data collection system

“…The data collection methodology used provides an unbiased cohort and is the only prospective, population‐based (national) study of pregnancies with MPHVs in situ. Other published cohorts relate to self‐selecting centres, particular treatment regimens, valves in a particular position, or are retrospective population studies of birth registry data …”

“…Warfarin is thought to have the lowest risk of maternal complications but is associated with higher rates of fetal complications and demise . LMWH is safe for the fetus, but doubts have been expressed about its efficacy in preventing maternal complications . European Society for Cardiology guidelines have called for more research to identify the best treatment for pregnant women .…”

Prosthetic heart valves in pregnancy, outcomes for women and their babies: a systematic review and meta‐analysis

“…27 There were seven retrospective studies, two population-based cohort studies, 20,21 two multicentre unselected case series 28,32,33 and three single-centre unselected case series 28,30,31 (Table 1). Ten studies captured a total of 305 women undertaking 392 pregnancies.…”

“…Eight of the 11 studies allowed identification of perinatal mortality 20,21,[27][28][29]31,32,34 and three studies had insufficient details to differentiate early pregnancy loss from fetal death at >22 weeks. 30,33,35 No studies reported the incidence of infective endocarditis or neonatal admissions to the intensive care unit.…”

“…21 Of the remaining studies without control groups, one study 32 was awarded the maximum six stars, seven were awarded five stars [27][28][29]31,[33][34][35] and one was awarded three stars. 30 All included studies were assessed as including an adequate representation of cases, with appropriate follow up (Table 1).…”