Cardiac diseases in pregnancy leading to maternal mortality

Introduction

About 287000 maternal deaths occur each year worldwide.1 Cardiac disease is one of the important causes of maternal mortality and morbidity both in antepartum and postpartum period.2, 3 The overall incidence of heart disease in pregnancy is < 1%.4

The circulatory changes of pregnancy in the presence of maternal heart disease may result in adverse consequences, even death of mother or fetus.2, 5, 6 The major alteration in pregnancy include a 30-50% increase in both cardiac output and blood volume, in addition to decreased blood pressure. In cardiac pregnant patient, these modifications may lead to clinical decompensation, exposing these women to potentially life threatening situation.

Cardiac disease in pregnancy is divided into congenital and acquired. The acquired group includes RHD, cardiomyopathy and ischemic heart disease. Of these, in developing countries rheumatic heart disease is the commonest type, whereas cardiomyopathy and congenital heart disease one more common in developed countries.3

Materials and Methods

This is a 3 years retrospective study in a tertiary care hospital from 1^st January 2015 to 31^st December 2017. Total 1895 autopsies were performed by pathology department, out of which 158 were maternal mortality autopsies. Of which 17 deaths were due to cardiac diseases in pregnancy. That means 10.76% maternal mortality occurred of which 8.33% maternal mortality due to cardiac diseases in pregnancy (Table 1).

The gross specimen of heart and formalin fixed paraffin embedded sections were stained with haematoxylin and eosin were reviewed for histopathological examination. Special stains [GMS, AFB, PAS] were studied wherever required.

Results

Gross & microscopic findings

On gross examination of heart, it was moderate to markedly enlarged due to ventricular dilation in 12(70.58%) cases with marked hypertrophy of left ventricular wall in 6(35.29%) of cases.

On microscopic examination, myocardial muscle fibre hypertrophy with disarray of myofibers seen in 8(47.05%) cases, valvulitis in 1 (5.88%) case, myocarditis in 5(29.41%) and subendocardial fibrosis in 4 (23.52%) cases.

Figure 1

Gross findings of heart in rheumatic heart disease: a: Showing enlarge heart, globular in shape & apex at centre. Epicardium shows pericarditis with fibrinous grayish white exudate & congestion on heart. b: Showing mitral valve stenosis with narrowing of opening (fish mouth) and shortening & thickening of chordae tendinae. c: Showing left ventricular hypertrophy with papillary muscle hypertrophy & shortening of chordae tendinae. d: On cut open, showing slightly dilated left ventricle & mitral valve is replaced by artificial valve which is 3 cm circular, plastic with stainless steel border

Figure 2

Microscopic findings of heart in rheumatic heart disease; a: Showing fibrous thickening of epicardium with mixed inflammatory infiltrate & increased epicardial fat. b: Showing chronic healed valvulitis. c: Showing hypertrophy of myofibers with box shaped nuclei

Figure 3

Gross findings of heart in dilated cardiomyopathy; a: Showing markedly enlarged heart due to 4 chamber dilatation with focal areas of congestion; b: Showing moderately enlarged heart with left ventricular dilatation

Figure 4

Microscopic findings of heart in dilated cardiomyopathy a: Showing disarray of myofibers; b: Showing disarray of myofibers with hypertrophy of myofibers & lymphoplasmacytic infiltrate in interstitium

Figure 5

Gross findings of heart in ventricular failure and myocarditis; a: Showing markedly enlarged heart due to left ventricular dilatation; b: Showing grayish white fibrotic thickening of right & left ventricle involving interventricular septum with areas of congestion & hypertrophy of papillary muscle

Figure 6

Microscopic findings of heart in myocarditis; a: Myocardium showing destruction of myofibers with diffuse mixed inflammatory infiltrate (lymphocytes, plasma cells, histiocytes) & many multinucleated giant cells with areas of fibrosis; b: Showing special stain-GMS negative for fungi; c: Shows lymphocytic myocarditis; d: Showing hypertrophy of myofibers with fibrosis

Discussion

In the present study, out of 17 cases of maternal mortality autopsies due to cardiac diseases in pregnancy, 35.29% cases (6 cases) were of rheumatic heart disease followed by 29.40% cases (5 cases) of cardiomyopathy, which is comparable with Pujitha KS et al.7 & WS Avilla et al.8 studies but showing higher percentage of RHD & lower percentage of cardiomyopathy in Pujitha KS et al.7 study and lower percentage of RHD & cardiomyopathy in WS Avilla et al.8 study.

In our study, most common age group involved was 21-30 years in 58.8% cases (10 cases) which is in concordance with Pujitha KS et al.7 study but it is showing, 21-25 years is the commonest age group in 50% cases. The commonest presenting complaints in this study were breathlessness in 100% cases, fever with chills in 52.94% cases followed by dyspnoea on exertion and oedema which is similar to Pujitha KS et al.7 study.

In the present study, most of the cases of maternal mortality autopsies due to cardiac diseases in pregnancy were seen in multigravida in 76.47% cases, which is in disconcordance with Pujitha KS et al.7 study.

In our study, 82.35% (14 cases) cases of maternal mortality autopsies due to cardiac diseases in pregnancy delivered normal vaginally, which is in concordance with Pujitha KS et al.7 study.

In this study, congestive cardiac failure seen in 47.05% cases, pulmonary oedema and anaemia seen in 11.76% cases, which are in disconcordance with Pujitha KS et al.7 study, showing lower percentage of CCF, pulmonary oedema and higher percentage of anaemia (Table 8).

Conclusion

Pregnancy in women with heart disease is associated with high morbidity and mortality rates. So appropriate antenatal counselling, care and adequate clinical follow up during pregnancy is needed for proper outcome of pregnant female with cardiac disease.

Source of Funding

None.

Conflict of Interest

None.