MATERNAL MORTALITY DUE TO DENGUE FEVER COMPLICATING TETRALOGY OF FALLOT - A RARE CASE REPORT

Problem Statement:
Pregnancies complicated by congenital heart defects deserve special multidisciplinary care. Tetralogy of Fallot is a common cyanotic heart disease and when untreated, may progress in severity during adulthood and particularly, pregnancy. An additional comorbidity, e.g. dengue fever, makes for a precarious situation with limited treatment options. There is a high likelihood of maternal death. We report such a case.

Methods:
Case report

Results:
A 20 year-old gravida 1 of 35-36 weeks gestation presented with an unabated fever for the past 5 days. No spontaneous bleeding episodes were noted. She was not in labor with active foetal movements. She had Tetralogy of Fallot, diagnosed at age 5 with no routine medication nor follow-up. Throughout pregnancy, her antenatal care was midwife-led only. Her vital signs were stable at presentation, bar her oxygen saturation topping at 94%. Her fetus was appropriate for gestational age from ultrasound.

Her echocardiography revealed a subarterial doubly committed ventricular septal defect, 55% ejection fraction and low probability of pulmonary hypertension. Platelet level was at 22,000/mcL, having decreased from 127,000/mcL over 5 days. LDH was 403 U/L, ALT/AST 67/150 U/L. IgM dengue was non-reactive whilst IgG dengue was reactive. She was diagnosed with 35-36 weeks of gestation with modified WHO class III congenital heart disease, Tetralogy of Fallot, and dengue hemorrhagic fever.

She was given a platelet concentrate transfusion to increase her platelets to >50,000/mcL in preparation for pregnancy termination. However, she developed severely worsening dyspnea during transfusion and there were signs of foetal distress. She underwent emergency caesarean section and a repeat echocardiography afterwards. A severe supravalvular pulmonary stenosis was discovered. There was cardiomegaly and pulmonary oedema on chest x-ray. During intensive observation, her heart continue to fail with progressive decline of blood pressure despite maximum cardiac support. She eventually passed away approximately 36 hours post-surgery from cardiogenic shock and complications of transfusion-related acute lung injury.

Conclusion:
Despite optimum multidisciplinary care, pregnancy complicated with congenital heart defects further burdened by a tropical infection, such as dengue hemorrhagic fever is extremely difficult to manage well, even at a tertiary facility. Timely diagnosis, early referral and holistic management should be optimised.