THE CONUNDRUM OF TREATING SUB-MASSIVE PULMONARY EMBOLISM IN A PREGNANT PATIENT

Abstract

TOPIC: Pulmonary Vascular Disease TYPE: Medical Student/Resident Case Reports INTRODUCTION: Pulmonary embolism (PE) is an important cause of morbidity and mortality during pregnancy. 20% of maternal deaths during pregnancy are related to PE. Treatment decisions are further complicated by pregnancy, in which the outcome of the fetus is also at stake. While emerging data support the use of thrombolytic therapy during pregnancy for life-threatening PE, there are no conclusive data on the appropriate treatment (1). CASE PRESENTATION: A 7-week pregnant, 31-year-old women with history of protein C deficiency was admitted for acute onset dyspnea and syncopal episode. On physical examination, the heart rate was 136 bpm and blood pressure was 121/87 mm Hg. Oxygen saturation was 97% on room air. There was no heart murmur, lungs were clear to auscultation, and the extremities appeared normal. Troponin I level was 0.908 ng/mL and Bnp was 115pg/ml. Electrocardiogram showed sinus tachycardia. Computed tomography pulmonary angiography showed large pulmonary emboli involving the distal main pulmonary artery, left and right pulmonary arteries extending into the proximal lobar and segmental arteries bilaterally (Image 1 and 2). Echocardiogram showed a dilated right ventricle with free wall hypokinesia and displacement of the interventricular septum towards the left ventricle. Multi-disciplinary team meeting was done to discuss the risks and benefits of systemic thrombolysis and catheter-directed thrombolysis. The patient chose catheter-directed thrombolysis and after the procedure, patient's symptoms improved significantly. Due to risk of fetal anomalies from radiation exposure, patient decided to terminate her pregnancy. DISCUSSION: The guidelines on management of life-threatening acute PE in pregnancy is not well established. Teratogenicity due to thrombolytic agent has not been reported, though the risk of maternal hemorrhage is high. Catheter directed thrombolysis reduces the complications encountered in systemic thrombolysis yet require radiation exposure. CTPA and catheter directed thrombolysis usually exposes patient between 50-100mGy of radiation. During the 5th-10th week of gestation, exposures between 50-100Gy have uncertain potential side effects to the fetus. Systemic review of case series and case reports among 172 pregnant females treated with thrombolytic agents, the maternal mortality was 1%, the incidence of fetal loss was 6%, and the incidence of maternal hemorrhagic complications was 8% (2). Limited data is available for catheter directed thrombolytic therapy during 1st trimester of pregnancy, and if deemed necessary, a shared decision making with patient regarding termination of pregnancy should be made (3). CONCLUSIONS: The use of systemic or catheter directed thrombolysis is associated with positive outcomes and relatively low risk of complications. Yet, clinical judgements should be made based on individual patients risks versus benefits. REFERENCE #1: Heavner MS, Zhang M, Bast CE, Parker L, Eyler RF. Thrombolysis for Massive Pulmonary Embolism in Pregnancy. Pharmacotherapy. 2017 Nov;37(11):1449-1457. doi: 10.1002/phar.2025. Epub 2017 Oct 10. REFERENCE #2: Turrentine MA, Braems G, Ramirez MM. Use of thrombolytics for the treatment of thromboembolic disease during pregnancy. Obstet Gynecol Surv. 1995;50(7):534. REFERENCE #3: Bloom AI, Farkas A, Kalish Y. Pharmacomechanical catheter directed thrombolysis for pregnancy related iliofemoral deep vein thrombosis. J Vasc Interv Radiol 2015;26:992-1000. 10.1016/j.jvir.2015.03.001 DISCLOSURES: No relevant relationships by Ki Lee, source=Web Response No relevant relationships by Pratik Patel, source=Web Response No relevant relationships by SHREY SHAH, source=Web Response