PULMONARY ARTERIOVENOUS MALFORMATION: A MYRIAD OF PRESENTATIONS

Abstract

SESSION TITLE: Medical Student/Resident Pulmonary Vascular Disease 2 SESSION TYPE: Med Student/Res Case Rep Postr PRESENTED ON: 10/09/2018 01:15 PM - 02:15 PM INTRODUCTION: Pulmonary arteriovenous malformations (PAVM) are abnormal direct communications between the pulmonary arteries and veins without interposition of a capillary bed. Heart failure in Hereditary hemorrhagic telangiectasia (HHT) due to hepatic AVM is a known entity. Heart failure due to PAVM is not well elucidated CASE PRESENTATION: A 78-year-old female with known history of HHT presented with orthopnea and pedal edema. Clinical examination was consistent with heart failure with raised jugular venous pressure and crackles on lung bases. She was started on lasix and digoxin. Echocardiogram and coronary angiogram on her initial presentation did not show any wall motion abnormalities or obstructive coronary disease. Over the following 3 years, her clinical course was complicated by gradually worsening cardiac function (table 1), atrial fibrillation, dual chamber pacemaker insertion, recurrent hypoxic episodes requiring supplemental home oxygen and 12 hospitalizations for above mentioned reasons. Bubble study during one of the recent hospitalizations showed appearance of bubbles in the left heart after 7 cardiac cycles suggesting an extra cardiac shunt. A CT angiogram of chest showed a 6.6 cm PAVM shunting blood from left pulmonary artery to left pulmonary vein (image 1 white arrow). Cardiac catheterization showed increased right heart pressures, with a mean pulmonary capillary wedge pressure of 27 mm hg and a step up in oxygen saturation of left pulmonary artery to 81% from 55% in right ventricle confirming shunting. Her PAVM was deemed to be the cause of her recurrent heart failure. Interventional radiology was consulted and pulmonary artery angiogram was performed with embolization of AVM by placing an amplatzer vascular plug (image 2). Post embolization her EF improved to 45%. Thereafter, she didn’t have any more hospitalizations for heart failure and is currently off Lasix. DISCUSSION: Congenital PAVMs are strongly associated with HHT. Up to one third of the patients with HHT can have PAVMs. The main pathophysiologic disturbance is shunting of blood from the pulmonary artery to veins resulting in delivery of desaturated oxygen to heart. Long standing hypoxia can cause pulmonary hypertension and preferential shunting of blood through PAVM, imposing an unusual volume load on the left ventricle which could initially result in high cardiac output. In the long run, this can cause dilated cardiomyopathy causing reduced ejection fraction and recurrent heat failure. Timely closure of symptomatic PAVMs with embolic agents,vascular plugs, coiling, surgical ligation or lobectomy could reduce or prevent the disease progression to recurrent or refractory heart failure, paradoxical embolisms. CONCLUSIONS: PAVM could be considered in the differential diagnosis when treating a patient with recurrent unexplained heart failure and hypoxia Reference #1: Pulmonary arteriovenous malformations presenting as refractory heart failure Reference #2: Diagnosis and treatment of pulmonary arteriovenous malformations in hereditary hemorrhagic telangiectasia: An overview DISCLOSURES: No relevant relationships by Abdullah Abdullah, source=Web Response No relevant relationships by Manuel Matos, source=Web Response No relevant relationships by Pratyusha Tirumanisetty, source=Web Response