SESSION TITLE: Pulmonary Vascular Disease Cases I SESSION TYPE: Affiliate Case Report Slide PRESENTED ON: Monday, October 26, 2015 at 11:00 AM - 12:00 PM INTRODUCTION: Pulmonary arteriovenous malformations (AVMs) are a rare clinical entity, especially when found in isolation with no underlying etiology. Literature review suggest that pulmonary AVMs are symptomatic in 91% of cases, with dyspnea in 82% and cyanosis in 79% of patients. Furthermore, 70% are also associated with Osler Weber Rendu Syndrome. We report a case of severe asymptomatic hypoxia, discovered incidentally on routine pre-operative evaluation, found to have isolated multiple large pulmonary AVMs. Workup failed to show any underlying etiology. CASE PRESENTATION: The patient is a 54 year old female, with a history of COPD and severe aortic valve insufficiency, diagnosed via an echocardiogram at another facility, referred to cardiovascular surgery at our hospital. During pre-surgical evaluation, she was found to be hypoxic, with oxygen saturation in the 80%s on 2L of oxygen by nasal cannula and was admitted. Upon admission, her oxygen saturation was at 85% on a non re-breather mask. She denied any symptoms. Physical examination was unremarkable. Laboratory values showed hemoglobin of 17.3g/L and hematocrit of 48.9%. Chest X-Ray revealed a mass like density in the right lower lobe (RLL). CT scan of the thorax with contrast was negative for pulmonary embolus but 4 AVMs in RLL and 2 in right upper lobe were identified. Further questioning and workup was negative for Osler-Weber-Rendu syndrome or other underlying etiology. Resting echo showed an EF of 70% and a Bubble Echocardiogram revealed extensive right to left shunting. Bubbles entered from the pulmonary venous drainage into the left atrium consistent with AVMs. She had a pulmonary angiogram and AVMs of the RLL were embolizedx2 and an amplatzer vascular occlusion plug was deployedx2. After embolization, the patient's oxygen saturation was at 95% on 6L of oxygen. A Transesophageal Echo showed moderate aortic insufficiency and she decided to forego cardiac surgery. DISCUSSION: Studies show most cases of pulmonary AVMs have an underlying etiology and are symptomatic in 91% of patients. Our case represents a patient with large asymptomatic pulmonary AVMs with no underlying etiology. CONCLUSIONS: It shows that in patients presenting with hypoxia with no clear underlying cause, pulmonary AVMs can be considered as a cause and that pulmonary angiogram and embolization of AVMS is the cornerstone of treatment of pulmonary AVMs. Reference #1: Faughnan ME, LUI YW, Wirth JA, et al. Diffuse Pulmonary arteriovenous malformations: characteristics and prognosis. Chest 2000; 117:31 DISCLOSURE: The following authors have nothing to disclose: Asad Omar No Product/Research Disclosure Information