Title : A Case of Sporadic Pulmonary AVM
Abstract:
Pulmonary arteriovenous malformations (PAVM’s) are structurally abnormal vascular communications between pulmonary arteries and veins that range in size and complexity and contribute to an anatomic right-to-left shunt. They can present with varied symptoms including dyspnea, hemoptysis and rarely cryptogenic strokes and TIA. Paradoxical embolization is the likely pathophysiology for cerebrovascular accidents associated with PAVM, and the risk increases with age, number, and size of feeding pulmonary arteries. Contrast echocardiography is the preferred initial test in suspected right to left shunts and forms part of the evaluation of cryptogenic strokes/TIA. It is possible to differentiate intracardiac and intrapulmonary shunts based on the number of cardiac cycles it takes for microbubbles to appear in the left ventricle, although CT of the chest is advisable in case of indeterminate bubble studies and in high-grade shunts. Further, treatment of symptomatic PAVM’s is indicated with embolotherapy, regardless of the feeding artery diameter. In asymptomatic cases, a feeding artery diameter >3mm is an indication for embolization, considering the increased risk of complications. Serial contrast-enhanced computed tomography is used for follow-up to look for recanalization or the development of new feeding vessels. We highlight a case of a 66 year old female who presented with TIA and was subsequently found to have an isolated PAVM which was managed with embolotherapy and followed up for recanalization with contrast imaging.
