The purpose of this study is to compare the use of the Micro Vascular Plug (MVP) system and other embolic devices in treatment of PAVMs. Pulmonary Arteriovenous Malformations (PAVMs) are abnormal connections between the pulmonary vein and the pulmonary artery. This affects blood flow between the heart and lungs which puts patients at risk of stroke, brain abscess, hypoxia and even sudden death. The standard treatment of PAVMs is embolization. Embolization is the placing of an embolic (synthetic agent) into a blood vessel to block blood flow. The embolic is inserted via a catheter into the blood vessel. Detachable coils are the most commonly used embolic in the treatment of PAVMs. Despite long procedure times, numerous coils that are often required to occlude a single PAVM and recanalization rates ranging from 5% to 15%, the most widely used embolic device is still the detachable coil.

Transcatheter embolization has become the standard of care in the treatment of Pulmonary Arteriovenous Malformations (PAVMs). PAVM embolization is performed to prevent right to left shunting which puts patients at risk of stroke, brain abscess, hypoxia and even sudden death. Despite long procedure times, numerous coils that are often required to occlude a single PAVM and recanalization rates ranging from 5% to 15%, the most widely used embolic device is still the detachable coil delivered through a microcatheter. An alternative to coil embolization is the Amplatzer Vascular plug (AVP). AVPs allow for quick delivery of a single occluding device. AVPs, however, cannot be delivered through a microcatheter, limiting the AVPs' utility to larger PAVM with larger feeding arteries. The new MVPTM Micro Vascular Plug System (MVP, Medtronic) was designed to combine the best of both devices and allows for the occlusion of small vessels in a quick and predictable manner with a single embolic device through a micro catheter. At the investigators' institution the investigators have a very large PAVM practice, as the investigators are a large Hereditary Hemorrhagic Telangiectasia (HHT) center of excellence. Currently there is a paucity of data comparing these devices for the treatment of PAVMs. Specifically, there is little data to inform interventional radiologists' decision making process about which device to choose based on the patient's clinical characteristics, the size of the PAVM feeding artery, and cost.

The investigators will create a registry/database of all patients who undergo embolization for Pulmonary AVM at the investigators' HHT center of excellence collecting data and adding in data from the investigators' existing PAVM database dating back at least the last 7 years. Patients with MVP embolizations will be assessed and compared to patients who are embolized with other solid embolic devices (coils/plugs). The investigators will assess reperfusion rates, immediate technical success, procedural attributes including procedure time, fluoroscopy time, contrast administration, and finally embolic and overall procedural costs.

Inclusion Criteria:

• Undergoing embolization of Pulmonary Arteriovenous Malformation (PAVM)

Exclusion Criteria:

• PAVM unable to be embolized

Patients with Pulmonary Arteriovenous Malformation (PAVM) being treated through the Interventional Radiology clinic.