Guidance
2 The condition and procedure
The condition
2.1 Transcatheter aortic valve implantation (TAVI) aims to provide a less invasive alternative to open cardiac surgery for treating aortic stenosis, avoiding the need for sternotomy and cardiopulmonary bypass. However, debris may be dislodged during the TAVI procedure. This can enter the cerebral circulation and embolise, causing cerebral ischaemic events including a stroke.
The procedure
2.2 Percutaneous insertion of a cerebral protection device aims to prevent debris dislodged during TAVI from passing into the cerebral circulation. The aim is to reduce the risk of cerebral ischaemic events including a stroke.
2.3 During the TAVI procedure, before the valve is inserted, a cerebral protection device is inserted percutaneously through the radial or femoral artery. Depending on the type of device used, it is placed into the aortic arch or into the brachiocephalic (innominate) and left common carotid arteries. It is deployed to protect the ostia of the brachiocephalic (innominate) artery and the left common carotid artery. It may also protect the left subclavian artery, depending on the type of device used. It works either by filtering dislodged debris from the blood, or by deflecting dislodged debris away from the cerebral circulation to the systemic circulation. The device is removed at the end of the TAVI procedure.
2.4 The evidence review identified 3 types of cerebral protection devices. One is a deflector system that covers all 3 main branches of the aortic arch. The 2 other types cover the brachiocephalic trunk and the left common carotid artery; 1 is a filter system, the other is a deflector system.