Embolic Protection in Saphenous Vein Grafts in Coronary Arteries

Embolic protection devices are designed to capture and remove debris that may be dislodged when undergoing a Percutaneous Coronary Intervention (PCI) and to prevent debris from flowing downstream and blocking smaller arteries. There are currently two types of embolic protection systems, filters and occlusion balloons. A filter-based device allows continuous blood flow to the artery while filtering and capturing significant debris. Balloon occlusion systems temporarily stop flow by occluding the artery and then the debris is removed through an aspiration catheter.

PATIENTS

Overview

PRODUCTS FOR THIS PROCEDURE

Patients

Coronary Artery Disease (CAD) can be treated by medical therapy, angioplasty (catheter based intervention), or coronary artery bypass surgery (CABG). Bypass grafting commonly involves using the saphenous vein taken from the patient’s leg, to re-route blood flow around blockages in the coronary artery and restore blood flow to the distal vasculature. CABG surgery has high success rates, however bypass grafts are fragile and can degenerate over time.

The current treatment options for saphenous vein (bypass) graft (SVG) disease are similar to the treatment options for coronary artery disease. If you have had coronary artery bypass surgery and the graft has become diseased, your physician may perform a Percutaneous Coronary Intervention (PCI).

While balloon angioplasty and stenting are both minimally invasive and can provide a useful and effective treatment option, when they are performed in saphenous vein bypass grafts they can be at higher-risk of dislodging debris which can flow downstream and block smaller arteries. This is partially due to the characteristics of the plaque that can develop in these grafts, which can be very sensitive. One of the risks of PCI in a vein graft is the risk of “embolism.” In other words, it is possible that debris from the plaque or blood clot in your vein graft could become dislodged during the procedure and could enter your blood stream, eventually clogging the graft or one of the coronary arteries downstream. When used properly as part of the PCI procedure, embolic protection devices can help minimize that risk and protect you from potentially dangerous complications, such as a heart attack.

How the Technology Operates

Embolic protection devices are intended to capture and remove debris dislodged by PCI preventing the debris from floating downstream and blocking arteries. One type of embolic protection device is filter-based. A filter-based device is designed to allow blood in the vein graft to continue flowing while the filter captures the debris. Continual flow can be more comfortable for the patient and allow the physician better visualization of the treatment area. The FilterWire EZ™ Embolic Protection System is one such filter-based embolic protection device.

During the Procedure

The FilterWire EZ Embolic Protection System filter looks similar to a butterfly net, and is fixed on a wire. At the beginning of the procedure the filter is constrained inside a delivery sheath, and then the physician will guide it into the vein graft and past the area of blockage to be treated. Once in place, the constraint is then released and the filter pops open into position. The physician can then perform PCI with balloons, stents and other devices over the FilterWire protection wire. If any plaque or blood clots are dislodged during this time, they may be caught in the filter. The filter is intended to prevent the debris or "emboli" from traveling downstream, reducing the chance of an event such as a heart attack. To complete the procedure, the filter containing debris is captured in a retrieval sheath and removed from the patient’s body.

The specifics of your procedure and products used will be determined by the primary procedure which you are undergoing. Ask your doctor for more information about the specific procedure which you will undergo. He or she will tell you how to prepare for it, what to expect, and what your recovery will be like.