What are the basic steps in performing an angioplasty procedure?
A thorough diagnostic arteriogram is performed first. This is important so that the lesion can be sized and an appropriate angioplasty balloon can be selected. The patient is then given heparin. It is important to give heparin before crossing the lesion to prevent thrombosis. The next step involves crossing the lesion with a catheter and guidewire. The lesion is then dilated with an angioplasty balloon. After the balloon is removed, an arteriogram is performed with the wire across the lesion to evaluate the result of the angioplasty. It is important to leave the wire in place until the follow-up arteriogram is performed in case a complication, such as a flow-limiting dissection or arterial rupture, occurs.
What is meant by the terms inflow and outflow ?
At least two criteria must be met for an artery to remain patent. There must be sufficient flow of blood into the vessel. With respect to the femoral artery, inflow vessels include the aorta, common iliac artery, and external iliac artery. A stenosis of any of these vessels constitutes an inflow lesion. Even with perfect inflow, there also must be flow out of a vessel for it to remain patent. With respect to the femoral artery, the popliteal, peroneal, anterior tibial, and posterior tibial arteries constitute outflow vessels.