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Reconstitution or recanalization of a blood vessel; may involve balloon dilation, mechanical stripping of intima, forceful injection of fibrinolytics, or placement of a stent. SYN: interventional angiography. [angio- + G. plastos, formed, shaped]

- percutaneous transluminal a. (PTA) an operation for enlarging a narrowed vascular lumen by inflating and withdrawing through the stenotic region a balloon on the tip of an angiographic catheter; may include positioning of an intravascular endoluminal stent.

- percutaneous transluminal coronary a. (PTCA) an operation for enlarging a narrowed vascular lumen by inflating and withdrawing through the stenotic region a balloon on the tip of an angiographic catheter.PTCA is a minimally invasive surgical procedure for the treatment of coronary atherosclerosis. A balloon-tipped catheter is inserted percutaneously into the arterial circulation, advanced to the aortic root, and directed with a flexible guide wire to the site of coronary stenosis. Once positioned within the narrowed arterial segment, the balloon is inflated so as to stretch the lumen, fracture the obstructing plaque, or both. Balloon a. is considered successful when there is more than a 20% increase in the caliber of the stenotic artery and restoration of at least 50% of normal patency, without acute complications. The procedure has approximately a 90% immediate success rate. It offers advantages in symptom improvement and exercise tolerance when compared to medical therapy, particularly in the short term, and is less hazardous and has a shorter recovery period than coronary artery bypass grafting (CABG). Operative mortality is about 2%. There is a 1–3% risk of nonfatal acute myocardial infarction during the procedure and a 1–3% risk that emergency CABG will be required. Hence the procedure is contraindicated unless a bypass team is immediately available. It is also contraindicated in patients without demonstrated significant vascular obstruction, as well as in those with severe multivessel disease or more than 50% stenosis of the left main coronary artery. Despite the advantages of PTCA, 30–50% of patients require repeat balloon a. or CABG for restenosis within 6 months. Insertion of a stainless steel stent at the time of balloon a. to maintain arterial patency has improved initial success and reduced the 6-month restenosis rate. High-dose verapamil has also been associated with lower restenosis rates.

an·gio·plas·ty 'an-jē-ə-.plas-tē n, pl -ties surgical repair or recanalization of a blood vessel esp BALLOON ANGIOPLASTY

repair or reconstruction of a narrowed or completely obstructed blood vessel. Traditionally, this was performed during open surgery, but in modern practice angioplasty commonly refers to percutaneous transluminal angioplasty (PTA; balloon angioplasty), in which an inflatable balloon, mounted on the tip of a flexible catheter, is placed within the lumen of the affected vessel at the site of the narrowing/blockage, under X-ray control. On inflation of the balloon the lumen is reopened. In an artery this disrupts the intima (which reduces the chances of the stenosis recurring). This procedure may be performed before introducing a vascular stent. Common sites for PTA are coronary, carotid, renal, and leg arteries. See also coronary angioplasty.