Current Status of Restenosis After Percutaneous Transluminal Coronary Angioplasty PTCA and Coronary Artery Bypass Grafting CABG – April 8, 2002

Current Status of Restenosis After Percutaneous Transluminal Coronary Angioplasty (PTCA) and Coronary Artery Bypass Grafting (CABG) – April 8, 2002

Restenosis rate within one year after PTCA reaches 35%–50%; restenosis rate within one year after CABG is 10%, and within two years it is 20%; for main coronary artery bypass grafting, the restenosis rate at five years is 15%.

Mechanisms of restenosis: ① compensatory proliferation of vascular smooth muscle cells; ② intraoperative damage to the vascular endothelium leading to platelet aggregation and involvement of the coagulation mechanism, thereby promoting thrombus formation; ③ vascular remodeling.

Prevention and treatment of restenosis: ① minimize vascular injury during surgery; ② conduct genetic research to prevent stenosis formation, essentially by introducing genes that inhibit vascular layer hyperplasia into the recipient—this falls under the category of genetic engineering; ③ intravascular irradiation: β- and γ-ray irradiation, which belongs to the field of nuclear medicine; ④ photodynamic irradiation using laser or ultraviolet light, which falls under physics; ⑤ drug-coated stents prior to surgery. In addition to these five methods, if stenosis occurs, another interventional procedure can be performed.

Such surgeries typically include: ① thrombectomy and correction of stenotic anastomoses; ② artificial vessel bypass; ③ venous arterialization: a method where a patent artery is anastomosed to the popliteal vein; ④ gene therapy: also known as autologous bypass or vascular regeneration therapy, which involves introducing genes into the proximal end of the obstructed vessel to promote regeneration of the distal segment; ⑤ thrombolysis.