Percutaneous Coronary Intervention

Since the introduction of percutaneous balloon angioplasty by Gruentzig in 1979, percutaneous coronary intervention (PCI) has become the main treatment modality for the management of coronary heart disease. More than 1,000,000 PCI procedures are performed annually worldwide. With the advent of new therapeutic technologies, the indications for PCI have markedly expanded. Nowadays, improvements in balloon technology, popular use of coronary stent, and the proper administration of antiplatelet agents including GPIIbIIIa inhibitors have influenced the acute procedural outcomes. This technological and procedural advance in PCI has resulted in angiographic success rates of 96 to 99%, with Q-wave MI rates of 1 to 3%, emergency coronary bypass surgery rates of 0.2 to 3%, and unadjusted in-hospital mortality rates of 0.5~1.4%. However, despite the marked improvements in the acute outcome of PCI, long-term results including the restenosis rate are less impressive. The restenosis rate following balloon angioplasty reaches 30~40%, and is higher in certain clinical and angiographic subsets. The recent introduction of intracoronary stent and brachytherapy (intracoronary lesional ionizing radiation therapy) has a favorable impact on the restenosis precess including elastic recoil and intimal hyperplasia. Intracoronary stents decreased elastic recoil and remodeling and intracoronary radiation reduced intimal hyperplasia. Several randomized clinical trials to assess the efficacy of stents and intracoronary brachytherapy are ongoing with impressive results. In 2001, a breakthrough has been made in the prevention and the treatment of restenosis with the advent of a drug-eluting stent. Balloon-expandable stents coated with rapamycin or paclitaxol showed nearly 0% restenosis rate at 6-month follow-up. We might expect to solve restenosis completely in a very near future.