Percutaneous coronary intervention, a historical perspective looking to the future
Although coronary artery disease (CAD) mortality rates have declined, CAD remains the leading cause of death worldwide, contributing to over 7.2 million deaths annually (1). Percutaneous coronary intervention (PCI) has made significant progress in the management of obstructive CAD over the past three decades. Since the introduction of percutaneous balloon angioplasty by Gruntzig in 1977, PCI techniques have evolved dramatically. In 1986, Puel and Sigwart deployed the first coronary stent to act as a scaffold, thus preventing vessel closure during PCI, and reducing the incidence of restenosis, which was occurring in up to 40% of cases (2). Bare metal stents (BMS), however, were still associated with intra-stent restenosis rates of 20-30% requiring re-intervention (3). Such restenosis occurred as a result of neointimal hyperplasia within the stent, caused by the migration and proliferation of vascular smooth muscle cells. In 2002, drug-eluting stents (DES), which inhibit the development of neointimal hyperplasia by releasing anti-proliferative and anti-inflammatory drugs directly into the vessel wall, were introduced as a strategy to minimize restenosis and hence the necessity for re-intervention.