[Chronic total coronary occlusions: an overview]

Abstract

Chronic total coronary occlusion is defined as a > 3-month-old obstruction of a coronary artery with no anterograde filling of the distal vessel. Histologically it consists of various degrees of fibro-atheromatous plaque and thrombus depending on the mechanism of occlusion and its duration. It is identified in approximately one third of diagnostic catheterizations, but it accounts for only 10% of all percutaneous coronary interventions, as many coronary occlusions are left untreated or referred for coronary bypass surgery. Percutaneous recanalization of a coronary occlusion presents great challenges including immediate low success rates, high costs and high restenosis rates. An interventional approach is justified when ischemia or residual myocardial viability are demonstrated in the area supplied by an occluded vessel with favorable angiographic characteristics for stenting. A successful revascularization is associated with an improved long-term survival, less symptoms, a better left ventricular function and reduced need for coronary bypass surgery. The inability to cross the lesion with an angioplasty wire is the main reason for procedural failure. Stent implantation reduces the restenosis rate as compared to only balloon angioplasty, and drug-eluting stents probably further improve long-term results.