Chronic total occlusion percutaneous coronary intervention failure: Learning from failure.

Experienced operators can achieve high success rates in chronic total occlusion percutaneous coronary intervention. Complications remain an important cause of chronic total occlusion intervention failure. Every effort should be made to prevent them and treat them appropriately should they occur. The most common failure mechanism for antegrade cases is failure to cross the occlusion with a guidewire. For retrograde cases the causes of failure are inability to cross the collateral (one third), inability to perform reverse CART (one third), and inability to cross with a microcatheter after guidewire crossing (one third).