[Why perform PCI of coronary chronic occlusion and how?].

Angioplasty of coronary chronic total occlusion (CTO), defined by complete occlusion of coronary vessel with TIMI 0 flow greater than 3 months, has been avoided for many years, single vessel diseases being medically treated and multivessel diseases sent to surgeons mainly because a low success and high restenosis rates. Major improvements in devices and techniques mainly coming from Japan created a new concern about when and how to perform PCI of CTO. Clearly CTO are stable lesions but during the last years it was demonstrated that while comparing success and failure of recanalization, success improved symptoms, ischemia, left ventricular function, and even survival. Reopening CTOs can also decrease the risk of death and cardiogenic shock associated with a future acute coronary event. Selection of cases for PCI is based on well-known predictors of failure (calcifications, tortuosities, length of occluded segment and age of occlusion), on operator's experience and on a proof of viability and ischemia of the myocardium depending from occluded vessel (MRI). Many specific devices (powerful wires, microcatheters and coaxial balloons, specific guiding catheters, Tornus) and techniques (anterogrades and retrogrades through trans-septal collateral vessels) have been developed to increase success rate (70 to 90% in high volume operator hands). Outside of coronary perforations which are no more frequent in CTO lesions, some specific problems are important limitations: X-Ray exposure, contrast medium volume, and cost. With the success rate these complications are good reasons to have these procedures (or the most complex) performed by specialists.