FROST 4: Study of the Optimal Spreading of a Coronary Stent Guided With Pressure Into the Coronary Arteries

It is a randomized study, intending to treat, comparing the optimisation of the opening out of a stent into a coronar artery either guided with angiographic images only or with the assistance of pressure measurements plus angiographic control. Several French centers participate to demonstrate superiority of one strategy. The criterion of principal judgement is the whole of cardiac events, criterion made up with the cardiac death, myocardial infarction, revascularisation by coronary bridging and/or angioplasty and positivity of the effort test. Secondary criterions are : * comparing cost to efficacy of the two strategies * evaluating the angiographic restenosis into an under group of 200 patients (100 patients into each group) * determining the optimal threshold of measurement of intra coronary pressure in a multicentric population * comparing the ability of the different stents used to optimised the intra coronary pressure measurements