Angiography Versus (vs) IVUS Optimisation

Inclusion Criteria: * A complex lesion is regarded as a lesion where the operator would expect a lower immediate and long term success rate compared to non-complex lesions (according to the results of Randomized Controlled Trials and from large Registries). The operator must consider the implantation of a drug-eluting stent, feasible and appropriate for this particular complex lesion Exclusion Criteria: * Contra-indication to dual anti-platelet therapy. * Ejection fraction \<30%. * Renal failure (creatinine \>2 mg/dL). * Significant co-morbidity precluding clinical follow-up. * Acute myocardial infarction in the 48 hours prior to the procedure. * In-stent restenosis * Prior brachytherapy * Thrombocytopenia \<100,000 * Unprotected left main stem stenosis * Venous or arterial grafts * Recipient of heart transplant * A positive pregnancy test in women with child bearing potential * Acute infections * Major surgery planned which will lead to discontinuation of antiplatelet therapy * Patients with prior BMS or DES implanted in the target vessel less than one year prior to the enrollment, including one year from any intercurrent restenotic or thrombotic event * Age under 18 years old. * There is no maximum number of lesions which can be treated