Bioresorbable scaffolds for complex coronary interventions.

Bioresorbable scaffolds (BRS) have been introduced to clinical practice to avoid some limitations associated with the presence of permanent metal prostheses in coronary arteries. Due to elimination of the natural vasomotion of the vessel and flow disturbance, stents impair endothelial function, increasing the risk of adverse events such as late and very late thrombosis or accelerated neoatherosclerosis. Additionally, the presence of metallic stents hinders non-invasive imaging of coronaries and may exclude the possibility of bypass graft anastomosis within the stented segment. The use of fully bioresorbable scaffolds would allow for an effective treatment of coronary lesions while overcoming the limitations related to the prolonged presence of metal prostheses in coronary vessels. After early positive clinical results of BRS implanted in simple lesions in small number of patients, large randomised trials revealed numerous limitations of this technology, with unacceptably high incidence of scaffold thrombosis and myocardial infarction. Nevertheless, the negative results of the studies render the learning curve of interventional cardiologists introducing into clinical practice this novel technology. Optimal stenting technique combined with extensive use of intravascular imaging may contribute to obtaining promising results also in patients with complex stenosis, like thrombotic lesions, bifurcations, chronic total occlusions, long and calcified lesions.