Serruys, Patrick W.

Background With the thrombogenic tendency and permanent implant nature of metallic stents, synthetic polymers have been proposed as candidate materials for stents and local drug delivery designs. We investigated the biocompatibility of several synthetic polymers after experimental placement in the coronary artery. Methods and Results Five different biodegradable polymers (polyglycolic acid/polylactic acid [PGLA], polycaprolactone [PCL], polyhydroxybutyrate valerate [PHBV], polyorthoester [POE], and polyethyleneoxide/polybutylene terephthalate [PEO/PBTP]) and three nonbiodegradable polymers (polyurethane [PUR], silicone [SIL], and polyethylene terephthalate [PETP]) were tested as strips deployed longitudinally across 90° of the circumferential surface of coil wire stents. Appropriately sized polymer-loaded stents were implanted in porcine coronary arteries of 2.5- to 3.0-mm diameter. Four weeks after implantation, stent patency was assessed by angiography followed by microscopic examination of the coronary arteries. The biodegradable PCL, PHBV, and POE and the nonbiodegradable PUR and SIL evoked extensive inflammatory responses and fibrocellular proliferation (thickness of tissue response: 0.79±0.22, 1.12±0.01, 2.36±0.60, 1.24±0.36, and 1.43±0.15 mm, respectively). Less but still severe responses were observed for the biodegradable PGLA and PEO/PBTP (0.46±0.18 and 0.61±0.23 mm, respectively) and for the nonbiodegradable PETP (0.46±0.11 mm). Conclusions An array of both biodegradable and nonbiodegradable polymers has been demonstrated to induce a marked inflammatory reaction within the coronary artery with subsequent neointimal thickening, which was not expected on the basis of in vitro tests. The observed tissue response may be attributable to a combination of parent polymer compound, biodegradation products, and possibly implant geometry.

Background— The prospective, multinational, randomized Synergy Between Percutaneous Coronary Intervention With TAXUS and Cardiac Surgery (SYNTAX) trial was designed to assess the optimal revascularization strategy between percutaneous coronary intervention (PCI) and coronary artery bypass grafting (CABG), for patients with left main (LM) and/or 3-vessel coronary disease. Methods and Results— This observational hypothesis-generating analysis reports the results of a prespecified powered subgroup of 705 randomized patients who had LM disease among the 1800 patients with de novo 3-vessel disease and/or LM disease randomized to PCI with paclitaxel-eluting stents or CABG in the SYNTAX trial. Major adverse cardiac and cerebrovascular event rates at 1 year in LM patients were similar for CABG and PCI (13.7% versus 15.8%; Δ2.1% [95% confidence interval −3.2% to 7.4%]; P =0.44). At 1 year, stroke was significantly higher in the CABG arm (2.7% versus 0.3%; Δ−2.4% [95% confidence interval −4.2% to −0.1%]; P =0.009]), whereas repeat revascularization was significantly higher in the PCI arm (6.5% versus 11.8%; Δ5.3% [95% confidence interval 1.0% to 9.6%]; P =0.02); there was no observed difference between groups for other end points. When patients were scored for anatomic complexity, those with higher baseline SYNTAX scores had significantly worse outcomes with PCI than did patients with low or intermediate SYNTAX scores; outcomes for patients with CABG did not correlate with baseline SYNTAX score, but baseline EuroSCORE significantly predicted outcomes for both treatments. Conclusions— Patients with LM disease who had revascularization with PCI had safety and efficacy outcomes comparable to CABG at 1 year; longer follow-up is required to determine whether these 2 revascularization strategies offer comparable medium-term outcomes in this group of complex patients. Clinical Trial Registration— http://www.clinicaltrials.gov. Unique identifier: NCT00114972.