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To describe a novel approach to drug-eluting stent (DES) implantation, the sandwich technique, comprised of the simultaneous implantation of two completely overlapping DES in the same target lesion.DES effectively prevent restenosis in selected coronary lesions. However, adverse lesion characteristics may detrimentally affect outcomes after DES implantation by means of plaque prolapse, recoil or excessive neointimal hyperplasia.From July 2002 to November 2004, the sandwich technique was performed in 10 patients with very high-risk lesions. Two DES of identical size and length were implanted, one inside the other, with almost complete overlap. High-pressure postdilatation (up to 28 atm) was carried out in 6 cases. The endpoints of this preliminary evaluation were: technical feasibility, early (30-day) safety, restenosis rate and freedom from adverse events at 9-month follow up.Procedural and angiographic success was achieved in all cases. At follow-up, there were no deaths, myocardial infarctions or stent thromboses. All patients underwent angiographic follow-up; target lesion revascularization was carried out in 3 patients (30%). Of note, in no case was there evidence of aneurysmal remodeling.This study suggests that implanting 2 DES, one inside the other in a sandwich fashion, is feasible and apparently safe. This approach could be considered in situations such as plaque prolapse or stent recoil where additional scaffolding may be needed.

OBJECTIVES Reports ranged from mixed to marginal tubing wear and spallation effects as a complication of roller pumps in cardiopulmonary bypass (CPB). Because the rollers constantly compress part of the tubing, we sought to determine whether circuit materials behave differently under a 3-h simulation of CPB. METHODS Two different tubing materials (silicone and Tygon) were tested with a customized experimental circuit, designed to allow in vitro simulation of CPB with priming volumes, pressures, revolutions per minute and temperatures equivalent to the clinical scenario. Samples were analysed with optical and field-emission scanning electron microscopy. We collected 200-ml fluid samples at 4 different times: before starting the CPB (T0), when the predicted revolutions per minute corresponded to about 2 min of CPB (T1), at 90 min (T2) and at 180 min (T3). At the end of CPB, we harvested 2 samples of tubing. Lastly, optical investigations and field-emission scanning electron microscopy observations were used for qualitative and quantitative analysis of circulating fragments. RESULTS T2 and T3 fluid samples showed more particles than T1 samples. Significant differences in terms of particle numbers were detected: silicone tubing released more fragments per millilitre than Tygon tubing, with both materials releasing particles from 5 to 500 µm. Silicone tubing was associated with a time-dependent increase in small particles released (P = 0.04), whereas this did not apply to large particles or to Tygon tubing. Yet, bootstrap estimates suggested that silicone tubing was associated with the release of more small particles whereas Tygon tubing released more large particles (both P CONCLUSIONS Silicone showed a worse spallation performance than Tygon, thus appearing less safe for more complex surgery of prolonged duration or for patients with a prior cerebral ischaemic event. Additional risk and cost-effectiveness comparisons to determine the potential benefits of one type of tubing material over the other are warranted to further expand our findings.