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Unlabelled: Graft disease remains a therapeutic challenge. Procedural complications and unsatisfactory patency rates are realized with both percutaneous intervention and repeat coronary artery bypass graft (CABG) surgery. The efficacy of sirolimus-eluting stents (SES) for the treatment of de novo coronary artery disease has been established, but the use of this technology to treat bypass graft disease remains undefined. The aim of this study was to evaluate the safety and feasibility of SES to treat patients with high-risk bypass graft disease., Methods: The compassionate use of SES (SECURE) study included patients with recurrent coronary disease and no acceptable alternative available treatment, including brachytherapy or CABG. Outcomes from 76 patients (n = 94 lesions) with graft lesions treated with SES in the U.S. were compared with the outcomes of 176 patients (n = 311 lesions) with only native vessels. IVUS follow-up was performed at 8 months in 14 patients with graft SES treatment., Results: In-hospital outcomes were similar between both groups, with 99% of patients discharged without adverse events. The incidence of target vessel failure including death, MI, and TVR at 12 months in the bypass graft group (55.3%) was similar to that observed in the native vessel group (45.5%, p = 0.17). Intimal hyperplasia (IH) measured by IVUS was 11.8 +/- 16.5%; 50% of patients with graft SES had < 1% IH at 8 months., Conclusion: Implantation of SES in high-risk patients with recurrent bypass graft disease is feasible. SES represents a future.

Both gamma and beta irradiation delivered via a radioactive catheter-based line source have been shown to have efficacy in reducing restenosis. However, these catheter-based treatments have some limitations, including the safety of handling sources ranging from 30 mCi to 500 mCi. Alternatively, one could use a stent as the platform for local radiation delivery as a means to prevent restenosis. Experimental studies have demonstrated that stents ion implanted with the b-particle emitter 32P can reduce neointima formation. Clinical evaluation of the radioisotope stent began in the fall of 1996. Dose escalation studies have now been completed in approximately 250 patients with 32P, b-particle emitting stents ranging from 0.5 microCi to 24 microCi. Overall, these feasibility trials have demonstrated a clear, dose-dependent reduction of neointimal hyperplasia within the stent structure, but with an unanticipated finding of a relatively high incidence of restenosis at the stent margins. The purpose of this paper is to review the current status of radioactive stents, with an emphasis on the key elements of stent design and stent delivery that could impact the long-term efficacy of this device.

Objectives: The purpose of this study was to compare the arterial response following implantation of a stainless-steel, balloon-expandable, tubular slotted stent with that of a novel computer-designed, multi-cellular stent in normal porcine coronary arteries., Background: Intracoronary stent placement has evolved into the primary strategy for percutaneous revascularization of symptomatic coronary arterial lesions. Presently there is intense interest in developing new stent designs to improve stent delivery and biocompatability., Methods: Computer-assisted design was utilized to develop a balloon-expandable stent with symmetric expansion properties, uniform arterial wall coverage, longitudinal flexibility and radial strength. Quantitative coronary angiography and histological assessment of the stented arteries was used to evaluate the acute and chronic vascular responses to a stainless-steel, balloon-expandable, tubular slotted stent as compared to the computer-designed BX stent in the normolipemic swine., Results: Forty stents (24 BX, 16 tubular slotted) were implanted in 19 miniature swine at a mean inflation pressure of 9 atm using identical delivery systems. Eight of the BX and none of the tubular slotted stents were post-dilated with a non-compliant balloon at 12-14 atm. The mean stent-to-artery ratio was similar for the BX (1.03 +/- 0.06) and tubular slotted (1.04 +/- 0.11; p = 0.59) designs. Protrusion or asymmetric radial flaring of a strut at the stent margin was present in 1 of 23 BX stents (4.3%) and 10 of 15 tubular slotted stents (66.7%; p < 0.0001). The mean arterial injury score was significantly less for the BX stent (0.2 +/- 0.2) as compared with the tubular slotted stents (0.4 +/- 0.4; p = 0.025). At 3 days, thrombus area was similar for the BX and tubular slotted designs (0.42 +/- 0.16 mm2 versus 0.44 +/- 0.18 mm2, respectively; p = 0.88). The mean neointimal area was significantly less for the BX at 2 months (1.09 +/- 0.25 mm2 versus 2.93 +/- 2.26 mm2 in the tubular slotted stent) and at 6 months (1.10 +/- 0.26 mm2 versus 2.07 +/- 0.65 mm2 in the tubular slotted stent; p = 0.01), resulting in approximately 50% less in-stent stenosis., Conclusions: The arterial response to a balloon-expandable stent can be favorably influenced by computer-assisted modification of design in an experimental model. Further study is warranted to determine the impact of stent design upon clinical in-stent restenosis.