Comparison of the heparin coated vs. the uncoated Jostent®—no influence on restenosis or clinical outcome

Interventional Cardiology

Comparison of the Heparin Coated vs. the Uncoated Jostent姞—No Influence on Restenosis or Clinical Outcome

Abstracts

Wo¨hrle J, Al-Khayer E, Gro¨tzinger U, et al. European Heart J 2001;22:1808 –16.

Sustained Suppression of Neointimal Proliferation by Sirolimus-Eluting Stents

Study Question: To determine whether heparin-coated stents result in better clinical and angiographic outcomes after 6 months when compared with uncoated stents. Methods: A total of 277 patients were randomized to receive a heparin-coated Jostent威 stent (156 lesions) or an uncoated Jostent威 stent (150 lesions). Indication for stent implantation included threatened vessel closure, severe dissection, suboptimal balloon result, angioplasty of a venous bypass graft and recanalization of a chronic total occlusion. All patients were pretreated with 500 mg acetyl salicylic acid orally or intravenously. Heparin administration during the procedure was adjusted to an activated clotting time ⬎280 seconds. After stent implantation, all patients received acetyl salicylic acid 100 mg daily and tyclopidine 250 mg twice daily for 4 weeks. Quantitative coronary angiography was performed on images obtained before and immediately after angioplasty and at 6 months follow-up angiography. The primary end point was binary restenosis defined as ⱖ50% diameter stenosis at 6 months follow-up. Secondary end points included angiographic documentation of subacute stent thrombosis and major cardiac events defined as death, myocardial infarction and target vessel revascularization. Results: Number of implanted stents per procedure, the length of the stented segment, implantation pressure, number of inflations and balloon to artery ratio were similar among the two groups. Lesion length and reference diameter were also similar. The minimal lumen diameter immediately after the procedure was 2.49⫾0.53mm in the uncoated group and 2.45⫾0.47mm in the coated group. Subacute stent thrombosis occurred in five lesions (1.6%). Two occurred in the uncoated stent group (1.3%) and three occurred in the coated stent group (1.9%). Six-month follow-up angiographic data were available for 243/306 lesions. The minimal lumen diameter at follow-up was 1.76⫾0.89 mm in the uncoated group and 1.69⫾0.88 mm in the coated group. The restenosis rates were 30.3% and 33.1%, respectively. Risk factors for restenosis included type B2/C lesion (p⬍0.02), stented segment longer than 16 mm (p⬍0.006) and a stent inflation pressure ⬍14 bar (p⬍0.0063). There were no significant differences in clinical event rates at follow-up. Conclusion: When compared with implantation of uncoated stents, implantation of heparin-coated stents does not result in a reduction of acute in-hospital complications, stent thrombosis or restenosis. Perspective: Heparin-coated stents have been available on the market for several years, but there have been no randomized studies that have compared them directly with

Sousa JE, Costa MA, Abizaid AC, et al. Circulation 2001;104: 2007–11. Study Question: Implantation of sirolimus-coated coronary stents has been shown to result in minimal neointimal proliferation at 4-month angiographic and intravascular ultrasound follow-up. The objective of this study was to determine whether these results are sustained over a period of 1 year. Study Design: A single sirolimus-coated Bx velocity stent was implanted in 45 patients with de novo coronary artery lesions. Of 30 patients treated in Brazil, 15 patients received a fast-release (FR) formulation (⬍15/day drug release, group 1) and 15 received a slow-release (SR) formulation (ⱖ28/day drug release, group 2). The 15 patients treated in The Netherlands received SR formulation (group 3). Quantitative coronary angiography (QCA) and IVUS imaging were performed at 4 and 12 months for group 1 and 2 and at 6 months for group 3. QCA and IVUS analysis were performed on the stented segment (18 mm, in-stent analysis) and in the stent plus 5 mm proximal and distal to the edge of the stent or the nearest side bench (in-lesion analysis). Results: Overall, there was one death on day 2 secondary to a cerebral hemorrhage in a patient who had received abciximab. Two other patients developed vessel occlusion secondary to edge dissection and were successfully treated with additional stenting. At 1-year follow-up, in-stent percent diameter stenosis was 8.9⫾6.1% in group 1, 6.7⫾7% in group 2, and in group 3 percent diameter stenosis was 8.9⫾7.6% at 6-month follow-up. In group 1, a very small decrease in minimal lumen diameter was observed between 4 and 12 months. Only two patients had ⬎10% stenosis at follow-up, no patient approached ⱖ50% diameter stenosis at 1 year by angiography or IVUS assessment and no edge restenosis was observed. Neointimal hyperplasia as measured by IVUS was 2⫾5% in group 1, 2⫾3% in group 2 and 2⫾5% in group 3. Conclusion: Implantation of sirolimus-eluting Bx velocity stents results in sustained suppression of neointimal proliferation. Perspective: The results with sirolimus-eluting stents continue to be exciting. Importantly, the data presented in this report are virtually identical to the data from the same group of patients who presented at 4-month follow-up and confirm a virtual elimination of neointimal proliferation and absence of late-stent thrombosis. MM

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uncoated stents. The results of this study suggest no benefit of provisional stenting with heparin-coated Jostent威 stents when compared with an uncoated stent in patients receiving aspirin and a thienopyridine. Whether this lack of efficacy is due to the extremely low heparin activity present on these stents (⬍1 unit of heparin per stent according to the authors) remains to be determined. MM

28.8% in the stent group and 32.8% in the angioplasty group (p⫽ns), while TVR was required in 17.8% and 20.3% of patients, respectively (p⫽0.54). There were no differences in major cardiac events including death, MI, non–Q-wave MI and coronary artery bypass surgery. Conclusion: When compared with PTCA, stenting of small vessels results in similar restenosis rates and acute longterm outcomes. Perspective: The results of this study support prior studies that have shown that in small vessels, a strategy of elective stenting results in similar acute and long-term outcomes when compared to a strategy of PTCA with provisional stenting. The authors conclude that due to a trend toward a lower in-house complication rate, a strategy of elective stenting may be a superior strategy in this patient population. This lower complication rate in the stent group was primarily driven by a lower incidence of non–Q-wave MI. MM

Stent Placement to Prevent Restenosis After Angioplasty in Small Coronary Arteries Doucet S, Schalij MJ, Vrolix MCM, et al. Circulation 2001;104: 2029 –33. Study Question: Data on stenting of small coronary arteries have been conflicting. The objective of this study was to compare stenting of small vessels with PTCA. Methods: Patients with stable angina, stabilized unstable angina or documented silent ischemia with a de novo lesion and with a reference vessel diameter between 2.3 mm and 2.9 mm were randomized to stent implantation (169 patients) or PTCA (182 patients). The angiographic target was ⬍30% residual stenosis. Crossover to stent implantation was allowed for abrupt closure, threatened closure, TIMI flow ⬍3 or ⱖ50% residual stenosis. The coronary stents used were 15-mm pre-mounted stents available in 2.5-mm and 3-mm diameters. The primary end point was angiographic restenosis defined as ⱖ50% diameter stenosis at 6-month follow-up. Secondary end points included angiographic success (⬍50% residual stenosis by QCA), procedure success defined as ⬍50% diameter stenosis by visual assessment, clinical success defined as angiographic success in the absence of death, myocardial infarction (MI), bypass surgery and target vessel vascularization (TVR) within the same hospitalization, TVR at 6 months, absolute minimal luminal diameter post procedure and at follow-up and Canadian Cardiovascular Society functional class, medication and repeat revascularization at 1 year. Results: In the stent group, four patients (2.4%) crossed over to angioplasty because of inability to cross the lesion with the stent. In the angioplasty group, 37 patients (20.3%) crossed over to stent implantation as a bailout procedure. Angiographic success was achieved in 98.2% of stent patients vs. 93.9% of PTCA patients (p⫽0.0065). Clinical success was greater in the stent group (95.3% vs. 87.9%, p⫽0.0066). There were no differences in major in-hospital cardiac complications including death (0% vs. 0%), Q-wave MI (0% vs. 0%), non–Q-wave MI (4.9% in the PTCA group vs. 1.8% in the stent group, p⫽0.142), coronary artery bypass surgery (0.5% vs. 0.6% ns) and repeat angioplasty (2.7% vs. 0.6%, p⫽0.21%). There was a trend toward a lower incidence of any event in the stent group compared to the angioplasty group (3.0% vs. 7.1%, p⫽0.07). Post-procedure residual stenosis was significantly lower after stenting (12.4⫾9.0% vs. 25.6⫾15.1%, p⫽0.001). At 6-month follow-up, the restenosis rate was

Prevention of Distal Embolization During Coronary Angioplasty in Saphenous Vein Grafts and Native Vessels Using Porous Filter Protection Eberhard G, Gerckens U, Yeung AC, et al. Circulation 2001;104: 2436 – 41. Study Question: Distal embolization and “no reflow” are known complications of percutaneous coronary and saphenous vein graft (SVG) interventions. The objective of this study was to evaluate the safety and effectiveness of a novel distal embolic protection system during SVG and native coronary interventions. Methods: The study sample included 26 consecutive patients undergoing SVG interventions (11 lesions) and native coronary interventions (15 lesions). Percutaneous revascularization was performed using the AngioGuard Emboli Capture Guidewire (ECW). The filter contains a thin porous, polimeric membrane at the distal end that permits normal distal blood flow while capturing emboli. End points included TIMI flow at baseline, before PTCA with the ECW deployed, after PTCA with the ECW deployed and at the end of the procedure. Periprocedural myocardial infarction (MI) was defined as total CK at least more than twice normal with positive CK-MB. In the first 20 patients, the distal end of the ECW was collected for morphometric analysis and immunohistochemical staining. Results: The procedural success rate was 96.2%. In one patient, the ECW could not be advanced across a distal right coronary artery lesion. There were no major adverse events and no periprocedural MI. Average TIMI flow in native coronary arteries was 1.93 at baseline, 2.43 before PTCA with the filter deployed, 2.57 after PTCA with the filter deployed and 2.67 at the end of the procedure. In the SVG group, average TIMI flow was 1.91 at baseline, 2.36 before PTCA with the filter deployed, 1.82 after PTCA with the filter deployed and 2.73 at the end of the procedure. Parti-

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