OBJECTIVES:The goal of this study was to compare the efficacy of elective stent implantation and balloon angioplasty for new lesions in small coronary arteries. BACKGROUND:Palmaz-Schatz stents have been designed and approved by the Food and Drug Administration for use in coronary arteries with diameters > or = 3.0 mm. The efficacy of elective stent placement in smaller vessels has not been determined. METHODS:By quantitative coronary angiography, 331 patients in the Stent Restenosis Study (STRESS) I-II were determined to have a reference vessel < 3.0 mm in diameter. Of these, 163 patients were randomly assigned to stenting (mean diameter 2.69 +/- 0.21 mm), and 168 patients were assigned to angioplasty (mean diameter 2.64 +/- 0.24 mm). The primary end point was restenosis, defined as > or = 50% diameter stenosis at 6-month follow-up angiography. Clinical event rates at 1 year were assessed. RESULTS:Baseline clinical and angiographic characteristics were similar in the two groups. Procedural success was achieved in 100% of patients assigned to stenting and in 92% of patients assigned to angioplasty (p < 0.001). Abrupt closure within 30 days occurred in 3.6% of patients in both groups. Compared with angioplasty, stenting conferred a significantly larger postprocedural lumen diameter (2.26 vs. 1.80 mm, p < 0.001) and a larger lumen at 6 months (1.54 vs. 1.27 mm, p < 0.001). Restenosis (> or = 50% diameter stenosis at follow-up) occurred in 34% of patients assigned to stenting and in 55% of patients assigned to angioplasty (p < 0.001). At 1 year, event-free survival was achieved in 78% of the stent group and in 67% of the angioplasty group (p = 0.019). CONCLUSIONS:These findings suggest that elective stent placement provides superior angiographic and clinical outcomes than balloon angioplasty in vessels slightly smaller than 3 mm.

Objectives. The goal of this study was to compare the efficacy of elective stent implantation and balloon angioplasty for new lesions in small coronary arteries.Background. Palmaz-Schatz stents have been designed and approved by the Food and Drug Administration for use in coronary arteries with diameters greater than or equal to 3.0 mm. The efficacy of elective stent placement in smaller vessels has not been determined.Methods. By quantitative coronary angiography, 331 patients in the Stent Restenosis Study (STRESS) I-II were determined to have a reference vessel <3.0 mm in diameter, Of these, 163 patients were randomly assigned to stenting (mean diameter 2.69 +/- 0.21 mm), and 168 patients were assigned to angioplasty (mean diameter 2.64 +/- 0.24 mm). The primary end point was restenosis, defined as greater than or equal to 50% diameter stenosis at 6-month follow up angiography. Clinical event rates at 1 year were assessed,Results. Baseline clinical and angiographic characteristics were similar in the two groups, Procedural success was achieved in 100% of patients assigned to stenting and in 92% of patients assigned to angioplasty (p < 0.001). Abrupt closure within 30 days occurred in 3.6% of patients in both groups. Compared with angioplasty, stenting conferred a significantly larger postprocedural lumen diameter (2.26 vs. 1.80 mm, p < 0.001) and a larger lumen at 6 months (1.54 vs, 1.27 mm, p < 0.001). Restenosis (greater than or equal to 50% diameter stenosis at follow-up) occurred in 34% of patients assigned to stenting and in 55% of patients assigned to angioplasty (p < 0.001). At 1 year, event-free survival was achieved in 78% of the stent group and in 67% of the angioplasty group (p = 0.019).Conclusions. These findings suggest that elective stent placement provides superior angiographic and clinical outcomes than balloon angioplasty in vessels slightly smaller than 3 mm. (C) 1998 by the American College of Cardiology.

Elective Palmaz-Schatz intracoronary stent implantation does not increase the risk for coronary artery aneurysm formation. Angiographic restenosis and clinical outcome are not affected by the development of a coronary artery aneurysm after percutaneous transluminal coronary artery or scent placement.

Coronary artery stent implantation is used increasingly to treat restenosis after balloon angioplasty. This study demonstrates that a short interprocedural interval, between initial angioplasty and stent implantation, is a significant risk factor for in-stent restenosis.

Peripheral vascular complications are a significant source of morbidity after coronary artery stent implantation. The goal of this study was to assess the incidence, risk factors, and management of vascular complications after stent placement. The study population consisted of 101 consecutive patients who underwent stent placement for either elective or bailout indications. All patients received a standardized anticoagulation regimen of aspirin, dipyridamole, low molecular weight dextran, heparin, and warfarin. Peripheral vascular access sites were examined daily until hospital discharge. Vascular complications occurred in 16 of 101 (16%) patients, including femoral artery pseudoaneurysm (n = 11), hematoma requiring transfusion or surgery (n = 4), and arteriovenous fistula (n = 1). Intervention was required in 14 of 16 (88%) patients with complications. These included transfusion (n = 7), ultrasound-guided compression (n = 8), and/or vascular surgery (n = 7). Length of hospital stay was prolonged in patients with complications (14 +/- 9 vs. 8 +/- 5 d, P < 0.001). The development of peripheral vascular complications did not correlate with clinical or procedural variables such as age, cardiovascular risk factors, arterial sheath size, or elective vs. bailout indication. After the introduction of a pneumatic vascular compression device (FEMOSTOP, C.A. Bard, Billerica, MA), a significant reduction in vascular complications was observed. Complications occurred in only 1 of 41 (2.4%) patients in whom the compression device was used in contrast to 13 of 58 (22.4%) patients compressed manually (P < 0.01). Thus peripheral vascular complications are frequent after coronary artery stent placement and are associated with serious morbidity and prolongation of hospital stay. These complications are significantly reduced by the use of a pneumatic vascular compression device despite intensive systemic anticoagulation.

The purpose of this interim analysis of the SAVED Restenosis Trial was to assess the acute results of balloon angioplasty (PTCA) and elective PalmazSchatz coronary stent placement in the treatment of de novo venous bypass graft lesions. As of August 1, 1994, 128 patients (60 PTCA, 68 Stent) have been enrolled at 13 centers. Baseline demographics were similar in both groups. Mean graft ages in the PTCA and Stent groups were 9.8 ± 4.2 vs 9.7 ± 4.5 years (p = ns). Initial angiographic results by core laboratory analysis and clinical events from 0 to 30 days were as follows:Angiographic resultsPICAStentClinical Events (%)PICAStentVessel diameter (mm)3.213.18Death3.35.9Baseline mid (mm)0.980.93O-wave MI1.71.5Final mid (mm)2.122.85Bypass Surgery6.70**Final % diam stenosis3312*Closure: ≥24 hrs332.9Procedure success (%)8596**>24 hrs1.70*p < 0.01**p < 0.05 vs PICA p < 0.01 p < 0.05 vs PICA One or more major clinical events occurred in 11.7% of PTCA patients vs 5.9% of Stent patients (p = ns). Crossover from assigned to alternative therapy (including bypass surgery) was 13.3% for the PTCA group vs 1.5% for the Stent group (p < 0.01). In conclusion, the preliminary findings of this prospective trial indicate: (1) Elective stent placement in de novo saphenous vein bypass graft lesions achieves a superior initial angiographic result compared to balloon angioplasty; (2) Stents confer a salutary effect on early clinical events with less frequent need for alterna1e therapies including coronary bypass surgery.

Healing of intimal dissections after balloon angioplasty (PTCA) was prospectively assessed by morphologic and quantitative coronary analysis in a restenosis trial of PTCA vs coronary stenting (STRESS). The population for this substudy consisted of 202 patients assigned to balloon PTCA of de novo native coronary lesions. Based on NHLBI criteria, dissection after PTCA was present in 72 patients (35%). Baseline lesion characteristics were similar in patients with and without dissection except for higher frequency of bends ≥ 45° in the dissection group (28 vs 12%, p < 0.01). Compared to lesions without dissection, the presence of a dissection was associated with significantly less acute gain from PTCA (0.98 ± 0.56 vs 1.26 ± 0.44 mm, p < 0.0001) and greater residual percent diameter stenosis (45 ± 20 vs 33 ± 10%, p < 0.001), Accordingly, bailout stenting to treat a failed PTCA result was used in 13/72 (18%) patients with dissection in contrast to only 1/130 (0.8%) patients without dissection (p < 0.0001). Follow-up angiography was performed at 6.6 ± 2.3 months in 83% of eligible patients. Of the 44 patients restudied by late angiography who had post-PTCA dissection (but no bailout stenting), complete resolution of the intimal flap was observed in 41 or 93.2%. Late loss was similar in lesions with and without post-PTCA dissection (0.46 ± 0.31 vs 0.43 ± 032 mm, p = ns). Angiographic restenosis ≥50% diameter stenosis) was present in 45% (20/44) of lesions with dissection and in 40% (43/107) of lesions without dissection (p = ns). In conclusion, although coronary dissection remains a critical determinant of acute PTCA failures, nonocclusive intimal tears characteristically heal with complete resolution within 6 months. Furthermore, the presence of an intimal dissection does not influence the restenosis rate.