Efficacy of coronary stenting versus balloon angioplasty in small coronary arteries. Stent Restenosis Study (STRESS) Investigators.

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.

Frequency and outcome of development of coronary artery aneurysm after intracoronary stent placement and angioplasty. STRESS Trial Investigators.

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 stent placement.

Interprocedural interval as a predictor of stent restenosis after previous coronary angioplasty. The Palmaz-Schatz Stent Investigators.

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.

Long-term angiographic and clinical outcome after implantation of balloon-expandable stents in aortocoronary saphenous vein grafts.

Balloon angioplasty of aortocoronary saphenous vein graft lesions is associated with high restenosis and clinical event rates. The goal of this multicenter study was to assess long-term angiographic and clinical outcome of patients electively treated with single Palmaz-Schatz stents in aortocoronary saphenous vein grafts. In 198 patients (209 lesions), elective placement of single Palmaz-Schatz stents was attempted. Angiography was performed at baseline, immediately after stent placement, and at 6-month follow-up. Stent placement was successful in 98.5% of patients. One patient (0.5%) had stent thrombosis. Restenosis occurred in 34% (45 of 133) of the restudied lesions. Restenosis was lower in de novo lesions than in restenotic lesions (22% vs 51%, p < 0.001). Ostial lesions had a higher restenosis rate than nonostial lesions (61% vs 28%, p = 0.003). Freedom from death, myocardial infarction, coronary artery bypass surgery, and repeat angioplasty was present in 70% of patients. Eighty-two percent of patients with de novo lesions remained event-free at 1 year, whereas only 55% of patients with prior angioplasty were event-free at 1 year (p < 0.001). The use of the Palmaz-Schatz stent for the treatment of focal, de novo, aortocoronary saphenous vein graft lesions is associated with a high procedural success rate, a low angiographic restenosis rate, and low clinical event rates, including the need for repeat revascularization. The results of this study need validation by a prospective randomized trial comparing stent implantation with angioplasty.

Peripheral vascular complications after intracoronary stent placement: prevention by use of a pneumatic vascular compression device.

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.