Intracoronary Stenting Without Anticoagulation Accomplished With Intravascular Ultrasound Guidance

Abstract

Background The placement of stents in coronary arteries has been shown to reduce restenosis in comparison to balloon angioplasty. However, clinical use of intracoronary stents is impeded by the risk of subacute stent thrombosis and complications associated with the anticoagulant regimen. To reduce these complications, the hypothesis that systemic anticoagulation is not necessary when adequate stent expansion is achieved was prospectively evaluated on a consecutive series of patients who received intracoronary stents. Methods and Results From March 1993 to January 1994, 359 patients underwent Palmaz-Schatz coronary stent insertion. After an initial successful angiographic result with <20% stenosis by visual estimation had been achieved, intravascular ultrasound imaging was performed. Further balloon dilatation of the stent was guided by observation of the intravascular ultrasound images. All patients with adequate stent expansion confirmed by ultrasound were treated only with antiplatelet therapy (either ticlopidine for 1 month with short-term aspirin for 5 days or only aspirin) after the procedure. Clinical success (procedure success without early postprocedural events) at 2 months was achieved in 338 patients (94%). With an inflation pressure of 14.9±3.0 atm and a balloon-to-vessel ratio of 1.17±0.19, optimal stent expansion was achieved in 321 of the 334 patients (96%) who underwent intravascular ultrasound evaluation, with these patients receiving only antiplatelet therapy after the procedure. Despite the absence of anticoagulation, there were only two acute stent thromboses (0.6%) and one subacute stent thrombosis (0.3%) at 2-month clinical follow-up. Follow-up angiography at 3 to 6 months documented two additional occlusions (0.6%) at the stent site. At 6-month clinical follow-up, angiographically documented stent occlusion had occurred in 5 patients (1.6%). At 6-month clinical follow-up, there was a 5.7% incidence of myocardial infarction, a 6.4% rate of coronary bypass surgery, and a 1.9% incidence of death. Emergency intervention (emergency angioplasty or bailout stent) for a stent thrombosis event was performed in 3 patients (0.8%). The overall event rate was relatively high because of intraprocedural complications that occurred in 16 patients (4.5%). Intraprocedural complications, however, decreased to 1% when angiographically appropriately sized balloons were used for final stent dilations. There was one ischemic vascular complication that occurred at the time of the procedure and one ischemic vascular complication that occurred at the time of angiographic follow-up. By 6 months, repeat angioplasty for symptomatic restenosis was performed in 47 patients (13.1%). Conclusions The Palmaz-Schatz stent can be safely inserted in coronary arteries without subsequent anticoagulation provided that stent expansion is adequate and there are no other flow-limiting lesions present. The use of high-pressure final balloon dilatations and confirmation of adequate stent expansion by intravascular ultrasound provide ass...

Safety and efficacy of coronary stent implantation. Acute and six month outcomes of 1,126 consecutive patients treated in 1996 and 1997

“…The need for urgent surgical revascularization is becoming rare after percutaneous procedures that employ the stent technique. The incidence of new Q wave MI was lower than 1% and, it is in accordance with the results from the major randomized trials recently published [7][8][9][10] .…”

“…The comparison demonstrates that, stents can create significancy higher coronary lumen diameters, reduce the restenosis rate at the end of the first 6 months and as a consequence the need for further revascularization procedures, percutaneous or surgical, compared with the standard balloon PTCA method [4][5][6][7] . In 1995, Colombo et al 8 demonstrated that intravascular ultrasound could optimize stent delivery and implantation, applying higher balloon pressures (>12 ATM), promoting better stent symmetry, with a nearly full apposition of the stent struts in the vessel wall. These benefits of stent geometry led the author to recommend the complete cessation of the old antithrombotic pharmacological regimen, introducing a new one, aimed at a more intensive antiplatelet blockage, with the combination of aspirin and ticlopidine.…”

“…These benefits of stent geometry led the author to recommend the complete cessation of the old antithrombotic pharmacological regimen, introducing a new one, aimed at a more intensive antiplatelet blockage, with the combination of aspirin and ticlopidine. This new technique was called "optimal stent implantation" [8][9] .…”

Secondary prevention of heart disease amongst patients with lipid abnormalities: practice and trends in the United States

“…Angioplasty techniques are rapidly evolving, particularly in terms of stent technology. With effective deployment, stents do not require intensive anticoagulation and concomitantly prolonged hospital stays [47].…”

Effect of percutaneous adenovirus-mediated Gax gene delivery to the arterial wall in double-injured atheromatous stented rabbit iliac arteries

“…Coronary stents constitute, indeed, one of the most significant advances in vascular interventional therapy. A recent reduction in the initially high rate of periprocedural complications 51,52 and the demonstration of their efficacy in decreasing restenosis 4,5 has led to a marked increase in the use of stenting in clinical practice. However the restenosis rate, although less, is still in the 15-25% range.…”