Experience with the AVE Micro stent in native coronary arteries

Clinical outcome after successful coronary angioplasty: impact of intracoronary stent implantation

The clinical outcome after successful conventional coronary balloon angioplasty is compared with that of stent implantation after 30 days and 12 months. The study took place at the Divisions of Cardiology and Thoracic Radiology, Norrland University Hospital, Umeå, a referral centre for northern Sweden. The first 100 consecutive patients with stable or unstable angina undergoing successful percutaneous transluminal coronary angioplasty (PTCA) in 1994 and the first 100 consecutive patients undergoing successful coronary stent implantation in 1995 were included. The cardiac endpoints studied were death, myocardial infarction, need for repeat PTCA or coronary artery bypass grafting (CABG). Significantly more adverse cardiac events were observed in the PTCA group compared with the stent group. Event-free 12 months' follow-up (no deaths, myocardial infarction or re-intervention) was 64% in the PTCA group and 86% in the stent group (p < 0.005). The main explanation for the observed difference was a reduction in the need for a repeat PTCA (7 vs 18, p < 0.05) or CABG (4 vs 12, p < 0.05) in the stent group. Patients with stable or unstable angina who can be treated with a stent have a better clinical outcome than those treated with coronary balloon angioplasty only.

Long-term outcome of patients with very long stents for treatment of diffuse coronary disease

OBJECTIVES

The study sought to determine the 6-month clinical outcome of patients who underwent implantation of very long coronary stents to treat diffuse disease and/or long dissections and to compare the findings with those reported in the literature for patients who underwent implantation of multiple short coronary stents.

BACKGROUND

New designs of flexible stents enable the implantation of long stents rather than multiple short, older design stents. The initial experience is very promising but the long-term outcome has not been described yet.

METHODS

Fifty-seven consecutive patients in whom 67 long stents (>/=30 mm) were successfully deployed were included in this study. Six-month clinical and angiographic follow-up was prospectively collected. Patients with recurrent angina underwent coronary angiography without further testing. Patients who remained asymptomatic at the 6-month follow-up visit underwent positron emission tomographic imaging, and those with results suggestive of ischemia underwent coronary angiography. A combined study end point was defined as death, myocardial infarction, and the need for target vessel revascularization.

RESULTS

Only 1 patient (2%) reached a study end point at hospital discharge. An additional 20 patients (total 21 patients [37%]) reached an end point by 6 months. The outcome was not influenced by the clinical presentation (stable or unstable angina) or by the indication for stenting (elective or emergency). Predictors for adverse outcome were multiple stents per narrowing (63% vs 29%, P <. 04), and stents smaller than 3.5 mm (49% vs 22%). Narrowing and stent length were not predictive of a study end point in narrowings that were successfully treated by a single long stent.

CONCLUSIONS

Elective stenting provides an effective solution for patients with diffuse coronary disease provided that a single long stent (usually <40 mm) can cover the full length of the narrowing. The results are better when vessels larger than 3 mm are treated. Compared with multiple short stents, implantation of a single long stent is probably at least as effective, and the procedure is quicker and cheaper and thus should be the preferred approach.

Initial experience with long coronary stents: the changing practice of coronary angioplasty

The initial experience with the use of long coronary stents (> 30 mm in length) was analyzed retrospectively. Sixty-seven stents were deployed in 58 narrowings in 57 patients (34 AVE Microstents, 16 Nir stents, four Gianturco-Roubin II stents, and 13 Wallstents). Stents were implanted in 22 patients with unstable angina, 34 patients with stable angina, and one patient during direct angioplasty for acute myocardial infarction. Eighteen additional short stents were implanted to cover the entire length of the lesions so that an average of one and a half stents were deployed per patient. The length of the narrowings before stenting was 40 +/- 20 mm and the length of the stented segments was 45 +/- 20 mm. Stents were deployed for "bailout" in 23 narrowings, to improve suboptimal results of balloon angioplasty in 18 narrowings, and electively in 17 narrowings. Twenty of the 67 long stents were deployed in saphenous vein grafts. The success rate of stent implantation was 100%. One patient had a rupture of a saphenous vein graft after deployment of two long stents, with tamponade treated by emergency surgery. One patient had chest pain 18 hours after stent deployment; by the time he arrived at the catheterization laboratory the pain had subsided and the angiogram revealed a patent artery with normal flow. There were no other major complications during the hospital course and 1-month follow-up. We conclude that long coronary stents can be deployed successfully in native coronary arteries and vein grafts. They are useful for elective implantation and extremely helpful in bailout situations. The immediate results are excellent, but long-term outcome is awaited.