Rapamycin-eluting Stents for the Treatment of Unprotected Left Main Coronary Disease

Background: Conventional bare stents have been used to treat unprotected left main (LM) coronary artery stenosis. However, restenosis remains the main limitation. Since rapamycin-eluting stents (RES) appear to inhibit neointimal proliferation, their application to this specific site seems promising.

Methods: Since May 2002, we have studied a series of 52 patients with LM lesions treated with RES. Forty-seven patients presented with de novo stenoses, and 5 had in-stent restenosis; 19 patients required combined stent treatment for other remote lesions in the coronary tree, 6 of them at the level of proximal right coronary artery. The RES was implanted directly at the LM in 39 patients; 13 others needed predilation. Once deployed, the RES was overexpanded with short balloons adjusted to the LM length in 44 patients. Quantitative coronary angiograms were analyzed in the same view before and immediately after treatment and at follow-up. Patients were followed-up closely and new cardiac catheterization was scheduled at 6-month evaluation or earlier in the presence of symptoms. At follow-up study, quantitative coronary angiography and motorized intravascular ultrasound analyses were performed in 35 (67%) patients.

Results: Primary success was obtained in 50 patients (96%). Two patients (4%) developed a non-Q-wave myocardial infarction. All patients were symptom-free at discharge. After a mean follow-up of 12 +/- 4 months, 50 patients (96%) remain asymptomatic. No late death or acute thrombosis have been recorded. Two patients became symptomatic 2 and 4 months after treatment, respectively. One had restenosis at a remote site, while the other had in-segment restenosis. None of the remaining 33 angiographically evaluated patients developed restenosis at any site. Target lesion revascularization was 1/52 (2%).

Conclusions: Although longer-term follow-up studies are needed, the tailored treatment of coronary lesions located at the LM by overexpanded RES is feasible and safe. Midterm results seem promising, which might help to shift the orientation of patient management from surgical to percutaneous revascularization.