ISAR-LEFT MAIN 2: Second generation drug-eluting stents safe and effective for left main coronary artery lesions


Second-generation drug-eluting stents are safe and effective in the treatment of left main coronary artery lesions, according to results of the ISAR-LEFT MAIN 2 trial presented at the TCT congress on 24 October. Data from the study were presented by lead investigator, Julinda Mehilli, director of Catheterization Laboratories at the Medizinische Klinik I, Klinikum der Universitaet Munich, Munich, Germany.

Mehilli told delegates that patients undergoing invasive treatment of unprotected left main coronary artery lesions are often considered at high-risk of adverse cardiovascular events. The use of first generation drug-eluting stents in these lesions has previously been shown to be feasible, safe, and effective. The second-generation zotarolimus-eluting (ZES) and everolimus-eluting stents (EES), used more widely in clinical practice at present, perform very similarly in nearly all coronary artery lesions. However, their performance in unprotected left main coronary artery lesions lesions has not yet been assessed.

The ISAR-LEFT MAIN 2 trial is the first and largest performed randomised, multicentre comparison trial between zotarolimus-eluting and everolimus-eluting stents in unprotected left main coronary artery lesions. The study was designed to assess the non-inferiority of zotarolimus-eluting stents (Endeavor Resolute, Medtronic) to everolimus-eluting stents (Xience, Abbott Vascular) regarding the primary endpoint: incidence of major adverse cardiac events, which was defined as the composite of death, myocardial infarction or target lesion revascularisation at one-year follow-up. Secondary endpoints included the incidence of definite/probable stent thrombosis at one-year follow-up and angiographic restenosis at six-nine month follow-up.

In total, 650 patients with ischaemic symptoms or evidence of myocardial ischaemia in the presence of at least one ≥50% de novo stenosis located in the left main coronary artery who were unable or unwilling to undergo surgery were randomly assigned to receive ZES (n= 324) or EES (n=326).

The incidence of major adverse cardiac events was 17.5% in the ZES group and 14.3% in the EES group (p=0.25). The incidence of definite stent thrombosis was 0.6% in both groups, while probable stent thrombosis occurred in 0.3% of the ZES group and 0% of the EES group. Angiographic restenosis occurred in 21.5% of the ZES group and 16.8% of the EES group.

“Results of this trial indicate that the use of second generation drug-eluting stents in unprotected left main coronary artery lesions in relatively unselected patients is feasible, safe and effective,” said Mehilli. She added, “Both zotarolimus and everolimus stents provide similar clinical and angiographic outcomes at one-year follow-up in this high-risk patient population.”

ISAR-LEFT MAIN 2 was an investigator initiated trial without any industry funding.