Abstract 2566: Late and Very Late Stent Thrombosis following Elective Drug Eluting Stent Implantation in Unprotected Left Main Coronary Artery: a Multicentre Registry

The long-term safety of drug-eluting stent (DES) implantation in the treatment of unprotected left main coronary artery (LMCA) stenosis is still a matter of debate. Some concerns have been recently raised regarding the risk of late and very late stent thrombosis (ST). Methods: All consecutive patients (pts) who had sirolimus (SES, Cypher, Cordis, Johnson and Johnson Company, Warren, NJ) or paclitaxel-eluting stent (PES, Taxus, Boston Scientific, Natick, MA) electively implanted in de novo lesions on LMCA between March 2002 and June 2006 were included in this multicentre registry. Stent thromboses were defined according to Academic Research Consortium (ARC) definitions. Results Five-hundred and thirty-four consecutive patients were analyzed: 357 patients were treated with SES, 168 with PES and 9 with both of them. One-hundred and thirty-eight (25.8%) patients were diabetics, 171 (32.0%) unstable angina, mean age 62.4 ± 11.4 years, EF 54.1 ± 11.2 %. Distal location occurred in 417 (78.0%) of the patients. Fifty-seven (10.6%) patients had a peri-procedural myocardial infarction (defined as CK-MB elevation ≥3 ULN). At 1044 ± 361 day clinical follow-up, 32 (5.9%) patients died: 23 (4.3%) were adjudicated as cardiac according to ARC definition. One patient had an acute ST (with cardiogenic shock treated with CABG), 1 a sub-acute ST (occlusion of circumflex artery treated with PCI) and 1 a late definite ST (in the left anterior descending artery with MI at 3 months while on antiplatelet therapy). None of the patients had a very late definite ST. In the Table are reported probable and possibile ST. Conclusions Treatment of LMCA stenosis with DES appears safe at long-term clinical follow-up with a 0.6% incidence of definite and probable ST at a median follow-up of almost 3 years. Table.