Inter- and intra-observer variability for assessment of the synergy between percutaneous coronary intervention with TAXUS and cardiac surgery (SYNTAX) score and association of the SYNTAX score with clinical outcome in patients undergoing unprotected left main stenting in the real world.

BACKGROUND: The Synergy Between Percutaneous Coronary Intervention With TAXUS and Cardiac Surgery (SYNTAX) score was proposed as a method to evaluate the complexity of coronary anatomy. However, the reproducibility of assessment for the SYNTAX score in unprotected left main coronary artery (ULMCA) disease has not yet been adequately evaluated. The purpose of this study is to assess inter- and intra-observer variability for the assessment of the SYNTAX score in patients undergoing ULMCA stenting in daily clinical practice. METHODS AND RESULTS: The SYNTAX score of 101 consecutive patients who underwent ULMCA stenting with sirolimus-eluting stent was independently assessed by 2 experienced interventional cardiologists. One of the 2 cardiologists evaluated all the cases again 6 months after the initial assessment. The κ value for inter-observer variability in estimating the SYNTAX score was 0.62 according to the dichotomized analysis (≥ 33, < 33) and 0.58 according to the tertile analysis (< 23, 23 ≤ - < 33, ≥ 33), while the intra-observer variability was 0.78 and 0.69, respectively. Patients with a high SYNTAX score (≥ 33, n = 55) compared with those with low or intermediate score (< 33, n = 46) had a significantly higher rate of target-lesion revascularization (TLR) of the ULMCA lesion at 2 years (24% vs. 4.4%, P = 0.01). CONCLUSIONS: Both inter- and intra-observer variability for estimating the SYNTAX score were within an acceptable range and a high SYNTAX score showed a higher rate of TLR in patients undergoing ULMCA stenting in daily clinical practice.

Long-term clinical outcomes after sirolimus-eluting stent implantation for unprotected left main coronary artery disease.

Previous studies reporting long-term (≥5 year) clinical outcome in patients with unprotected left main coronary artery (LMCA) disease undergoing drug-eluting stent (DES) implantation are currently limited, although late adverse events beyond 1 year are one of the major concerns of DES. We evaluated long-term clinical outcomes in 134 consecutive patients who underwent sirolimus-eluting stents (SES) for unprotected LMCA lesion in a single center from 2004 to 2009. The median follow-up duration was 3.8 (range: 0.5-7.9) years. Eight patients suffered from serious cardiovascular events potentially related to LMCA lesion (primary outcome measure) (sudden cardiac death: N = 5, emergent coronary revascularization for the LMCA lesion: N = 2, and acute congestive heart failure related to LMCA lesion: N = 1) with the cumulative 5-year incidence of only 4.4 %. The cumulative 5-year incidence of all-cause death, cardiac death, target vessel myocardial infarction, definite stent thrombosis, and target-lesion revascularization was 26.5, 8.1, 0, 0, and 12.9 %, respectively. In a subgroup analysis, the cumulative incidence of the primary outcome measure was significantly higher in patients with 2-stenting (N = 27) than in patients with 1-stenting (N = 107) (14.0 and 2.2 %, P < 0.001). All 8 patients with serious adverse events had a true bifurcation lesion and 5 patients received 2-stenting for the LMCA lesion. SES implantation in patients with unprotected LMCA lesion was associated with a favorable long-term outcome with acceptably low rate of serious adverse event potentially related to LMCA lesion. However, complex LMCA lesions necessitating 2-stenting strategy might be associated with higher risk for serious adverse events.