Very long-term prognostic value of clinical SYNTAX score in patients undergoing percutaneous coronary intervention for left main coronary artery disease

Abstract

Abstract Background Recently, long-term prognostic value of SYNTAX score (SS) has been validated in patients with left main coronary artery disease (LMCA). However, the ability of clinical SYNTAX score (CSS) to predict very long-term outcomes in patients undergoing percutaneous coronary intervention (PCI) for LMCA has not been fully investigated yet. Purpose We aimed to validate the impact of CSS on very long-term outcomes in patients undergoing PCI for LMCA. Methods Between June 2006 and December 2012, 279 patients underwent unprotected LMCA PCI were analyzed. The SS for each patient was calculated by scoring all coronary lesions using SS algorithm. CSS was calculated by multiplying the SS to an ACEF score (age/left ventricular ejection fraction + 1 if serum creatinine>2mg/dL). Major adverse cardiac events (MACEs) were defined as death, non-fatal myocardial infarction, and revascularizations. Mean follow-up duration was 2,529±1664 days. Results The CSS (26.8±11.9 versus 39.9±26.1, p<0.001) as well as SS (23.2±6.9 versus 25.8±7.9, p=0.003) was significantly higher in patients with MACEs. Area under the curve for MACEs (0.672 versus 0.599, p=0.0023) and mortality (0.744 versus 0.626, p<0.0001) of CSS was significantly higher compared with those of SS (Figure 1). The CSS significantly improved the reclassification and the integrated discrimination of patients compared to SS. Log CSS was an independent predictor for MACEs (hazard ratio [HR] 5.37, 95% confidence interval [CI] 1.98 – 14.61; p = 0.006) and mortality (HR 11.69, 95% CI 3.30 – 41.31; p < 0.001). When patients were categorized into 3 groups according to tertiles of CSS (Low CSS ≤ 22, 22 < Mid CSS ≤ 34, High CSS > 34), patients in the highest CSS tertile had significantly higher rates of MACEs (log-rank p<0.001) and mortality (log-rank p<0.001) compared with those in the lower 2 tertiles (Figure 2). The highest CSS tertile was an independent predictor for MACEs (HR 2.33, 95% CI 1.42 – 3.82; p = 0.001) and mortality (HR 5.66, 95% CI 2.20 – 14.57; p < 0.001). Conclusions The CSS is useful to predict very long-term clinical outcome in patients underwent unprotected LMCA PCI.