SYNTAX score predicts clinical outcomes in PCI patients
MedWire News: The SYNTAX score independently predicts 1-year clinical outcomes in patients with non-ST segment elevation acute coronary syndromes (NSTE ACS) undergoing percutaneous coronary intervention (PCI), research indicates.
Gregg Stone (Columbia University Medical Center, New York, USA) and colleagues conducted a substudy of the Acute Catheterization and Urgent Intervention Triage StrategY (ACUITY) trial. They found that in patients with moderate- and high-risk NSTE ACS undergoing PCI, the SYNTAX score was an independent predictor of 1-year cardiac mortality, myocardial infarction (MI), and target vessel revascularization (TVR).
The SYNTAX (Synergy Between PCI with Taxus and Cardiac Surgery) score (SS) is an angiographic scoring system which effectively risk-stratifies patients with left main and triple-vessel coronary disease, they explain.
"As such, the SS may be a useful tool for risk stratification in this [NSTE ACS] patient population," they write in the Journal of American Cardiology.
In the ACUITY trial, NSTE ACS patients were randomly assigned to receive heparin plus a glycoprotein IIb/IIIa inhibitor (GPI), or bivalirudin monotherapy with bailout GPI use. After angiography, patients underwent PCI, CABG or medical therapy, depending on their coronary anatomy.
In the present substudy, Stone et al calculated SS for 2627 ACUITY patients using the SYNTAX algorithm. They then stratified patients according to SS tertiles of <7 (n=854), ≥7 and <13 (n=825), and ≥13 (n=948).
The findings showed that patients in the highest tertile were older, and more likely to have diabetes, renal dysfunction, baseline troponin elevation, ST-segment deviation, higher Thrombolysis in Myocardial Infarction (TIMI) risk score, and lower left ventricular ejection fraction (LVEF) than those in the lower two tertiles.
At 1-year follow-up, 2.4% of patients in the overall cohort had suffered all-cause death, 1.3% suffered cardiac death, 9.3% had MI, and 8.1% had TVR. The team found that after stratifying by SS, these outcomes were significantly more common in the highest (third) tertile than in the first (p=0.001, p<0.0001 for cardiac death and MI, respectively) and second tertiles (p=0.003, p=0.005, p=0.002, respectively).
After multivariable adjustment, SS was an independent predictor of all-cause death (p=0.005), cardiac death (p=0.0002), MI (p<0.0001), and TVR (p<0.0001).
In patients with a higher SS (≥13), the risks for all-cause death, cardiac death, and MI were increased at both 30 days (hazard ratio [HR]=3.11, 3.80, 2.00, respectively) and 1 year (HR=2.43, 7.16, 1.42, respectively) relative to patients with lower SS (<13), but the association between MI at 1 year and SS was nonsignificant. TVR was also increased, 2.55 fold, in this group within the first 30 days.
Further analysis showed that the predictive value of increased SS was consistent among the elderly, as well as patients with diabetes, renal dysfunction, and low LVEF.
"The present study thus demonstrates that in addition to clinical variables, angiographic factors [such as SS] also are important for risk-stratifying NSTE ACS patients undergoing PCI," conclude Stone et al.
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By Piriya Mahendra