Predictive utility of residual SYNTAX score for clinical outcomes after successful primary percutaneous coronary intervention.

Background: In patients presenting with ST-segment elevation myocardial infarction (STEMI), the prevalence of having concomitant severe non-culprit lesion(s) is ≥40%. While timely primary PCI (pPCI) for the culprit lesion is the standard practice, management of the non-culprit lesions remains unsettled.

Results: This prospective multi-center observational study recruited 492 acute STEMI patients who underwent successful pPCI for the culprit lesion. Culprit-only versus complementary non-culprit lesion(s) PCI (either immediate or staged during the same hospital stay) was according to the operator's discretion. Clinical, echocardiographic, and angiographic data were collected and tabulated. The residual SYNTAX score (rSS) was completed by the time of discharge considering the residual lesions after all in-hospital revascularization procedures. Through a minimum follow-up of 12 months, older age, presentation with heart failure Killip class ≥ II, lower estimated glomerular filtration rate (eGFR) on admission, lower left ventricular ejection fraction (LVEF), and higher rSS by discharge were significantly associated with recurrent MACE. In multivariate regression analysis, Killip class ≥ II, LVEF, and rSS were found to be independent predictors for recurrent MACE. In the Receiver Operating Characteristics curve, an rSS of >8 had a sensitivity of 70.1%, and specificity of 75.3% to predict 1-year MACE.

Conclusions: Residual syntax score proved to be an independent predictor for recurrent MACE through the subsequent year post STEMI. Patients with rSS >8 seem to be at the highest risk for adverse events and are likely to be the most deserving for completing revascularization to reduce the disease burden.