Modifying angiographic syntax score according to PCI strategy: lessons learnt from ERACI IV Study

In recent years an angiographic score was introduced in clinical practice to stratified different levels of risk after percutaneous coronary interventions (PCI) with drug eluting stents. The SYNTAX score (SS) classified patients in three different risk levels and was included in revascularization guidelines that patients allocated with low SS could be equally treated with either PCI or CABG, whereas those with intermediate or high SS were better off with CABG. However, using original SS each coronary lesion with a diameter stenosis ≥50% in vessels ≥1.5 mm was scored. In ERACI IV registry we used a revascularization strategy during PCI where operators were advised to only treat lesions≥than 70% in a≥2.0 mm reference vessel; therefore, no intermediate lesions should be treated, and severe stenosis in vessels<2.0 mm was discouraged as well. If we recalculated SS using the above-mentioned operators' advices all intermediate lesions were not scored, and severe stenosis in vessels<2.0 mm were excluded for the analysis, including bifurcations, trifurcations and chronic total occlusions; after this new scoring, the original SS dropped significantly which is in accordance with the goal of complete functional revascularization strategy of the ERACI IV study and the low one year adverse events of such study. In conclusion, if we performed an SS scoring, only severe stenosis in vessels with a reference diameter ≥2.0 mm would allow a more rational assessment of coronary anatomy, and the use of a more conservative PCI strategy.