Residual SYNTAX score II and complex percutaneous coronary interventions.

To the Editor,

Salvatore et al. [1] reported that SYNTAX score II (SS-II) might represent a useful tool to predict clinical events not only in ideal stable patients, but also in an unrestricted, real world population of patients with acute coronary syndrome and severe coronary artery disease (CAD) undergoing percutaneous coronary intervention (PCI).

SS-II briefly contains six clinical variables (age, sex, creatinine clearance, peripheral vascular disease, chronic obstructive pulmonary disease, and left ventricular ejection fraction) and two anatomical variables (anatomical SS and unprotected left main CAD) [2]. Residual SS (rSS) was designed and validated to quantify the burden of residual CAD after PCI. SS-II indicated a superior predictability for long-term mortality compared with SS [3]. SS-II may be a more useful tool than SS for predicting no-reflow phenomenon after primary PCI [4]. Additionally, prognostic significance of SS-II is widening, and it is applicable for clinical utility in valvular heart disease [5].

Residual SS-II, including rSS, postprocedural left ventricular ejection fraction, and postprocedural creatinine clearance might be a usefull tool to predict major adverse cardiac events and all-cause mortality. In this context, correlation of this study’s result with residual SS-II might be beneficial.