Impact of residual SYNTAX score on clinical outcomes after incomplete revascularisation percutaneous coronary intervention: a large single-centre study

Aims: This study aimed to assess the prognostic capacity of the residual SYNTAX score (rSS) in a large cohort of patients undergoing percutaneous coronary intervention (PCI) in clinical practice. Methods and results: Ten thousand three hundred and forty-four (10,344) consecutive patients were prospectively enrolled. Complete revascularisation (CR; rSS= 0), reasonable incomplete revascularisation (RICR; 0<rSS <= 8), and ICR (rSS>8) were achieved in 5,375 (51.9%), 3,401 (32.9%), and 1,568 (15.2%) patients, respectively. During two-year follow-up, ICR patients had the highest incidence of major adverse cardiovascular and cerebrovascular events (MACCE; 20.0% vs. 13.6% vs. 8.7%, respectively; p<0.001). There was no difference in the incidence of all-cause death (1.2% vs. 1.0%; p=0.45), cardiac death (0.6% vs. 0.5%; p=0.31), and myocardial infarction (2.2% vs. 1.6%; p=0.07) between RICR and CR patients, while the rate of repeat revascularisation was significantly higher in RICR patients (9.8% vs. 5.8%; p<0.001). After multivariate analysis, rSS was an independent predictor of two-year cardiac death, myocardial infarction, revascularisation, and MACCE (p<0.05). Conclusions: Despite an increase in revascularisation, RICR was associated with a similar mortality and myocardial infarction to CR patients. rSS is a prognostic indicator after PCI in daily practice, and may be used to determine a reasonable level of revascularisation.