Simple Risk Score May Predict Ischemic and Bleeding Events After Percutaneous Coronary Intervention

A simple risk score that includes baseline clinical characteristics may be useful to predict risks for ischemic events and major bleeding after a percutaneous coronary intervention (PCI) with drug-eluting stents (DES), according to data recently published in the Journal of American College of Cardiology.

This risk score could also facilitate clinical decisions surrounding the optimal duration of dual-antiplatelet therapy (DAPT).

While DAPT with aspirin and clopidogrel reduces the risk of coronary thrombotic events (CTE) after PCI, it also increases the risk for major bleeding. To incorporate bleeding risk into risk scores for these patients, researchers developed and validated separate models to predict risks for thrombotic and bleeding events that occur outside of the hospital after PCI with DES.

Researchers selected 4190 patients from the PARIS registry (Patterns of Nonadherence to Anti-Platelet Regimen in Stented Patients) who underwent PCI with with DES, after excluding patients who were not discharged with DAPT, those who received bare-metal stents (BMS), and those who experienced in-hospital events.

They developed risk scores to predict CTE, which was defined as “the composite of stent thrombosis or myocardial infarction,” and major bleeding, which was defined as “the occurrence of Bleeding Academic Research Consortium type 3 or 5 bleed.”

After 2 years of follow-up, CTEs occurred in 151 patients (3.8%) and major bleeding occurred in 133 (3.3%).

The results revealed that acute coronary syndrome, prior revascularization, diabetes, renal dysfunction, and current smoking status were all independent predictors of CTEs. For major bleeding, independent predictors included older age, body mass index, use of triple therapy at discharge, anemia, current smoking status, and renal dysfunction.

Discrimination was moderate and there was adequate calibration for the total cohort for both the CTE model (C statistic: 0.70; GOF [goodness-of-fit] chi-square: 9.7; P=.37) and the major bleeding model (C statistic: 0.72; GOF chi-square: 10.4; P=.32).

“We found that clinical factors alone, rather than procedural parameters, predicted risks for CTE,” the authors noted. “This results contrasts with other studies highlighting the importance of lesion complexity, stent size, or stent length on risk for ST [stent thrombosis.”

“In part, these differences may be due to the relatively low frequency of ST as a component of CTE in our study or the prevalent use of safe second-generation DES in most PARIS participants. Alternatively, it is plausible that thrombotic risk factors are not static but dynamic over time.”

Future studies should assess strategies that combine periprocedural risk assessment with registry data into clinical decisions regarding the duration and intensity of DAPT after PCI.

Reference

Baber U, Mehran R, Giustino G, et al. Coronary thrombosis and major bleeding after PCI with drug-eluting stents: risk scores from PARIS. J Am Coll Cardiol. 2016;67(19): doi: 10.1016/j.jacc.2016.02.064.