Objective: To identify patients undergoing complex, high-risk indicated percutaneous coronary intervention (CHIP-PCI) and compare their outcomes with non-CHIP patients. We created a CHIP score to risk stratify these patients.
Background: Risk stratification of PCI patients remains difficult because most scoring systems reflect hemodynamic instability and predict early mortality.
Methods: CHIP-PCI was defined as any of the following: age >80 years; ejection fraction <30%; dialysis; prior bypass surgery; treatment of left main trunk; chronic total occlusion; or >2 lesions in >1 coronary artery. The primary endpoint was 1-year all-cause mortality. Logistic regression identified independent predictors of 1-year mortality and the odds ratios (ORs) for those predictors were used to create a CHIP score. Patients were then classified as low, intermediate, and high risk.
Results: Among 4478 patients, a total of 1730 (38.6%) were CHIP. There were 85 deaths (2.2%) at 1 year (4.1% in CHIP patients and 1.0% in non-CHIP patients; P<.001). CHIP-PCI was an independent predictor of mortality (OR, 2.57; 955 confidence interval, 1.52-4.32; P<.001). Four CHIP criteria were independent predictors of mortality: age >80 years (3 points); dialysis (6 points); ejection fraction <30% (2 points); and number of lesions treated >2 (2 points). Accordingly, there were 2752 low-risk (score of 0), 889 intermediate-risk (score of 2-3), and 267 high-risk patients (score of 4-13). The 1-year mortality rates among these 3 groups were 1.24%, 2.47%, and 10.86%, respectively (P<.001).
Conclusion: Compared with non-CHIP, CHIP-PCI is associated with increased risk of 1-year mortality, which is particularly evident among those fulfilling >1 CHIP criterion.
Keywords: CHIP-PCI; coronary disease; mortality.