Comparison of Long-Term Clinical Outcomes of Elective Percutaneous Coronary Intervention Between Complex and High-risk Intervention in Indicated Patients (CHIP) versus Non-CHIP

Recently, there has been a growing interest in complex and high-risk intervention in indicated patients (CHIP) in the contemporary percutaneous coronary intervention (PCI). CHIP is composed of the following 3 factors: (1) patient factors, (2) complicated heart disease, and (3) complex PCI. However, there are few studies that investigated the long-term outcomes of CHIP-PCI. The purpose of this study was to compare the incidence of long-term major adverse cardiovascular events (MACEs) among the definite CHIP, possible CHIP, and non-CHIP groups in complex PCI. We included 961 patients and divided them into the definite CHIP (n = 129), the possible CHIP (n = 369), and the non-CHIP groups (n = 463). During the median follow-up duration of 573 days (quartile 1:226 days to quartile 3:1,165 days), a total of 189 MACE were observed. The incidence of MACE was highest in the definite CHIP group, followed by the possible CHIP group, and lowest in the non-CHIP group (p = 0.001). Definite CHIP (vs non-CHIP: odds ratio 3.558, 95% confidence interval 2.249 to 5.629, p <0.001) and possible CHIP (vs non-CHIP: odds ratio 2.260, 95% confidence interval 1.563 to 3.266, p <0.001) were significantly associated with MACE after controlling for confounding factors. Among CHIP factors, active malignancy, pulmonary disease, hemodialysis, unstable hemodynamics, left ventricular ejection fraction, and valvular disease were significantly associated with MACE. In conclusion, the incidence of MACE in complex PCI was highest in the definite CHIP group, followed by the possible CHIP group, and lowest in the non-CHIP group. The concept of CHIP should be recognized to predict the long-term MACE in patients who undergo complex PCI.