During daytime working hours, outcomes may be worse when percutaneous coronary intervention (PCI) is performed later in the day because of operator fatigue and differences in process of care.

Using the APPROACH database, we analyzed 2,492 consecutive nonurgent PCI procedures performed during working hours. Patients undergoing PCI for acute coronary syndromes were excluded. Patients were separated into 2 groups based on whether PCI was started in the morning (7:00 am-12:00 pm, n = 1,446) or after noon (12:01 pm-6:00 pm, n = 1,037). Outcomes included procedural complications; target vessel revascularization (TVR); and death at 7 days, 30 days, and 1 year.

Patients undergoing PCI in the afternoon were more likely to have heart failure, reduced ejection fraction, and Canadian Cardiovascular Society class IV or atypical angina symptoms; more likely to be inpatients; less likely to have stable angina; and less likely to receive glycoprotein IIb/IIIa inhibitors. Patients undergoing PCI in the afternoon had significantly higher unadjusted rates of the composite of death and TVR at 7 days (0.9% vs 0.3%, P = .04) and 30 days (2.0% vs 1.0%, P = .04) and death at 1 year (2.2% vs 1.1%, P = .03) compared with PCI performed in the morning. After multivariate adjustment, the differences in the composite of death and TVR at 30 days and at 1 year were not statistically significant.

Patients undergoing nonurgent PCI during working hours after noon had higher rates of TVR in the first 30 days and death at 1 year. Further study is required to determine whether patient characteristics, operator fatigue, differences in process of care, or a combination of these factors accounts for the difference in outcomes.