Effects of ON-hours versus OFF-hours admission on outcome in patients with myocardial infarction and cardiogenic shock: Results from the CULPRIT-SHOCK trial

Background: The management of patients with acute myocardial infarction complicated by cardiogenic shock is highly complex, and outcomes may depend on the time of hospital admission and subsequent intervention (ie, ON-hours versus OFF-hours). The CULPRIT-SHOCK trial (Culprit Lesion Only PCI Versus Multivessel PCI in Cardiogenic Shock) demonstrated superior outcome for culprit-lesion-only versus immediate multivessel percutaneous coronary intervention in patients presenting with acute myocardial infarction, multivessel disease, and cardiogenic shock. However, it is unknown whether the time of hospital admission affects the overall outcome of these high-risk patients. Methods: We analyzed patients from the CULPRIT-SHOCK trial with respect to the time of hospital admission. We divided patients in ON-hours and OFF-hours groups and further stratified them according to their individual revascularization strategy. Outcome measures consisted of a composite end point of death or renal-replacement therapy within 30 days and mortality within 1 year. Results: Out of 686 patients randomized in the CULPRIT-SHOCK trial, 444 patients (64.7%) presented during ON-hours, whereas 242 patients (35.3%) presented during OFF-hours. Death or renal-replacement therapy at 30 days occurred to a similar extent in patients admitted during ON-hours (51.0%) and OFF-hours (50.0%; P=0.80). Similarly, 1-year mortality was not affected by the time of hospital admission (54.4% ON-hours versus 51.7% OFF-hours, P=0.49). Regardless of admission time, patients had a benefit from culprit-lesion-only as compared to immediate multivessel percutaneous coronary intervention. The composite end point at 30 days occurred in 45.1% versus 57.6% of patients admitted ON-hours and in 47.7% versus 51.9% of patients admitted OFF-hours (P^interaction=0.29). Death within 1 year occurred in 49.4% versus 60.0% of patients admitted during ON-hours and in 51.4% versus 51.9% of patients admitted OFF-hours (P^interaction=0.20). Conclusions: Among patients with myocardial infarction and cardiogenic shock, the risk of death or renal-replacement therapy at 30 days, and mortality at 1 year did not differ significantly according to the time of hospital admission.