Timing of angiography with a routine invasive strategy and long-term outcomes in non-ST-segment elevation acute coronary syndrome: a collaborative analysis of individual patient data from the FRISC II (Fragmin and Fast Revascularization During Instability in Coronary Artery Disease), ICTUS (Invasive Versus Conservative Treatment in Unstable Coronary Syndromes), and RITA-3 (Intervention Versus Conservative Treatment Strategy in Patients With Unstable Angina or Non-ST Elevation Myocardial Infarction) Trials.

OBJECTIVES: This study sought to investigate long-term outcomes after early or delayed angiography in patients with non-ST-segment elevation acute coronary syndrome (nSTE-ACS) undergoing a routine invasive management.

BACKGROUND: The optimal timing of angiography in patients with nSTE-ACS is currently a topic for debate.

METHODS: Long-term follow-up after early (within 2 days) angiography versus delayed (within 3 to 5 days) angiography was investigated in the FRISC-II (Fragmin and Fast Revascularization During Instability in Coronary Artery Disease), ICTUS (Invasive Versus Conservative Treatment in Unstable Coronary Syndromes), and RITA-3 (Intervention Versus Conservative Treatment Strategy in Patients With Unstable Angina or Non-ST Elevation Myocardial Infarction) (FIR) nSTE-ACS patient-pooled database. The main outcome was cardiovascular death or myocardial infarction up to 5-year follow-up. Hazard ratios (HR) were calculated with Cox regression models. Adjustments were made for the FIR risk score, study, and the propensity of receiving early angiography using inverse probability weighting.

RESULTS: Of 2,721 patients originally randomized to the routine invasive arm, consisting of routine angiography and subsequent revascularization if suitable, 975 underwent early angiography and 1,141 delayed angiography. No difference was observed in 5-year cardiovascular death or myocardial infarction in unadjusted (HR: 1.06, 95% confidence interval [CI]: 0.79 to 1.42, p=0.61) and adjusted (HR: 0.93, 95% CI: 0.75 to 1.16, p=0.54) Cox regression models.

CONCLUSIONS: In the FIR database of patients presenting with nSTE-ACS, the timing of angiography was not related to long-term cardiovascular mortality or myocardial infarction. (Invasive Versus Conservative Treatment in Unstable Coronary Syndromes [ICTUS]; ISRCTN82153174. Intervention Versus Conservative Treatment Strategy in Patients With Unstable Angina or Non-ST Elevation Myocardial Infarction [the Third Randomised Intervention Treatment of Angina Trials (RITA-3)]; ISRCTN07752711).