Time to Coronary Angiography and Outcomes Among Patients With High-Risk Non–ST-Segment–Elevation Acute Coronary Syndromes

Abstract

Background-Optimal timing for an early invasive strategy in patients with non-ST-segment-elevation acute coronary syndrome remains unclear. We evaluated the relationship between time from hospital admission to coronary angiography and outcomes in high-risk patients with non-ST-segment-elevation acute coronary syndrome who underwent angiography within 48 hours of admission. Methods and Results-Data from 10 027 patients enrolled in the Superior Yield of the New Strategy of Enoxaparin, Revascularization, and Glycoprotein IIb/IIIa Inhibitors (SYNERGY) trial were analyzed. Patients were grouped by 6-hour intervals of time from hospital admission to coronary angiography. Primary outcomes were 30-day death or myocardial infarction, in-hospital Thrombolysis In Myocardial Infarction (TIMI) and Global Utilization of Streptokinase and Tissue Plasminogen Activator for Occluded Coronary Arteries (GUSTO) major bleeding, and blood transfusion. Adjusted estimates of event rates were obtained by use of a multivariable methodology that included possible confounders through baseline and accounted for propensity of time to angiography. The landmark method was used to calculate odds ratios and 95% confidence intervals of outcomes for each time period adjusted for baseline and postbaseline clinical events. Overall, 9216 patients (92%) underwent angiography, 6352 (63%) within 48 hours. Unadjusted and adjusted rates of death/myocardial infarction increased with increasing time to angiography. The adjusted odds ratio for death/myocardial infarction in patients receiving angiography in Ͻ6 hours was 0.56 (95% confidence interval 0.41 to 0.74), whereas after 30 hours, there was no significant benefit compared with further delayed angiography. Major bleeding and transfusion did not vary significantly across time-to-angiography intervals. Conclusions-A decrease in the time to coronary angiography was associated with fewer ischemic outcomes and no increase in bleeding. Randomized clinical trials are needed to provide definitive evidence on optimal timing of coronary angiography but are difficult to design and conduct. Ongoing trials should instead clarify whether delaying angiography to administer aggressive upstream antithrombotic therapies is effective in the current setting of non-ST-segmentelevation acute coronary syndrome management.

Early invasive strategy and outcomes of non-ST-elevation acute coronary syndrome patients: is time really the major determinant?

“…Moreover, the results of our study also are in accord with those of a recent metanalysis in which no significant difference in mortality and occurrence of myocardial infarction was observed between ACS patients treated with a delayed versus an early invasive approach [17]. However, our findings do not agree with those reported by Tricoci et al who found, in a larger number of patients, a decreased risk in the combined end-point mortality or myocardial infarction at 1-month follow-up in patients treated with an early invasive strategy [9]. Our results are also different from those reported by the ISAR-COOL investigators who found that a ''very early'' invasive strategy was associated with a significantly better outcome [18].…”

“…However, the optimal timing for coronary angiography in such patients is still unknown [8,9], and in daily practice, there is a wide variation in interpreting the term ''early''. In some hospitals, ACS patients are rapidly transferred from the Emergency Department (ED) to the catheterization laboratory, whereas in others they may wait for coronary angiography up to a week, as suggested by FRISC II investigators [3].…”

Landmark Analysis at the 25-Year Landmark Point

“…From the 6 studies appearing in The Journal of the American Medical Association, 5 were on cardiology subjects, including the 2007 article by Eisenstein et al 2 A recent report evaluating the effect of coronary angiography as a time-dependent variable on outcome used an interesting approach and graphical illustration with "repeated" landmark analyses in sequential 6-hour time intervals. 18 Time from hospitalization to angiography was broken into 6-hour time periods. Odds ratios and 95% confidence intervals of delayed outcome (30-day death/myocardial infarction and in-hospital major bleeding) for each 6-hour time period were estimated from logistic regression models and presented graphically for up to 48 hours from hospital admission.…”

Part 9: Acute Coronary Syndromes

“…Four randomized, controlled trials (RCTs, LOE 1), 330 -332,333 3 meta-analyses (LOE 1), 334 -336 6 nonrandomized control trials (LOE 2 to 4), [337][338][339][340][341][342][343][344] and 5 additional studies (LOE 4 to 5) [345][346][347][348][349] did not demonstrate a difference for outcomes among in-hospital patients given enoxaparin compared with UFH.…”