Impact of pre-angioplasty antithrombotic therapy administration on coronary reperfusion in ST-segment elevation myocardial infarction: Does time matter?

Upstream anticoagulation in patients with ST-segment elevation myocardial infarction: a systematic review and meta-analysis

BACKGROUND AND AIM

Parenteral anticoagulation is recommended for all patients presenting with ST-segment elevation myocardial infarction (STEMI) during primary percutaneous coronary intervention (PPCI). Whether upstream anticoagulation improves clinical outcomes is not well established. We conducted a systematic review and meta-analysis of contemporary evidence on parenteral anticoagulation timing for STEMI patients.

METHODS

We performed a systematic search of electronic databases (PubMed, CENTRAL, and Scopus) until December 2022. Studies were eligible if they (a) compared upstream anticoagulation with administration at the catheterization laboratory and (b) enrolled patients with STEMI undergoing PPCI. Efficacy outcomes included in-hospital or 30-day mortality, in-hospital cardiogenic shock (CS), and TIMI flow grade pre- and post-PPCI. Safety outcome was defined as in-hospital or 30-day major bleeding.

RESULTS

Overall, seven studies were included (all observational), with a total of 69,403 patients. Upstream anticoagulation was associated with a significant reduction in the incidence of in-hospital or 30-day all-cause mortality (OR 0.61; 95% CI 0.45-0.81; p < 0.001) and in-hospital CS (OR 0.68; 95% CI 0.58-0.81; p < 0.001) and with an increase in spontaneous reperfusion (pre-PPCI TIMI > 0: OR 1.46; 95% CI 1.35-1.57; p < 0.001). Pretreatment was not associated with an increase in major bleeding (OR 1.02; 95% CI 0.70-1.48; p = 0.930).

CONCLUSIONS

Upstream anticoagulation was associated with a significantly lower risk of 30-day all-cause mortality, incidence of in-hospital CS, and improved reperfusion of the infarct-related artery (IRA). These findings were not accompanied by an increased risk of major bleeding, suggesting an overall clinical benefit of early anticoagulation in STEMI. These results require confirmation in a dedicated randomized clinical trial.

Pretreatment with heparin in patients with ST-segment elevation myocardial infarction: a report from the Swedish Coronary Angiography and Angioplasty Registry (SCAAR)

BACKGROUND

Unfractionated heparin (UFH) is frequently administered before percutaneous coronary intervention (PCI) in patients with ST-segment elevation myocardial infarction (STEMI).

AIMS

The aim of the study was to investigate if pretreatment with UFH prior to arrival at the catheterisation laboratory affects coronary artery occlusion, mortality, and in-hospital major bleeding in patients with STEMI undergoing PCI.

METHODS

Patients with a first STEMI event undergoing PCI between 2008 and 2016 were extracted from the Swedish Coronary Angiography and Angioplasty Registry. Risk ratios for UFH pretreatment versus no pretreatment regarding coronary artery occlusion at presentation in the catheterisation laboratory, 30-day mortality, and bleeding were obtained using adjusted Poisson regression models with robust standard errors. Analyses of propensity score (PS)-matched groups were performed to obtain absolute risk differences.

RESULTS

In all, 41,631 patients were included, 16,026 (38%) with and 25,605 (62%) without UFH pretreatment. Adjusted risk ratios were 0.89 (95% confidence interval [CI]: 0.87 to 0.90) for coronary artery occlusion, 0.87 (0.77 to 0.99) for mortality, and 1.01 (0.86 to 1.18) for bleeding. In the PS-matched analyses, the absolute risk differences were -0.087 (-0.074 to -0.099) for coronary artery occlusion, -0.011 (-0.017 to -0.0041) for mortality, and 0 (-0.0052 to 0.0052) for bleeding.

CONCLUSIONS

Pretreatment with UFH was associated with a reduction in coronary artery occlusion among patients with STEMI, with a number needed to treat (NNT) of 12, without increasing the risk of major in-hospital bleeding. Regarding mortality, a reduction was found with UFH pretreatment, with an NNT of 94, but this effect was not robust over all sensitivity analyses and residual confounding cannot be excluded.