Efficacy and safety of prehospital administration of unfractionated heparin, enoxaparin or bivalirudin in patients undergoing primary percutaneous coronary intervention for ST-segment elevation myocardial infarction: Insights from the ORBI registry

The effect of ASA, ticagrelor, and heparin in ST-segment myocardial infarction patients with prolonged transport times to primary percutaneous intervention

OBJECTIVES

To investigate the effects of early upstream antithrombotic therapy administration (ATTA) in ST-segment elevation myocardial infarction (STEMI) patients with prolonged transport times to primary percutaneous intervention (PPCI) on major clinical outcomes.

BACKGROUND

It remains unclear whether early upstream administration of aspirin, ticagrelor, and unfractionated heparin (UFH) confers additional benefits compared with in-hospital administration.

METHODS

Between 2015 and 2018, we performed PPCI in 709 included consecutive STEMI patients. We compared 482 STEMI patients who received aspirin, ticagrelor, and UFH loading in a non-PCI capable spoke hospital before transfer (NPHT) versus 227 prehospital triage setting (PTS) STEMI patients who received in-ambulance aspirin, followed by ticagrelor and UFH in the hub catheterization laboratory. The primary outcome was the presence of a pre-PPCI TIMI flow 2-3 in the infarct related artery (IRA). The secondary outcomes included definite acute stent thrombosis and hemorrhagic complications.

RESULTS

The median times from ticagrelor and heparin administration to angiography in the NPHT group and the PTS group were 80.5 min (Interquartile Range (IQR) 68.5-94) and 10 min (IQR 5-15) respectively (p < .0001). Using inverse probability of treatment weighting to minimize heterogeneity between groups, we showed significant differences for the primary outcome (44.6 versus 18.5%, p < .0001) and for definite acute stent thrombosis (0.6 versus 2.6%, p = .03), with no difference in the combined in-hospital BARC 2-5 bleeding events (1.9 versus 3.5%, p = .18) in the NPHT versus the PTS group, respectively.

CONCLUSION

In this single-center retrospective cohort study, after adjusting for baseline covariates, early upstream ATTA with aspirin, ticagrelor, and UFH was associated with greater pre-PPCI TIMI flow and less definite acute stent thrombosis in STEMI patients, without increased bleeding risk.

Survival in Patients with Paramedic-Identified ST-Segment Elevation Myocardial Infarction

BACKGROUND

Field identification and treatment of ST-segment elevation myocardial infarction (STEMI) by paramedics is an important component of care for these patients. There is a paucity of studies in the setting of paramedic-identified STEMI. This study investigated mortality and factors associated with mortality in a large state-wide prehospital STEMI sample. Methods: Included were adult STEMI patients identified and treated with reperfusion therapy by paramedics in the field between January 2016 and December 2018 in Queensland, Australia. 30-day and one-year all-cause mortality was compared between two prehospital reperfusion pathways: prehospital fibrinolysis versus direct referral to a hospital for primary percutaneous coronary intervention (direct percutaneous coronary intervention [PCI] referral). For prehospital fibrinolysis patients, factors associated with failed fibrinolysis were investigated. For direct PCI referral patients, factors associated with mortality were examined. Results: The 30-day mortality was 2.2% for prehospital fibrinolysis group and 1.8% for direct PCI referral group (p = 0.661). One-year mortality for the two groups was 2.7% and 3.2%, respectively (p = 0.732). Failed prehospital fibrinolysis was observed in 20.1% of patients receiving this therapy, with male gender and history of heart failure being predictors. For direct PCI referral group, low left ventricular ejection fraction (LVEF) on admission and cardiogenic shock prior to PCI were predictors of both 30-day and one-year mortality. Aboriginal and Torres Strait Islander status, and impaired kidney function on admission, were associated with one-year but not 30-day mortality. Being overweight was associated with lower 30-day mortality. Conclusions: Mortality in STEMI patients identified and treated by paramedics was low, and the prehospital fibrinolysis treatment pathway was effective with a mortality rate comparable to that of patients undergoing primary PCI. Key words: prehospital; Queensland; cardiac reperfusion; STEMI.

Evidence in Guidelines for Treatment of Coronary Artery Disease

In this chapter, we focus on evidences in current guidelines for treatment of coronary artery disease (CAD). In Part 1, diet and lifestyle management is discussed, which plays an important role in CAD risk control, including forming healthy dietary pattern, maintaining proper body weight, physical exercise, smoking cessation, and so on. Part 2 elaborated on revascularization strategies and medical treatments in patients presenting with acute coronary syndrome (ACS), including specific AHA and ESC guidelines on ST elevation myocardial infarction (STEMI) and non-ST elevation ACS (NSTE-ACS). Part 3 discussed chronic stable coronary artery disease (SCAD), the treatment objective of which is a combination of both symptomatic and prognostic improvement. Yet many of the recommendations for SCAD are expert-based rather than evidence-based. Initial medical treatment is safe and beneficial for most patients. While cumulating studies have focused on optimizing pharmacological therapy (referring to nitrates, beta-blockers, calcium channel blockers, antiplatelet agents, ACEI/ARB, statins, etc.), education, habitual modification, and social support matters a lot for reducing cardiac morbidity and mortality. Patients with moderate-to-severe symptoms and complex lesions should be considered for revascularization. But practical management of revascularization shall take individual characteristics, preference, and compliance into consideration as well.