Balancing thrombosis and bleeding after out-of-hospital cardiac arrest related to acute coronary syndrome: A literature review

Clinical and angiographic characteristics of out-of-hospital cardiac arrest among patients with ST-segment elevation myocardial infarction

BACKGROUND

Out-of-hospital cardiac arrest (OHCA) is the most severe complication of ST-segment elevation myocardial infarction (STEMI). Nevertheless, clinical and angiographic characteristics associated with OHCA among patients with STEMI have not been studied extensively.

AIM

To evaluate the clinical and angiographic characteristics of consecutive patients who presented with STEMI associated or not with OHCA.

METHODS

This was an observational study including consecutive patients treated for STEMI associated or not with OHCA. Baseline clinical and angiographic characteristics, biological characteristics and mortality were compared between patients with STEMI who experienced OHCA and patients with STEMI who did not.

RESULTS

Among the 686 included patients with STEMI, 148 (21.6%) presented with concomitant OHCA. Multivariable analysis revealed that culprit lesion localized on the left system (odds ratio [OR] 1.94, 95% confidence interval [CI] 1.24-3.13; P<0.01), culprit lesion at the level of a bifurcation lesion (OR 1.87, 95% CI 1.21-2.88; P<0.01) and the presence of chronic total occlusion on another artery (OR 3.39, 95% CI 1.93-5.99; P<0.001) were associated with the occurrence of OHCA, whereas dyslipidaemia, familial history of coronary artery disease and hypertension were found to be negatively associated with the occurrence of OHCA in patients with STEMI: OR 0.47, 95% CI 0.29-0.75 (P<0.01); OR 0.09, 95% CI 0.02-0.25 (P<0.001); and OR 0.60, 95% CI 0.38-0.93 (P=0.02), respectively.

CONCLUSION

In this study of consecutive patients with STEMI, culprit lesion localized on the left system, culprit lesion at the level of a bifurcation lesion and the presence of chronic total occlusion on a non-culprit artery were associated with OHCA.

Outcome of Out-of-Hospital Cardiac Arrest Patients Stratified by Pre-Clinical Loading with Aspirin and Heparin: A Retrospective Cohort Analysis

Background: Out-of-hospital cardiac arrest (OHCA) has a high prevalence of obstructive coronary artery disease and total coronary occlusion. Consequently, these patients are frequently loaded with antiplatelets and anticoagulants before hospital arrival. However, OHCA patients have multiple non-cardiac causes and high susceptibility for bleeding. In brief, there is a gap in the evidence for loading in OHCA patients. Objective: The current analysis stratified the outcome of patients with OHCA according to pre-clinical loading. Material and Methods: In a retrospective analysis of an all-comer OHCA registry, patients were stratified by loading with aspirin (ASA) and unfractionated heparin (UFH). Bleeding rate, survival to hospital discharge and favorable neurological outcomes were measured. Results: Overall, 272 patients were included, of whom 142 were loaded. Acute coronary syndrome was diagnosed in 103 patients. One-third of STEMIs were not loaded. Conversely, 54% with OHCA from non-ischemic causes were pretreated. Loading was associated with increased survival to hospital discharge (56.3 vs. 40.3%, p = 0.008) and a more favorable neurological outcome (80.7 vs. 62.6% p = 0.003). Prevalence of bleeding was comparable (26.8 vs. 31.5%, p = 0.740). Conclusions: Pre-clinical loading did not increase bleeding rates and was associated with favorable survival. Overtreatment of OHCA with non-ischemic origin, but also undertreatment of STEMI-OHCA were documented. Loading without definite diagnosis of sustained ischemia is debatable in the absence of reliable randomized controlled data.

Intracoronary imaging in addition to coronary angiography for patients with out-of-hospital cardiac arrest: More information for better care?

About 70% of out-of-hospital cardiac arrests are related to an ischaemic heart disease in Western countries. Percutaneous coronary intervention has been shown to improve the prognosis of survivors when an unstable coronary lesion is identified as the potential cause of the cardiac arrest. Acute complete coronary occlusion is often demonstrated among patients with ST-segment elevation on electrocardiogram after the return of spontaneous circulation. In patients without ST-segment elevation, routine coronary angiography has been shown to be not superior to conservative management. However, an electrocardiogram-based decision to perform immediate coronary angiography could be insufficient to identify unstable coronary lesions, which are frequently associated with intermediate coronary stenosis. Intracoronary imaging can be helpful to detect plaque rupture or erosion and intracoronary thrombus, but could also lead to better stent implantation, and help to reduce the risk of stent thrombosis. In patients with coronary lesions without the instability characteristic, conservative management should be the default strategy, and a search for another cause of the cardiac arrest should be systematic. In the present review, we sought to describe the potential benefit of intracoronary imaging in patients with out-of-hospital cardiac arrest.

Role of adjunct anticoagulant or thrombolytic therapy in cardiac arrest without ST-segment-elevation or percutaneous coronary intervention: A systematic review and meta-analysis

This study sought to compare the impact of additional anticoagulation or thrombolytic therapy in patients with cardiac arrest without ST-segment-elevation on electrocardiography and not receiving percutaneous coronary intervention. Three studies (two randomized controlled studies and one observational study) were included, which demonstrated that use of anticoagulation or thrombolytic therapy was associated with higher risk of bleeding, without improvements in time to return of spontaneous circulation or in-hospital mortality.