Timing of coronary angiography in survivors of out-of-hospital cardiac arrest without obvious extracardiac causes

Performance of ECG-Derived Digital Biomarker for Screening Coronary Occlusion in Resuscitated Out-of-Hospital Cardiac Arrest Patients: A Comparative Study between Artificial Intelligence and a Group of Experts

Acute coronary syndrome is a significant part of cardiac etiology contributing to out-of-hospital cardiac arrest (OHCA), and immediate coronary angiography has been proposed to improve survival. This study evaluated the effectiveness of an AI algorithm in diagnosing near-total or total occlusion of coronary arteries in OHCA patients who regained spontaneous circulation. Conducted from 1 July 2019 to 30 June 2022 at a tertiary university hospital emergency department, it involved 82 OHCA patients, with 58 qualifying after exclusions. The AI used was the Quantitative ECG (QCG™) system, which provides a STEMI diagnostic score ranging from 0 to 100. The QCG score's diagnostic performance was compared to assessments by two emergency physicians and three cardiologists. Among the patients, coronary occlusion was identified in 24. The QCG score showed a significant difference between occlusion and non-occlusion groups, with the former scoring higher. The QCG biomarker had an area under the curve (AUC) of 0.770, outperforming the expert group's AUC of 0.676. It demonstrated 70.8% sensitivity and 79.4% specificity. These findings suggest that the AI-based ECG biomarker could predict coronary occlusion in resuscitated OHCA patients, and it was non-inferior to the consensus of the expert group.

Early coronary angioplasty fails to lower all-cause mortality in patients with out-of-hospital cardiac arrest without ST-segment elevation: A systematic review and meta-analysis

Introduction

Out-of-hospital cardiac arrest (OHCA) is defined as the loss of functional mechanical activity of the heart in association with an absence of systemic circulation, occurring outside of a hospital. Immediate coronary angiography (CAG) with percutaneous coronary intervention is recommended for OHCA with ST-elevation. We aimed to evaluate the effect of early CAG on mortality and neurological outcomes in OHCA patients without ST-elevation.

Methods

This meta-analysis and systemic review was conducted as per principles of Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA) group. A protocol was registered with the International Prospective Register of Systematic Reviews (PROSPERO, Ref No. = CRD42022327833). A total of 674 studies were retrieved after scanning several databases (PubMed Central, EMBASE, Medline, and Cochrane Central Register of Controlled Trials).

Results

A total of 18 studies were selected for the final analysis, including 6 randomized control trials and 12 observational studies. Statistically, there was no significant difference in primary outcome, i.e., mortality, between early and delayed CAG. In terms of the grade of neurological recovery as a secondary outcome, early and delayed CAG groups also showed no statistically significant difference.

Conclusion

Early CAG has no survival benefits in patients with no ST elevations on ECG after OHCA.

Coronary angiography after cardiac arrest without ST-elevation myocardial infarction: a network meta-analysis

AIMS

This network meta-analysis aimed to assess the effect of early coronary angiography (CAG) compared with selective CAG (late and no CAG) for patients after out-of-hospital cardiac arrest without ST-elevation myocardial infarction (NSTE-OHCA).

METHODS AND RESULTS

A systematic literature search was performed using the EMBASE, MEDLINE and Web of Science databases without restrictions on publication date. The last search was performed on 15 July 2022. Randomized controlled trials (RCTs) and non-randomized studies (NRS) comparing the effect of early CAG to selective CAG after NSTE-OHCA on survival and/or neurological outcomes were included. Meta-analyses were performed based on a DerSimonian-Laird random effects model. A total of 18 studies were identified by the literature search. After the exclusion of two studies due to high risk of bias, 16 studies (six RCTs, ten NRS) were included in the final analyses. Meta-analyses showed a statistically significant increase in survival after early CAG compared with selective CAG in the overall analysis [OR: 1.40, 95% confidence interval (CI): (1.12-1.76), P < 0.01, I2 = 68%]. This effect was lost in the subgroup analysis of RCTs [OR: 0.89, 95% CI: (0.73-1.10), P = 0.29, I2 = 0%]. Random effects model network meta-analysis of NRS based on a Bayesian method showed statistically significant increased survival after late compared with early CAG [OR: 4.20, 95% CI: (1.22, 20.91)].

CONCLUSION

The previously reported superiority of early CAG after NSTE-OHCA is based on NRS at high risk of selection and survivorship bias. The meta-analysis of RCTs does not support routinely performing early CAG after NSTE-OHCA.

Timing and Outcomes After Coronary Angiography Following Out-of-Hospital Cardiac Arrest Without Signs of ST-Segment Elevation Myocardial Infarction

BACKGROUND

There is broad consensus that resuscitated out-of-hospital cardiac arrest (OHCA) patients with ST-segment elevation myocardial infarction (STEMI) should receive immediate coronary angiography (CAG); however, factors that guide patient selection and optimal timing of CAG for post-arrest patients without evidence of STEMI remain incompletely described.

OBJECTIVE

We sought to describe the timing of post-arrest CAG in actual practice, patient characteristics associated with decision to perform immediate vs. delayed CAG, and patient outcomes after CAG.

METHODS

We conducted a retrospective cohort study at seven U.S. academic hospitals. Resuscitated adult patients with OHCA were included if they presented between January 1, 2015 and December 31, 2019 and received CAG during hospitalization. Emergency medical services run sheets and hospital records were analyzed. Patients without evidence of STEMI were grouped and compared based on time from arrival to CAG performance into "early" (≤ 6 h) and "delayed" (> 6 h).

RESULTS

Two hundred twenty-one patients were included. Median time to CAG was 18.6 h (interquartile range [IQR] 1.5-94.6 h). Early catheterization was performed on 94 patients (42.5%) and delayed catheterization was performed on 127 patients (57.5%). Patients in the early group were older (61 years [IQR 55-70 years] vs. 57 years [IQR 47-65] years) and more likely to be male (79.8% vs. 59.8%). Those in the early group were more likely to have clinically significant lesions (58.5% vs. 39.4%) and receive revascularization (41.5% vs. 19.7%). Patients were more likely to die in the early group (47.9% vs. 33.1%). Among survivors, there was no significant difference in neurologic recovery at discharge.

CONCLUSIONS

OHCA patients without evidence of STEMI who received early CAG were older and more likely to be male. This group was more likely to have intervenable lesions and receive revascularization.

Modeling current practices in critical care comparative effectiveness research

Objective: To determine whether contemporaneous practices are adequately represented in recent critical care comparative effectiveness research studies. Design: All critical care comparative effectiveness research trials published in the New England Journal of Medicine from April 2019 to March 2020 were identified. To examine studies published in other high impact medical journals during the same period, such trials were subsequently also identified in the Journal of the American Medical Association and The Lancet. All cited sources were reviewed, and the medical literature was searched to find studies describing contemporary practices. Then, the designated control group or the comparable therapies studied were examined to determine if they represented contemporaneous critical care practices as described in the medical literature. Results: Twenty-five of 332 randomised clinical trials published in these three journals during this 1-year period described critical care comparative effectiveness research that met our inclusion criteria. Seventeen characterised current practices before enrolment (using surveys, observational studies and guidelines) and then incorporated current practices into one or more study arm. In the other eight, usual care arms appeared insufficient. Four of these trials randomly assigned patients to one of two fixed approaches at either end of a range of usually titrated care. However, due to randomisation, different subgroups within each arm received care that was inappropriate for their specific clinical conditions. In the other four of these trials, common practices influencing treatment choice were not reflected in the trial design, despite a prior effort to characterise usual care. Conclusion: One-third of critical care comparative effectiveness research trials published in widely read medical journals during a recent year did not include a designated control arm or comparable therapies representative of contemporary practices. Failure to incorporate contemporary practices into critical care comparative effectiveness trials appears to be a widespread design weakness.

Impact of emergent coronary angiography after out-of-the-hospital cardiac arrest without ST-segment elevation - a systematic review and meta-analysis

INTRODUCTION

Coronary artery disease is a leading cause of out-of-the-hospital cardiac arrest (OHCA). However, there is no consensus on whether OHCA patients without ST-segment elevation (STE) benefit from emergent (ie < 2 h) coronary angiography (CAG). Our aim was to assess the impact of emergent CAG in no-STE OHCA patients.

METHODS

We performed a systematic review and meta-analysis by searching the MEDLINE, Cochrane, Scopus, CINAHL and JBI databases for randomized controlled trials (RCTs) comparing emergent CAG versus standard of care (ie CAG >2 h after OHCA or not performed) in no-STE OHCA patients of presumed cardiac aetiology. The primary outcome was short term survival. Secondary outcomes included survival with good neurological outcome, mid-term survival, left ventricle ejection fraction (LVEF), acute kidney injury (AKI) and renal replacement therapy (RRT), ventricular arrhythmias and major bleeding during hospital stay.

RESULTS

Seven RCTs met the inclusion and exclusion criteria and were included; one was included only in the analysis of mid-term survival and another in the LVEF analysis. Five studies (1278 patients, 643 with early CAG and 635 with no early CAG) were included in the analysis of the primary endpoint. The groups were balanced for all baseline characteristics but previous PCI, which was more frequent in the standard of care groups. There were no significant differences between groups for short-term survival (57 vs 61%; OR0.85, 95% CI0.68-1.07; I² = 0%). There were also no differences for any of the secondary endpoints.

CONCLUSION

Routine emergent CAG did not improve survival in comatose survivors of OHCA with shockable rhythm and no-STE.

Clinical factors associated with significant coronary lesions following out-of-hospital cardiac arrest

OBJECTIVES

Out-of-hospital cardiac arrest (OHCA) afflicts >350,000 people annually in the United States. While postarrest coronary angiography (CAG) with percutaneous coronary intervention (PCI) has been associated with improved survival in observational cohorts, substantial uncertainty exists regarding patient selection for postarrest CAG. We tested the hypothesis that symptoms consistent with acute coronary syndrome (ACS), including chest discomfort, prior to OHCAs are associated with significant coronary lesions identified on postarrest CAG.

METHODS

We conducted a multicenter retrospective cohort study among eight regional hospitals. Adult patients who experienced atraumatic OHCA with successful initial resuscitation and subsequent CAG between January 2015 and December 2019 were included. We collected data on prehospital documentation of potential ACS symptoms prior to OHCA as well as clinical factors readily available during postarrest care. The primary outcome in multivariable regression modeling was the presence of significant coronary lesions (defined as >50% stenosis of left main or >75% stenosis of other coronary arteries).

RESULTS

Four-hundred patients were included. Median (interquartile range) age was 59 (51-69) years; 31% were female. At least one significant stenosis was found in 62%, of whom 71% received PCI. Clinical factors independently associated with a significant lesion included a history of myocardial infarction (adjusted odds ratio [aOR] = 6.5, [95% confidence interval {CI} = 1.3 to 32.4], p = 0.02), prearrest chest discomfort (aOR = 4.8 [95% CI = 2.1 to 11.8], p ≤ 0.001), ST-segment elevations (aOR = 3.2 [95% CI = 1.7 to 6.3], p < 0.001), and an initial shockable rhythm (aOR = 1.9 [95% CI = 1.0 to 3.4], p = 0.05).

CONCLUSIONS

Among survivors of OHCA receiving CAG, history of prearrest chest discomfort was significantly and independently associated with significant coronary artery lesions on postarrest CAG. This suggests that we may be able to use prearrest symptoms to better risk stratify patients following OHCA to decide who will benefit from invasive angiography.

Coronary Angiography in Patients With Out-of-Hospital Cardiac Arrest Without ST-Segment Elevation: A Systematic Review and Meta-Analysis

OBJECTIVES

The authors conducted a meta-analysis to study clinical outcomes in patients who underwent early versus nonearly coronary angiography (CAG) in the setting of out-of-hospital cardiac arrest (OHCA) without ST-segment elevation.

BACKGROUND

The benefit of performing early CAG in patients with OHCA without STE remains disputed.

METHODS

MEDLINE, Embase, and the Cochrane Central Register of Controlled Trials were searched according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines from inception until February 21, 2020. Early and nonearly CAG patients were identified on the basis of the definitions mentioned in respective published studies. The primary outcome studied was 30-day mortality. Secondary outcomes were neurological status and the rate of percutaneous coronary intervention (PCI) following cardiac arrest.

RESULTS

Of 4,516 references, 11 studies enrolling 3,581 patients were included in the final meta-analysis. Random-effects analysis showed no differences in 30-day mortality (risk ratio [RR]: 0.86; 95% confidence interval [CI]: 0.71 to 1.04; p = 0.12; I² = 74%), neurological status (RR: 1.08; 95% CI: 0.94 to 1.24; p = 0.28; I² = 69%), and rate of PCI (RR: 1.22; 95% CI: 0.94 to 1.59; p = 0.13; I² = 67%) between the 2 groups. Diabetes mellitus, chronic renal failure, previous PCI, and lactate level were found to be significant predictors of 30-day mortality on meta-regression (p < 0.05).

CONCLUSIONS

This analysis shows that there is no significant difference in 30-day mortality, neurological status, or rate of PCI among patients with OHCA without STE treated with early versus nonearly CAG. Thirty-day mortality is determined by presentation comorbidities rather than revascularization.

Which Out-of-Hospital Cardiac Arrest Patients without ST-Segment Elevation Benefit from Early Coronary Angiography? Results from the Korean Hypothermia Network Prospective Registry

The effect of early coronary angiography (CAG) in out-of-hospital cardiac arrest (OHCA) patients without ST-elevation (STE) is still controversial. It is not known which subgroups of patients without STE are the most likely to benefit. The objective of this study was to evaluate the association between emergency CAG and neurologic outcomes and identify subgroups with improved outcomes when emergency CAG was performed. This prospective, multicenter, observational cohort study was based on data from the Korean Hypothermia Network prospective registry (KORHN-PRO) 1.0. Adult OHCA patients who were treated with targeted temperature management (TTM) without any obvious extracardiac cause were included. Patients were dichotomized into early CAG (≤24 h) and no early CAG (>24 h or not performed) groups. High-risk patients were defined as having the Global Registry of Acute Coronary Events (GRACE) score > 140, time from collapse to return of spontaneous circulation (ROSC) > 30 min, lactate level > 7.0 mmol/L, arterial pH < 7.2, cardiac enzyme elevation and ST deviation. The primary outcome was good neurologic outcome at 6 months after OHCA. Of the 1373 patients from the KORHN-PRO 1.0 database, 678 patients met the inclusion criteria. The early CAG group showed better neurologic outcomes at 6 months after cardiac arrest (CA) (adjusted odds ratio: 2.21 (1.27-3.87), p = 0.005). This was maintained even after propensity score matching (adjusted odds ratio: 2.23 (1.39-3.58), p < 0.001). In the subgroup analysis, high-risk patients showed a greater benefit from early CAG. In contrast, no significant association was found in low-risk patients. Early CAG was associated with good neurologic outcome at 6 months after CA and should be considered in high-risk patients.

The role of coronary angiography in out-of-hospital cardiac arrest patients in the absence of ST-segment elevation: A literature review

Out-of-hospital cardiac arrest (OHCA) is a major cause of death. Although the aetiology of cardiac arrest can be diverse, the most common cause is ischaemic heart disease. Coronary angiography and percutaneous coronary intervention, if indicated, has been associated with improved long-term survival for patients with initial shockable rhythm. However, in patients without ST-segment elevation on the post-resuscitation electrocardiogram, the optimal timing of performing this invasive procedure is uncertain. One important challenge that clinicians face is to appropriately select patients that will benefit from immediate coronary angiography, yet avoid unnecessary delay of intensive care support and targeted temperature management. Observational studies have reported contradictory results and until recently, randomised trials were lacking. The Coronary Angiography after Cardiac Arrest without ST-segment elevation (COACT) was the first randomised trial that provided comparative information between coronary angiography treatment strategies. This literature review will provide the current knowledge and gaps in the literature regarding optimal care for patients successfully resuscitated from OHCA in the absence of ST-segment elevation and will primarily focus on the role and timing of coronary angiography in this high-risk patient population.

Utility and Challenges of an Early Invasive Strategy in Patients Resuscitated From Out-of-Hospital Cardiac Arrest

Out-of-hospital cardiac arrest (OHCA) is frequently triggered by acute myocardial ischemia. Coronary angiography is an important component of post-resuscitation care for patients with OHCA without an evident noncardiac cause, to identify underlying coronary artery disease and allow revascularization. Most patients undergoing coronary angiography after OHCA have obstructive coronary artery disease, and nearly one-half of patients have acute coronary occlusion. Early coronary angiography and percutaneous coronary intervention after OHCA have been associated with improved survival in observational studies, but these studies demonstrate selection bias, and randomized trials are lacking. Selection of patients for coronary angiography after OHCA can be challenging, particularly in comatose patients whose outcomes are driven primarily by anoxic brain injury. As for other patients with acute coronary syndromes, patients with ST-segment elevation after OHCA have a high probability of acute coronary occlusion warranting emergent coronary angiography. Patients with cardiogenic shock after OHCA are a high-risk population also requiring emergent coronary angiography. Among patients in stable condition after OHCA without ST-segment elevation, other clinical predictors can be used to identify those needing early coronary angiography to identify obstructive coronary artery disease. Despite the challenges with early neurological prognostication in comatose patients with OHCA, those with multiple objective markers of poor prognosis appear less likely to benefit from revascularization, and early coronary angiography may be reasonably deferred in appropriately selected patients meeting these criteria. The authors propose an algorithm to guide patient selection for coronary angiography after OHCA that combines clinical predictors of acute coronary occlusion and early clinical predictors of severe brain injury.

Post resuscitation electrocardiogram for coronary angiography indication after out-of-hospital cardiac arrest

BACKGROUND

Coronary angiography is the standard of care after Out-of-Hospital Cardiac Arrest (OHCA), but its benefit for patients without persistent ST-segment elevation (STE) remains controversial.

METHODS

All patients admitted for coronary angiography after a resuscitated OHCA were consecutively included in this prospective study. Three patient groups were defined according to post-resuscitation ECG: STE or new left bundle branch block (LBBB) (group 1); other ST/T repolarization disorders (group 2) and no repolarisation disorders (group 3). The proportion and predictive factors of an acute coronary lesion, defined by acute coronary occlusion or thrombotic lesion or lesion associated with flow impairment, were evaluated according to different groups as well as thirty-day mortality.

RESULTS

Among 129 consecutive patients: 62 (48.1%), 30 (23.3%) and 30 (23.3%) patients were included in groups 1, 2 and 3 respectively. An acute coronary lesion was observed in 43% (n = 55) of patients, mainly in group 1 (n = 44, 70.9%). Initial coronary TIMI 0/1 flow was more frequently observed in group 1 than in group 2 (n = 25, 40.3% vs n = 1, 3.3%) and never in group 3. Chest pain and STE or new LBBB were independently associated with an acute coronary lesion (adj. OR = 7.14 [1.85-25.00]; p = 0.004 and adj. OR = 11.10 [3.70-33.33]; p < 0.001 respectively). In absence of any repolarization disorders, acute coronary lesion or occlusion were excluded with negative predictive values of 93.3% and 100% respectively. The one-month survival rate was 38.8% and was better in patients among the group 1 compared to those from the 2 other groups (n = 28, 45.2% vs n = 21, 35%, respectively; p = 0.014).

CONCLUSION

Considering the high negative predictive value of post-resuscitation ECG to exclude acute coronary lesion and occlusion after OHCA, a delayed coronary angiography appears a reliable alternative for patients without repolarization disorders.

Contemporary Management of Out-of-hospital Cardiac Arrest in the Cardiac Catheterisation Laboratory: Current Status and Future Directions

Out-of-hospital cardiac arrest (OHCA) is an important cause of mortality and morbidity in developed countries and remains an important public health burden. A primary cardiac aetiology is common in OHCA patients, and so patients are increasingly brought to specialist cardiac centres for consideration of coronary angiography, percutaneous coronary intervention and mechanical circulatory support. This article focuses on the management of OHCA in the cardiac catheterisation laboratory. In particular, it addresses conveyance of the OHCA patient direct to a specialist centre, the role of targeted temperature management, pharmacological considerations, provision of early coronary angiography and mechanical circulatory support.

Clinical Implication of Coronary Artery Calcium Score in Survivors of Out-of-Hospital Cardiac Arrest

Background: The aim of this study was to evaluate the clinical ability of coronary artery calcium (CAC) score to identify acute myocardial infarction (AMI) in survivors of out-of-hospital cardiac arrest (OHCA).

Methods and Results: We studied 180 consecutive survivors of OHCA who underwent immediate non-contrast computed tomography (CT) and coronary angiography. Seventy-one patients had ST elevation or left bundle branch block (LBBB; group 1) and 109 patients did not have ST elevation or LBBB (group 2) on post-resuscitation electrocardiogram (ECG). CAC score was significantly higher in AMI compared with non-AMI in groups 1 and 2. The optimal cut-off of CAC score to identify AMI was 11.5 (sensitivity, 80%; specificity, 71%) in group 1, and 27.4 (sensitivity, 80%; specificity, 76%) in group 2. On multivariate analysis, CAC score was the strongest predictive marker of AMI (OR, 10.91; 95% CI: 6.00–25.97). In addition, CAC score was an independent predictor of 30-day survival (OR, 0.38; 95% CI: 0.15–0.95).

Conclusions: Evaluation of CAC is a useful method to identify AMI in survivors of OHCA, regardless of ST changes on post-resuscitation ECG.

Clinical Factors Associated with Obstructive Coronary Artery Disease in Patients with Out-of-Hospital Cardiac Arrest: Data from the Korean Cardiac Arrest Research Consortium (KoCARC) Registry

BACKGROUND

Although coronary artery disease (CAD) is a major cause of out-of-hospital cardiac arrest (OHCA), there has been no convinced data on the necessity of routine invasive coronary angiography (ICA) in OHCA. We investigated clinical factors associated with obstructive CAD in OHCA.

METHODS

Data from 516 OHCA patients (mean age 58 years, 83% men) who underwent ICA after resuscitation was obtained from a nation-wide OHCA registry. Obstructive CAD was defined as the lesions with diameter stenosis ≥ 50% on ICA. Independent clinical predictors for obstructive CAD were evaluated using multiple logistic regression analysis, and their prediction performance was compared using area under the receiver operating characteristic curve with 10,000 repeated random permutations.

RESULTS

Among study patients, 254 (49%) had obstructive CAD. Those with obstructive CAD were older (61 vs. 55 years, P < 0.001) and had higher prevalence of hypertension (54% vs. 36%, P < 0.001), diabetes mellitus (29% vs. 21%, P = 0.032), positive cardiac enzyme (84% vs. 74%, P = 0.010) and initial shockable rhythm (70% vs. 61%, P = 0.033). In multiple logistic regression analysis, old age (≥ 60 years) (odds ratio [OR], 2.01; 95% confidence interval [CI], 1.36-3.00; P = 0.001), hypertension (OR, 1.74; 95% CI, 1.18-2.57; P = 0.005), positive cardiac enzyme (OR, 1.72; 95% CI, 1.09-2.70; P = 0.019), and initial shockable rhythm (OR, 1.71; 95% CI, 1.16-2.54; P = 0.007) were associated with obstructive CAD. Prediction ability for obstructive CAD increased proportionally when these 4 factors were sequentially combined (P < 0.001).

CONCLUSION

In patients with OHCA, those with old age, hypertension, positive cardiac enzyme and initial shockable rhythm were associated with obstructive CAD. Early ICA should be considered in these patients.

Coronary Angiography after Cardiac Arrest without ST-Segment Elevation

BACKGROUND

Ischemic heart disease is a major cause of out-of-hospital cardiac arrest. The role of immediate coronary angiography and percutaneous coronary intervention (PCI) in the treatment of patients who have been successfully resuscitated after cardiac arrest in the absence of ST-segment elevation myocardial infarction (STEMI) remains uncertain.

METHODS

In this multicenter trial, we randomly assigned 552 patients who had cardiac arrest without signs of STEMI to undergo immediate coronary angiography or coronary angiography that was delayed until after neurologic recovery. All patients underwent PCI if indicated. The primary end point was survival at 90 days. Secondary end points included survival at 90 days with good cerebral performance or mild or moderate disability, myocardial injury, duration of catecholamine support, markers of shock, recurrence of ventricular tachycardia, duration of mechanical ventilation, major bleeding, occurrence of acute kidney injury, need for renal-replacement therapy, time to target temperature, and neurologic status at discharge from the intensive care unit.

RESULTS

At 90 days, 176 of 273 patients (64.5%) in the immediate angiography group and 178 of 265 patients (67.2%) in the delayed angiography group were alive (odds ratio, 0.89; 95% confidence interval [CI], 0.62 to 1.27; P = 0.51). The median time to target temperature was 5.4 hours in the immediate angiography group and 4.7 hours in the delayed angiography group (ratio of geometric means, 1.19; 95% CI, 1.04 to 1.36). No significant differences between the groups were found in the remaining secondary end points.

CONCLUSIONS

Among patients who had been successfully resuscitated after out-of-hospital cardiac arrest and had no signs of STEMI, a strategy of immediate angiography was not found to be better than a strategy of delayed angiography with respect to overall survival at 90 days. (Funded by the Netherlands Heart Institute and others; COACT Netherlands Trial Register number, NTR4973.).

Lactate, lactate clearance and outcome after cardiac arrest: A post-hoc analysis of the TTM-Trial

BACKGROUND

Admission lactate and lactate clearance are implemented for risk stratification in sepsis and trauma. In out-of-hospital cardiac arrest, results regarding outcome and lactate are conflicting.

METHODS

This is a post-hoc analysis of the Target Temperature Management trial in which 950 unconscious patents after out-of-hospital cardiac arrest were randomized to a temperature intervention of 33°C or 36°C. Serial lactate samples during the first 36 hours were collected. Admission lactate, 12-hour lactate, and the clearance of lactate within 12 hours after admission were analyzed and the association with 30-day mortality assessed.

RESULTS

Samples from 877 patients were analyzed. In univariate logistic regression analysis, the odds ratio for death by day 30 for each mmol/L was 1.12 (1.08-1.16) for admission lactate, P < .01, 1.21 (1.12-1.31) for 12-hour lactate, P < .01, and 1.003 (1.00-1.01) for each percentage point increase in 12-hour lactate clearance, P = .03. Only admission lactate and 12-hour lactate levels remained significant after adjusting for known predictors of outcome. The area under the receiver operating characteristic curve was 0.65 (0.61-0.69), P < .001, 0.61 (0.57-0.65), P < .001, and 0.53 (0.49-0.57), P = .15 for admission lactate, 12-hour lactate, and 12-hour lactate clearance, respectively.

CONCLUSIONS

Admission lactate and 12-hour lactate values were independently associated with 30-day mortality after out-of-hospital cardiac arrest while 12-hour lactate clearance was not. The clinical value of lactate as the sole predictor of outcome after out-of-hospital cardiac arrest is, however, limited.