Canadian Cardiovascular Society/Canadian Cardiovascular Critical Care Society/Canadian Association of Interventional Cardiology Clinical Practice Update on Optimal Post Cardiac Arrest and Refractory Cardiac Arrest Patient Care.

Survival to hospital discharge among patients with out-of-hospital cardiac arrest (OHCA) is low and important regional differences in treatment practices and survival have been described. Since the 2017 publication of the Canadian Cardiovascular Society's position statement on OHCA care, multiple randomized controlled trials have helped to better define optimal post cardiac arrest care. This working group provides updated guidance on the timing of cardiac catheterization in patients with ST-elevation and without ST-segment elevation, on a revised temperature control strategy targeting normothermia instead of hypothermia, blood pressure, oxygenation, and ventilation parameters, and on the treatment of rhythmic and periodic electroencephalography patterns in patients with a resuscitated OHCA. In addition, prehospital trials have helped craft new expert opinions on antiarrhythmic strategies (amiodarone or lidocaine) and outline the potential role for double sequential defibrillation in patients with refractory cardiac arrest when equipment and training is available. Finally, we advocate for regionalized OHCA care systems with admissions to a hospital capable of integrating their post OHCA care with comprehensive on-site cardiovascular services and provide guidance on the potential role of extracorporeal cardiopulmonary resuscitation in patients with refractory cardiac arrest. We believe that knowledge translation through national harmonization and adoption of contemporary best practices has the potential to improve survival and functional outcomes in the OHCA population.

The Evolving Role of Electroencephalography in Postarrest Care.

Electroencephalography is an accessible, portable, noninvasive and safe means of evaluating a patient's brain activity. It can aid in diagnosis and management decisions for post-cardiac arrest patients with seizures, myoclonus and other non-epileptic movements. It also plays an important role in a multimodal approach to neuroprognostication predicting both poor and favorable outcomes. Individuals ordering, performing and interpreting these tests, regardless of the indication, should understand the supporting evidence, logistical considerations, limitations and impact the results may have on postarrest patients and their families as outlined herein.

The Clinical Validation of a Common Analytical Change Criteria for Cardiac Troponin for Ruling in an Acute Cardiovascular Outcome in Patients Presenting with Ischemic Chest Pain Symptoms.

Serial cardiac troponin (cTn) testing on patients with symptoms suggestive of acute coronary syndrome (ACS) is primarily to identify those patients with evolving myocardial injury. With the improved analytical performance of the high-sensitivity cTn (hs-cTn) assays, different change criteria have been proposed that are mostly assay dependent. Here, we developed and compared a new Common Change Criteria (3C for the combined criteria of >3 ng/L, >30%, or >15% based on the initial cTn concentration of <10 ng/L, 10 to 100 ng/L, or >100 ng/L, respectively) method, versus the 2 h assay-dependent absolute change criteria endorsed by the European Society of Cardiology (ESC), versus the common relative >20% change criterion. These different analytical change criteria were evaluated in 855 emergency department (ED) patients with symptoms of ACS and who had two samples collected 3 h apart. The cTn concentrations were measured with four different assays (Abbott hs-cTnI, Roche hs-cTnT, Ortho cTnI-ES, and Ortho hs-cTnI). The outcomes evaluated were myocardial infarction (MI) and a composite outcome (MI, unstable angina, ventricular arrhythmia, heart failure, or cardiovascular death) within 7 days of ED presentation. The combined change criteria (3C) method yielded higher specificities (range: 93.9 to 97.2%) as compared to the >20% criterion (range: 42.3 to 88.1%) for all four assays for MI. The 3C method only yielded a higher specificity estimate for MI for the cTnI-ES assay (95.9%) versus the absolute change criteria (71.7%). Similar estimates were obtained for the composite outcome. There was also substantial agreement between hs-cTnT and the different cTnI assays for MI with the 3C method, with the percent agreement being ≥95%. The Common Change Criteria (3C) method combining both absolute and different percent changes may be used with cTnI, hs-cTnT, and different hs-cTnI assays to yield similar high-specificity (rule-in) estimates for adverse cardiovascular events for patients presenting to the ED with ACS symptoms.

Neuroprognostication in the Post Cardiac Arrest Patient: A Canadian Cardiovascular Society Position Statement.

Cardiac arrest (CA) is associated with a low rate of survival with favourable neurologic recovery. The most common mechanism of death after successful resuscitation from CA is withdrawal of life-sustaining measures on the basis of perceived poor neurologic prognosis due to underlying hypoxic-ischemic brain injury. Neuroprognostication is an important component of the care pathway for CA patients admitted to hospital but is complex, challenging, and often guided by limited evidence. Using the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) system to evaluate the evidence underlying factors or diagnostic modalities available to determine prognosis, recommendations were generated in the following domains: (1) circumstances immediately after CA; (2) focused neurologic exam; (3) myoclonus and seizures; (4) serum biomarkers; (5) neuroimaging; (6) neurophysiologic testing; and (7) multimodal neuroprognostication. This position statement aims to serve as a practical guide to enhance in-hospital care of CA patients and emphasizes the adoption of a systematic, multimodal approach to neuroprognostication. It also highlights evidence gaps.

Inotrope versus placebo therapy in cardiogenic shock: Rationale and study design of the CAPITAL DOREMI2 trial.

BACKGROUND: Cardiogenic shock (CS) is a state of end-organ hypoperfusion related to cardiac dysfunction. Current guidelines recommend consideration of inotrope therapy in patients with CS, however no robust data support their use. The purpose of the CAPITAL DOREMI2 trial is to examine the efficacy and safety of inotrope therapy against placebo in the initial resuscitation of patients with CS. METHODS AND DESIGN: This is a multi-center, double-blind, randomized, placebo-controlled trial comparing single-agent inotrope therapy to placebo in patients with CS. A total of 346 participants with Society for Cardiovascular Angiography and Interventions class C or D CS will be randomized in a 1:1 fashion to inotrope or placebo therapy, which will be administered over a 12-hour period. After this period, participants will continue open-label therapies at the discretion of the treating team. The primary outcome is a composite of all-cause in-hospital death, and, as measured during the 12-hour intervention period, any of: sustained hypotension or high dose vasopressor requirements, lactate greater than 3.5 mmol/L at 6 hours or thereafter, need for mechanical circulatory support, arrhythmia leading to emergent electrical cardioversion, and resuscitated cardiac arrest. All participants will be followed for the duration of their hospitalization, and secondary outcomes will be assessed at the time of discharge. IMPLICATION: This trial will be the first to establish the safety and efficacy of inotrope therapy against placebo in a population of patients with CS and has the potential to alter the standard care provided to this group of patients.

Early Versus Delayed Coronary Angiography After Out-of-Hospital Cardiac Arrest Without ST-Segment Elevation-A Systematic Review and Meta-Analysis of Randomized Controlled Trials.

The optimal timing of coronary angiography remains unclear following out-of-hospital cardiac arrest (OHCA) without ST elevation on electrocardiogram. The objective of this systematic review and meta-analysis was to evaluate the efficacy and safety of early angiography versus delayed angiography following OHCA without ST elevation. DATA SOURCES: The databases MEDLINE, PubMed EMBASE, and CINHAL, as well as unpublished sources from inception to March 9, 2022. STUDY SELECTION: A systematic search was performed for randomized controlled trials of adult patients after OHCA without ST elevation who were randomized to early as compared to delayed angiography. DATA EXTRACTION: Reviewers screened and abstracted data independently and in duplicate. The certainty of evidence was assessed for each outcome using the Grading Recommendations Assessment, Development and Evaluation approach. The protocol was preregistered (CRD 42021292228). DATA SYNTHESIS: Six trials were included (n = 1,590 patients). Early angiography probably has no effect on mortality (relative risk [RR] 1.04; 95% CI 0.94-1.15; moderate certainty) and may have no effect on survival with good neurologic outcome (RR 0.97; 95% CI 0.87-1.07; low certainty) or ICU length of stay (LOS) (mean difference 0.41 days fewer; 95% CI -1.3 to 0.5 d; low certainty). Early angiography has an uncertain effect on adverse events. CONCLUSIONS: In OHCA patients without ST elevation, early angiography probably has no effect on mortality and may have no effect on survival with good neurologic outcome and ICU LOS. Early angiography has an uncertain effect on adverse events.

Storage conditions, sample integrity, interferences, and a decision tool for investigating unusual high-sensitivity cardiac troponin results.

The current definition of high-sensitivity cardiac troponin (hs-cTn) assays is laboratory-based and their analytical attributes and characteristics have drawn significant attention in the literature at least partly due to the lower concentration cut-offs and changes in concentrations (i.e., deltas) employed in different algorithms and pathways to manage patient care. We propose that pre-analytical conditions such as sample type, storage conditions, and other interferences may also have a significant impact on hs-cTn concentrations and clinical management. The purpose of this literature review is to provide a summary of important pre-analytical and interference studies affecting hs-cTn concentrations. A breakdown of the literature for the major diagnostic companies providing core laboratory instrumentation (i.e., Abbott, Beckman, Ortho, Roche, and Siemens) is also provided. Finally, three cases are highlighted where knowledge of pre-analytical factors aids the hs-cTn clinically discordant investigations. This review highlights the importance of pre-analytical variables, especially storage condition, sample handling, and blood tubes used (i.e., sample type) when interpreting hs-cTn assays. Additional studies are needed to further elaborate on pre-analytical variables (i.e., centrifugation, sample type, stability) and interferences for all hs-cTn assays in clinical use, as knowledge of these variables may aid in hs-cTn clinically discordant investigations.

VDI pacing with temporary esophageal and transvenous pacemaker leads to treat post-cardiac surgery cardiogenic shock.

BACKGROUND: Post-operative atrio-ventricular (AV) block after cardiac surgery is not uncommon in high-risk patients. CASE PRESENTATION: Our case highlights the management of a 62-year-old female with cardiogenic shock post-cardiac surgery with concomitant complete heart block. With VVI pacing proving ineffective, it was postulated that the patient may benefit hemodynamically from AV sequential pacing, re-establishing her atrial kick. We describe a novel technique of attaching a temporary pacemaker wire to an orogastric tube to sense atrial p-waves and pace the ventricle transvenously to perform AV sequential pacing. This was done temporarily to stabilize the patient's hemodynamic status while awaiting a permanent pacemaker implantation. CONCLUSIONS: In hemodynamically unstable post-cardiac surgery patients with complete heart block in whom VVI pacing fails to improve their clinical status, clinicians should consider VDI pacing with an orogastric atrial sensing pacemaker lead, in consultation with the cardiac surgeon and the electrophysiology team. Of note, the patient needs to have underlying organized atrial activity for this setup to work.

Can the Addition of NT-proBNP and Glucose Measurements Improve the Prognostication of High-Sensitivity Cardiac Troponin Measurements for Patients with Suspected Acute Coronary Syndrome?

Guidelines published in 2021 have supported natriuretic peptide (NP) testing for the prognostication in patients with acute coronary syndrome (ACS) and for the diagnosis of chronic and acute heart failure (HF). Our objective was to determine if the addition of N-terminal pro B-type NP (NT-proBNP) and glucose to high-sensitivity cardiac troponin (hs-cTn) could better identify emergency department (ED) patients with potential ACS at low- and high-risk for a serious cardiovascular outcome over the next 72 h. The presentation sample in two different ED cohorts which enrolled patients with symptoms suggestive of ACS within six hours of pain onset (Cohort-1, n = 126 and Cohort-2, n = 143) that had Abbott hs-cTnI, Roche hs-cTnT, NT-proBNP and glucose were evaluated for NT-proBNP alone and combined with hs-cTn and glucose for the primary outcome (composite which included death, myocardial infarction, HF, serious arrhythmia and refractory angina) via receiver-operating characteristic (ROC) curve analyses with area under the curve (AUC) and diagnostic estimates derived. The AUC for NT-proBNP for the primary outcome was 0.68 (95% confidence interval (CI): 0.59-0.76) and 0.75 (95%CI: 0.67-0.82) in Cohort-1 and 2, respectively, with the 125 ng/L cutoff yielding a higher sensitivity (≥75%) as compared to the 300 ng/L cutoff (≥58%). Using the 125 ng/L cutoff for NT-proBNP with the published glucose and hs-cTn cutoffs for risk-stratification produced a new score (GuIDER score for Glucose, Injury and Dysfunction in the Emergency-setting for cardiovascular-Risk) and yielded higher AUCs as compared to NT-proBNP (p < 0.05). GuIDER scores of 0 and 5 using either hs-cTnI/T yielded sensitivity estimates of 100% and specificity estimates > 92% for the primary outcome. A secondary analysis assessing MI alone in the overall population (combined Cohorts 1 and 2) also achieved 100% sensitivity for MI with a GuIDER cutoff ≥ 2, ruling-out 48% (Roche) and 38% (Abbott) of the population at presentation for MI. Additional studies are needed for the GuIDER score in both the acute and ambulatory setting to further refine the utility, however, the preliminary findings reported here may present a pathway forward for inclusion of NP testing for ruling-out serious cardiac events and MI in the emergency setting.

Pulmonary artery catheterization in patients with cardiogenic shock: a systematic review and meta-analysis.

PURPOSE: Cardiogenic shock carries high morbidity and mortality. The purpose of this review was to determine the safety and efficacy of pulmonary artery catheterization (PAC) in adult patients hospitalized with cardiogenic shock. SOURCE: We performed a systematic review and meta-analysis of observational studies and randomized controlled trials comparing PAC vs no PAC in cardiogenic shock. We searched MEDLINE, EMBASE, Cochrane CENTRAL, and grey literature. We screened articles, abstracted data, and evaluated risk of bias in duplicate. We pooled data using a random-effects model and evaluated the quality of evidence using the GRADE framework. Outcomes of interest were mortality, length of stay, and procedural complications. PRINCIPAL FINDINGS: We identified 19 eligible observational studies (≥ 2,716,287 patients) and no randomized controlled trials; 14 studies were at high risk of bias (lack of adjustment for prognostic variables and/or co-interventions). When pooling adjusted results, PAC was associated with improved survival to hospital discharge (relative risk [RR], 0.77; 95% confidence interval [CI], 0.64 to 0.91, I2 = 98%; very low-quality evidence) and at longest available follow-up (RR, 0.72; 95% CI, 0.60 to 0.87; I2 = 99%; very low-quality evidence). Unadjusted length of stay was 3.5 days longer (95% CI, 1.49 to 5.54; I2 = 100%; very low-quality evidence) with PAC. Procedural complications were inconsistently reported. CONCLUSIONS: Very low-quality observational evidence suggests PAC use in patients with cardiogenic shock is associated with lower mortality. Overall, these results support consideration of PAC for hemodynamic assessment in cardiogenic shock. Prospective randomized clinical trials are needed to further characterize the role of PAC in this population.

RéSUMé: OBJECTIF: Le choc cardiogénique entraîne une morbidité et une mortalité élevées. Le but de cette revue était de déterminer la sécurité et l'efficacité de l'utilisation d'un cathétérisme de l'artère pulmonaire (CAP) chez des patients adultes hospitalisés en choc cardiogénique. SOURCES: Nous avons réalisé une revue systématique et une méta-analyse d'études observationnelles et d'études randomisées contrôlées comparant l'utilisation vs la non-utilisation de CAP pour le traitement d'un choc cardiogénique. Nous avons effectué des recherches dans les bases de données MEDLINE, EMBASE, Cochrane CENTRAL et dans la littérature grise. Nous avons examiné les articles, résumé les données et évalué le risque de biais à deux reprises. Nous avons regroupé les données à l'aide d'un modèle à effets aléatoires et évalué la qualité des données probantes en nous appuyant sur le système GRADE. Les issues d'intérêt étaient la mortalité, la durée de séjour et les complications procédurales. CONSTATATIONS PRINCIPALES: Nous avons identifié 19 études observationnelles admissibles (≥ 2 716 287 patients) et aucune étude randomisée contrôlée; 14 études comportaient un risque élevé de biais (absence d'ajustement sur les variables pronostiques et/ou les interventions concomitantes). En regroupant les résultats ajustés, le CAP a été associé à une meilleure survie jusqu'au congé de l'hôpital (risque relatif [RR], 0,77; intervalle de confiance [IC] à 95 %, 0,64 à 0,91, I2 = 98 %; données probantes de très faible qualité) et jusqu'au point de suivi disponible rapporté le plus lointain dans le temps (RR, 0,72; IC 95 %, 0,60 à 0,87; I2 = 99 %; données probantes de très faible qualité). La durée de séjour non ajustée était 3,5 jours plus longue (IC 95 %, 1,49 à 5,54; I2 = 100 %; données probantes de très faible qualité) avec un CAP. Les complications procédurales n'étaient par rapportées de manière uniforme. CONCLUSION: Des données observationnelles de très faible qualité suggèrent que l'utilisation d'un CAP chez des patients en choc cardiogénique est associée à une réduction de la mortalité. Dans l'ensemble, ces résultats suggèrent de considérer le CAP pour l'évaluation hémodynamique en cas de choc cardiogénique. Des études cliniques randomisées prospectives sont nécessaires pour mieux caractériser le rôle du CAP dans cette population.

Diagnostic Performance of Serial High-Sensitivity Cardiac Troponin Measurements in the Emergency Setting.

Serial high-sensitivity cardiac troponin (hsTn) testing in the emergency department (ED) and the intensive cardiac care unit may assist physicians in ruling out or ruling in acute myocardial infarction (MI). There are three major algorithms proposed for high-sensitivity cardiac troponin I (hsTnI) using serial measurements while incorporating absolute concentration changes for MI or death following ED presentation. We sought to determine the diagnostic estimates of these three algorithms and if one was superior in two different Canadian ED patient cohorts with serial hsTnI measurements. An undifferentiated ED population (Cohort-1) and an ED population with symptoms suggestive of acute coronary syndrome (ACS; Cohort-2) were clinically managed with non-hsTn testing with the hsTnI testing performed in real-time with physicians blinded to these results (i.e., hsTnI not reported). The three algorithms evaluated were the European Society of Cardiology (ESC), the High-STEACS pathway, and the COMPASS-MI algorithm. The diagnostic estimates were derived for each algorithm for the 30-day MI/death outcome for the rule-out and rule-in arm in each cohort and compared to proposed diagnostic benchmarks (i.e., sensitivity ≥ 99.0% and specificity ≥ 90.0%) with 95% confidence intervals (CI). In Cohort-1 (n = 2966 patients, 15.3% had outcome) and Cohort-2 (n = 935 patients, 15.6% had outcome), the algorithm that obtained the highest sensitivity (97.8%; 95% CI: 96.0-98.9 and 98.6%; 95% CI: 95.1-99.8, respectively) in both cohorts was COMPASS-MI. Only Cohort-2 with both the ESC and COMPASS-MI algorithms exceeded the specificity benchmark (97.0%; 95% CI: 95.5-98.0 and 96.7%; 95% CI: 95.2-97.8, respectively). Patient selection for serial hsTnI testing will affect specificity estimates, with no algorithm achieving a sensitivity ≥ 99% for 30-day MI or death.