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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.

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. 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. 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. 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.

Graphical abstract, Highlights • We present a case of severe MR due to rupture of posteromedial papillary muscle after CABG. • The patient underwent successful edge-to-edge repair using the MitraClip device. • A subset of patients with acute MR might benefit from transcatheter repair over surgery.

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.

Background/Introduction Previously validated risk scores for identifying low-risk patients after ST-segment elevation myocardial infarction (STEMI) have led to acceptance of the safety and feasibility of discharge after 48–72 hours of hospitalization, reducing hospital length of stay and costs. With ongoing improvements in outcomes, it may be possible to select patients who are safe to discharge very early (24–48 hours) but this has never been evaluated. Purpose We sought to develop and validate a novel risk score for identifying low-risk patients suitable for very early discharge (≤48 hours of hospitalization) post-STEMI. Methods We derived a novel risk score using data from patients enrolled in the Trial of Routine Aspiration Thrombectomy with PCI versus PCI alone in Patients with STEMI (TOTAL). The TOTAL database was randomly divided into a derivation cohort with 2/3 of the composite events and non-events and remaining 1/3 as the internal validation cohort. Using the derivation cohort, we identified risk factors for cardiovascular death (CV) or non-fatal cardiac arrest by performing a univariate and multivariable stepwise regression analysis of baseline clinical and angiographic characteristics. Each co-variate was assigned an integer score based on regression coefficients and the novel TOTAL risk score was developed by adding points from each risk factor profile. We externally validated the TOTAL score using data from the Radial versus Femoral Access for Coronary Intervention (RIVAL) trial. Results The TOTAL derivation cohort included 6331 participants with 287 events (CV death/cardiac arrest). Twelve independent risk-factors associated with risk of CV death and non-fatal cardiac arrest at 1 year were selected and weighted for the TOTAL risk score (Table 1). In the TOTAL validation cohort (n=3166), patients with a TOTAL score of 0–4 points (n=779 (24.6%)) were categorized as very low risk with only a 0.1% risk of CV death/cardiac arrest observed within 24 hours of hospitalization, and no further events observed between 24 hours and 30 days post-STEMI. In the RIVAL validation dataset (n=1451), patients with a TOTAL score of 0–4 points (n=737 (50.7%)) had a 0.3% risk of CV death/cardiac arrest within 24 hours, with no further events observed between 24 hours and 72 hours of hospitalization. Conclusion The TOTAL risk score identified a very low risk subset of patients for whom early discharge, 24–48 hours post-STEMI, is likely safe. These findings have the potential to change practice and support early discharge after STEMI. Funding Acknowledgement Type of funding sources: None.

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.

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.

Rapid reperfusion of the infarct-related artery is the cornerstone of therapy for the management of acute ST-elevation myocardial infarction (STEMI). Canada's geography presents unique challenges for timely delivery of reperfusion therapy for STEMI patients. The Canadian Cardiovascular Society/Canadian Association of Interventional Cardiology STEMI guideline was developed to provide advice regarding the optimal acute management of STEMI patients irrespective of where they are initially identified: in the field, at a non-percutaneous coronary intervention-capable centre or at a percutaneous coronary intervention-capable centre. We had also planned to evaluate and incorporate sex and gender considerations in the development of our recommendations. Unfortunately, inadequate enrollment of women in randomized trials, lack of publication of main outcomes stratified according to sex, and lack of inclusion of gender as a study variable in the available literature limited the feasibility of such an approach. The Grading Recommendations, Assessment, Development, and Evaluation system was used to develop specific evidence-based recommendations for the early identification of STEMI patients, practical aspects of patient transport, regional reperfusion decision-making, adjunctive prehospital interventions (oxygen, opioids, antiplatelet therapy), and procedural aspects of mechanical reperfusion (access site, thrombectomy, antithrombotic therapy, extent of revascularization). Emphasis is placed on integrating these recommendations as part of an organized regional network of STEMI care and the development of appropriate reperfusion and transportation pathways for any given region. It is anticipated that these guidelines will serve as a practical template to develop systems of care capable of providing optimal treatment for a wide range of STEMI patients.

Differences in patient classification of myocardial injury between high-sensitivity cardiac troponin (hs-cTn) assays have largely been attributed to assay design and analytical sensitivity aspects. Our objective was to compare Ortho Clinical Diagnostics’ (OCD) hs-cTnI assay to OCD’s contemporary/conventional assay (cTnI ES) and another hs-cTnI assay (Abbott hs-cTnI) in samples obtained from different emergency departments (EDs). Two different sample types were evaluated (lithium heparin and ethylenediaminetetraacetic acid (EDTA) plasma) in a non-selected ED population (study 1, n = 469 samples) and in patients for which ED physicians ordered cardiac troponin testing (study 2, n = 1147 samples), from five different EDs. The incidence of injury in study 1 was higher with the OCD hs-cTnI assay (30.9%, 95% CI: 26.9 to 35.2) compared to that of the Abbott hs-cTnI (17.3%, 95% CI: 14.1 to 21.0) and the OCD cTnI ES (15.4%, 95% CI: 12.4 to 18.9) assays, with repeat testing identifying 4.8% (95% CI: 3.0 to 7.5) of the OCD hs-cTnI results with poor reproducibility. In study 2, 4.6% (95% CI: 3.5 to 6.0) of the results were not reported for the OCD hs-cTnI assay (i.e., poor reproducibility) with 12.7% (95%CI: 8.7 to 17.8) of the OCD hs-cTnI results positive for injury being negative for injury with the Abbott hs-cTnI assay. In summary, the OCD hs-cTnI assay yields higher rates of biochemical injury with a higher rate of poor reproducible results in different ED populations.

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.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.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, IVery 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.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.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.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.

High-sensitivity cardiac troponin (hs-cTn) testing has enabled physicians to make earlier diagnostic and prognostic decisions in the hospital setting than previous cardiac troponin assays. Analytical improvements have permitted one to measure cardiac troponin precisely in the nanogram per litre (ng/L) range with hs-cTn assays which has resulted in fast 0/1-h and 0/2-h algorithms for ruling-in and ruling-out myocardial infarction. Although analytical interferences that affect the reporting of hs-cTn are uncommon, not all hs-cTn assays are designed the same nor have undergone the same clinical and analytical validations. Here, after investigating an initial case of discrepant hs-cTnI results, we report that patients with an acute phase response (e.g., patients with inflammatory or infectious illnesses) can yield high and non-reproducible results with the Ortho Clinical Diagnostics hs-cTnI assay. Compared to Abbott Diagnostics hs-cTnI, Ortho Clinical Diagnostics hs-cTnI assay misclassifies biochemical injury in approximately 10% of the population being assessed for myocardial injury with imprecise results in approximately half of this population (i.e., 5%). In conclusion, caution is warranted in interpreting Ortho Clinical Diagnostics hs-cTnI alone in patients being evaluated for myocardial injury, especially in patients whose primary presentation is related to an acute phase response and not an acute coronary syndrome symptom.

Background Since the inception of clinical guidelines on the management of patients with acute coronary syndrome (ACS), betablocker therapy has been included as a class I recommendation. However, most studies evaluating betablockers in ACS were conducted in the pre-reperfusion era. Currently, the great majority of patients undergo reperfusion and secondary prevention therapy has evolved; the impact of treatment with a betablocker in these patients may be different. Purpose We conducted a systematic review and meta-analysis to evaluate the impact of betablockers on mortality in patients after an ACS in the reperfusion era. Methods We searched MEDLINE, EMBASE, and Cochrane Central Registry of Controlled Trials for RCTs from inception to September 2019. We included randomized controlled trials comparing betablockers to no betablockers in adult patients presenting with an ACS. Independently and in duplicate, we screened titles and abstracts, reviewed the full-text report of potentially eligible studies and extracted data. Two reviewers also evaluated the risk of bias in duplicate. Disagreements were addressed by consensus. We considered trials to be conducted in the reperfusion era if reperfusion was attempted in more than 50% of patients, either with thrombolytics or primary angioplasty. Our primary outcome of interest was all-cause mortality. Secondary outcomes included hospitalization for heart failure, nonfatal myocardial infarction, stroke and cardiogenic shock. We pooled trial outcomes using a fixed effects model. The study protocol is registered with PROSPERO (CRD42019143158). Results After the initial screening of 10,969 references and full-text review of 176 articles, nine RCTs comprising a total of 49,639 patients with ACS were eligible for the final analysis. Predominantly, these patients presented with ST elevation myocardial infarction. Treatment with a betablocker did not improve all-cause mortality at 30 days (risk ratio (RR) 0.98 [95% CI 0.92–1.04], I2=44%), or at longest follow up (up to three years) with RR 0.97 ([95% CI 0.91–1.03], I2=0%). Betablocker therapy was associated with an increased risk of HF hospitalization (RR 1.10 [95% CI 1.05–1.15], I2=52%) and cardiogenic shock during index hospitalization (RR 1.29, [95% CI 1.18–1.40], I2=0%). However, betablocker therapy reduced the risk of nonfatal myocardial infarction (RR 0.72 [95% CI 0.63–0.83], I2=0%); it did not impact the risk of stroke (RR 1.13 [95% CI 0.95–1.35], I2=0%). Conclusion In the reperfusion era, betablocker therapy after an ACS does not appear to improve short or long-term survival. Although betablocker therapy was associated with a reduction in nonfatal myocardial infarction, it increased the risk of heart failure hospitalization and cardiogenic shock. In light of these findings, clinical guidelines should reconsider the strength of their recommendation for betablocker use in the ACS population until further contemporary evidence is available. Funding Acknowledgement Type of funding source: None

Key Points Question Do treatments recommended by a heart team differ from those recommended by an original treating interventional cardiologist for patients with multivessel coronary artery disease? Findings In this cross-sectional study of 245 patients with multivessel coronary artery disease, heart team treatment recommendations indicated moderate agreement (with discordance in 30% of cases) with the original treating interventional cardiologist. Unanimous decisions within the heart team and agreement between the heart team interventional cardiologist and the original treating interventional cardiologist were less frequent in this subset of cases, while interventional cardiologist recommendations for angioplasty and medication therapy were more frequent. Meaning The study’s findings indicated that heart team recommendations differed from those of the original treating interventional cardiologist in approximately one-third of cases; this subset of cases was associated with a greater number of divergent opinions between interventional cardiologists and within the heart team., Importance Although the heart team approach is recommended in revascularization guidelines, the frequency with which heart team decisions differ from those of the original treating interventional cardiologist is unknown. Objective To examine the difference in decisions between the heart team and the original treating interventional cardiologist for the treatment of patients with multivessel coronary artery disease. Design, Setting, and Participants In this cross-sectional study, 245 consecutive patients with multivessel coronary artery disease were recruited from 1 high-volume tertiary care referral center (185 patients were enrolled through a screening process, and 60 patients were retrospectively enrolled from the center’s database). A total of 237 patients were included in the final virtual heart team analysis. Treatment decisions (which comprised coronary artery bypass grafting, percutaneous coronary intervention, and medication therapy) were made by the original treating interventional cardiologists between March 15, 2012, and October 20, 2014. These decisions were then compared with pooled-majority treatment decisions made by 8 blinded heart teams using structured online case presentations between October 1, 2017, and October 15, 2018. The randomized members of the heart teams comprised experts from 3 domains, with each team containing 1 noninvasive cardiologist, 1 interventional cardiologist, and 1 cardiovascular surgeon. Cases in which all 3 of the heart team members disagreed and cases in which procedural discordance occurred (eg, 2 members chose coronary artery bypass grafting and 1 member chose percutaneous coronary intervention) were discussed in a face-to-face heart team review in October 2018 to obtain pooled-majority decisions. Data were analyzed from May 6, 2019, to April 22, 2020. Main Outcomes and Measures The Cohen κ coefficient between the treatment recommendation from the heart team and the treatment recommendation from the original treating interventional cardiologist. Results Among 234 of 237 patients (98.7%) in the analysis for whom complete data were available, the mean (SD) age was 67.8 (10.9) years; 176 patients (75.2%) were male, and 191 patients (81.4%) had stenosis in 3 epicardial coronary vessels. A total of 71 differences (30.3%; 95% CI, 24.5%-36.7%) in treatment decisions between the heart team and the original treating interventional cardiologist occurred, with a Cohen κ of 0.478 (95% CI, 0.336-0.540; P = .006). The heart team decision was more frequently unanimous when it was concordant with the decision of the original treating interventional cardiologist (109 of 163 cases [66.9%]) compared with when it was discordant (28 of 71 cases [39.4%]; P, This cross-sectional study examines the differences in treatment decisions between a heart team and an original treating interventional cardiologist for patients with multivessel coronary artery disease.

Background Analytical comparisons between different high-sensitivity cardiac troponin (hs-cTn) assays are important for reassurance of results performed with different methodologies and to identify potential interferences or confounders to result interpretation. Our objective in the present study was to compare Beckman Coulter’s latest hs-cTnI assay to Abbott’s hs-cTnI assay and to assess agreement between results. Methods Two hundred ethylenediaminetetraacetic acid plasma samples that had clinically reported hs-cTnI results from the Abbott ARCHITECTi2000 that spanned the analytical range were stored (median = 4 h), re-centrifuged and retested for hs-cTnI on the Abbott ARCHITECTi1000 and Beckman Coulter Access2 analysers. Passing–Bablok regression and fold-differences were evaluated, with differences approximately three-fold between results further subjected to Roche hs-cTnT testing and polyethylene glycol precipitation. Results The Beckman and Abbott hs-cTnI concentrations were correlated ( r = 0.95) with Beckman yielding proportionally lower concentrations (slope = 0.78; 95%CI: 0.74–0.85). There were 12 samples that yielded Abbott hs-TnI concentrations ≥3-fold higher than the Beckman hs-cTnI concentrations; of which nine samples from seven different patients had sufficient quantity for additional testing. All seven patients had macrocomplexes as determined with polyethylene glycol precipitation that affected the Abbott hs-cTnI assay. One patient with Abbott hs-cTnI results >1300 ng/L had polyethylene glycol, heterophile antibodies and creatine kinase-MB testing performed which confirmed that a macrocomplex most likely affected the Abbott and Roche (hs-cTnT = 65 ng/L) assays but not the Beckman (hs-cTnI = 12 ng/L) assay. Conclusion The hs-cTnI concentrations obtained from ethylenediaminetetraacetic acid plasma between the Beckman and Abbott assays are highly correlated, with large differences in concentrations (≥3-fold) between Abbott and Beckman assays possible due to macrocomplexes.

Out of hospital cardiac arrest (OHCA) is associated with a low rate of survival to hospital discharge and high rates of neurological morbidity among survivors. Programmatic efforts to institute and integrate OHCA best care practices from the bystander response through to the in-hospital phase have been associated with improved patient outcomes. This Canadian Cardiovascular Society position statement was developed to provide comprehensive yet practical recommendations to guide the in-hospital care of OHCA patients. Using the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) system recommendations have been generated. Recommendations on initial care delivery on the basis of presenting rhythm, appropriate use of targeted temperature management, postarrest angiography, and revascularization in the initial phase of care of the OHCA patient are detailed within this statement. In addition, further description of best practices on sedation, use of neuromuscular blockade, oxygenation targets, hemodynamic monitoring, and blood product transfusion triggers in the critical care environment are contained in this document. Last, discussion of optimal care systems for the OHCA patient is provided. These guidelines aim to serve as a practical guide to optimize the in-hospital care of survivors of cardiac arrest and encourage the adoption of "best practice" protocols and treatment pathways. Emphasis is placed on integrating these aspects of in-hospital care as part of a postarrest "care bundle." It is hoped that this position statement can assist all medical professionals who treat survivors of cardiac arrest.

Background Cardiogenic shock carries high morbidity and mortality. Pulmonary artery catheterization (PAC) allows invasive hemodynamic assessment and tailored therapy; however, evidence supporting this practice is sparse. Methods We performed a systematic review and meta-analysis of observational studies and randomized controlled trials comparing PAC versus no PAC in cardiogenic shock. We searched MEDLINE, EMBASE, Cochrane CENTRAL, and grey literature. We screened references, abstracted data and evaluated risk of bias in duplicate. We pooled data using a random-effects model and evaluated the quality of evidence using GRADE. Outcomes of interest were mortality and length of stay (LOS). Results We identified 13 observational studies (1,982,047 patients) and no randomized controlled trials; 12 studies were at high risk of bias. When pooling adjusted results, PAC was associated with reduced mortality at hospital discharge (RR 0.64; 95% CI 0.50–0.82) and at longest available follow-up (RR 0.65; 95% CI 0.49–0.87). Unadjusted LOS was 5.0 days longer (95% CI 4.93–5.07) with PAC. Quality of evidence was very low for all outcomes. Conclusion Based on very low quality evidence, PAC use in patients with cardiogenic shock may be associated with lower mortality. The observed increase in hospital LOS may represent survivor bias or relate to more aggressive management with PAC. Overall, these results support consideration of PAC for hemodynamic assessment and tailored therapy in cardiogenic shock. Funding Acknowledgement Type of funding source: None

Medical care in Canadian cardiac units has changed considerably over the past 3 decades in response to an increasingly complex and diverse patient population admitted with acute cardiac pathology. To maintain the highest level of care for these patients, there is a pressing need to evolve traditional coronary care units into contemporary cardiac intensive care units. In this article we aim to highlight the current variations in Canadian units, develop approaches to overcome logistical and infrastructural obstacles, and propose staffing and training recommendations that would allow for the establishment of contemporary cardiac intensive care units.

Background: The role of inpatient transthoracic echocardiography (TTE) in patients with acute pulmonary embolism (PE) is unclear. Although right ventricular dysfunction (RVD) predicts adverse outcomes in acute PE, there is no consensus on the optimal TTE findings for prognostication and how they influence management, particularly when CT and/or an elevated cardiac troponin already suggest RVD. Understanding current practices regarding inpatient TTE in acute PE can help direct appropriate use. Our objectives were to (i) characterize inpatient TTE use in adult patients hospitalized with acute PE, (ii) describe and compare findings of RVD by TTE, CT and troponin, and (iii) explore differences in outcomes between patients managed with or without TTE. Methods: We conducted a retrospective cohort study of adult patients hospitalized with acute PE at two academic hospitals in Hamilton, Canada between January and December 2018. Patients with suspected PE that was not objectively confirmed, or PE diagnosed prior to hospitalization were excluded. We also excluded patients who had a TTE prior to the diagnosis of PE. Chi-square tests and independent t-tests were used. P-values less than 0.05 were considered significant. Results: We identified 178 adult patients (mean age 66 ± 15 years; 42% male). Patients were admitted to internal medicine (53%), oncology (19%), surgical specialties (13%) and intensive care units (ICU, 11%). Of 146 patients, 134 (92%) had a PE involving segmental or larger vessels. TTE was conducted in 86 (48%) patients. Systemic thrombolysis was administered to 11 (6%) patients. A higher proportion of patients with an elevated troponin (66% vs. 35% p Patients with RV strain on CT were more likely to have RV enlargement (58% vs. 30%, p=0.04) and RVD (58% vs. 25%, p=0.011) on TTE. However, right ventricular internal dimension in diastole (RVIDd) (3.9 ± 0.75 cm vs. 3.7 ± 0.78 cm) and tricuspid annular plane systolic excursion (TAPSE) (1.8 ± 0.44 cm vs. 2.0 ± 0.38 cm) were not statistically different between patients with or without RV strain on CT. A higher proportion of patients with an elevated troponin had RV enlargement (58% vs. 14%, p=0.001) and RVD (50% vs. 18%, p=0.018) on TTE. Length of hospital admission (16 ± 28 days vs. 11 ± 23 days) and in-hospital death (7% vs. 11%) were not statistically different between patients with or without TTE. Conclusions: Inpatient TTE is conducted frequently in hospitalized patients with acute PE, especially in those with evidence of RV strain based on CT and/or an elevated cardiac troponin. Our results suggest that patients with findings of RV strain on CT are more likely to have RV enlargement and RVD on TTE. Future studies should evaluate the diagnostic utility of CT and/or troponin for RVD in the setting of acute PE, which may reduce the routine use of inpatient TTE and associated healthcare resources and costs. Disclosures Mithoowani: Leo Pharma: Honoraria. Siegal:Portola: Honoraria; Novartis: Honoraria; Leo Pharma: Honoraria; Bayer: Honoraria; BMS Pfizer: Honoraria.

BACKGROUND Elevated and non-changing high-sensitivity cardiac troponin (hs-cTn) concentrations may suggest a process other than acute injury, possibly due to chronic condition(s) causing the elevation, an analytical error/interference or the formation of macrocomplexes. Heart-type fatty acid binding protein (H-FABP) might be useful in this setting to identify the etiology of abnormally high and non-changing cTn concentrations which could aid clinical decision making in the hospital setting. METHODS We analytically validated the H-FABP assay (Randox) on the Abbott ARICHTECTc8000 platform, testing imprecision, linearity, stability, and matrix comparison. Over the 2-month analytical validation; EDTA plasma samples from patients with a hospital visit with persistently elevated and stable cTnI concentrations (Abbott hs-cTnI≥52 ng/L or 2x99th percentile upper limit of normal (ULN = 26 ng/L) with change between results

Identifying modifiable factors associated with survival following in-hospital cardiac arrest is crucial. The purpose of this study was to determine the extent to which adherence to the 2010 American Heart Association (AHA) Advanced Cardiac Life Support (ACLS) guidelines in their entirety affects patient outcomes. In addition, we explored the role of code leader training level on patient outcomes.We conducted a retrospective review of records for cardiac arrests that occurred on hospital wards and were run by the hospital code team, at three tertiary care centres over 2 to 4 years. Deviations from the ACLS guidelines were quantified using a standardized checklist. Primary outcomes included return of spontaneous circulation (ROSC) and survival to hospital discharge.Of 160 resuscitation events, ROSC was achieved in 75 events (46.9%) and survival to hospital discharge in 20 patients (13.1%). On average, there were 2.3 deviations from ACLS guidelines during events that led to ROSC and 3.9 deviations during events that did not lead to ROSC (p 0.0001). There were fewer deviations during events that led to survival to hospital discharge (2.1) compared to those where the patient did not survive to hospital discharge (3.1; p = 0.016). Code leader training level was not associated with patient outcomes. Multivariable logistic regression analysis confirmed an association between deviations from ACLS guidelines and ROSC, but not for survival to hospital discharge. The latter finding may reflect a very low survival rate.We found that higher numbers of deviations from ACLS guidelines were associated with a lower likelihood of ROSC and survival to hospital discharge. These findings emphasize the importance of adherence to ACLS guidelines and the need for training healthcare personnel in resuscitation guidelines in order to improve outcomes for victims of in-hospital cardiac arrest.

Lithium is commonly prescribed for mood stabilization in bipolar disorder. Lithium has a narrow therapeutic range (0.8−1.2 mmol/L), and even chronic users may unexpectedly develop toxic levels. Toxicities manifest in various ways. The authors report the case of a patient who developed sinus bradycardia and asystolic arrest with an elevated serum lithium level.

The passenger lymphocyte syndrome (PLS), often associated with immune-mediated hemolytic anemia after solid organ and hematopoietic stem cell transplantation, is the result of concomitant transplantation of donor lymphocytes along with the donor allograft. Antibodies directed against recipient red blood cells (RBCs) are frequently found in ABO-mismatched solid organ transplants; however, passenger lymphocyte-mediated hemolysis due to Rh-incompatible antibodies has only rarely been reported. In this report, we present a case of severe hemolytic anemia related to the PLS in an ABO-matched renal allograft recipient. The recipient's blood type was A Rh(D) positive; and the donor, who had been previously alloimmunized, was A Rh(D) negative. The renal allograft recipient's hemoglobin abruptly decreased on postoperative day 12 in the setting of a newly positive direct antiglobulin test and anti-D antibodies in the plasma. The patient required intermittent RBC transfusions for ongoing hemolysis during the first 6 months post-renal transplant. Of all reported cases of anti-D-mediated PLS, our patient would seem to have been one of the most severe, as indicated by a nadir hemoglobin of 41 g/L and the need for 23 U of transfused RBCs. A hemolytic anemia occurring after organ transplantation should raise the possibility of donor-derived antibodies directed against the recipient RBCs. Passenger lymphocyte syndrome-associated hemolysis is occasionally severe as in our case, but can be effectively treated with compatible RBC transfusions.

OBJECTIVE: To achieve national consensus on standards of training, quality assurance and maintenance of competence for critical care ultrasound for intensivists and critical care trainees in Canada using recently published international training statements.DATA SOURCES: Existing internationally endorsed guidelines and expert opinion.DATA SYNTHESIS: In November 2013, a day-long consensus meeting was held with 15 Canadian experts in critical care ultrasound in which essential topics relevant to training ultrasound were discussed.CONCLUSIONS: Consensus was achieved to direct training curriculum, oversight, quality assurance and maintenance of competence for critical care ultrasound. In providing the first national guideline of its kind, these Canadian recommendations may also serve as a model of critical care ultrasound dissemination for other countries.

Angiofollicular lymph node hyperplasia, known more commonly as Castleman disease, is a rare lymphoproliferative disorder. Castleman disease has two distinct clinical manifestations described as unicentric and multicentric disease. These presentations have distinct treatment algorithms and portend very different prognoses. Standard treatment of unicentric disease is complete surgical resection, which confers a cure rate approaching 100%. To our knowledge, this case report is the first to describe the use of neoadjuvant rituximab in the treatment of unicentric Castleman disease to enable a less morbid surgical resection. Given the vascularity of the tumor, proximity to the pulmonary artery and superior vena cava, and possible intimate association with the lung parenchyma, the tumor was treated preoperatively with rituximab, an anti-CD20 monoclonal antibody, at doses of 375 mg/m 2 weekly for 4 weeks. Rituximab therapy successfully decreased the diameter of the tumor from 4.79 cm×2.67 cm to 2.8 cm×1.5 cm, as confirmed by CT imaging. Postoperative surgical pathology confirmed the diagnosis of Castleman disease, hyaline vascular type, with negative margins. Notably, the lymph node tissue in the rituximab-treated specimen demonstrated reduced mantle zone thickness, decreased size of follicles, and increased hyalinization of vessels. Rituximab shows promise in neoadjuvant treatment of unresectable or partially resectable unicentric Castleman disease.