Modern Clinical Mycobacterium tuberculosis Strains Leverage Type I IFN Pathway for a Proinflammatory Response in the Host.

Host phagocytes respond to infections by innate defense mechanisms through metabolic shuffling to restrict the invading pathogen. However, this very plasticity of the host provides an ideal platform for pathogen-mediated manipulation. In the human (THP1/THP1 dual/PBMC-derived monocyte-derived macrophages) and mouse (RAW264.7 and C57BL/6 bone marrow-derived) macrophage models of Mycobacterium tuberculosis infection, we have identified an important strategy employed by clinical lineages in regulating the host immune-metabolism axis. We show greater transit via the macrophage phagosomal compartments by Mycobacterium tuberculosis strains of lineage: M. tuberculosis lineage 3 is associated with an ability to elicit a strong and early type I IFN response dependent on DNA (in contrast with the protracted response to lineage: M. tuberculosis lineage 1). This augmented IFN signaling supported a positive regulatory loop for the enhanced expression of IL-6 consequent to an increase in the expression of 25-hydroxycholesterol in macrophages. This amplification of the macrophage innate response-metabolic axis incumbent on a heightened and early type I IFN signaling portrays yet another novel aspect of improved intracellular survival of clinical M. tuberculosis strains.

Days alive and out of hospital for adult female and male cardiac surgery patients: a population-based cohort study.

BACKGROUND: Research shows women experience higher mortality than men after cardiac surgery but information on sex-differences during postoperative recovery is limited. Days alive and out of hospital (DAH) combines death, readmission and length of stay, and may better quantify sex-differences during recovery. This main objective is to evaluate (i) how DAH at 30-days varies between sex and surgical procedure, (ii) DAH responsiveness to patient and surgical complexity, and (iii) longer-term prognostic value of DAH. METHODS: We evaluated 111,430 patients (26% female) who underwent one of three types of cardiac surgery (isolated coronary artery bypass [CABG], isolated non-CABG, combination procedures) between 2009 - 2019. Primary outcome was DAH at 30 days (DAH30), secondary outcomes were DAH at 90 days (DAH90) and 180 days (DAH180). Data were stratified by sex and surgical group. Unadjusted and risk-adjusted analyses were conducted to determine the association of DAH with patient-, surgery-, and hospital-level characteristics. Patients were divided into two groups (below and above the 10th percentile) based on the number of days at DAH30. Proportion of patients below the 10th percentile at DAH30 that remained in this group at DAH90 and DAH180 were determined. RESULTS: DAH30 were lower for women compared to men (22 vs. 23 days), and seen across all surgical groups (isolated CABG 23 vs. 24, isolated non-CABG 22 vs. 23, combined surgeries 19 vs. 21 days). Clinical risk factors including multimorbidity, socioeconomic status and surgical complexity were associated with lower DAH30 values, but women showed lower values of DAH30 compared to men for many factors. Among patients in the lowest 10th percentile at DAH30, 80% of both females and males remained in the lowest 10th percentile at 90 days, while 72% of females and 76% males remained in that percentile at 180 days. CONCLUSION: DAH is a responsive outcome to differences in patient and surgical risk factors. Further research is needed to identify new care pathways to reduce disparities in outcomes between male and female patients.

A Prospective Cohort Study of Acute Pain and In-Hospital Opioid Consumption After Cardiac Surgery: Associations With Psychological and Medical Factors and Chronic Postsurgical Pain.

BACKGROUND: Understanding the association of acute pain intensity and opioid consumption after cardiac surgery with chronic postsurgical pain (CPSP) can facilitate implementation of personalized prevention measures to improve outcomes. The objectives were to (1) examine acute pain intensity and daily mg morphine equivalent dose (MME/day) trajectories after cardiac surgery, (2) identify factors associated with pain intensity and opioid consumption trajectories, and (3) assess whether pain intensity and opioid consumption trajectories are risk factors for CPSP. METHODS: Prospective observational cohort study design conducted between August 2012 and June 2020 with 1-year follow-up. A total of 1115 adults undergoing cardiac surgery were recruited from the preoperative clinic. Of the 959 participants included in the analyses, 573 completed the 1-year follow-up. Main outcomes were pain intensity scores and MME/day consumption over the first 6 postoperative days (PODs) analyzed using latent growth mixture modeling (GMM). Secondary outcome was 12-month CPSP status. RESULTS: Participants were mostly male (76%), with a mean age of 61 ± 13 years. Three distinct linear acute postoperative pain intensity trajectories were identified: "initially moderate pain intensity remaining moderate" (n = 62), "initially mild pain intensity remaining mild" (n = 221), and "initially moderate pain intensity decreasing to mild" (n = 251). Age, sex, emotional distress in response to bodily sensations, and sensitivity to pain traumatization were significantly associated with pain intensity trajectories. Three distinct opioid consumption trajectories were identified on the log MME/day: "initially high level of MME/day gradually decreasing" (n = 89), "initially low level of MME/day remaining low" (n = 108), and "initially moderate level of MME/day decreasing to low" (n = 329). Age and emotional distress in response to bodily sensations were associated with trajectory membership. Individuals in the "initially mild pain intensity remaining mild" trajectory were less likely than those in the "initially moderate pain intensity remaining moderate" trajectory to report CPSP (odds ratio [95% confidence interval, CI], 0.23 [0.06-0.88]). No significant associations were observed between opioid consumption trajectory membership and CPSP status (odds ratio [95% CI], 0.84 [0.28-2.54] and 0.95 [0.22-4.13]). CONCLUSIONS: Those with moderate pain intensity right after surgery are more likely to develop CPSP suggesting that those patients should be flagged early on in their postoperative recovery to attempt to alter their trajectory and prevent CPSP. Emotional distress in response to bodily sensations is the only consistent modifiable factor associated with both pain and opioid trajectories.

Prevalence and Risk Factors for Chronic Postsurgical Pain After Thoracic Surgery: A Prospective Cohort Study.

OBJECTIVE: Thoracic surgery is associated with one of the highest rates of chronic postsurgical pain (CPSP) among all surgical subtypes. Chronic postsurgical pain carries significant medical, psychological, and economic consequences, and further interventions are needed to prevent its development. This study aimed to determine the prevalence, characteristics, and risk factors associated with CPSP after thoracic surgery. DESIGN: A prospective cohort study. SETTING: Single-center tertiary care hospital. PARTICIPANTS: This study included 285 adult patients who underwent thoracic surgery at Toronto General Hospital in Toronto, Canada, between 2012 and 2020. MEASUREMENTS AND MAIN RESULTS: Demographic, psychological, and clinical data were collected perioperatively, and follow-up evaluations were administered at 3, 6, and 12 months after surgery to assess CPSP. Chronic postsurgical pain was reported in 32.4%, 25.4%, and 18.2% of patients at 3, 6, and 12 months postoperatively, respectively. Average CPSP pain intensity was rated to be 3.37 (SD 1.82) at 3 months. Features of neuropathic pain were present in 48.7% of patients with CPSP at 3 months and 71% at 1 year. Multivariate logistic regression models indicated that independent predictors for CPSP at 3 months were scores on the Hospital Anxiety and Depression Scale (adjusted odds ratio [aOR] of 1.07, 95% CI of 1.02 to 1.14, p = 0.012) and acute postoperative pain (aOR of 2.75, 95% CI of 1.19 to 6.36, p = 0.018). INTERVENTIONS: None. CONCLUSIONS: Approximately 1 in 3 patients will continue to have pain at 3 months after surgery, with a large proportion reporting neuropathic features. Risk factors for pain at 3 months may include preoperative anxiety and depression and acute postoperative pain.

Minimally invasive extracorporeal circulation versus conventional cardiopulmonary bypass in patients undergoing cardiac surgery (MiECS): Rationale and design of a multicentre randomised trial.

INTRODUCTION: The ultimate answer to the question whether minimal invasive extracorporeal circulation (MiECC) represents the optimal perfusion technique in contemporary clinical practice remains elusive. The present study is a real-world study that focuses on specific perfusion-related clinical outcomes after cardiac surgery that could potentially be favourably affected by MiECC and thereby influence the future clinical practice. METHODS: The MiECS study is an international, multi-centre, two-arm randomized controlled trial. Patients undergoing elective or urgent coronary artery bypass grafting (CABG), aortic valve replacement (AVR) or combined procedure (CABG + AVR) using extracorporeal circulation will be randomized to MiECC or contemporary conventional cardiopulmonary bypass (cCPB). Use of optimized conventional circuits as controls is acceptable. The study design includes a range of features to prevent bias and is registered at clinicaltrials.gov (NCT05487612). RESULTS: The primary outcome is a composite of postoperative serious adverse events that could be related to perfusion technique occurring up to 30 days postoperatively. Secondary outcomes include use of blood products, ICU and hospital length of stay (30 days) as well as health-related quality of life (30 and 90 days). CONCLUSIONS: The MiECS trial has been designed to overcome perceived limitation of previous trials of MiECC. Results of the proposed study could affect current perfusion practice towards advancement of patient care.

Conventional versus minimally invasive extra-corporeal circulation in patients undergoing cardiac surgery: A randomized controlled trial (COMICS).

INTRODUCTION: The trial hypothesized that minimally invasive extra-corporeal circulation (MiECC) reduces the risk of serious adverse events (SAEs) after cardiac surgery operations requiring extra-corporeal circulation without circulatory arrest. METHODS: This is a multicentre, international randomized controlled trial across fourteen cardiac surgery centres including patients aged ≥18 and <85 years undergoing elective or urgent isolated coronary artery bypass grafting (CABG), isolated aortic valve replacement (AVR) surgery, or CABG + AVR surgery. Participants were randomized to MiECC or conventional extra-corporeal circulation (CECC), stratified by centre and operation. The primary outcome was a composite of 12 post-operative SAEs up to 30 days after surgery, the risk of which MiECC was hypothesized to reduce. Secondary outcomes comprised: other SAEs; all-cause mortality; transfusion of blood products; time to discharge from intensive care and hospital; health-related quality-of-life. Analyses were performed on a modified intention-to-treat basis. RESULTS: The trial terminated early due to the COVID-19 pandemic; 1071 participants (896 isolated CABG, 97 isolated AVR, 69 CABG + AVR) with median age 66 years and median EuroSCORE II 1.24 were randomized (535 to MiECC, 536 to CECC). Twenty-six participants withdrew after randomization, 22 before and four after intervention. Fifty of 517 (9.7%) randomized to MiECC and 69/522 (13.2%) randomized to CECC group experienced the primary outcome (risk ratio = 0.732, 95% confidence interval (95% CI) = 0.556 to 0.962, p = 0.025). The risk of any SAE not contributing to the primary outcome was similarly reduced (risk ratio = 0.791, 95% CI 0.530 to 1.179, p = 0.250). CONCLUSIONS: MiECC reduces the relative risk of primary outcome events by about 25%. The risk of other SAEs was similarly reduced. Because the trial terminated early without achieving the target sample size, these potential benefits of MiECC are uncertain.

Comparative safety of tenecteplase vs alteplase for acute ischemic stroke.

INTRODUCTION: Tenecteplase has been compared to alteplase in acute stroke randomized trials, with similar outcomes and safety measures, but higher doses of tenecteplase have been associated with higher hemorrhage rates in some studies. Limited data are available on the safety of tenecteplase outside of clinical trials. METHODS: We examined the safety measures of intracranial hemorrhage, angioedema, and serious extracranial adverse events in a 21-hospital integrated healthcare system that switched from alteplase (0.9 mg/kg, maximum dose 90 mg) to tenecteplase (0.25 mg/kg, maximum dose 25 mg) for acute ischemic stroke. RESULTS: Among 3,689 subjects, no significant differences were seen between tenecteplase and alteplase in the rate of intracranial hemorrhage (ICH), parenchymal hemorrhage, or volume of parenchymal hemorrhage. Symptomatic hemorrhage (sICH) was not different between the two agents: sICH by NINDS criteria was 2.0 % for alteplase vs 2.3 % for tenecteplase (P = 0.57), and sICH by SITS criteria was 0.8 % vs 1.1 % (P = 0.39). Adjusted logistic regression models also showed no differences between tenecteplase and alteplase: the odds ratio for tenecteplase (vs alteplase) modeling sICH by NINDS criteria was 0.9 (95 % CI 0.33 - 2.46, P = 0.83) and the odds ratio for tenecteplase modeling sICH by SITS criteria was 1.12 (95 % CI 0.25 - 5.07, P = 0.89). Rates of angioedema and serious extracranial adverse events were low and did not differ between tenecteplase and alteplase. Elapsed door-to-needle times showed a small improvement after the switch to tenecteplase (51.8 % treated in under 30 min with tenecteplase vs 43.5 % with alteplase, P < 0.001). CONCLUSION: In use outside of clinical trials, complication rates are similar between tenecteplase and alteplase. In the context of a stroke telemedicine program, the rates of hemorrhage observed with either agent were lower than expected based on prior trials and registry data. The more easily prepared tenecteplase was associated with a lower door-to-needle time.

Donor and recipient human leukocyte antigen-G polymorphisms modulate the risk of adverse immunologic events following lung transplantation.

The long-term benefits of lung transplantation (LTx) are limited by pathogenic alloimmune responses that drive injury, inflammation, and chronic dysfunction. Human leukocyte antigen-G (HLA-G) plays a key role in the modulation of these pathways. This study assesses the impact of the HLA-G genotype on immunologic risk and survival following LTx. This retrospective cohort study included 289 bilateral LTx. Recipient and donor HLA-G genotypes were analyzed to identify associations with de novo donor-specific antibodies, acute rejection, chronic lung allograft dysfunction, and allograft survival. We further assessed these associations, both individually and in paired analysis, based on a grouped haplotype classification of HLA-G expression. Donor HLA-G single nucleotide polymorphisms were associated with allograft injury, the onset of chronic lung allograft dysfunction following injury, and allograft survival. Recipient HLA-G single nucleotide polymorphisms were associated with allograft injury, cellular rejection, and donor-specific antibody formation. "Low HLA-G expression" donor haplotypes were associated with impaired allograft survival, as were "low HLA-G expression" donor-recipient haplotype pairs. This study provides compelling evidence for the role of HLA-G in modulating immunologic risk after LTx. Our results highlight the importance of both donor and recipient HLA-G genotypes on the overall risk profile and underscore the lasting influence of donor genotype on lung transplant outcomes.

Extracorporeal Membrane Oxygenation for Graft Dysfunction Early After Heart Transplantation: A Systematic Review and Meta-analysis.

INTRODUCTION: Venoarterial extracorporeal membrane oxygenation (VA-ECMO) is a prevailing option for the management of severe early graft dysfunction. This systematic review and individual patient data (IPD) meta-analysis aims to evaluate (1) mortality, (2) rates of major complications, (3) prognostic factors, and (4) the effect of different VA-ECMO strategies on outcomes in adult heart transplant (HT) recipients supported with VA-ECMO. METHODS AND RESULTS: We conducted a systematic search and included studies of adults (≥18 years) who received VA-ECMO during their index hospitalization after HT and reported on mortality at any timepoint. We pooled data using random effects models. To identify prognostic factors, we analysed IPD using mixed effects logistic regression. We assessed the certainty in the evidence using the GRADE framework. We included 49 observational studies of 1477 patients who received VA-ECMO after HT, of which 15 studies provided IPD for 448 patients. There were no differences in mortality estimates between IPD and non-IPD studies. The short-term (30-day/in-hospital) mortality estimate was 33% (moderate certainty, 95% confidence interval [CI] 28%-39%) and 1-year mortality estimate 50% (moderate certainty, 95% CI 43%-57%). Recipient age (odds ratio 1.02, 95% CI 1.01-1.04) and prior sternotomy (OR 1.57, 95% CI 0.99-2.49) are associated with increased short-term mortality. There is low certainty evidence that early intraoperative cannulation and peripheral cannulation reduce the risk of short-term death. CONCLUSIONS: One-third of patients who receive VA-ECMO for early graft dysfunction do not survive 30 days or to hospital discharge, and one-half do not survive to 1 year after HT. Improving outcomes will require ongoing research focused on optimizing VA-ECMO strategies and care in the first year after HT.

Patients with fulminant myocarditis supported with veno-arterial extracorporeal membrane oxygenation: a systematic review and meta-analysis of short-term mortality and impact of risk factors.

Fulminant myocarditis (FM) may lead to cardiogenic shock requiring veno-arterial extracorporeal membrane oxygenation (VA-ECMO). Results of effectiveness studies of VA-ECMO have been contradictory. We evaluated the aggregate short-term mortality after VA-ECMO and predictive factors in patients with FM. We systematically searched in electronic databases (February 2022) to identify studies evaluating short-term mortality (defined as mortality at 30 days or in-hospital) after VA-ECMO support for FM. We included studies with 5 or more patients published after 2009. We assessed the quality of the evidence using the QUIPS and GRADE tools. Mortality was pooled using random effect models. We performed meta-regression to explore heterogeneity based on a priori defined factors. We included 54 observational studies encompassing 2388 FM patients supported with VA-ECMO. Median age was 41 years (25th to 75th percentile 37-47), and 50% were female. The pooled short-term mortality was 35% (95% CI 29-40%, I2 = 69%; moderate certainty). By meta-regression, studies with younger populations showed lower mortality. Female sex, receiving a biopsy, cardiac arrest, left ventricular unloading, and earlier recruitment time frame, did not explain heterogeneity. These results remained consistent regardless of continent and the risk of bias category. In individual studies, low pH value, high lactate, absence of functional cardiac recovery on ECMO, increased burden of malignant arrhythmia, high peak coronary markers, and IVIG use were identified as independent predictors of mortality. When conventional therapies have failed, especially in younger patients, cardiopulmonary support with VA-ECMO should be considered in the treatment of severe FM.

Relationships among norepinephrine levels, exercise capacity, and chronotropic responses in heart failure patients.

In heart failure (HF) patients, the pathophysiological mechanisms of severe exercise intolerance and impaired exercise capacity are related to both central and peripheral abnormalities. The central abnormalities in HF patients include impaired cardiac function and chronotropic incompetence (CI). Indeed, CI, the inability to adequately increase heart rate (HR) from rest to exercise often exhibited by HF patients, is related to activation of the sympathetic nervous system (SNS) yielding a rise in circulating norepinephrine (NE). CI may result from downregulation of ß-adrenergic receptors, ß-blocker usage, high baseline HR, or due to a combination of factors. This paper discusses the role of elevated NE in altering chronotropic responses in HF patients and consequently resulting in impaired exercise capacity. We suggest that future research should focus on the potential treatment of CI with rate-adaptive pacing, using a sensor to measure physical activity, without inducing deleterious hormonal activation of the sympathetic system.

Prevalence and Risk Factors for Chronic Postsurgical Pain after Cardiac Surgery: A Single-center Prospective Cohort Study.

BACKGROUND: Chronic postsurgical pain is a common complication of surgery. The role of psychologic risk factors like depression and anxiety is substantially understudied in cardiac surgery. This study sought to identify perioperative factors associated with chronic pain at 3, 6, and 12 months after cardiac surgery. The authors hypothesize that baseline psychologic vulnerabilities have a negative influence on chronic postsurgical pain. METHODS: The authors prospectively collected demographic, psychologic, and perioperative factors in a cohort of 1,059 patients undergoing cardiac surgery at the Toronto General Hospital between 2012 and 2020. Patients were followed and completed chronic pain questionnaires at 3, 6, and 12 months after surgery. RESULTS: The study included 767 patients who completed at least one follow-up questionnaire. The incidence of postsurgical pain (more than 0 out of 10) at 3, 6, and 12 months after surgery was 191 of 663 (29%), 118 of 625 (19%), and 89 of 605 (15%), respectively. Notably, among patients reporting any pain, the incidence of pain compatible with a neuropathic phenotype increased from 56 of 166 (34%) at 3 months to 38 of 97 (39%) at 6 months and 43 of 67 (64%) at 12 months. Factors associated with postsurgical pain scores at 3 months include female sex, pre-existing chronic pain, previous cardiac surgery, preoperative depression, baseline pain catastrophizing scores, and moderate-to-severe acute pain (4 or more out of 10) within 5 postoperative days. CONCLUSIONS: Nearly one in three patients undergoing cardiac surgery reported pain at 3 months of follow-up, with approximately 15% reporting persistent pain at 1 yr. Female sex, pre-existing chronic pain, and baseline depression were associated with postsurgical pain scores across all three time periods.

Minimally Invasive Aortic Valve Replacement in Contemporary Practice: Clinical and Hemodynamic Performance from a Prospective Multicenter Trial.

BACKGROUND: The advent of transcatheter aortic valve replacement (AVR) has led to an increased emphasis on reducing the invasiveness of surgical procedures. The aim of this study was to evaluate clinical outcomes and hemodynamic performance achieved with minimally invasive aortic valve replacement (MI-AVR) as compared with conventional AVR. METHODS: Patients who underwent surgical AVR with the Avalus bioprosthesis, as part of a prospective multicenter non-randomized trial, were included in this analysis. Surgical approach was left to the discretion of the surgeons. Patient characteristics and clinical outcomes were compared between MI-AVR and conventional AVR groups in the entire cohort (n = 1077) and in an isolated AVR subcohort (n = 528). Propensity score adjustment was performed to estimate the effect of MI-AVR on adverse events. RESULTS: Patients treated with MI-AVR were younger, had lower STS scores, and underwent concomitant procedures less often. Valve size implanted was comparable between the groups. MI-AVR was associated with longer procedural times in the isolated AVR subcohort. Postprocedural hemodynamic performance was comparable. There were no significant differences between MI-AVR and conventional AVR in early and 3-year all-cause mortality, thromboembolism, reintervention, or a composite of those endpoints within either the entire cohort or the isolated AVR subcohort. After propensity score adjustment, there remained no association between MI-AVR and the composite endpoint (hazard ratio: 0.86, 95% confidence interval: 0.47-1.55, p = 0.61). CONCLUSION: Three-year outcomes after MI-AVR with the Avalus bioprosthetic valve were comparable to conventional AVR. These results provide important insights into the overall ability to reduce the invasiveness of AVR without compromising outcomes.

Cold-stored platelets for acute bleeding in cardiac surgical patients: a narrative review.

PURPOSE: Cold-stored platelets (CSP) are an increasingly active topic of international research. They are maintained at 1-6 °C, in contrast to standard room-temperature platelets (RTP) kept at 20-24 °C. Recent evidence suggests that CSP have superior hemostatic properties compared with RTP. This narrative review explores the application of CSP in adult cardiac surgery, summarizes the preclinical and clinical evidence for their use, and highlights recent research. SOURCE: A targeted search of MEDLINE and other databases up to 24 February 2022 was conducted. Search terms combined concepts such as cardiac surgery, blood, platelet, and cold-stored. Searches of trial registries ClinicalTrials.gov and WHO International Clinical Trials Registry Platform were included. Articles were included if they described adult surgical patients as their population of interest and an association between CSP and clinical outcomes. References of included articles were hand searched. PRINCIPAL FINDINGS: When platelets are stored at 1-6 °C, their metabolic rate is slowed, preserving hemostatic function for increased storage duration. Cold-stored platelets have superior adhesion characteristics under physiologic shear conditions, and similar or superior aggregation responses to physiologic agonists. Cold-stored platelets undergo structural, metabolic, and molecular changes which appear to "prime" them for hemostatic activity. While preliminary, clinical evidence supports the conduct of trials comparing CSP with RTP for patients with platelet-related bleeding, such as those undergoing cardiac surgery. CONCLUSION: Cold-stored platelets may have several advantages over RTP, including increased hemostatic capacity, extended shelf-life, and reduced risk of bacterial contamination. Large clinical trials are needed to establish their potential role in the treatment of acutely bleeding patients.

RéSUMé: OBJECTIF: Les plaquettes conservées au froid (PCF) sont un sujet de recherche internationale de plus en plus populaire. Ces plaquettes sont maintenues à une température de 1-6 °C, contrairement aux plaquettes standard conservées à température ambiante (PTA), maintenues à 20­24 °C. Des données probantes récentes suggèrent que les PCF ont des propriétés hémostatiques supérieures aux PTA. Ce compte rendu narratif explore l'application de PCF en chirurgie cardiaque chez l'adulte, résume les données probantes précliniques et cliniques de leur utilisation, et met en évidence les recherches récentes. SOURCES: Une recherche ciblée dans MEDLINE et d'autres bases de données jusqu'au 24 février 2022 a été effectuée. Les termes de recherche combinaient des concepts en anglais tels que cardiac surgery, blood, platelet et cold-stored (soit chirurgie cardiaque, plaquette, et entreposage frigorifique). Des recherches dans les registres d'études ClinicalTrials.gov et le système d'enregistrement international des essais cliniques (ICTRP) de l'OMS ont été incluses. Les articles ont été inclus s'ils décrivaient des patient·es adultes de chirurgie en tant que population d'intérêt et une association entre les PCF et les issues cliniques. Les références des articles inclus ont fait l'objet d'une recherche manuelle. CONSTATATIONS PRINCIPALES: Lorsque les plaquettes sont conservées entre 1 et 6 °C, leur taux métabolique est ralenti, préservant la fonction hémostatique pour une durée d'entreposage accrue. Les plaquettes conservées au froid ont des caractéristiques d'adhésion supérieures dans des conditions de cisaillement physiologique et des réponses d'agrégation similaires ou supérieures aux agonistes physiologiques. Les plaquettes conservées au froid subissent des changements structurels, métaboliques et moléculaires qui semblent les « amorcer ¼ pour une activité hémostatique. Bien que préliminaires, les données probantes cliniques appuient la réalisation d'études comparant les PCF aux PTA chez la patientèle présentant des saignements liés aux plaquettes, tels que les personnes bénéficiant d'une chirurgie cardiaque. CONCLUSION: Les plaquettes conservées au froid peuvent présenter plusieurs avantages par rapport aux PTA, notamment une capacité hémostatique accrue, une durée de conservation prolongée et un risque réduit de contamination bactérienne. De grands essais cliniques sont nécessaires pour établir leur rôle potentiel dans le traitement de la patientèle en hémorragie aiguë.

Platelet preservation in cardiac surgery using minimally invasive extracorporeal circulation versus optimized cardiopulmonary bypass.

BACKGROUND: Minimally invasive extracorporeal circulation (MiECC) is employed as a strategy to attenuate the physiologic disturbance caused by cardiopulmonary bypass. The aim of this study was to compare the coagulation profile of MiECC to an optimized conventional extracorporeal circuit (OpECC) with regards to platelet function, rotational thromboelastometry and blood product usage. METHODS: A retrospective analysis of coronary artery bypass grafting operations using either MiECC or OpECC was performed at a single institution. RESULTS: A total of 112 patients were included, with 61 receiving MiECC and 51 OpECC patients. OpECC patients had a significantly larger BSA (1.95+/- 0.22m2 vs 1.88 +/- 0.18m2, p = 0.034), than those who received MiECC. No difference between groups was observed regarding red blood cell, plasma, and platelet transfusions. Functional platelet count during the warming phase of cardiopulmonary bypass was found to be higher in the MiECC group ((136 (102-171) x109/L vs 109 (94-136) x109/L), p = 0.027), as were functional platelets as a percent of total platelet count ((86 (77-91)% vs 76 (63-82)%), p = 0.003). There were no significant differences between other outcomes such as operative mortality, incidence of stroke, and intensive care unit length of stay. CONCLUSION: While we did not see a difference in blood transfusions, MiECC resulted in a statistically significant advantage over OpECC with regards to preservation of functional platelets.

Effect of Systolic and Diastolic Blood Pressure on Cardiovascular Outcomes.

BACKGROUND: The relationship between outpatient systolic and diastolic blood pressure and cardiovascular outcomes remains unclear and has been complicated by recently revised guidelines with two different thresholds (≥140/90 mm Hg and ≥130/80 mm Hg) for treating hypertension. METHODS: Using data from 1.3 million adults in a general outpatient population, we performed a multivariable Cox survival analysis to determine the effect of the burden of systolic and diastolic hypertension on a composite outcome of myocardial infarction, ischemic stroke, or hemorrhagic stroke over a period of 8 years. The analysis controlled for demographic characteristics and coexisting conditions. RESULTS: The burdens of systolic and diastolic hypertension each independently predicted adverse outcomes. In survival models, a continuous burden of systolic hypertension (≥140 mm Hg; hazard ratio per unit increase in z score, 1.18; 95% confidence interval [CI], 1.17 to 1.18) and diastolic hypertension (≥90 mm Hg; hazard ratio per unit increase in z score, 1.06; 95% CI, 1.06 to 1.07) independently predicted the composite outcome. Similar results were observed with the lower threshold of hypertension (≥130/80 mm Hg) and with systolic and diastolic blood pressures used as predictors without hypertension thresholds. A J-curve relation between diastolic blood pressure and outcomes was seen that was explained at least in part by age and other covariates and by a higher effect of systolic hypertension among persons in the lowest quartile of diastolic blood pressure. CONCLUSIONS: Although systolic blood-pressure elevation had a greater effect on outcomes, both systolic and diastolic hypertension independently influenced the risk of adverse cardiovascular events, regardless of the definition of hypertension (≥140/90 mm Hg or ≥130/80 mm Hg). (Funded by the Kaiser Permanente Northern California Community Benefit Program.).

Titrated versus conventional anticoagulation management for thrombin generation in cardiac surgery: a randomized controlled trial.

PURPOSE: Optimal heparin titration during cardiopulmonary bypass (CPB) may reduce coagulation system activation and preserve hemostatic function post-CPB. Our objective was to assess if the Heparin Management System (HMS) Plus improves heparin titration, thereby leading to higher thrombin generation post-CPB compared with activated clotting time (ACT)-guided management. METHODS: We conducted a randomized controlled trial of 100 patients undergoing cardiac surgery with CPB at a single center. A total of 50 patients were randomized to conventional ACT-guided management, and 50 to the HMS Plus system. The primary outcome was change in thrombin generation post-CPB compared with baseline, as assessed by calibrated automated thrombography. Secondary outcomes included intraoperative blood loss, chest drain output up to 72 hr, and transfusions. In an exploratory analysis, we compared the quintile of patients with the highest average heparin concentration on CPB (≥ 4.0 mg⋅kg-1) with the rest of the cohort. RESULTS: A total of 100 patients were included in an intent-to-treat analysis. We observed no difference in post-CPB thrombin generation or secondary outcomes. However, patients in the HMS Plus group had higher average heparin concentrations while on CPB than patients in the conventional management group did (mean difference, -0.21; 95% confidence interval, -0.42 to -0.01). The quintile of patients with the highest average heparin concentration (4.0 mg⋅kg-1) had higher thrombin generation post-CPB than the rest of the cohort did. CONCLUSIONS: The HMS Plus system did not show significant benefits in thrombin generation, bleeding outcomes, or transfusion in patients undergoing cardiac surgery with CPB. Higher average heparin concentrations on CPB were associated with higher post-CPB thrombin generation. STUDY REGISTRATION: www. CLINICALTRIALS: gov (NCT03347201); first submitted 12 October 2017.

RéSUMé: OBJECTIF: Un titrage optimal de l'héparine pendant la circulation extracorporelle (CEC) peut réduire l'activation du système de coagulation et préserver la fonction hémostatique après la CEC. Notre objectif était d'évaluer si le système de gestion de l'héparine HMS Plus améliorait le titrage de l'héparine, entraînant ainsi une génération de thrombine plus élevée après la CEC par rapport à la gestion guidée par le temps de coagulation activé (ACT). MéTHODE: Nous avons réalisé une étude randomisée contrôlée de 100 patients bénéficiant d'une chirurgie cardiaque sous CEC dans un seul établissement. Au total, 50 patients ont été randomisés à une gestion conventionnelle guidée par l'ACT et 50 à une gestion guidée par le système HMS Plus. Le critère d'évaluation principal était la variation de la génération de thrombine post-CEC par rapport aux valeurs de base, telles qu'évaluées par thrombographie calibrée automatisée. Les critères secondaires comprenaient les pertes sanguines peropératoires, le drainage thoracique jusqu'à 72 heures et les transfusions. Dans une analyze exploratoire, nous avons comparé le quintile de patients ayant la concentration moyenne d'héparine la plus élevée sous CEC (≥ 4,0 mg⋅kg-1) au reste de la cohorte. RéSULTATS: Au total, 100 patients ont été inclus dans une analyze en intention de traiter. Nous n'avons observé aucune différence dans la génération de thrombine post-CEC ou dans nos critères d'évaluation secondaires. Cependant, les patients du groupe HMS Plus présentaient des concentrations moyennes d'héparine plus élevées sous CEC que les patients du groupe de gestion conventionnelle (différence moyenne, -0,21; intervalle de confiance à 95 %, -0,42 à -0,01). Le quintile de patients ayant la concentration moyenne d'héparine la plus élevée (4,0 mg⋅kg-1) avaient une génération de thrombine post-CEC plus élevée que le reste de la cohorte. CONCLUSION: Le système HMS Plus n'a pas montré d'avantages significatifs dans la génération de thrombine, les issues hémorragiques ou la transfusion chez les patients bénéficiant d'une chirurgie cardiaque sous CEC. Des concentrations moyennes d'héparine plus élevées sous CEC ont été associées à une génération de thrombine post-CEC plus élevée. ENREGISTREMENT DE L'éTUDE: www.ClinicalTrials.gov (NCT03347201); soumis pour la première fois le 12 octobre 2017.

Albumin use for fluid resuscitation in cardiac surgical patients: a survey of Canadian perioperative care providers.

PURPOSE: To evaluate the perceptions and practices of Canadian cardiovascular anesthesiologists and intensivists towards intravenous albumin as a resuscitation fluid in patients undergoing cardiac surgery. METHODS: We conducted a cross-sectional survey of cardiac anesthesiologists and intensivists involved in the care of cardiac surgical patients. The 22-item survey included seven open-ended questions and assessed practice patterns and attitudes towards albumin. Descriptive statistics were analyzed using counts and proportions. Qualitative data were analyzed to identify themes describing albumin use patterns in Canada. RESULTS: A total of 133 respondents from seven provinces participated, with 83 (62%) using albumin perioperatively. The majority of respondents (77%) felt a low fluid balance in cardiac surgical patients was important, and that supplementing crystalloids with albumin was helpful for this objective (67%). There was poor agreement among survey respondents regarding the role of albumin for faster vasopressor weaning or intensive care discharge, and ≥ 90% did not feel albumin reduced mortality, renal injury, or coagulopathy. Nevertheless, cardiac surgical patients were identified as a distinct population where albumin may help to minimize fluid balance. There was an acknowledged paucity of formal evidence supporting possible benefits. Fewer than 10% of respondents could identify institutional or national guidelines for albumin use. A lack of evidence supporting albumin use in cardiac surgical patients, especially those at highest risk of complications, was a frequently identified concern. CONCLUSIONS: The majority of Canadian anesthesiologists and intensivists (62%) use albumin in cardiac surgical patients. There is clinical equipoise regarding its utility, and an acknowledged need for higher quality evidence to guide practice.

RéSUMé: OBJECTIF: Évaluer les perceptions et les pratiques des anesthésiologistes et intensivistes cardiovasculaires canadiens à l'égard de l'albumine intraveineuse comme liquide de réanimation pour les patients bénéficiant d'une chirurgie cardiaque. MéTHODE: Nous avons mené un sondage transversal auprès d'anesthésiologistes et d'intensivistes cardiaques impliqués dans les soins aux patients de chirurgie cardiaque. Le sondage en 22 éléments comprenait sept questions ouvertes et évaluait les habitudes de pratique et les attitudes des praticiens à l'égard de l'albumine. Les statistiques descriptives ont été analysées à l'aide de dénombrements et de proportions. Des données qualitatives ont été analysées pour identifier des thèmes décrivant les tendances d'utilisation de l'albumine au Canada. RéSULTATS: Au total, 133 répondants de sept provinces ont participé, et 83 (62 %) utilisent l'albumine en périopératoire. La majorité des répondants (77 %) estimaient qu'un bilan liquidien négatif était important chez les patients en chirurgie cardiaque et que la supplémentation en cristalloïdes par de l'albumine était utile pour atteindre cet objectif (67 %). Il y avait un faible accord parmi les répondants concernant le rôle de l'albumine pour accélérer le sevrage des vasopresseurs ou la sortie de soins intensifs, et ≥ 90 % ne pensaient pas que l'albumine réduisait la mortalité, les lésions rénales ou la coagulopathie. Néanmoins, les patients en chirurgie cardiaque ont été identifiés comme une population distincte pour laquelle l'albumine pourrait contribuer à minimiser le bilan liquidien. Il y avait un manque reconnu de données probantes formelles à l'appui des avantages possibles. Moins de 10 % des répondants ont pu trouver des lignes directrices institutionnelles ou nationales portant sur l'utilisation de l'albumine. Le manque de données probantes à l'appui de l'utilisation de l'albumine chez les patients en chirurgie cardiaque, en particulier chez ceux présentant le risque le plus élevé de complications, était une préoccupation fréquemment identifiée. CONCLUSION: La majorité des anesthésiologistes et intensivistes canadiens (62 %) utilisent l'albumine chez les patients en chirurgie cardiaque. Il existe un équilibre clinique quant à son utilité et un besoin reconnu de données probantes de meilleure qualité pour guider la pratique.

Outcomes of expanded polytetrafluoroethylene pericardial membrane implantation in left ventricular assist device explantation and heart transplantation.

OBJECTIVES: Redo sternotomy and explantation of left ventricular assist devices (LVAD) for heart transplantation (HT) involve prolonged dissection, potential injury to mediastinal structures and/or bleeding. Our study compared a complete expanded polytetrafluoroethylene (ePTFE) wrap versus minimal or no ePTFE during LVAD implantation, on outcomes of subsequent HT. METHODS: Between July 2005 and July 2018, 84 patients underwent a LVAD implant and later underwent HT. Thirty patients received a complete ePTFE wrap during LVAD implantation (Group 1), and 54 patients received either a sheet of ePTFE placed in the anterior mediastinum or no ePTFE (Group 2). RESULTS: Baseline characteristics were similar between Groups 1 and 2. Surgeons reported subjective improvements in speed, predictability, and safety of dissection with complete ePTFE compared with minimal or no ePTFE. Time from incision to initiation of cardiopulmonary bypass (CPB) were similar between groups (97 ± 38 vs. 89 ± 29 min, p = .3). Injury to mediastinal structures during the dissection was similar between groups (10% vs. 11%, p > .9). While surgeons reported less intraoperative bleeding in Group 1 (43% vs. 61%), this trend did not reach significance (p = .1). In-hospital mortality, intensive care unit length of stay and hospital length of stay were similar between both groups. CONCLUSIONS: In patients undergoing LVAD explant-HT, there was a trend toward reduced surgeon reported intraoperative bleeding with ePTFE placement. Despite qualitatively reported greater ease and speed of mediastinal dissection with ePTFE membrane placement, time to initiation of CPB did not differ, likely because surgeons remained cautious, allowing extra time for unanticipated difficulties.

Association between continuous-flow left ventricular assist device infections requiring long-term antibiotic use and post-heart transplant morbidity and mortality.

BACKGROUND AND AIM OF STUDY: There exists controversy regarding the impact of infection in patients with a left ventricular assist device (LVAD) on post-heart transplant outcomes. This study evaluated the association between infections during LVAD support and the risk of early and late post-heart transplant infection, rejection, and mortality in transplant recipients bridged with an LVAD. METHODS: This is a single-center retrospective observational cohort study of consecutive adults supported with a continuous flow LVAD undergoing heart transplant between 2006 and 2019 at the Toronto General Hospital. The grade of LVAD infection was classified as per International Society of Heart and Lung Transplantation guidelines. Patients were divided into three groups: (1) patients with LVAD-specific infection confirmed with positive cultures requiring long-term antibiotic use until the time of transplant; (2) patients with any type of infection in whom antibiotics were stopped at least 1 month before transplant; (3) patients without any infections between LVAD implant and transplant. Logistic regression and Cox proportional hazard models were used to evaluate early- and late-post transplant outcomes, respectively. RESULTS: We included 75 LVAD recipients: 16 (21%) patients had a chronic LVAD-related infection on suppressive antibiotics, 30 (40%) had a resolved infection, and 29 (39%) had no infections. During a median post-transplant follow-up time of 4 (2 to 7) years, 65 (87%) patients developed infections, 43 (64%) rejections, and 17 (23%) deaths. Both short- and long-term risks of infection, rejection, and mortality did not differ significantly among the groups. CONCLUSION: LVAD patients with infections did not have a significantly higher risk of infection, rejection, or mortality at any time point after transplant.