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In an attempt to replace the oncotic and protein coating capabilities of serum albumin in the perfusate, we established a priming protocol that used autologous blood as part of the perfusate solution. Prior to March 1, 1999, our standard priming protocol was 1650 ml of crystalloid with 250 ml of 5% serum albumin and 5000 units of heparin. After removing albumin from our prime, our standard protocol was altered to include 40 ml of the patient's autologous blood in 1800 ml of crystalloid and 10000 units of heparin. To determine the intraoperative effects of using albumin/crystalloid primes (Group A), autologous blood/crystalloid primes (Group B) and crystalloid primes (Group C), a total of 178 patients were sequentially evaluated. Intraoperative parameters evaluated were total protein (TP), colloid osmotic pressure (COP), platelets (Plts) and fluid requirements during cardiopulmonary bypass (CPB). During an overlapping 12-month period of time, 1092 consecutive cardiac surgical cases using CPB (584 albumin prime; 508 autologous blood prime) were evaluated for clinical outcomes in terms of mortality and length of hospitalization. In addition, over a period of 15 months, 1458 patients in both the autologous blood/crystalloid group and the crystalloid only group were evaluated for the incidence of high-pressure excursions (HPE) after going on bypass. Comparative reviews of TP, COP and Plts demonstrated no significant difference 10 min after the start of bypass between Groups A and B. However, in Group C, there was a statistically significant increase in the intraoperative fluid requirements during CPB, compared to both of the other groups. There was no significant difference in the incidence of HPE, with an occurrence of 1.04% in the crystalloid only group and 1.11% in the autologous blood/crystalloid group. Autologous blood perfusates were identical to albumin perfusates in their platelet protection and reduction of fluid shifts during the intraoperative period. [ABSTRACT FROM AUTHOR]

The coronavirus disease 2019 (COVID-19) pandemic continues to disrupt the provision of cardiac procedural services due to overwhelming interval surges in COVID-19 cases and the associated crisis of cardiac intervention deferment. Despite the availability of widespread testing, highly efficacious vaccines, and intensive public health efforts, the pandemic is entering its third year, where new severe acute respiratory syndrome-coronavirus-2 variants have increased the likelihood that patients scheduled for a cardiac intervention will contract COVID-19 in the perioperative period. The Society of Thoracic Surgeons (STS) Workforce on Critical Care, the STS Workforce on Adult Cardiac and Vascular Surgery, and the Canadian Society of Cardiac Surgeons have developed this document, endorsed by the STS and affirmed by the Society of Cardiovascular Angiography and Interventions and the Canadian Association of Interventional Cardiology, to provide guidance for cardiac procedure deferment and intervention timing for preoperative patients diagnosed with COVID-19. This document is intended for the perioperative cardiac surgical team and outlines the present state of the pandemic, the impact of COVID-19 on intervention outcome, and offers a recommended algorithm for individualized cardiac procedure triage and timing., (Copyright © 2022 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.)

Background: Transvenous lead extraction can have serious adverse events, such as cardiac or vascular perforation. Risk factors have not been well characterized., Objective: The purpose of this study was to identify factors associated with perforation and death, and to characterize lead extraction in a large contemporary population., Methods: We performed a retrospective multicenter study examining patients undergoing lead extraction at 8 Canadian institutions from 1996 through 2016. Demographic and clinical data were used to identify variables associated with perforation and mortality using logistic regression modeling., Results: A total of 2325 consecutive patients (age 61.9 ±16.5 years) underwent extraction of 4527 leads. Perforation rate was 2.7% (63/2325) and 30-day mortality was 1.6% (38/2325), with mortality of 0.4% due to perforation (10/2325). Variables associated with perforation included no previous cardiac surgery (odds ratio [OR] 3.33; 95% confidence interval [CI] 1.54-7.19; P = .002), female sex (OR 3.27; 95% CI 1.91-5.60; P <.001); left ventricular ejection fraction ≥40% (OR 2.81; 95% CI 1.28-6.14; P = .010); lead age >8 years (OR 2.64; 95% CI 1.52-4.60; P <.001); ≥2 leads extracted (OR 2.49; 95% CI 1.23-5.04; P = .011); and diabetes (OR 2.12; 95% CI 1.16-3.86; P = .014). Variables associated with death included infection as indication for extraction (OR 3.85; 95% CI 1.38-10.73; P = .010); anemia (OR 3.14; 95% CI 1.38-6.61; P = .003), and patient age (OR 1.04; 95% CI 1.01-1.07; P = .012)., Conclusion: Risk factors associated with perforation in lead extraction include no history of cardiac surgery, female sex, preserved left ventricular ejection fraction, lead age >8 years, ≥2 leads extracted, and diabetes., (Copyright © 2021. Published by Elsevier Inc.)

Aim: Monitoring minimal residual disease remains a challenge to the effective medical management of hematological malignancies; yet surface-enhanced Raman spectroscopy (SERS) has emerged as a potential clinical tool to do so. Materials & methods: We developed a cell-free, label-free SERS approach using gold nanoparticles (nanoSERS) to classify hematological malignancies referenced against two control cohorts: healthy and noncancer cardiovascular disease. A predictive model was built using machine-learning algorithms to incorporate disease burden scores for patients under standard treatment upon. Results: Linear- and quadratic-discriminant analysis distinguished three cohorts with 69.8 and 71.4% accuracies, respectively. A predictive nanoSERS model correlated (MSE = 1.6) with established clinical parameters. Conclusion: This study offers a proof-of-concept for the noninvasive monitoring of disease progression, highlighting the potential to incorporate nanoSERS into translational medicine.

Background: The coronavirus disease 2019 (COVID-19) pandemic has had an unprecedented impact on health care and cardiac surgery. We report cardiac surgeons' concerns, perceptions, and responses during the COVID-19 pandemic., Methods: A detailed survey was sent to recruit participating adult cardiac surgery centers in North America. Data regarding cardiac surgeons' perceptions and changes in practice were analyzed., Results: Our study comprises 67 institutions with diverse geographic distribution across North America. Nurses were most likely to be redeployed (88%), followed by advanced care practitioners (69%), trainees (28%), and surgeons (25%). Examining surgeon concerns in regard to COVID-19, they were most worried with exposing their family to COVID-19 (81%), followed by contracting COVID-19 (68%), running out of personal protective equipment (PPE) (28%), and hospital resources (28%). In terms of PPE conservation strategies among users of N95 respirators, nearly half were recycling via decontamination with ultraviolet light (49%), followed by sterilization with heat (13%) and at home or with other modalities (13%). Reuse of N95 respirators for 1 day (22%), 1 week (21%) or 1 month (6%) was reported. There were differences in adoption of methods to conserve N95 respirators based on institutional pandemic phase and COVID-19 burden, with higher COVID-19 burden institutions more likely to resort to PPE conservation strategies., Conclusions: The present study demonstrates the impact of COVID-19 on North American cardiac surgeons. Our study should stimulate further discussions to identify optimal solutions to improve workforce preparedness for subsequent surges, as well as facilitate the navigation of future healthcare crises., (© 2021 Wiley Periodicals LLC.)

Background: Current intensive care unit physician-staffing (IPS) models for postoperative cardiac surgery have not been previously investigated in Canada. The purpose of this study was to determine current IPS models at 2 time points and describe the evolution of Canadian cardiac surgery IPS models., Methods: A survey of 32 Canadian cardiovascular intensive care units (CVICUs) was undertaken in 2012 and 2017 to determine IPS models of care during "daytime" and "after-hours" in each unit. Data were collected regarding surgical volume, base specialties, and style of IPS management ("open"; "semi-open"; "closed"). In addition, we collected the overnight experience level of the bedside healthcare provider for in-house intensive care units., Results: Survey responses were received from 27 of 32 CVICUs (87%). As of 2017, the style of 1 (4%) was open, 7 (26%) were semi-open, and 19 (70%) were closed in their unit IPS strategy. Base specialties of CVICU physicians varied. A medical doctor provided after-hours coverage in 81% of CVICUs. Senior residents (37%) or critical care certified attending staff (25%) typically provided after-hours coverage for in-house CVICUs. Linked Canadian Institute for Health Information data did not indicate a difference among CVICU models in mortality or rehospitalization for coronary artery bypass graft or valve procedures., Conclusions: Considerable heterogeneity is demonstrated in CVICU staffing patterns. No consensus was identified regarding the appropriate level of training for "after-hours" coverage. In-house overnight physician staffing in CVICUs varies widely. Finally, semi-open and closed style models did not demonstrate differences compared to Canadian Institute for Health Information data. Variability among CVICUs does exist; however, benefits of one model over another have not been identified., (© 2021 The Authors.)

Background: Predicting relapses of post-operative complications in obese patients who undergo cardiac surgery is significantly complicated by persistent metabolic maladaptation associated with obesity. Despite studies supporting the linkages of increased systemic branched-chain amino acids (BCAAs) driving the pathogenesis of obesity, metabolome wide studies have either supported or challenged association of circulating BCAAs with cardiovascular diseases (CVDs). Objective: We interrogated whether BCAA catabolic changes precipitated by obesity in the heart and adipose tissue can be reliable prognosticators of adverse outcomes following cardiac surgery. Our study specifically clarified the correlation between BCAA catabolizing enzymes, cellular BCAAs and branched-chain keto acids (BCKAs) with the severity of cardiometabolic outcomes in obese patients pre and post cardiac surgery. Methods: Male and female patients of ages between 44 and 75 were stratified across different body mass index (BMI) (non-obese = 17, pre-obese = 19, obese class I = 14, class II = 17, class III = 12) and blood, atrial appendage (AA), and subcutaneous adipose tissue (SAT) collected during cardiac surgery. Plasma and intracellular BCAAs and BC ketoacids (BCKAs), tissue mRNA and protein expression and activity of BCAA catabolizing enzymes were assessed and correlated with clinical parameters. Results: Intramyocellular, but not systemic, BCAAs increased with BMI in cardiac surgery patients. In SAT, from class III obese patients, mRNA and protein expression of BCAA catabolic enzymes and BCKA dehydrogenase (BCKDH) enzyme activity was decreased. Within AA, a concomitant increase in mRNA levels of BCAA metabolizing enzymes was observed, independent of changes in BCKDH protein expression or activity. BMI, indices of tissue dysfunction and duration of hospital stay following surgery correlated with BCAA metabolizing enzyme expression and metabolite levels in AA and SAT. Conclusion: This study proposes that in a setting of obesity, dysregulated BCAA catabolism could be an effective surrogate to determine cardiac surgery outcomes and plausibly predict premature re-hospitalization., (Copyright © 2020 Biswas, Tozer, Dao, Perez, Mercer, Brown, Hossain, Yip, Aguiar, Motawea, Brunt, Shea, Legare, Hassan, Kienesberger and Pulinilkunnil.)

In the setting of the current novel coronavirus pandemic, this document has been generated to provide guiding statements for the adult cardiac surgeon to consider in a rapidly evolving national landscape. Acknowledging the risk for a potentially prolonged need for cardiac surgery procedure deferral, we have created this proposed template for physicians and interdisciplinary teams to consider in protecting their patients, institution, and their highly specialized cardiac surgery team. In addition, recommendations on the transition from traditional in-person patient assessments and outpatient follow-up are provided. Lastly, we advocate that cardiac surgeons must continue to serve as leaders, experts, and relevant members of our medical community, shifting our role as necessary in this time of need., (Copyright © 2020 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.)

The COVID-19 pandemic necessitates aggressive infection mitigation strategies to reduce the risk to patients and healthcare providers. This document is intended to provide a framework for the adult cardiac surgeon to consider in this rapidly changing environment. Preoperative, intraoperative, and postoperative detailed protective measures are outlined. These are guidance recommendations during a pandemic surge to be used for all patients while local COVID-19 disease burden remains elevated., (Copyright © 2020 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.)

The coronavirus disease 2019 (COVID-19) pandemic has had a profound global impact. Its rapid transmissibility has transformed healthcare delivery and forced countries to adopt strict measures to contain its spread. The vast majority of the United States cardiac surgical programs have deferred all but truly emergent/urgent operative procedures in an effort to reduce the burden on the healthcare system and to mobilize resources to combat the pandemic surge. While the number of COVID-19 cases continue to increase worldwide, the incidence of new cases has begun to decline in many North American cities. This "flattening of the curve" has prompted interest in reopening the economy, relaxing public health restrictions, and resuming nonurgent healthcare delivery. The following document provides a template whereby adult cardiac surgical programs may begin to ramp-up the care delivery in a deliberate and graded fashion as the COVID-19 pandemic burden begins to ease. "Resuscitating" the timely delivery of care is guided by three principles: (1) Collaborate to permit increased case volumes, balancing the clinical needs of patients awaiting surgical procedures with the local resources available within each healthcare system. (2) Prioritize patients awaiting elective procedures while proactively engaging all stakeholders, focusing on those with high-risk anatomy, changing/symptomatic clinical status, and, once these variables have been addressed, prioritizing by waiting times. (3) Reevaluate local conditions continuously to assess for any increase in admissions due to a recrudescence of cases, to assure adequate resources to care for patients, and to monitor in-hospital infectious transmissions to both patients and healthcare workers., (Copyright © 2020 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.)

Background: Perioperative blood loss is a major contributor to morbidity and mortality in cardiac surgery. Plasma fibrinogen levels play an essential role in hemostasis and deplete quickly during hemorrhage. The objective of this study was to determine whether prophylactic fibrinogen concentrate administration lowers overall blood product transfusion requirements in high-risk cardiac surgery in patients with low fibrinogen plasma levels., Methods: The study was performed in a prospective, randomized, and double-blinded design. The investigation included 62 patients undergoing elective, high-risk cardiac surgery. After weaning from cardiopulmonary bypass and reversal of heparin patients received either fibrinogen concentrate or placebo. The primary outcome variable was overall blood product usage 24 hours after intervention., Results: The fibrinogen group received numerically fewer total units of blood products than the placebo group, but the difference was not statistically or clinically significant (for groups n = 27; n = 29 and 19 vs 37 units, respectively, P = .908). The overall transfusion rate in both groups was significantly lower than the institutional average suggested (fibrinogen group 26%, placebo group 28%). The fibrinogen group showed significantly higher fibrinogen levels (2.38 vs 1.83 g/L (end of surgery), P < .001; 3.33 vs 2.68 g/L (12 hours after intervention), P = .003) and improved viscoelastic coagulation parameters (FIBTEM MCF, 27 vs 23 mm, P = .022)., Conclusion: This randomized, controlled trial demonstrates that point-of-care guided and prophylactic treatment with fibrinogen concentrate does not reduce transfusion of blood products in a setting of unexpectedly low transfusion rate as tested in this cohort, but may improve coagulation parameters in the setting of high-risk cardiac surgery., (© 2019 The Acta Anaesthesiologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.)

Background: The objectives of the study were to characterize and quantify cellular inflammation and structural remodeling of human atria and correlate findings with molecular markers of inflammation and patient surrogate outcome., Methods: Voluntary participants undergoing heart surgery were enrolled in the study and blood samples were collected prior to surgery, and right atrium samples were harvested intraoperatively. Blood samples were analyzed by flow cytometry and complete blood counts. Atrial samples were divided for fixed fibrosis analysis, homogenized for cytokine analysis and digested for single cell suspension flow cytometry., Results: A total of 18 patients were enrolled and samples assessed. Isolated cells from the atria revealed a CD45+ population of ~ 20%, confirming a large number of leukocytes. Further characterization revealed this population as 57% lymphocytes and 26% monocyte/macrophages (MoΦ), with the majority of the latter cells being classical (CD14++/CD16-). Interstitial fibrosis was present in 87% of samples and correlated significantly with patient age. Older patients (> 65) had significantly more atrial fibrosis and cellular inflammation. AFib patients had no distinguishing feature of atrial fibrosis and had significantly greater CD45+ MoΦ, increased expression of MMP9 and presented with a significant correlation in length of stay to CCL-2/MCP-1 and NLR (neutrophil-to-lymphocyte ratio)., Conclusion: Atrial fibrosis is correlated with age and not determinate to AFib. However, severity of atrial leukocyte infiltration and markers of matrix degradation are determinant to AFib. This also correlated with CCL2 (or MCP-1) and NLR-indicative of marked inflammation. These data show the potential importance of diagnostic and prognostic assessments that could inform clinical decision making in regard to the intensity of AFib patient management.

Background: Lysophosphatidic acid (LPA) receptor signaling has been implicated in cardiovascular and obesity-related metabolic disease. However, the distribution and regulation of LPA receptors in the myocardium and adipose tissue remain unclear., Objectives: This study aimed to characterize the mRNA expression of LPA receptors (LPA1-6) in the murine and human myocardium and adipose tissue, and its regulation in response to obesity., Methods: LPA receptor mRNA levels were determined by qPCR in i) heart ventricles, isolated cardiomyocytes, and perigonadal adipose tissue from chow or high fat-high sucrose (HFHS)-fed male C57BL/6 mice, ii) 3T3-L1 adipocytes and HL-1 cardiomyocytes under conditions mimicking gluco/lipotoxicity, and iii) human atrial and subcutaneous adipose tissue from non-obese, pre-obese, and obese cardiac surgery patients., Results: LPA1-6 were expressed in myocardium and white adipose tissue from mice and humans, except for LPA3, which was undetectable in murine adipocytes and human adipose tissue. Obesity was associated with increased LPA4, LPA5 and/or LPA6 levels in mice ventricles and cardiomyocytes, HL-1 cells exposed to high palmitate, and human atrial tissue. LPA4 and LPA5 mRNA levels in human atrial tissue correlated with measures of obesity. LPA5 mRNA levels were increased in HFHS-fed mice and insulin resistant adipocytes, yet were reduced in adipose tissue from obese patients. LPA4, LPA5, and LPA6 mRNA levels in human adipose tissue were negatively associated with measures of obesity and cardiac surgery outcomes. This study suggests that obesity leads to marked changes in LPA receptor expression in the murine and human heart and white adipose tissue that may alter LPA receptor signaling during obesity.

The global incidence of obesity has led to an increasing need for understanding the molecular mechanisms that drive this epidemic and its comorbidities. Quantitative real-time RT-PCR (RT-qPCR) is the most reliable and widely used method for gene expression analysis. The selection of suitable reference genes (RGs) is critical for obtaining accurate gene expression information. The current study aimed to identify optimal RGs to perform quantitative transcriptomic analysis based on RT-qPCR for obesity and diabetes research, employing in vitro and mouse models, and human tissue samples. Using the ReFinder program we evaluated the stability of a total of 15 RGs. The impact of choosing the most suitable RGs versus less suitable RGs on RT-qPCR results was assessed. Optimal RGs differed between tissue and cell type, species, and experimental conditions. By employing different sets of RGs to normalize the mRNA expression of peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC1α), we show that sub-optimal RGs can markedly alter the PGC1α gene expression profile. Our study demonstrates the importance of validating RGs prior to normalizing transcriptional expression levels of target genes and identifies optimal RG pairs for reliable RT-qPCR normalization in cells and in human and murine muscle and adipose tissue for obesity/diabetes research.

Purpose: Serum troponin (cTnT) levels, a commonly measured biomarker of myocardial injury, has rarely been considered in risk models after cardiac surgery., Materials and Methods: Retrospective study of patients undergoing any cardiac surgery between 2004 and 2012. Patients with a history of recent myocardial injury (<21 days) were excluded. The minimum P value approach was used to determine categories of peak cTnT associated with in-hospital death. A multivariable analysis was performed to identify independent predictors of mortality., Results: A total of 5318 patients without evidence of preoperative ischemia underwent a number of cardiac surgical interventions ranging from isolated coronary revascularization to combined valve coronary artery bypass grafting. The unadjusted in-hospital mortality rate was 3.3% (n = 175 patients). Four categories of peak cTnT were identified using the minimum P value approach: less than or equal to 0.6 ng/mL, 0.7 to 1.9 ng/mL, 2.0 to 3.1 ng/mL, and greater than 3.1 ng/mL with unadjusted mortality rates of 1.0%, 3.6%, 10.1%, and 33.1%, respectively. Multivariate logistic regression demonstrated that all peak cTnT levels greater than 0.6 ng/mL were independent predictors of in-hospital mortality in a dose-dependent manner., Conclusions: We demonstrate that in patients without preoperative myocardial ischemia, the demonstration of myocardial injury (>0.6 ng/mL) in the postoperative period is highly predictive of in-hospital death., (Copyright © 2016 Elsevier Inc. All rights reserved.)

Background: The characteristics of circulating inflammatory cells (leukocytes) in patients undergoing heart surgery remains poorly understood. Recently, neutrophil-to-lymphocyte ratio (NLR) and specific monocyte subsets (based on CD14/CD16 expression) have been suggested as markers of inflammation and predictors of outcomes. The present study aims to characterize the influence cardiac surgery with cardiopulmonary bypass has on specific circulating leukocytes., Methods: All enrolled patients had blood samples taken pre- (0 days), early post- (5 days), and late post- (90 days) surgery. Complete blood counts were performed and whole leukocyte isolations were obtained from blood samples and analyzed with flow cytometry. Fluorophore-linked antibodies (CD45, CD11b, CD14, and CD16) were added to the blood cell isolations and later assessed by flow cytometry., Results: Seventeen patients were enrolled and samples obtained at 0, 5, and 90 days. We demonstrated a significant increase in NLR (2.2-fold; p  = 0.0028) and CD16 mean fluorescence index (MFI-measure fluorescence intensity shift of CD16 in a gated cell population) early at day 5 (2.0-fold; p  = 0.0051). Both NLR and CD16 MFI levels generally returned to normal by day 90. There was a significant positive correlation between NLR and CD16 MFI ( r 2 = 0.29; p  = 0.0064). Adverse cardiovascular event (AE) was defined as prolonged length of hospitalization or readmission to hospital for cardiac reasons after discharge was seen in 59% of patients (no deaths occurred). In an unadjusted analysis of AE, we identified NLR as a likely predictor of AE, which meant that patients developing AE had a significantly higher baseline NLR ( p  = 0.0065), something that was not observed with CD16 MFI ( p  = 0.2541)., Conclusion: Cardiac surgery is associated with a significant increase in NLR and CD16 MFI (non-classical monocytes) early after surgery corresponding to the early inflammatory phase after surgery. Furthermore, we have, for the first time, identified a significant correlation between NLR and CD16 MFI. While the mechanism for this relationship remains unclear, our findings support the use of a simple test of NLR as a biomarker of inflammation for predicting outcomes in cardiac surgery patients.

Background: The management of hospital-acquired infections (HAIs) with respect to physician practices remains largely unexplored despite increasing efforts to standardize care. In the present study, we report findings from a 2-month audit of all patients that have undergone cardiac surgery at a large referral center in Atlantic Canada., Methods: All patients who underwent cardiac surgical procedures during May and June 2013 at the Queen Elizabeth II Health Sciences Center in Halifax, Nova Scotia were identified. The prevalence of urinary tract infections (UTIs), pneumonia, leg harvest site infections, superficial sternal wound infections, deep sternal wound infections, and sepsis was examined to determine physician approaches in terms of verification rates (microbiology), time of diagnosis and duration of treatment. Continuous variables were compared using Student's t -test and categorical variables were analyzed using Fischer's exact test., Results: A total of 185 consecutive patients underwent cardiac surgical procedures, of which 39 (21%) developed at least one postoperative infection. The overall prevalence of infection types, from highest to lowest, was UTI (8%), pneumonia (7%), leg harvest site infection (5%), superficial surgical site infection (4%), and sepsis (2%). There were no deep sternal wound infections. The overall in-hospital mortality rate was 3.8% with a median length of stay (LOS) of 8 days. The overall infection verification rate was 50% (ranged from 100% in sepsis to 10% in leg harvest site infections). In all cases, a full course of antibiotics was administered despite negative microbiology cultures or limited evidence of an actual infection., Conclusions: HAIs are commonly treated without being verified and treatment is often not discontinued after negative cultures are received. Our findings highlight the fact that antibiotic treatment is not always supported by evidence, and the effect of this could contribute to increased selective pressure for antimicrobial resistant bacteria.

Impaired cardiac metabolism in the obese and diabetic heart leads to glucolipotoxicity and ensuing cardiomyopathy. Glucolipotoxicity causes cardiomyocyte injury by increasing energy insufficiency, impairing proteasomal-mediated protein degradation and inducing apoptosis. Proteasome-evading proteins are degraded by autophagy in the lysosome, whose metabolism and function are regulated by master regulator transcription factor EB (TFEB). Limited studies have examined the impact of glucolipotoxicity on intra-lysosomal signaling proteins and their regulators. By utilizing a mouse model of diet-induced obesity, type-1 diabetes (Akita) and ex-vivo model of glucolipotoxicity (H9C2 cells and NRCM, neonatal rat cardiomyocyte), we examined whether glucolipotoxicity negatively targets TFEB and lysosomal proteins to dysregulate autophagy and cause cardiac injury. Despite differential effects of obesity and diabetes on LC3B-II, expression of proteins facilitating autophagosomal clearance such as TFEB, LAMP-2A, Hsc70 and Hsp90 were decreased in the obese and diabetic heart. In-vivo data was recapitulated in H9C2 and NRCM cells, which exhibited impaired autophagic flux and reduced TFEB content when exposed to a glucolipotoxic milieu. Notably, overloading myocytes with a saturated fatty acid (palmitate) but not an unsaturated fatty acid (oleate) depleted cellular TFEB and suppressed autophagy, suggesting a fatty acid specific regulation of TFEB and autophagy in the cardiomyocyte. The effect of glucolipotoxicity to reduce TFEB content was also confirmed in heart tissue from patients with Class-I obesity. Therefore, during glucolipotoxicity, suppression of lysosomal autophagy was associated with reduced lysosomal content, decreased cathepsin-B activity and diminished cellular TFEB content likely rendering myocytes susceptible to cardiac injury., (Copyright © 2016 Elsevier B.V. All rights reserved.)

Background: Macrophages (MΦ) are functionally diverse and dynamic. Until recently, cardiac MΦ were assumed to be monocyte derived; however, resident cardiac MΦ (rCMΦ), present at baseline, were identified in myocardia and have been implicated in cardiac healing. Previously, we demonstrated that CCR2(-/-) mice are protected from myocardial fibrosis - an observation initially attributed to changes in infiltrating monocytes. Here, we reexplored this observation in the context of our new understanding of rCMΦ., Methods: Male CCR2(-/-) and C57BL/6 hearts were digested and purified to a single cell suspension, incubated with fluorophore-linked antibodies (CCR2, CX3CR1, CD11b, Ly6C, TNF-α, and IL-10), and assessed by flow cytometry. Differentiated MΦ were cocultured with fibroblasts in order to characterize how MΦ phenotype influences fibroblast activation. Fibroblasts were characterized for their expression of smooth muscle cell actin (SMA)., Results: A significant decrease in Ly6C expression was observed in the CCR2(-/-) cardiac MΦ population relative to WT, which corresponded with significantly lower TNF-α expression and significantly higher IL-10 expression. Using in vitro coculture system, classical MΦ promoted fibroblast activation relative to nonclassical MΦ., Conclusion: CCR2(-/-) rCMΦ favor a more antiinflammatory phenotype relative to WT controls. Moreover, a shift toward the antiinflammatory promotes proliferation, but not activation in vitro. Together, these observations suggest that antiinflammatory cardiac MΦ populations may inhibit myocardial fibrosis in a pathological setting by preventing the activation of fibroblasts., News and Noteworthy: Here, we provide novel evidence for baseline differences in rCMΦ phenotypes (i.e. classical vs. nonclassical) and how these differences could modulate cardiac healing. Importantly, we observed differences in how classical vs. nonclassical MΦ influenced fibroblast activation, which could, in turn, affect fibrosis., (Copyright © 2016 Elsevier Inc. All rights reserved.)

Objective: This study sought to evaluate if the presence of endocarditis was independently associated with increased perioperative blood transfusion in patients undergoing aortic valve replacements (AVR) with aortic regurgitation., Design: This was a retrospective study., Setting: Large Canadian tertiary care hospital., Participants: Six hundred sixty-two consecutive patients with aortic regurgitation score of 3 or higher undergoing AVR from 1995 to 2012., Interventions: No interventions were performed in this retrospective study., Measurements and Main Results: After REB approval, data were obtained from a center-specific database. Univariate analysis was performed to identify variables that may be associated with transfusion of any allogeneic blood product perioperatively. A multivariate logistic regression was generated to identify independent predictors of perioperative transfusion. Unadjusted transfusion rates in patients with no endocarditis and with endocarditis were 32% and 70% (p<0.001), respectively. Independent predictors of any transfusion were moderate-to-severe preoperative anemia, preoperative renal failure, non-isolated AVR, age>70, urgent/emergent surgery, BMI<25, and female sex. Endocarditis was not an independent predictor of transfusion (OR = 0.748; 95% CI = 0.35-1.601)., Conclusions: In patients undergoing AVR, unadjusted perioperative transfusion rates were higher when endocarditis was present. However, after adjustment, aortic valve endocarditis was not independently associated with blood transfusion. The authors' observation could be explained by the higher prevalence of many independent predictors of transfusion, such as comorbidities or more complex surgery, within the endocarditis group. Thus, AV endocarditis, in the absence of other risk factors, was not associated with increased perioperative transfusion risk., (Copyright © 2016 Elsevier Inc. All rights reserved.)

Background: Persistent incisional pain is common after cardiac surgery and is believed to be in part related to inflammation and poorly controlled acute pain. Methylprednisolone is a corticosteroid with substantial antiinflammatory and analgesic properties and is thus likely to ameliorate persistent surgical pain. Therefore, the authors tested the primary hypothesis that patients randomized to methylprednisolone have less persistent incisional pain than those given placebo., Methods: One thousand forty-three patients having cardiopulmonary bypass for cardiac surgery via a median sternotomy were included in this substudy of Steroids in Cardiac Surgery (SIRS) trial. Patients were randomized to 500 mg intraoperative methylprednisolone or placebo. Incisional pain was assessed at 30 days and 6 months after surgery, and the potential risk factors were also evaluated., Results: Methylprednisolone administration did not reduce pain at 30 days or persistent incisional pain at 6 months, which occurred in 78 of 520 patients (15.7%) in the methylprednisolone group and in 88 of 523 patients (17.8%) in the placebo group. The odds ratio for methylprednisolone was 0.93 (95% CI, 0.79 to 1.09, P = 0.37). Furthermore, there was no difference in worst pain and average pain in the last 24 h, pain interference with daily life, or use of pain medicine at 6 months. Younger age, female sex, and surgical infections were associated with the development of persistent incisional pain., Conclusions: Intraoperative methylprednisolone administration does not reduce persistent incisional pain at 6 months in patients recovering from cardiac surgery.

Background: Atrial natriuretic peptide (ANP) is a hormone with numerous beneficial cardiovascular effects. Recently, a mutation in the ANP gene, which results in the generation of a mutant form of ANP (mANP), was identified and shown to cause atrial fibrillation in people. The mechanism(s) through which mANP causes atrial fibrillation is unknown. Our objective was to compare the effects of wild-type ANP and mANP on atrial electrophysiology in mice and humans., Methods and Results: Action potentials (APs), L-type Ca(2+) currents (ICa,L), and Na(+) current were recorded in atrial myocytes from wild-type or natriuretic peptide receptor C knockout (NPR-C(-/-)) mice. In mice, ANP and mANP (10-100 nmol/L) had opposing effects on atrial myocyte AP morphology and ICa,L. ANP increased AP upstroke velocity (Vmax), AP duration, and ICa,L similarly in wild-type and NPR-C(-/-) myocytes. In contrast, mANP decreased Vmax, AP duration, and ICa,L, and these effects were completely absent in NPR-C(-/-) myocytes. ANP and mANP also had opposing effects on ICa,L in human atrial myocytes. In contrast, neither ANP nor mANP had any effect on Na(+) current in mouse atrial myocytes. Optical mapping studies in mice demonstrate that ANP sped electric conduction in the atria, whereas mANP did the opposite and slowed atrial conduction. Atrial pacing in the presence of mANP induced arrhythmias in 62.5% of hearts, whereas treatment with ANP completely prevented the occurrence of arrhythmias., Conclusions: These findings provide mechanistic insight into how mANP causes atrial fibrillation and demonstrate that wild-type ANP is antiarrhythmic., (© 2015 American Heart Association, Inc.)

Objective: To date only a few randomized controlled studies have compared grafting strategies in patients with multi-vessel coronary disease. This study represents a pilot RCT designed to test the feasibility of a trial comparing conventional CABG performed with a LIMA-LAD plus saphenous vein grafts (LIMA+SVG) and CABG performed with total arterial grafting (TAG)., Methods: Consenting patients undergoing non-redo isolated CABG surgery at a single institution were randomized to TAG or LIMA+SVG groups. Exclusion criteria included prior CABG, emergent procedure, concomitant procedure, varicose veins and renal dysfunction. The primary endpoints were: enrolment >20% and completion of CT coronary angiography at 6 months >80%. Statistical investigation was performed on an intention to treat analysis., Results: Of 421 eligible patients, 60 were enrolled and 2 withdrew (n = 30 in TAG, n = 28 LIMA+SVG) for 14% enrolment rate. Patient characteristics were similar in each group. No patients died in hospital and adverse events such as MI, stroke and deep sternal wound infection were not significantly different between groups. Clinical follow-up was complete in 100% of patients, with 44/58 (76%) undergoing CT coronary angio at 6 months. Graft occlusion occurred in 2 patients in each group for patency rates of 89% (TAG) and 91% (LIMA+SVG)., Conclusions: We provide evidence that an RCT comparing grafting strategy is possible but also show that achieving recruitment or follow-up CT may be difficult. Given the excellent patency results and little difference between groups, our findings suggest that the sample size required may make it infeasible to compare graft patency at 6 months as a study end-point., Trial Registration: Randomized Controlled Trial number: ISRCTN80270323 . Few RCT's exist comparing conventional CABG performed with a LIMA-LAD plus saphenous vein grafts (LIMA+SVG) compared to CABG performed with total arterial grafting (TAG). This study is a pilot RCT designed to test the feasibility of such a trial and identify pitfalls.

Background: The HeartWare left ventricular assist device (HVAD; HeartWare Inc, Framingham, MA) was first implanted in Canada in 2010. We performed a multicentre analysis of the real world outcomes associated with its use., Methods: Between May 2010 and January 2013, 4 Canadian centres inserted a total of 72 HVADs in 71 patients. Data were collected prospectively and analyzed retrospectively for the 1-year estimate of the principal outcome of transplant, explant for recovery, or death in patients who had a bridge to transplantation indication. Adverse event rates were estimated as events per patient-year (PPY)., Results: In the 67 patients who received the HVAD with the indication of bridge to transplant, 26 (38.8%) received a successful transplant, 2 (3%) received an explant for recovery, and 10 (14.9%) patients died during support. Median follow-up time with the HVAD was 6.9 months (range, 2 days to 30.4 months). Despite having 74% of the patients with Interagency Registry for Mechanically Assisted Circulatory Support (INTERMACS) scores of level 1 and 2 at the time of implantation, the rate estimate for survival at 1 year was 86.3% (95% confidence interval, 76.7-93.3). With 48.2 total patient years of support, the rates of ischemic and hemorrhagic strokes were 0.21 and 0.19 events PPY, respectively. Women made up 40% of the cohort and an adverse neurologic event occurred with an event rate of 0.38 PPY in women., Conclusions: The HVAD adequately supports acutely ill heart failure patients until the time of transplant or recovery. A high incidence of adverse neurologic outcomes might be related to the large percentage of female patients, the high INTERMACS levels, or unknown factors; further surveillance is required., (Copyright © 2014 Canadian Cardiovascular Society. Published by Elsevier Inc. All rights reserved.)

Background: Advances in cardiac surgical care have allowed for successful surgery in high-risk elderly patients. Advances in percutaneous coronary intervention (PCI) techniques and expanded indications for PCI have resulted in a decrease in referrals for coronary artery bypass grafting (CABG). Our objective was to document changes in practice patterns and outcomes in a single tertiary cardiac surgery centre serving a large geographic area., Methods: For all cardiac surgery cases performed from 2001-2010 we examined its use, patient clinical characteristics, and outcomes. Frailty was assessed using a measure we have previously demonstrated to be associated with adverse outcomes., Results: During the study period, annual case volume decreased by 13%. The number of isolated CABG cases declined, and valve surgery and other complex procedures increased. The proportion of patients aged ≥ 80 years rose from 7%-12%, and the proportion of frail patients increased from 4%-10%. Although unadjusted in-hospital mortality remained relatively unchanged, intensive care unit (ICU) stays and prolonged institutional care increased. Older age and frailty were associated with mortality, prolonged ICU stays, prolonged institutional care, and a composite of mortality and major morbidities., Conclusions: Our findings showed a decline in CABG, an increase in more complex operations, and an increase in prolonged ICU stays and prolonged institutional care. The proportion of frail and elderly patients increased over time and these patient groups were at higher risk of adverse postoperative outcomes. Particular attention is required in the decision for surgery and perioperative management of these patients., (Copyright © 2014 Canadian Cardiovascular Society. Published by Elsevier Inc. All rights reserved.)

Background: Occlusion of the left atrial appendage (LAA) is a promising approach to stroke prevention in atrial fibrillation (AF). However, evidence of its efficacy and safety to date is lacking. We herein describe the rationale and design of a definitive LAA occlusion trial in cardiac surgical patients with AF., Methods: We plan to randomize 4,700 patients with AF in whom on-pump cardiac surgical procedure is planned to undergo LAA occlusion or no LAA occlusion. The primary outcome is the first occurrence of stroke or systemic arterial embolism over a mean follow-up of four years. Other outcomes include total mortality, operative safety outcomes (chest tube output in the first post-operative 24 hours, rate of post-operative re-exploration for bleeding in the first 48 hours post-surgery and 30-day mortality), re-hospitalization for heart failure, major bleed, and myocardial infarction., Results: Left Atrial Appendage Occlusion Study (LAAOS) III is funded in a vanguard phase by the Canadian Institutes for Health Research (CIHR), the Canadian Network and Centre for Trials Internationally, and the McMaster University Surgical Associates. As of September 9, 2013, 162 patients have been recruited into the study., Conclusions: LAAOS III will be the largest trial to explore the efficacy of LAA occlusion for stroke prevention. Its results will lead to a better understanding of stroke in AF and the safety and efficacy of surgical LAA occlusion.

The principal characteristic of arrhythmogenic right ventricular cardiomyopathy (ARVC) is the tendency for ventricular arrhythmia and sudden death to occur without overt ventricular dysfunction. Current recommendations for management of patients with ARVC include insertion of an automated implantable cardioverter-defibrillator (AICD) to prevent sudden cardiac death. However, despite the use of AICD and/or anti-arrhythmic drugs some patients suffer recurrent ventricular arrhythmias unresponsive to optimum medical management. We present two cases of ARVC with refractory recurrent ventricular arrhythmias that were successfully managed by left ventricular assist device (LVAD) implantation, as a bridge to transplant (BTT). These two cases are unconventional examples of use of LVAD, given the predominant right ventricular pathology of ARVC and the arrhythmogenic nature of their presentation. The novelty of these cases should be taken in the context of increasing pressure to standardize indications for use of mechanical circulatory support.

Background: Cerebral protection during aortic arch surgery can be performed using various surgical strategies. We retrospectively analyzed our results of different brain protection modalities during aortic arch surgery., Methods: Between January 2003 and November 2009, 636 consecutive patients underwent aortic arch replacement surgery using unilateral antegrade cerebral perfusion (UACP [n=123]), bilateral antegrade cerebral perfusion (BACP [n=242]), retrograde cerebral perfusion (RCP [n=51]), or deep hypothermia and circulatory arrest (DHCA [n=220]). Mean age of patients was 62±14 years, 64% were male, 15% were reoperations, and 37% were performed for acute type A dissections. Mean follow-up was 4.9±0.1 years and was 97% complete., Results: Circulatory arrest time was 22±17 minutes UACP, 23±21 minutes BACP, 18±12 minutes RCP, and 15±13 minutes DHCA; p<0.001). Early mortality was 11% (n=72) and was not different between the surgical groups. Stroke rate was 9% for ACP patients (n=33) versus 15% (n=39) for patients who did not receive ACP (p=0.035). Independent predictors of stroke were type A aortic dissection (odds ratio [OR], 1.9; 95% confidence interval [CI], 1.3 to 3.2; p<0.001), age (OR, 1.04; 95% CI, 1.01 to 1.06; p=0.001), duration of circulatory arrest (OR, 1.01, 95% CI, 1.002 to 1.03; p=0.02), and total aortic arch replacement (OR, 2.7; 95% CI, 1.3 to 5.7; p=0.005). Five year survival was 68%±4% and was not significantly different between groups., Conclusions: Antegrade cerebral perfusion is associated with significantly less neurologic complications than RCP and DHCA, despite longer circulatory arrest times. Medium-term survival is worse for patients with postoperative permanent neurologic deficit and preoperative type A aortic dissection., (Copyright © 2012 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.)

Objective: Iatrogenic aortic dissection (IAD) is a rare complication of cardiac procedures. We herein describe our management and results of this complication., Methods: A total of 55 279 patients underwent open heart surgery at our centre from 1995 to 2010, and 135 262 patients underwent cardiac catheterization over the same time period. We identified 48 patients from this cohort who underwent emergency surgery for IAD that occurred either during or shortly after cardiac surgery, or following cardiac catheterization., Results: The incidence of IAD was 0.06% (n = 36) for cardiac surgical procedures and 0.01% (n = 12) for cardiac catheterization procedures. The mean patient age was 66 ± 14 years and 50% were female. Intraoperative IAD occurred during aortic cannulation in 12 patients, insertion of the cardioplegia cannula in 7 patients, manipulation of the aortic crossclamp in 4 patients or during other events in 8 patients. IAD occurred early postcardiac surgery in 5 patients, and during cardiac catheterization in the remaining 12 patients. IAD was treated by emergent replacement of the ascending aorta and the aortic arch (when involved), as well as aortic root replacement or repair as indicated. Early mortality was 41.7: 35.5% for intraoperative IAD, 60.0% for postoperative IAD and 50.0% for cardiac catheterization-associated IAD (P = 0.5). Histological investigation revealed atherosclerosis in 61.2% of patients, cystic medial necrosis in 22.2%, aortitis in 2.8% and other pathologies in 13.8%. Follow-up was 100% complete with a 5-year survival of 40 ± 0.4%., Conclusion: IAD is a rare but dangerous complication of cardiac surgery and cardiac catheterization, and is frequently associated with pre-existing aortic pathology.

Objectives: The objective of this study was to identify and examine ICD utilization in a large group of eligible coronary artery bypass grafting (CABG) patients with impaired left ventricular function., Methods: We conducted a retrospective study of ICD eligible patients who had previously undergone CABG surgery between March 1, 1995 and June 30, 2008 at a single tertiary care institution. All patients with a pre-operative left ventricular ejection fraction (LVEF) ≤ 35% were considered ICD eligible. The events of interest were ICD implantation and mortality, based on administrative data linkage., Results: A total of 1,169 out of 11,931 CABG patients operated on during the same period had LVEF ≤ 35% and were defined as ICD eligible (mean EF = 27.3% +/- 6.4%). Of these eligible patients, only 101 received an ICD during follow-up (8.6%). The median time to implant was 255 days (14-1078). The single variable that independently predicted eventual ICD implantation was a history of arrhythmia (OR = 7.4; CI, 4.4-12.2). The variables that predicted not having an ICD implanted during follow-up included the need for urgent CABG (OR = 0.5; CI, 0.2-0.9), age > 70 years (OR = 0.5; CI, 0.3-0.8), female gender (OR = 0.2; CI,0.1-0.6), or having chronic obstructive lung disease (OR = 0.5; CI,0.3-0.8). As a data validation step, a series of consecutive patient records were reviewed (n=80) showing that fewer than 23% underwent appropriate follow-up EF assessment post revascularization., Conclusion: Our findings suggest that CABG patients with ischemic cardiomyopathy have low rates of ICD utilization. This is particularly evident among females and elderly patients. Furthermore our data suggests that few patients post-revascularization undergo follow-up EF assessment despite current guidelines likely contributing to the low rates of ICD utilization.

Aims: Characterize mononuclear cell migration after acute-myocardial infarction (MI)., Material and Methods: Male Lewis rats underwent a left thoracotomy and ligation of the left anterior descending coronary artery (MI group). Control animals underwent thoracotomy without ligation (Sham group). Animals were sacrificed at 0, 2, 4, or 24 hr after the onset of ischemia. Leukocyte migration was assessed using isolated and In(111) labeled mononuclear cells (injected at the onset of ischemia) and gamma-count determined at 24 hours. Inhibition of migration was evaluated with monoclonal anti alpha4 and/or beta2 antibodies., Results: Serum troponin was significantly elevated in animals with MI as compared with Sham (p = .017). Labeled mononuclear cell migration was five-fold higher in MI-treated animals than in Sham (p = .006). ED-1 positive mononuclear cells were confirmed in the left myocardium after 24 hr of ischemia. MCP-1 mRNA was significantly elevated in the left myocardium at 2 hr and 4 hr and peaked at 24 hr (p <.05). In addition, alpha4 integrin blockade inhibited labeled mononuclear cell migration by 22%. Blockade of beta2 integrin inhibited mononuclear cell migration by 48%, while the combined alpha4+beta2 blockade resulted in 59% inhibition of labeled mononuclear cell migration compared with treatment with isotype control antibody (p = .001)., Conclusions: Significant ED1+ mononuclear cell migration within 24 hr of MI correlated with peak MCP-1 mRNA. Monoclonal antibody blockade suggested that early mononuclear cell migration is dependent only in part on alpha4 and beta2 integrins.

Background: From March to July 2009, influenza A (H1N1) 2009 (H1N1-2009) virus emerged as a major cause of respiratory failure that required mechanical ventilation. A small proportion of patients who had this condition developed severe respiratory failure that was unresponsive to conventional therapeutic interventions. In this report, we describe characteristics, treatment, and outcomes of critically ill patients in Canada who had H1N1-2009 infection and were treated with extracorporeal lung support (ECLS)., Methods: We report the findings of a case series of six patients supported with ECLS who were included in a cohort study of critically ill patients with confirmed H1N1-2009 infection. The patients were treated in Canadian adult and pediatric intensive care units (ICUs) from April 16, 2009 to August 12, 2009. We describe the nested sample treated with ECLS and compare it with the larger sample., Results: During the study period, 168 patients in Canada were admitted to ICUs for severe respiratory failure due to confirmed H1N1-2009 infection. Due to profound hypoxemia unresponsive to conventional therapeutic interventions, six (3.6%) of these patients were treated with ECLS in four ICUs. Four patients were treated with veno-venous pump-driven extracorporeal membrane oxygenation (vv-ECMO), and two patients were treated with pumpless lung assist (NovaLung iLA). The mean duration of support was 15 days. Four of the six patients survived (66.6%), one of the surviving patients was supported with iLA and the other three surviving patients were supported with ECMO. The two deaths were due to multiorgan failure, which occurred while the patients were on ECLS., Interpretation: Extracorporeal lung support may be an effective treatment for patients who have H1N1-2009 infection and refractory hypoxemia. Survival of these patients treated with ECLS is similar to that reported for patients who have acute respiratory distress syndrome of other etiologies and are treated with ECMO.

Background: Wait times for cardiac surgery are well established but may not reflect the total wait time patients experience., Methods: The Maritime Heart Center (Halifax, Nova Scotia) cardiac surgery database was used to identify all consecutive patients who underwent elective coronary artery bypass graft surgery between 2002 and 2005 from a single urgency queue. The provincial physician billing database provided a timeline record of dates, physician visits, and diagnoses or procedures performed for each patient. This information was used to assess total and component wait times leading to cardiac surgery., Results: A total of 705 consecutive patients were included and stratified based on geographical location: urban Halifax Regional Municipality (HRM; n=222), urban non-HRM (n=220) and rural (n=263). Patients from all regions did not differ in age, sex, comorbidities or ventricular function. Using a traditional definition of wait time (time listed), patients waited a median of 56 days (interquartile range [IQR] 38 to 77 days). In comparison, the total wait times based on the time from presentation to surgery were a median of 109 days (IQR 56 to 184 days) for HRM, a median of 121 days (IQR 77 to 184 days) for urban non-HRM and a median of 123 days (IQR 79 to 169 days) for rural patients (P-value nonsignificant). Two modes of presentation emerged that were not influenced by a patient's geographical location. Patients who presented to the emergency department (n=229) waited a median of 73 days. This was significantly less than patients who presented to their family physician (n=476), who waited a median of 135 days (P<0.001). The difference in overall wait for patients presenting to the emergency room was a result of a shorter wait time for referral to a specialist and from seeing a specialist to catheterization., Conclusion: The present pilot study demonstrated that total patient wait times for cardiac care and surgery in Nova Scotia are significantly longer (more than twofold) than traditionally reported wait times for surgery alone.

Background: Heat shock (HS) treatment has been suggested to confer myocardial protection following ischemia. However, the effects of HS on left ventricular (LV) remodeling weeks after infarction have yet to be described., Methods: Myocardial infarction (MI) was created by coronary ligation in Lewis rats. Two experimental groups of animals were created: HS+MI group (n = 13) and MI group (n = 13). HS treatment consisted of an elevation in core temperature to 42 degrees C for 15 min, 24 hr prior to MI. LV remodeling was assessed by transthoracic echocardiography (day 0, 1, 7, and 28) and by morphometric histology (day 28)., Results: There was no significant difference in infarct size (TTC stain 24 hr) between HS+MI and MI groups. Using transthoracic echo there was a significant preservation of LV ejection fraction and fractional shortening in the HS+MI group as compared to MI group (7 and 28 days). Similar trends were seen by histology at 28 days but failed to reach significance. HSP27 expression by myocardial cells was shown to remain up-regulated (at 28 days) in both groups at the edges of the infarct area as compared to control myocardium., Conclusions: Our findings suggest that HS treatment prior to MI can result in a significant decrease in LV remodeling independent of a reduction in infarct size.

Background and Aim: Great mediastinal veins may be reconstructed using autologous, synthetic, or allograft conduits. Autologous conduits have been found superior to other conduit options. The superficial femoral vein (SFV) offers excellent early patency, minimal lower limb morbidity, and ease of harvest without accessory suture lines. Although rarely used, the SFV provides an acceptable alternative for conduit in large vein reconstructions., Methods: Two recent cases using SFV for great mediastinal vein reconstruction were reviewed and operative technique of vein harvest detailed., Results: This is the first report of successful reconstruction of a left superior vena cava using SFV conduit. Both superior vena cava (SVC) reconstructions reported were perfectly patent at intermediate term follow-up (20 and 14 months) as determined by computed tomography angiogram or magnetic resonance imaging., Conclusions: Successful and durable reconstruction of the SVC or a persistent left subclavian vein is possible with minimal morbidity using the SFV.

Transit-time flowmetry enables immediate intraoperative assessment of blood flow parameters in coronary artery bypass grafts (CABG). The present study assesses the predictive value of measured graft flows on early and medium-term outcomes. All cardiac surgery patients with measured graft flows were included. The last intraoperative flow measurements recorded using the Medtronic Butterfly Flowmetry system were used for analysis. Patients were separated into two groups: patients with normal flow in all grafts or patients with abnormal flow > or =1 graft. Any pulsatility index (pulsatility index=min-max flow/mean flow) < or =5 was determined to be normal flow. The study population included 985 patients. Nineteen percent of patients had abnormal flow in > or =1 graft. Overall in-hospital mortality was 4.7% and not significant between the two groups. After adjusting for covariates, the in-hospital composite outcome for adverse cardiac events was more prevalent in the abnormal flow group (31% vs. 17%; P<0.0001) with an odds ratio of 1.7 (CI 1.1-2.7). Survivors to discharge had a mean follow-up of 1.8 years. However, abnormal flow was not an independent predictor of the medium-term mortality and readmission to hospital for cardiac reason following discharge. Our findings suggest that abnormal flows measured intraoperatively are independently associated with short-term in-hospital adverse outcome.

The present case report describes the spontaneous formation of blood clots in the right and left sides of the circulation, despite good anticoagulation, in a patient undergoing coronary bypass surgery. The authors hypothesize that, because the patient turned out to have positive serology for heparin-induced thrombocytopenia that was not diagnosed preoperatively, heparin-induced thrombocytopenia thrombosis may account for all findings. The clinical scenario is described in detail and potential explanations and relevance are discussed.

Objectives: The increasing cost of intensive care unit (ICU) care and limited resources lead us to evaluate predictors of ICU readmission in a large group of patients undergoing coronary artery bypass surgery (CABG) at one institution., Methods: Two thousand one hundred and seventeen consecutive patients undergoing CABG surgery between January 1999 and August 2001 were reviewed retrospectively. The reasons for readmission were determined by reviewing the physician's progress notes, the nurse's progress notes and the discharge summary., Results: A total of 75 patients were readmitted to ICU during the study period for a readmission rate of 3.6%. Eight of these were readmitted a second time, and three a third time, for a total of 86 readmissions. Forty-seven patients died, for a mortality of 2% among patients that were not readmitted to the ICU, compared to 17% among those who were readmitted (P<0.0001). Median hospital length of stay was 6 days for patients not readmitted and 23 days for those readmitted (P<0.0001). The most common reason for readmission was respiratory failure, accounting for 47% of readmissions (n=40). Multivariate analysis using a stepwise logistic regression analysis revealed that preoperative renal failure (odds ratio 2.13; CI 1.03-4.41) and prolonged mechanical ventilation of >24 h (odds ratio 10.52; CI 6.18-17.91) were the only independent predictors for readmission to the ICU after CABG., Conclusions: Identification of patients that have preoperative renal failure or that required initial ventilation for more than 24 h after CABG may help to identify patients at risk of ICU readmission. Preemptive strategies designed to optimize these high-risk patients may improve outcomes.

Objective: To study patterns of failure following primary antireflux surgery and to evaluate efficacy of reoperation using a left thoracoabdominal Collis gastroplasty and selective fundoplication., Methods: Thirty-one patients who underwent reoperative antireflux surgery between 1991 and 2000 were studied. Transabdominal fundoplication had been performed in 21 patients, and ten patients had a partial fundoplication by left thoracotomy, 1-33 years (mean, 15 years) previously. All patients presented with clinically disabling symptoms. Objective studies documented for all patients, a disrupted fundoplication, a short esophagus, and an associated hiatus hernia (Type I: 21 patients, 68%; Type III: ten patients, 32%), esophagitis (nine patients, 29%), and Barrett's mucosa (five patients, 16%). Abnormal esophageal motility was found in nine of 26 (36%) patients studied. All patients were reoperated using a left thoracoabdominal approach, with epidural analgesia. A Collis gastroplasty was used to lengthen the esophagus, incorporating a complete (24 patients, 77%) or partial (seven patients, 23%) fundoplication based of preoperative esophageal function studies., Results: There was no perioperative mortality. Median length of hospitalization was 8 days, and was uncomplicated for 18 (58%) patients. Postoperative morbidity was considered minimal, and comprised left lower lobe infiltrates (six patients, 19%), atrial fibrillation (three patients, 10%), urinary tract infection (one patient, 3%), superficial wound infection (one patient, 3%), aspiration (one patient, 3%), and nausea (one patient, 3%). Median follow-up was 42 months (6-105 months), and was complete for 29 patients. Six patients (21%) had moderate-severe post-thoracotomy pain, for up to 18 months postoperatively, and five patients (17%) required esophageal dilation, ranging from two to six dilations within the first 6 months after surgery. Overall, 93% (27/29) of patients were satisfied with the results of surgery, in terms of quality of swallowing and control of preoperative symptoms., Conclusions: In this series, failure of primary antireflux surgery was related to short esophagus. Intermediate-term subjective results of reoperative antireflux surgery were good for selected patients who undergo esophageal lengthening and fundoplication. The left thoracoabdominal approach was safe, generally well tolerated, and provided excellent exposure of the esophagogastric junction for complex reoperative antireflux surgery.