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Imaging the heart is one of the most technically challenging applications of Computed Tomography (CT) due to the presence of cardiac motion limiting optimal visualization of small structures such as the coronary arteries. Electrocardiographic gating during CT data acquisition facilitates motion free imaging of the coronary arteries. Since publishing the first version of the Canadian Association of Radiologists (CAR) cardiac CT guidelines, many technological advances in CT hardware and software have emerged necessitating an update. The goal of these cardiac CT practice guidelines is to present an overview of the current evidence supporting the use of cardiac CT in various clinical scenarios and to outline standards of practice for patient safety and quality of care when establishing a cardiac CT program in Canada. [ABSTRACT FROM AUTHOR]

Gated radionuclide angiography and myocardial perfusion imaging were developed in the United States and Europe in the 1970's and soon adopted in Canadian centers. Much of the early development of nuclear cardiology in Canada was in Toronto, Ontario and was quickly followed by new programs across the country. Clinical research in Canada contributed to the further development of nuclear cardiology and cardiac PET. The Canadian Nuclear Cardiology Society (CNCS) was formed in 1995 and became the Canadian Society of Cardiovascular Nuclear and CT Imaging (CNCT) in 2014. The CNCS had a major role in education and advocacy for cardiovascular nuclear medicine testing. The CNCS established the Dr Robert Burns Lecture and CNCT named the Canadian Society of Cardiovascular Nuclear and CT Imaging Annual Achievement Award for Dr Michael Freeman in memoriam of these two outstanding Canadian leaders in nuclear cardiology. The future of nuclear cardiology in Canada is exciting with the expanding use of SPECT imaging to include Tc-99m-pyrophosphate for diagnosis of transthyretin cardiac amyloidosis and the ongoing introduction of cardiac PET imaging. [ABSTRACT FROM AUTHOR]

This article presents the nursing experience in caring for a male Canadian tourist who suffered from lower extremity arterial occlusive disease, as known as leg stroke. The nursing care period was from 2018.01.25 to 2018.02.01. with the application of the Roy's Adaptation Model. Comprehensive information was obtained via observation, physical evaluation, direct nursing, interview, and medical record review. The main health issues identified were acute pain, altered peripheral tissue perfusion, and anxiety. The patient was encouraged to perform muscle relaxation techniques such as massage, to ease pain and improve tissue perfusion. To reduce the patient's anxiety level, solutions were done to overcome cultural and language barriers between the patient and his caregivers. With the increasing number of foreign patients, medical professionals deal with different languages and cultures. It is recommended that nurses should embrace cultural differences, provide individual care, customize multilingual educational handouts, and assist patients to download an application for health self-monitoring. This nursing experience serves as a reference for nurses who encounter foreign patients in the future. [ABSTRACT FROM AUTHOR]

New cardiopulmonary bypass device techniques emerge and are reported in the scientific literature. The extent to which they are actually adopted into clinical practice is not well known. Since 1989, we have periodically surveyed pediatric cardiac centers to ascertain practice patterns. In December 2016, a 186-question perfusion survey was distributed to pediatric cardiac surgery centers all over the world using a Webbased survey tool. Responses were received from 93 North American (NA) centers (the United States and Canada) and 67 non-NA (NNA) centers, representing 19,645 cumulative annual procedures in NA and 27,776 in NNA centers on patients <18 years. Wide variation in practice was evident across geographic regions. However, the most common pediatric circuit consisted of a hard-shell (open) venous reservoir, an arterial roller pump, and a hollow-fiber membrane oxygenator with a separate or integrated arterial filter. Compared with our previous surveys, there was increased utilization of all types of safety devices. The use of an electronic perfusion record was reported by 50% of NA centers and 31% of NNA centers. There was wide regional variation in cardioplegia delivery systems and cardioplegia solutions. Seventy-nine percent of the centers reported the use of some form of modified ultrafiltration. The survey demonstrated that there remains variation in perfusion practice for pediatric patients. Future surveys will be useful to evaluate the adoption of emerging perfusion practice guidelines. [ABSTRACT FROM AUTHOR]

Timely diagnosis of brain death (BD) is critical as it prevents unethical and futile continuation of support of vital organ functions when the patient has passed. Furthermore, it helps with avoiding the unnecessary use of resources and provides early opportunity for precious organ donation. The diagnosis of BD is mainly based on careful neurological assessment of patients with an established underlying diagnosis of neurological catastrophe capable of causing BD.Ancillary testing, however, is tremendously helpful in situations when the presence of confounders prevents or delays comprehensive neurological assessment. Traditionally, four-vessel digital subtraction angiography and computed tomography angiography have been used for blood flow (BF) examinations of the brain. The lack of BF in the intracranial arteries constitutes conclusive evidence that the brain is dead. However, there is an apparent discrepancy between the BF and sufficient cerebral perfusion; several studies have shown that in 15% of patients with confirmed clinical diagnosis of BD, BF is still preserved. In these patients, cerebral perfusion is significantly impaired. Hence, measurement of cerebral perfusion rather than BF will provide a more precise assessment of the brain function.In this review article, we discuss a brief history of BD, our understanding of its complex pathophysiology, current Canadian guidelines for the clinical diagnosis of BD, and the ancillary tests-specifically CT perfusion of the brain that help us with the prompt and timely diagnosis of BD.

Background: The underlying mechanisms responsible for the clinical benefits following coronary sinus narrowing and pressure elevation remain unclear. The present study aims to investigate whether coronary sinus narrowing improves the indexes of coronary microcirculatory function., Methods: Patients with refractory angina who had a clinical indication for reducer implantation underwent invasive physiological assessments before and 4 months after the procedure. The primary outcome was the change in the values of the index of microcirculatory resistance. Secondary end points included changes in coronary flow reserve and the resistive resistance ratio values. Angina status was assessed with the Canadian Cardiology Society class and the Seattle Angina Questionnaire., Results: Twenty-four patients with a history of obstructive coronary artery disease and prior coronary revascularization (surgical and percutaneous) treated with reducer implantation were enrolled, and 21 of them (87%) underwent repeated invasive coronary physiological assessment after 4 months. The index of microcirculatory resistance values decreased from 33.35±19.88 at baseline to 15.42±11.36 at 4-month follow-up ( P <0.001; mean difference, -17.90 [95% CI, -26.16 to -9.64]). A significant (≥20% from baseline) reduction of the index of microcirculatory resistance was observed in 15 (71.4% [95% CI, 47.8%-88.7%]) patients. The number of patients with abnormal index of microcirculatory resistance (≥25) decreased from 12 (57%) to 4 (19%; P =0.016). Coronary flow reserve increased from 2.46±1.52 to 4.20±2.52 (mean difference, 1.73 [95% CI, 0.51-2.96]). Similar findings were observed for resistive resistance ratio values. Overall, 16 patients (76.1%) had an improvement of 1 Canadian Cardiology Society class. Seattle Angina Questionnaire summary score increase of around 3 points (3.01 [95% CI, 1.39-4.61])., Conclusions: Coronary sinus reduction implantation is associated with a significant improvement in the parameters of coronary microcirculatory function. These findings provide insights into the improvement of angina symptoms and may have implications for the treatment of coronary microvascular dysfunction., Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT05174572., Competing Interests: Disclosures Dr Campo received research grants from SMT, Eukon, Siemens, GE Healthcare, and Abbott Vascular outside the present work. Dr Biscaglia received research grants from SMT, Eukon, Siemens, GE Healthcare, and Abbott Vascular outside the present work. Dr Banai is the medical director of Neovasc, Inc. The other authors report no conflicts.

Hypoplastic left heart syndrome (HLHS) is a rare and severe congenital cardiac defect. Approximately 1000 infants are born with HLHS in the United States every year. Healthcare collaboratives over the last decade have focused on sharing patient experiences and techniques in an effort to improve outcomes. In 2010, cardiologists and patient families joined together to improve the care of HLHS patients by forming the National Pediatric Cardiology Quality Improvement Collaborative (NPC-QIC). Sixty-six of the approximately 110 institutions caring for patients with HLHS in the United States and Canada are now members of NPC-QIC. In 2017, cardiovascular perfusionists joined the collaborative as another specialty involved in the care of HLHS patients. Perfusionists and cardiac surgeons developed the collaborative’s first conduct of perfusion survey for the Norwood Stage 1 procedure, specifically targeting the provision of cardiopulmonary bypass for patients with HLHS. This manuscript discusses the results of this survey, unveiling a significant variance in the conduct of perfusion for this patient population. [ABSTRACT FROM AUTHOR]

Background: We aimed to determine the frequency and predictors of exercise limitation after pulmonary embolism (PE) and to assess its association with health-related quality of life (HRQoL) and dyspnea.Methods: One hundred patients with acute PE were recruited at five Canadian hospitals from 2010 to 2013. Cardiopulmonary exercise testing (CPET) was performed at 1 and 12 months. Quality of life (QoL), dyspnea, 6-min walk distance (6MWD), residual clot burden (perfusion scan, CT pulmonary angiography), cardiac function (echocardiography), and pulmonary function tests (PFTs) were measured during follow-up. The prespecified primary outcome was percent predicted peak oxygen uptake (Vo2 peak) < 80% at 1-year CPET.Results: At 1 year, 40 of 86 patients (46.5%) had percent predicted Vo2 peak < 80% on CPET, which was associated with significantly worse generic health-related QoL (HRQoL), PE-specific HRQoL and dyspnea scores, and significantly reduced 6MWD at 1 year. Predictors of the primary outcome included male sex (relative risk [RR], 3.2; 95% CI, 1.3-8.1), age (RR, 0.98; 95% CI, 0.96-0.99 per 1-year age increase), BMI (RR 1.1; 95% CI, 1.01-1.2 per 1 kg/m2 BMI increase), and smoking history (RR, 1.8; 95% CI, 1.1-2.9), as well as percent predicted Vo2 peak < 80% on CPET at 1 month (RR, 3.8; 95% CI,1.9-7.2), and 6MWD at 1 month (RR, 0.82; 95% CI, 0.7-0.9 per 30-m increased walking distance). Baseline or residual clot burden was not associated with the primary outcome. Mean PFT and echocardiographic results (pulmonary artery pressure, right and left ventricular systolic function) at 1 year were similarly within normal limits in both patients with exercise limitations and those without such limitations.Conclusions: Almost half of patients with PE have exercise limitation at 1 year that adversely influences HRQoL, dyspnea, and walking distance. CPET or 6MWD testing at 1 month may help to identify patients with a higher risk of exercise limitation at 1 year after PE. Based on our results, we believe that the deconditioning that occurs after acute PE could underlie this exercise limitation, but we cannot exclude the fact that this may have been present before PE.Trial Registry: ClinicalTrials.gov; No.: NCT01174628; URL: www.clinicaltrials.gov. [ABSTRACT FROM AUTHOR]

Introduction: Years of experience and level of education are two important determinants of a clinician's expertise. While entry-to-practice criteria for admission to perfusion training in Canada changed from clinical experience-based criteria to education-based criteria in 2006, the effects of these changes have not been studied. Objective: To determine the academic and clinical backgrounds of perfusionists in Canada, ascertain perceptions about the adequacy of training and evaluate the effects of the changes on the composition of the perfusion community of Canada. Methods: An electronic questionnaire was distributed to all practicing perfusionists in Canada, addressing details regarding clinical experience, academic education and perceptions about the adequacy of training. Results: Two hundred and twenty-eight questionnaires were completed, representing a 72% response rate. Perfusionists admitted under academic-based criteria have significantly higher levels of education (100% degree holders vs 69.1%, p<0.001), but less antecedent clinical training and experience (median, IQR: 0, 0 - 4.5 years vs 2, 2 - 8 years, p<0.0001), are younger (median age range 31-35 years vs 51-55 years, p<0.0001), more likely to be female (58.7% vs 41.3%, p=0.006) and are significantly more likely to enter perfusion because of attraction to the type of work (p=0.045). Many perfusionists (70, 32%) in Canada believe themselves inadequately trained for their clinical assignments outside the OR. In addition, 19% of perfusionists plan to retire over the next 10 years. Conclusions: The introduction of education-based entry criteria has changed the academic and clinical experience levels of perfusionists in Canada. Strategies designed to better prepare perfusionists for their clinical assignments outside the OR are merited. [ABSTRACT FROM AUTHOR]

Radionuclide perfusion studies have an established ancillary role in determination of death by neurologic criteria (DNC). While critically important, these examinations are not well understood by individuals outside of the imaging specialties. The purpose of this review is to clarify relevant concepts and nomenclature and provide a lexicon of relevant terminology of value to non-nuclear medicine practitioners who wish to better understand these examinations. Radionuclides were first employed to evaluate cerebral blood flow in 1969. Radionuclide DNC examinations that use lipophobic radiopharmaceuticals (RPs) entail a flow phase followed immediately by blood pool images. On flow imaging, presence of intracranial activity within the arterial vasculature is scrutinized following arrival of the RP bolus into the neck. Lipophilic RPs designed for functional brain imaging were introduced to nuclear medicine in the 1980s and were engineered to cross the blood-brain-barrier and be retained in the parenchyma. The lipophilic RP 99m Tc-hexamethylpropyleneamine oxime ( 99m Tc-HMPAO) was first used as an ancillary investigation in DNC in 1986. Examinations using lipophilic RPs entail both flow and parenchymal phase images. According to some guidelines, parenchymal phase uptake should be assessed by tomographic imaging, while other investigators consider simple planar imaging sufficient. Findings of perfusion on either the flow or parenchymal phase of the examination effectively precludes DNC. If the flow phase is omitted or somehow compromised, the parenchymal phase remains sufficient for DNC. A priori, parenchymal phase imaging is superior to flow phase imaging for several reasons and lipophilic RPs are favoured over lipophobic RPs in that both flow and parenchymal phase imaging are performed. Disadvantages of lipophilic RPs are increased cost and the need to procure them from a central laboratory, which can prove difficult, especially outside usual working hours. According to most current guidelines, both lipophilic and lipophobic RP categories are acceptable for use in ancillary investigations in DNC, with a growing overt preference for studies using the lipophilic RPs based on their ability to capture the parenchymal phase. The new adult and pediatric Canadian recommendations favour use of lipophilic RPs to variable degrees, specifically 99m Tc-HMPAO, the lipophilic moiety which has undergone the greatest validation. Although ancillary use of radiopharmaceuticals is quite settled in multiple DNC guidelines and best practices, several areas of further research remain open to investigation. Examens auxiliaires de perfusion nucléaire pour la détermination du décès selon des critères neurologiques : méthodes, interprétation et lexique-un guide de l'utilisateur à l'intention du clinicien., (© 2023. The Author(s).)

Objectives: Bowel resection is an important component of surgical management of women with advanced gynecologic malignancies. Real-time intraoperative assessment of anastomotic perfusion with indocyanine green fluorescence angiography (ICG-FA) is a recent technique that has been shown to effectively evaluate perfusion of large and small bowel anastomoses. The objective of this study was to capture national practice patterns, characterize facilitators and barriers to ICG-FA utilization for bowel perfusion assessment, and identify opportunities for further education across Canada. Methods: A needs assessment survey was developed with a focus group of key stakeholders in the field, as well as a methodologist, and piloted in advance to distribution. The survey captured basic sociodemographics, work history, facilitators and barriers to use of ICG-FA for bowel perfusion assessment, and modalities for further education (e.g., peer-reviewed article, surgical video, national/ international conference, local grand rounds, and invited experts for practical training). On July 1, 2021, the survey was distributed to 115 gynecologic oncologists registered through the Society of Gynecologic Oncology of Canada. Responses were collected until September 1, 2021. Results: The response rate was 31% (n =37), with respondents from all Canadian provinces. Approximately three-quarters (78%) of respondents identified as women, and the majority (60%) have been practicing gynecologic oncology for less than ten years. Of the respondents, 81% (n =30) performed bowel resection, and 67% (n =20) used ICG-FA for anastomotic perfusion assessment after bowel surgery. The three most reported barriers to integrating ICG-FA into routine clinical practice were the lack of training (30%), knowledge (27%), and equipment (27%). Surgical videos were the highest-ranked educational modality, followed by national/international conferences and peer- reviewed articles. Conclusions: ICG-FA for bowel perfusion assessment is a valuable tool that can be used with other risk-assessment strategies to guide operative decision-making in gynecologic oncology. However, further training across multiple educational modalities is needed to build knowledge among the Canadian gynecologic oncologic community, with surgical videos serving as the preferred educational modality. Additionally, more funding for necessary equipment will facilitate the uptake of this tool. This represents a national practice improvement opportunity. [ABSTRACT FROM AUTHOR]

Introduction: The process of controlled organ donation after circulatory determination of death (cDCDD) results in ischaemic injury to organs and leads to poorer outcomes in organ recipients. Although not yet used in Canada, normothermic regional perfusion (NRP) is a perfusion technology used postmortem with cDCDD donors to selectively restore perfusion of oxygenated blood to target organs in situ, reversing ischaemic injury and improving organ viability and post-transplant outcomes. However, NRP poses significant ethical challenges. To preserve trust in deceased donation, these ethical challenges must be addressed to the satisfaction of Canadian stakeholders before NRP's implementation. This study will identify ethical issues pertaining to NRP and explore perspectives of NRP among key stakeholders. By developing an explanatory framework delineating how stakeholder perceptions of NRP's ethical implications impact trust in Canada's donation and transplantation systems, this study will inform the development of responsible policy on NRP's use in Canada., Methods and Analysis: This study includes two workstreams. Workstream 1 is a scoping review of medical and bioethical literature to identify ethical issues stemming from NRP. We will apply a common search string across Medline, PubMed (other than Medline) and Embase to identify relevant articles. We will identify grey literature through Google searches, websites of organ donation organisations and consultation with our research network. No date limits will be applied. All peer-reviewed publications, commentaries, editorials or documents that engage with ethical issues in NRP (or conceptual and empirical issues as they relate to these ethical issues) will be included. News articles, conference abstracts and publications not in English will be excluded. Workstream 2 consists of interviews with healthcare providers, institutional stakeholders, organ recipients and deceased donors' family members (n=24-36), as well as focus groups with healthcare providers involved in deceased donation and transplantation (n = 20-32). Constructivist grounded theory methodology will guide data collection and analysis in workstream 2., Ethics and Dissemination: This study was approved by Western University's research ethics committee (Western REM; ID: 120001). All participants will be asked to provide written informed consent to participate. Findings will be shared with Canadian organ donation and transplantation organisations, presented at national conferences and published in medical journals., Competing Interests: Competing interests: CW receives consulting income from Cardialen, Eli Lilly & Company and Research Triangle Institute International. MS receives a stipend for his work as the Regional Medical Lead (Donation) with Ontario Health—Trillium Gift of Life Network, and holds CIHR and NFRF grants for projects related to organ donation. All other authors have no competing interests to declare., (© Author(s) (or their employer(s)) 2022. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Study design:Prospective observational study of acute spinal cord-injured (SCI) patients.Objectives:To determine how effectively mean arterial blood pressure (MAP) and spinal cord perfusion pressure (SCPP) are maintained at target levels in acute SCI patients.Setting:Single-institution study at a Canadian level-one trauma center.Methods:Twenty-one individuals with cervical or thoracic SCI were enrolled within 48 h of injury. A lumbar intrathecal drain was inserted for monitoring intrathecal cerebrospinal fluid pressure (ITP). The MAP was monitored concurrently with ITP, and the SCPP was calculated. Data was recorded hourly from the time of first assessment until at least the end of the 5th day post injury.Results:All subjects had at least one recorded episode with a MAP below 80 mm Hg, and 81% had at least one episode with a MAP below 70 mm Hg. On average, subjects with cervical injuries had 18.4% of their pressure recordings below 80 mm Hg. Subjects with thoracic cord injuries had on average 35.9% of their MAP recordings <80 mm Hg.Conclusion:It is common practice to establish MAP targets for optimizing cord perfusion in acute SCI. This study suggests that even in an acute SCI referral center, when prospectively scrutinized, the actual MAP may frequently fall below the intended targets. Such results raise awareness of the vigilance that must be kept in the hemodynamic management of these patients, and the potential discrepancy between routinely setting target MAP according to 'practice guidelines' and actually achieving them. [ABSTRACT FROM AUTHOR]

The article focuses on the queries on the legal and ethical consent of donation after cardiac death (DCD), particularly the role of substitute decision-makers (SDMs) in Canada. It explores the history of DCD, brain death standard and the general development of the Pittsburgh Protocol which examined the issues on legal and ethical donor consent to procedures ancillary to donation process. Moreover, the legal ability of physicians on donor consent has been questioned by several commentators.

Despite the promise of proangiogenic gene therapy most clinical trials have failed to show benefit for the primary end point analysis. The NOGA angiogenesis Revascularization Therapy: assessment by RadioNuclide imaging (NORTHERN) trial was a double-blind, placebo-controlled study of intramyocardial vascular endothelial growth factor (VEGF165) gene therapy versus placebo, involving seven sites across Canada, designed to overcome major limitations of previous proangiogenic gene therapy trials. A total of 93 patients with refractory Canadian Cardiovascular Society (CCS) class 3 or 4 anginal symptoms were randomized to receive 2,000 µg of VEGF plasmid DNA or placebo (buffered saline) delivered via the endocardial route using an electroanatomical NOGA guidance catheter. There was no difference between the VEGF-treated and the placebo groups in the primary end point of change in myocardial perfusion from baseline to 3 or 6 months, assessed by single photon emission tomography (SPECT) imaging, although a significant reduction in the ischemic area was seen in both groups. Also, similar improvements in exercise treadmill time and anginal symptoms were seen in the VEGF and the placebo groups at 3 and 6 months, although again there were no differences between these groups. Despite the intramyocardial administration of a high “dose” of plasmid DNA using a percutaneous guidance catheter system, there was no benefit of VEGF gene therapy at 3 or 6 months for any of the end points studied.Molecular Therapy (2009) 17 6, 1109–1115 doi:10.1038/mt.2009.70 [ABSTRACT FROM AUTHOR]

Introduction: Severe traumatic brain injury (TBI) is a catastrophic neurological condition with significant economic burden. Early in-hospital mortality (<48 hours) with severe TBI is estimated at 50%. Several clinical examinations exist to determine brain death; however, most are difficult to elicit in the acute setting in patients with severe TBI. Having a definitive assessment tool would help predict early in-hospital mortality in this population. CT perfusion (CTP) has shown promise diagnosing early in-hospital mortality in patients with severe TBI and other populations. The purpose of this study is to validate admission CTP features of brain death relative to the clinical examination outcome for characterizing early in-hospital mortality in patients with severe TBI., Methods and Analysis: The Early Diagnosis of Mortality using Admission CT Perfusion in Severe Traumatic Brain Injury Patients study, is a prospective cohort study in patients with severe TBI funded by a grant from the Canadian Institute of Health Research. Adults aged 18 or older, with evidence of a severe TBI (Glasgow Coma Scale score ≤8 before initial resuscitation) and, on mechanical ventilation at the time of imaging are eligible. Patients will undergo CTP at the time of first imaging on their hospital admission. Admission CTP compares with the reference standard of an accepted bedside clinical assessment for brainstem function. Deferred consent will be used. The primary outcome is a binary outcome of mortality (dead) or survival (not dead) in the first 48 hours of admission. The planned sample size for achieving a sensitivity of 75% and a specificity of 95% with a CI of ±5% is 200 patients., Ethics and Dissemination: This study has been approved by the University of Manitoba Health Research Ethics Board. The findings from our study will be disseminated through peer-reviewed journals and presentations at local rounds, national and international conferences. The public will be informed through forums at the end of the study., Trial Registration Number: NCT04318665., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2021. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Controlled donation after circulatory determination of death (DCD), where death is determined after cardiac arrest, has been responsible for the largest quantitative increase in Canadian organ donation and transplants, but not for heart transplants. Innovative international advances in DCD heart transplantation include direct procurement and perfusion (DPP) and normothermic regional perfusion (NRP). After death is determined, DPP involves removal and reanimation of the arrested heart on an ex situ organ perfusion system. Normothermic regional perfusion involves surgically interrupting (ligating the aortic arch vessels) brain blood flow after death determination, followed by restarting the heart and circulation in situ using extracorporeal membrane oxygenation. The objectives of this Canadian consensus building process by a multidisciplinary group of Canadian stakeholders were to review current evidence and international DCD heart experience, comparatively evaluate international protocols with existing Canadian medical, legal, and ethical practices, and to discuss implementation barriers. Review of current evidence and international experience of DCD heart donation (DPP and NRP) determined that DCD heart donation could be used to provide opportunities for more heart transplants in Canada, saving additional lives. Although candid discussion identified a number of potential barriers and challenges for implementing DCD heart donation in Canada, it was determined that DPP implementation is feasible (pending regulatory approval for the use of an ex situ perfusion device in humans) and in alignment with current medical guidelines for DCD. Nevertheless, further work is required to evaluate the consistency of NRP with current Canadian death determination policy and to ensure the absence of brain perfusion during this process.

Historically, there have been no manufacturers using Good Manufacturing Practices (GMP) to produce lentivirus in Canada, which has hampered gene therapy and CAR-T clinical programs in the country. The Ottawa Hospital recently developed a lentivirus manufacturing process using adherent cells in a flatware culture system, and used this process to produce sufficient amounts of clinical-grade lentivirus in a GMP manner for the Canadian CLIC-1901 CD19-CAR T Phase I/II clinical trial. While our previously established lentivirus manufacturing process used a flatware culture system, we plan to develop a larger-scale production process for clinical-grade lentivirus using the iCELLis bioreactor system. The iCELLis bioreactor system provides a large surface area for adherent cell growth, has a small physical footprint, and recently emerged as the leading scalable, single-use bioreactor technology for clinical manufacturing of viral vectors and vaccines. Our initial estimates suggest we could produce lentiviral vectors for approximately 2000 clinical doses for CAR-T cell therapy applications in a full-scale iCELLis 500+ bioreactor system; however, observed experimental titers in the first several iCELLis Nano batches were low. We hypothesized that this low titer was due to product instability in the bioreactor for long exposure times, and therefore implement a perfusion-based feeding system to remove product form the bioreactor for storage at more stable conditions. In this poster, we demonstrate that this perfusion strategy successfully resulted in bioreactor titers greater than the legacy flatware process for n=4 batches. [ABSTRACT FROM AUTHOR]

There is international variability in the determination of death. Death in donation after circulatory death (DCD) can be defined by the permanent cessation of brain circulation. Post-mortem interventions that restore brain perfusion should be prohibited as they invalidate the diagnosis of death. Retrieval teams should develop protocols that ensure the continued absence of brain perfusion during DCD organ recovery. In situ normothermic regional perfusion (NRP) or restarting the heart in the donor's body may interrupt the permanent cessation of brain perfusion because, theoretically, collateral circulations may restore it. We propose refinements to current protocols to monitor and exclude brain reperfusion during in situ NRP. In abdominal NRP, complete occlusion of the descending aorta prevents brain perfusion in most cases. Inserting a cannula in the ascending aorta identifies inadequate occlusion of the descending aorta or any collateral flow and diverts flow away from the brain. In thoracoabdominal NRP opening the aortic arch vessels to atmosphere allows collateral flow to be diverted away from the brain, maintaining the permanence standard for death and respecting the dead donor rule. We propose that these hypotheses are correct when using techniques that simultaneously occlude the descending aorta and open the aortic arch vessels to atmosphere., (© 2020 The Authors. American Journal of Transplantation published by Wiley Periodicals, Inc. on behalf of The American Society of Transplantation and the American Society of Transplant Surgeons.)

Objectives: The aim of this study was to investigate the impact of various brain perfusion techniques and nadir temperature cooling strategies on outcomes after aortic arch repair in a contemporary, multicentre cohort., Methods: A total of 2520 patients underwent aortic arch repair with hypothermic circulatory arrest (HCA) between 2002 and 2018 in 11 centres of the Canadian Thoracic Aortic Collaborative. Primary outcomes included mortality; stroke; a composite of mortality or stroke; and a Society of Thoracic Surgeons-defined composite (STS-COMP) end point for mortality or major morbidity including stroke, reoperation, renal failure, prolonged ventilation and deep sternal wound infection. Multivariable logistic regression and propensity score matching were performed for cerebral perfusion and nadir temperature practices., Results: Antegrade cerebral perfusion was found on multivariable analysis to be protective against mortality [odds ratio (OR) 0.64, 95% confidence interval (CI) 0.48-0.86; P = 0.005], stroke (OR 0.55, 95% CI 0.37-0.81; P = 0.006), composite of mortality or stroke (OR 0.57, 95% CI 0.45-0.72; P = 0.0001) and STS-COMP (OR 0.53, 95% CI 0.41-0.67; P < 0.0001), as compared to HCA alone. Retrograde cerebral perfusion yielded similar outcomes as compared to antegrade cerebral perfusion. When compared to HCA with nadir temperature <24°C, a propensity score analysis of 647 matched pairs identified nadir temperature ≥24°C as predictor of lower mortality (OR 0.62, 95% CI 0.40-0.98; P = 0.04), stroke (OR 0.51, 95% CI 0.31-0.84; P = 0.008), composite of mortality or stroke (OR 0.62, 95% CI 0.43-0.89; P = 0.01) and STS-COMP (OR 0.64, 95% CI 0.49-0.85; P = 0.002)., Conclusions: Antegrade cerebral perfusion and nadir temperature ≥24°C during HCA for aortic arch repair are predictors of improved survival and neurological outcomes., (© The Author(s) 2020. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.)