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In an effort to further improve surgical outcomes in patients with acute type A aortic dissection (ATAD), the Canadian Thoracic Aortic Collaborative (CTAC), with the support of the Canadian Society of Cardiac Surgeons (CSCS), endeavored to develop quality indicators (QIs) for the management of patients with ATAD. After two successive consultations with the CTAC membership, 11 QIs were selected and separated into 5 broad categories: pre-operative (time from presentation to diagnosis, time from presentation to the operating room), intra-operative (use of hypothermic circulatory arrest and antegrade cerebral perfusion), 30-day outcomes (30-day rates of all-cause mortality, 30-day rates of new post-operative stroke), 1-year outcomes (1-year rates of follow-up imaging, 1-year rates of all-cause mortality, and 1-year rates of surgical re-intervention), and institutional (institutional surgical volumes, individual surgical volumes and presence of institutional aortic disease teams). The purpose of this manuscript was to describe the process by which QIs for the management of ATAD were developed and the feasibility by which they may be collected using existing clinical and administrative data sources. Furthermore, we demonstrate how they may be used to evaluate success following surgery for repair of ATAD and ultimately improve clinical outcomes.

The New Brunswick Heart Centre (NBHC) entered a contractual partnership with Integrated Health Solutions (IHS) to help address increasing wait times in the province of New Brunswick.Team leaders were identified from each of the target areas, including surgeons, anesthesiologists, nurses (operating room, intensive care unit [ICU] and postoperative ward), access coordinators and administrators. The methodology used was based on Lean principles and involved exercises by stakeholders aimed at identifying opportunities for improvement. A weekly dashboard was created to monitor and facilitate improvement efforts. No additional hospital beds or operating room theatres were added during the study period.After 2 years, the annual number of cardiac surgical interventions increased from 788 to 873, representing a 10.8% increase in capacity. The best median wait time for patients decreased from 52 to 35 days (35% reduction). The best 90th percentile wait time decreased from 126 to 98 days (22% reduction). The overall increase in capacity could be explained in part by the significant increase in fast tracking from the ICU to the ward (2-fold) or bypassing the ICU altogether (4-fold increase reaching 13%). Despite these successes, challenges persist as the number of OR cancellations remained around 7.5% of all cases, mainly because of limited ICU resources.The NBHC-IHS partnership on this project has resulted in excellent engagement by stakeholders and promoted team cohesiveness. Furthermore, it has allowed significant reorganization and realignment of efforts to limit wait times and maximize overall capacity.Le New-Brunswick Heart Centre (NBHC) a conclu une entente contractuelle avec Integrated Health Solutions (IHS) pour remédier aux temps d’attente de plus en plus longs au Nouveau-Brunswick.Des chefs d’équipe ont été identifiés pour chaque domaine cible, notamment la chirurgie, l’anesthésie, les soins infirmiers (en salle d’opération, aux soins intensifs et en soins postopératoires), la coordination des soins et la direction. La méthodologie utilisée se fondait sur l’approche Lean et comprenait des exercices visant à relever les possibilités d’amélioration. Un tableau de bord hebdomadaire a été créé pour suivre et faciliter les mesures d’amélioration. On n’a ajouté aucun lit d’hôpital et aucune salle d’opération pendant la période étudiée.Après 2 ans, le nombre de chirurgies cardiaques par année est passé de 788 à 873, une augmentation de 10,8 % de la capacité. Le temps d’attente médian pour les patients est tombé de 52 à 35 jours (réduction de 35 %). Le temps d’attente au 90e centile est passé de 126 à 98 jours (réduction de 22 %). L’augmentation générale de la capacité peut s’expliquer en partie par la réduction significative du temps passé aux soins intensifs avant l’admission en soins généraux (2 fois) ou par l’élimination complète du passage aux soins intensifs (augmentation de 400 %; 13 % des cas). Malgré ces réussites, des défis demeurent puisque le taux d’annulation des interventions est resté autour de 7,5 % des cas, surtout en raison des ressources limitées aux soins intensifs.Le partenariat NBHC–IHS sur ce projet a permis de mobiliser efficacement les participants et a favorisé la cohésion au sein de l’équipe. Il a en outre permis une importante réorganisation des ressources pour réduire les temps d’attente et augmenter la capacité générale.

OBJECTIVES Long-term quality of life following open surgical valve replacement is an increasingly important outcome to patients and their caregivers. This study examines non-institutionalized survival and rehospitalization within our surgical aortic valve replacement (AVR) and mitral valve replacement (MVR) populations. METHODS A retrospective single-centre study of all consecutive open surgical valve replacements between 1995 and 2014 was undertaken. Clinical data were linked to provincial administrative data for 3219 patients who underwent AVR, MVR or double (aortic and mitral) valve replacement with or without concomitant coronary artery bypass grafting (CABG). Non-institutionalized survival and cumulative incidence of rehospitalization was examined up to 15 years. RESULTS Follow-up was complete for 96.9% of the 2146 patients who underwent AVR ± CABG (66.7% of the overall cohort), 878 who underwent MVR ± CABG (27.3%) and 195 who underwent double (aortic and mitral) valve replacement ± CABG (6.0%) with a median follow-up time of 5.6 years. Overall non-institutionalized survival was 35.4% at 15 years, and the cumulative incidence of rehospitalization was 34.4%, 63.2% and 87.0% at 1, 5 and 15 years, respectively, without significant differences between valve procedure cohorts. Both non-institutionalized survival and cumulative incidence of rehospitalization improved in more recent eras, despite increasing age and comorbidities. CONCLUSIONS Non-institutionalized survival and rehospitalization data for up to 15 years suggest good functional outcomes long after surgical AVR and/or MVR. Continued improvements are seen in these metrics over the past 2 decades. This provides a unique insight into the quality of life after surgical valve replacement in the ageing demographics with valvular heart disease.

BACKGROUND The standard of care for patients with aortic stenosis has evolved significantly in recent years with transcatheter aortic valve implantation (TAVR) shown to be a safe alternative to surgical aortic valve replacement (SAVR). Concerns remain as to the durability of TAVR valves and factors that may affect that durability. The objective of this study was to look at valve performance using echocardiography to assess for early structural valve deterioration. METHODS AND RESULTS All patients undergoing successful TAVR implantation between 2010 and 2018 were included in the study. Standard follow-up echocardiograms were performed before the procedure in addition to immediately post procedure and at: 6 weeks, 6 months, 1 year, and every year subsequently. Structural valve deterioration or failure was defined as a mean aortic valve gradient of >20mmHg after implantation. Using this approach, we divided patients into 2 groups: no evidence of valve deterioration versus any evidence of valve deterioration by ECHO. A total of 406 patients were included with balloon expandable (n=335) and self-expandable valves (n=57). Valve deterioration defined as a mean gradient >20mmHg was observed in 82 patients at any point during follow-up. Risk factors associated with valve deterioration were increased BMI (p=0.004), previous prosthetic valve (p=0.0001), older age (p=0.02), and female sex (p=0.02). Valves that developed mean gradients over 20mmHg were more likely to have had higher pre-TAVR gradients (p=0.007). Failure rates were low early after procedure (8% of patients). The relative failure rate increased to 24% of patients by year three. In patients showing gradients >20mmHg gradients appears to gradually increase as shown in the figure below. Even though there is variance in the initial year among valves (p=0.53), at two years and every year subsequently, there is no significant difference in valve gradient between self-expanding and balloon-expanding valves. CONCLUSION Our data demonstrates that TAVR valves provide a significant reduction in mean gradient across the aortic valve after deployment. Using follow-up echocardiography, we were able to demonstrate that some patients develop increasing mean gradients over time with up to 24% of patients by 3-year follow-up having some early structural valve deterioration. We identified several factors that were associated with higher gradients at follow-up and may warrant closer follow-up.

BACKGROUND Transcatheter aortic valve replacement (TAVR) has become an established treatment for patients suffering with aortic stenosis. However, there remains some uncertainty on the risk factors associated with TAVR and conduction disturbances requiring permanent pacemaker insertion (PPI) following the procedure. The aim of this study was to identify risk factors for post-TAVR pacemaker need and examine the effect of PPI on long-term outcomes. METHODS AND RESULTS A retrospective study was performed on all consecutive patients who underwent TAVR at the Saint John Regional Hospital between 2010-2018, excluding those with an existing pacemaker. Risk factors capable of independently predicting post-procedure PPI were identified using two-tailed t-test, χ-square test, and hierarchical logistic regression model. Kaplan-Meier survival analysis was performed to compare all-cause mortality between patients who did or did not receive a pacemaker. A total of 377 patients with no previous pacemaker were included in the study. A total of 42 (11.1%) required PPI post-TAVR and were compared to patients who did not. Univariate analysis suggested that larger valves (>29cm) (p=0.05), renal insufficiency (p=0.03), and ECG abnormalities (p 200ms (p=0.0003), and heart rate CONCLUSION Our study illustrates that permanent pacemaker use in TAVR remains high (>10%) and identifies several ECG abnormalities as the most robust predictors of pacemaker need post-TAVR, in particular RBBB. However, our limited study suggests that post-TAVR pacemaker insertion is not associated with all-cause mortality after discharge. As TAVR becomes a treatment option for lower surgical risk patients, considerations for the need for post-procedural pacemaker insertion may affect clinical decision making and warrant screening for conduction abnormalities in patients undergoing TAVR.

Objectives Despite two decades of experience, no dedicated classification system exists to document and prognosticate patterns of endoleak encountered after endovascular therapy of type-B aortic dissection. This nomenclature gap has led to inconsistent management and underreporting of significant findings associated with adverse outcomes after endovascular treatment of type-B aortic dissection. Our goal was to propose a reproducible and prognostically relevant classification. Methods A multidisciplinary team of seven experienced open and endovascular aortic surgeons was assembled to provide consensus opinion. Extensive literature review was conducted. Deficiencies in the current classification approach of the various patterns of persistent filling of false lumen after endovascular therapy were identified. Results Our focus was to categorize high-risk and low-risk subgroups within endoleaks after endovascular treatment of type-B aortic dissection. In this classification, type-Ia endoleak refers to persistent filling of the false lumen in an antegrade manner. Causes include failure to cover the primary entry tear and sizing or technical related proximal seal failure. False lumen filling via distal entry tears is classified as type Ib endoleak, which is further sub-classified into b1 (major branch-related tears), and b2 (multiple small branches related tears). Retrograde ascending aortic dissection and stent graft-induced new entry were classified as type-I endoleaks (type-Ir and type-Is, respectively). Another focus was reclassification type-II endoleaks, with type-IIa endoleak referring to conventional retroleak from one or more posterior branches and type-IIx referring to retroleak from major branches (visceral or left subclavian arteries). Conclusions The majority of endoleaks after endovascular treatment of type-B aortic dissection are related to persistent or new filling of the false lumen. We propose a new false lumen-based classification schema for endoleaks occurring after endovascular therapy of type-B aortic dissection.

Background Hybrid aortic arch surgery has evolved to include several technical variations, with most including an off-label use of a conventional thoracic endograft. We describe the early clinical outcomes of the Thoraflex Hybrid graft (Vascutek, Glasgow, Scotland) specifically designed for the treatment of complex arch and proximal descending aortic disease. Methods Between January 2014 and April 2017, 40 consecutive patients (66 ± 14 years of age, 45% women) underwent hybrid aortic arch and frozen elephant trunk repair with the multibranched Thoraflex Hybrid graft at 9 Canadian centers. Surgical indications included transverse arch or proximal descending aortic aneurysm in 100%, acute dissection in 10%, chronic dissection in 43%, and acute aortic rupture in 1 patient. Antegrade cerebral perfusion and moderate hypothermia (24.3 ± 1.8°C) were employed in all cases. Results All 40 device implants were successful. The 30-day or in-hospital mortality was 5%. Stroke and transient neurological deficits occurred in 5% and 3% of patients, respectively. Two (5%) patients experienced transient spinal cord ischemia—there were no instances of permanent paraplegia. Mean follow-up was 550 ± 328 days and late complications included type A aortic dissection in 1 patient, type B dissection in 2 patients, and further distal endografting in 2 patients. Survival at 30 days, 1 year, and 2 years was 95%, 95%, and 90%, respectively. Conclusions Hybrid aortic arch and frozen elephant trunk repair with the Thoraflex Hybrid graft appears to be associated with good clinical outcomes, despite being early in the learning curve with this graft. Further investigation with this device is warranted to establish its role within the variations of hybrid arch repair.

Acute type A aortic dissections still present a major challenge to cardiac surgeons. Although surgical management remains the gold standard, operative mortality remains high, including in experienced centres. Nevertheless, recent advances in the understanding and management of various aspects of these complex operations are expected to improve overall patient outcomes. The Canadian Thoracic Aortic Collaborative (CTAC) represents a group of surgeons with interest and expertise in the management of patients with aortic diseases. The purpose of this state-of-the-art review is to detail our approach to the contemporary surgical management of acute type A aortic dissections. We focus specifically on cannulation strategies, cerebral protection, and extent of proximal and distal resection. In addition, specific clinical scenarios-including malperfusion, intramural hematomas, and surgery in octogenarians-are explored.

Originally conceived of as a means for bridging patients to heart transplantation, the encouraging long-term outcomes of left ventricular assist devices (LVADs) have led to their increased use in the treatment of heart failure, even in cases where transplant candidacy or availability is unlikely. Despite the life-saving aspects of LVAD therapy to support the patient with end-stage heart failure, issues of pump obstruction and thrombosis persist, resulting in an increasing need for emergent device exchanges or deaths from thrombosis.1 This forms a diagnostic dilemma for care providers because there are a variety of clinical syndromes that may mimic this feared complication, yet the treatment options for bona fide pump thrombosis are limited. Although algorithms have been proposed to address this problem in a standardized fashion,2 there remains considerable heterogeneity in the diagnosis and management of pump thrombosis between centers. Where outflow graft obstruction is suspected, vascular ultrasound has previously been used intraoperatively to confirm the presence of outflow graft obstruction.3 However, intravascular ultrasound (IVUS) offers the benefit of confirming obstruction before taking the patient to the operating suite for device exchange. We present a case of HeartMate II LVAD (Thoratec Corporation, CA) thrombosis in which IVUS was used in this very manner; the first reported case of its kind. A 65-year-old female (62 kg) with …

Background: Surgery confers the best chance of survival following acute Type A dissection (ATAD), yet perioperative mortality remains high. Although perioperative risk factors for mortality have been described, information on the actual causes of death is sparse. In this study, we aimed to characterize the inciting events causing death during surgical repair of ATAD. Methods: Nine centers participated in the study. We included all patients who died following surgical repair for ATAD between January 2007 and December 2013. An aortic surgeon at each site determined the primary cause of death from seven predetermined categories: cardiac, stroke, hemorrhage, other organ ischemia (peripheral, renal, or visceral), multiorgan failure, sepsis, or other causes. Additional characteristics and variables were analyzed to delineate potential modifiable factors for mortality. Results: Of the 692 surgeries for ATAD, there were 123 deaths (17.8% mortality rate). Mean age at death was 66 years. Events contributing to death were: cardiac (25%), stroke (22%), hemorrhage (21%), multiorgan failure (12%), other organ ischemia (11%), sepsis (4%), and other causes (5%). Neurologic injury at presentation was a predictor of stroke as the inciting cause of death (p = 0.04). Peripheral, renal, or visceral ischemia at presentation was highly predictive of death due to these presenting ischemic conditions (p = 0.004). We found no associations between cardiogenic shock, tamponade, or cardiopulmonary bypass duration and cardiac death. Conclusion: Operative mortality for ATAD remains high in Canada. Nearly 70% of deaths arise from cardiac failure, stroke, or hemorrhage. Therefore, novel surgical, hybrid, and endovascular strategies should target these three areas.

Management of cardiac surgery health human resources (HHR) has been challenging, with recent graduates struggling to secure employment and a shortage of cardiac surgeons predicted as early as 2020. The length of cardiac surgery training prevents HHR supply from adapting in a timely fashion to changes in demand, resulting in a critical need for active workforce management. This study details the results of the 2015 Canadian Society of Cardiac Surgeons (CSCS) workforce survey undertaken as part of the CSCS strategy for active workforce management. The 38-question survey was administered electronically to all 96 trainees identified as being registered in a Canadian cardiac surgery residency program for the 2015-2016 academic year. Eighty-four of 96 (88%) trainees responded. The majority of participants were satisfied with their training experience. However, 29% stated that their clinical and operative exposure needed improvement, and 57% of graduating trainees did not believe that they would be competent to practice independently at the conclusion of their training. Although 51% of participants believe the job market is improving, 94% of senior trainees found it competitive or extremely difficult to secure an attending staff position. Participants highlighted a need for improved career counselling and formal mentorship. Although the job market is perceived to be improving, a mismatch in the cardiac surgery workforce supply and demand remains because current trainees continue to experience difficulty securing employment after the completion of residency training. Trainees have identified improved career counselling and mentorship as potential strategies to aid graduates in securing employment.

Background Endovascular options to repair the arch and ascending aorta are rapidly evolving. Little is known about the durability of endovascular devices deployed at this location. This report describes a single-centre experience with the novel application of thoracic endovascular aortic repair (TEVAR) by examining clinical and radiological outcomes. Methods A retrospective review was performed for a cohort of patients undergoing TEVAR of the arch or ascending aorta, or both, at a single centre from November 2008-July 2012. Results Sixteen patients were included in the study, with mean imaging follow-up of 38 months (range, 15-72 months). Two complications at the proximal landing zone in the ascending aorta were identified: 1 endoleak and 1 infolding identified at 3 and 24 months postoperatively, respectively. Clinically, both these complications were attributed to the bird-beak configuration at the proximal landing zone site. At up to 72 months of follow-up, there were no cases of retrograde dissection of the native sinus of Valsalva. There were no cases of stent graft migration, graft fracture, open surgical reintervention for aortic pathologic conditions, or late mortality. Conclusions Early outcomes suggest that the current generation of thoracic aortic endografts can be placed in the complex anatomy of the ascending aorta and aortic arch without a high incidence of early graft fracture or migration. Future endeavors will need to focus on techniques to achieve optimal apposition with the curves of the ascending aorta. These findings are important as indications for endovascular aortic therapies expand to address proximal aortic pathologic conditions.

The between-day repeatability of simultaneous measures of brachial artery diameter (D) (echo Doppler) and mean blood velocity (MBV) (pulsed Doppler) was tested during rest and exercise. On 3 separate days, six volunteers performed one trial of 1-min rest followed by a step increase in dynamic handgrip exercise for 4 min which required the lifting and lowering of a 4.4-kg weight (approximately 8-12% MVC) in a 1s/2s (work/rest) cadence. Measures for MBV and D were collected continuously on a beat-by-beat basis during the transition from rest to end exercise. The mean rest values over one min, and single data points at 30, 60, 120, and 240 s of exercise were extracted from the time series data. At all exercise time points, MBV was greater than rest (P0.05), but these levels were not different across test days. Arterial D at all exercise time points ranged from 3.8 +/- 0.1 mm to 4.1 +/- 0.1 mm (mean +/- SEM) and did not differ from rest (3.9 +/- 0.1 mm) (P0.05), nor did D differ between days. The mean between-day coefficient of variation for D was 4.08 +/- 0.7% at rest and ranged from 2.90 +/- 0.4% to 3.96 +/- 0.5% during exercise. The coefficient of variation for MBV was 13.2 +/- 2.6% at rest and reached 20.2 +/- 3.1% during the final min of exercise; the exercise variability was reduced to 14.9 +/- 2.4% by averaging MBV over 3 s (the duration of a contraction/relaxation duty cycle) (P0.05) with no further advantage of averaging over ten 60-s sample periods. The data indicate that, for the six subjects tested, Doppler ultrasound measures of arterial MBV and diameter during both rest and exercise were reproducible across different test days and can be used as a reliable, noninvasive means of testing hypotheses pertaining to blood flow control.

Nucleoside transporters (NTs) are integral membrane transport proteins that modulate the flux of nucleosides such as adenosine across cell membranes. Two families of NTs exist, the concentrative NTs (CNTs, SLC28) and the equilibrative NTs (ENTs, SLC29). CNTs and ENTs transport anti-cancer and anti-viral nucleoside analog drugs and ENTs are also targets of drugs used to treat cardiac pathologies. Levels of some NT profiles have been shown to relate to clinical outcomes in the use of nucleoside analog drugs. However, currently, patient NT profile is not assessed prior to pharmacological administration of analog drugs. Here we describe a reliable method to determine a complete individual NT expression profile from human tissue using quantitative real-time PCR. We developed this assay on tissue (right atrial appendage, left internal mammary, aorta) from individuals undergoing cardiac surgery and compared these findings to the NT expression profiles in pooled whole heart tissue (normal and diseased). Data show that hENT1 is the most abundantly expressed NT, with highest expression levels in the aorta. However, NT expression profiles are highly variable among individuals and changes in NT expression between normal and diseased tissues were observed. These data are the first to describe the RNA expression patterns of all seven NT isoforms in the human heart. The methodology described here may be useful for quantitatively characterizing complete NT expression profiles in any human target tissue.

Objectives The complexity of surgical treatment for acute type A dissection contributes to the variability in patient management. This study was designed to elucidate the contemporary practice preferences of cardiac surgeons regarding different phases of management of acute type A aortic dissection. Methods A 34-item questionnaire was distributed to all Canadian adult cardiac surgeons addressing the preoperative, intraoperative, and postoperative management of acute type A dissection. A total of 100 responses were obtained (82% of active surgeons in Canada). Outcomes were compared between high- and low-volume aortic surgeons. Results Seventy-six percent of respondents favored axillary artery cannulation. High-volume surgeons (>150 cases) were more likely to indicate a target lowest nasopharyngeal temperature more than 20°C (53% vs 25%, P = .02). The majority of surgeons (65%) recommended using selective antegrade cerebral perfusion, with a significantly greater proportion for higher-volume aortic surgeons ( P = .03). In addition, high-volume aortic surgeons were more likely to recommend aortic root replacement at smaller diameters (73% vs 55%, P = .02), to recommend more extensive distal aortic resection with routine open hemiarch anastomosis (85% vs 65%, P = .04), and to more commonly perform total arch reconstruction when needed (93% vs 77%, P = .04). In the follow-up period, frequency of serial imaging of the residual aorta was significantly higher for high-volume aortic surgeons ( P = .04). Conclusions This study identified some commonalities in practice preferences among Canadian cardiac surgeons for the management of acute type A aortic dissection. However, it also highlighted significant differences in temperature management, cerebral protection strategies, and extent of resection between high-volume and low-volume aortic surgeons.