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OBJECTIVES The onset of the coronavirus disease 2019 (COVID-19) pandemic has forced our cardiac surgery programme and hospital to enact drastic measures that has forced us to change how we care for cardiac surgery patients, assist with COVID-19 care and enable support for the hospital in terms of physical resources, providers and resident training. METHODS In this review, we review the cardiovascular manifestations of COVID-19 and describe our system-wide adaptations to the pandemic, including the use of telemedicine, how a severe reduction in operative volume affected our programme, the process of redeployment of staff, repurposing of residents into specific task teams, the creation of operation room intensive care units, and the challenges that we faced in this process. RESULTS We offer a revised set of definitions of surgical priority during this pandemic and how this was applied to our system, followed by specific considerations in coronary/valve, aortic, heart failure and transplant surgery. Finally, we outline a path forward for cardiac surgery for the near future. CONCLUSIONS We recognize that individual programmes around the world will eventually face COVID-19 with varying levels of infection burden and different resources, and we hope this document can assist programmes to plan for the future.

BACKGROUND Mechanical stress caused by blood flow, such as wall shear stress (WSS) and its related parameters, is key moderator of endothelial degeneration. However, an in vivo method to measure WSS on heart valves has not been developed. METHODS We developed a novel approach, based on vector flow mapping using intraoperative epi-aortic echocardiogram, to measure WSS and oscillatory shear index (OSI) on the aortic valve. We prospectively enrolled 15 patients with normal valves, who underwent coronary artery bypass graft. RESULTS Systolic WSS on the ventricularis (2.40 ± 0.44 Pa [1.45-3.00 Pa]) was higher than systolic WSS on the fibrosa (0.33 ± 0.08 Pa [0.14-0.47 Pa], P

Cardiogenic shock and cardiac arrest due to acute coronary syndromes are almost exclusively approached, as first-line treatment, with percutaneous coronary intervention. In a few instances, however, coronary artery bypass grafting may be the procedure of choice or necessary in life-threatening scenarios based on the failure of percutaneous coronary intervention due to unfavourable/unsuitable anatomical features or for complications arising from percutaneous coronary intervention. Coronary artery bypass grafting in cardiogenic shock or cardiac arrest is frequently characterized by challenging and disadvantageous clinical and haemodynamic conditions.

Aims While mechanical stress caused by blood flow, e.g. wall shear stress (WSS), and related parameters, e.g. oscillatory shear index (OSI), are increasingly being recognized as key moderators of various cardiovascular diseases, studies on valves have been limited because of a lack of appropriate imaging modalities. We investigated the influence of aortic root geometry on WSS and OSI on the aortic valve (AV) leaflet. Methods and results We applied our novel approach of intraoperative epi-aortic echocardiogram to measure the haemodynamic parameters of WSS and OSI on the AV leaflet. Thirty-six patients were included, which included those who underwent valve-sparing aortic root replacement (VSARR) with no significant aortic regurgitation (n = 17) and coronary artery bypass graft (CABG) with normal AV (n = 19). At baseline, those who underwent VSARR had a higher systolic WSS (0.52 ± 0.12 vs. 0.32 ± 0.08 Pa, respectively, P < 0.001) and a higher OSI (0.37 ± 0.06 vs. 0.29 ± 0.04, respectively, P < 0.001) on the aortic side of the AV leaflet than those who underwent CABG. Multivariate regression analysis revealed that the size of the sinus of Valsalva had a significant association with WSS and OSI. Following VSARR, WSS and OSI values decreased significantly compared with the baseline values (WSS: 0.29 ± 0.12 Pa, P < 0.001; OSI: 0.26 ± 0.09, P < 0.001), and became comparable to the values in those who underwent CABG (WSS, P = 0.42; OSI, P = 0.15). Conclusions Mechanical stress on the AV gets altered in correlation with the size of the aortic root. An aneurysmal aortic root may expose the leaflet to abnormal fluid dynamics. The VSARR procedure appeared to reduce these abnormalities.

Valve sparing aortic root replacement remains a complex procedure despite various improvements that have been made to this operation. Specifically, a hemostatic proximal anastomosis is one of the most important factors for successful completion of the operation without complication. Here we describe a double mattress suture line technique, which facilitates a secure and hemostatic proximal suture line.

Primary graft failure (PGF) after heart transplantation (HT) is a devastating and unexpected event characterized by failure of the graft to adequately support recipient circulation necessitating high doses of vasopressors and inotropes and/or temporary mechanical circulatory support. Although it represents an increasingly common event in the current era, there remains a high degree of variability in prevalence, reported risk factors, and approach to this clinical entity. The purpose of the current review is to highlight preoperative considerations including known incidence and risk factors, perioperative issues involving the identification and management of PGF, and postoperative decisions related to weaning of mechanical circulatory support and titration of immunosuppressive therapy. Lastly, we highlight future directions in PGF research, involving basic and translational research, that have the potential to uncover novel strategies of risk stratification and treatment. CASE: Our patient is a 53-year-old man with end-stage non-ischemic dilated cardiomyopathy complicated by ventricular tachycardia (VT), post-capillary pulmonary hypertension, and renal insufficiency. After progressing to NYHA Class IV symptoms, he underwent implantation of a durable left ventricular assist device (LVAD) as bridge to transplant (BTT). On device support, he developed recurrent VT resulting in multiple defibrillator discharges and hospital admission for intravenous anti-arrhythmic therapy. He is subsequently upgraded to a higher status on the waiting list. A suitable donor is identified, with an appropriate predicted heart mass and an anticipated ischemic time of

Venoarterial extracorporeal membrane oxygenation is a useful treatment for severe primary graft dysfunction after heart transplant. The ideal timing of initiation is unknown.We retrospectively reviewed 362 adult heart transplant recipients at our center between January 2011 and December 2017. Thirty-eight patients (10.5%) experienced severe primary graft dysfunction treated with venoarterial extracorporeal membrane oxygenation. As our institution adopted a prompt venoarterial extracorporeal membrane oxygenation policy in 2015, patients were stratified into pre-2015 (conservative extracorporeal membrane oxygenation: n = 18) and post-2015 (prompt extracorporeal membrane oxygenation: n = 20) cohorts. Clinical outcomes were compared.Baseline characteristics were similar (conservative vs prompt) except for age (51.82 vs 59.96 years, P = .036), aspartate transaminase (32 vs 21.5 U/L, P = .038), male donor (44.4 vs 80%, P = .042), and donor ejection fraction (60 vs 65%, P = .047). Median ischemic time was significantly longer in the conservative extracorporeal membrane oxygenation cohort (210 vs 148 minutes, P = .005). Median time to initiation of extracorporeal membrane oxygenation was significantly shorter in the prompt extracorporeal membrane oxygenation cohort (7.26 vs 1.95 hours, P .0001). There was no difference in intensive care unit stay or major complications. In-hospital mortality improved from 28% (conservative) to 5% (prompt, P = .083). Post-transplant survival at 1 year was 67% in the conservative extracorporeal membrane oxygenation cohort and 90% in the prompt extracorporeal membrane oxygenation cohort (P = .117). There was no difference in the Kaplan-Meier survival curves (P = .071), although Cox regression suggested, but certainly did not prove, a 74.6% lower risk of mortality in the prompt extracorporeal membrane oxygenation group (P = .094).Prompt venoarterial extracorporeal membrane oxygenation use for primary graft dysfunction after heart transplant results in excellent myocardial recovery and a possible decrease in mortality without increased risk of complications.

Over the past several decades, techniques for surgery of the aortic arch have undergone significant evolution. In addition, there have been refinements in the mechanism of cerebral protection utilized intraoperatively. However, significant practice variations in the strategy of antegrade selective cerebral perfusion continue to persist. Here, we describe a simple and easily reproducible technique for selective antegrade cerebral perfusion, utilizing axillary cannulation and retrograde coronary sinus balloon catheters.

To assess the utility of full bowel preparation with oral nonabsorbable antibiotics in preventing infectious complications after elective colectomy.Bowel preparation before elective colectomy remains controversial. We hypothesize that mechanical bowel preparation with nonabsorbable oral antibiotics is associated with a decreased rate of postoperative infectious complications when compared with no bowel preparation.Patient and clinical data were obtained from the Michigan Surgical Quality Collaborative-Colectomy Best Practices Project. Propensity score analysis was used to match elective colectomy cases based on primary exposure variable-full bowel preparation (mechanical bowel preparation with nonabsorbable oral antibiotics) or no bowel preparation (neither mechanical bowel preparation given nor nonabsorbable oral antibiotic given). The primary outcomes for this study were occurrence of surgical site infection and Clostridium difficile colitis.In total, 2475 cases met the study criteria. Propensity analysis created 957 paired cases (n = 1914) differing only by the type of bowel preparation. Patients receiving full preparation were less likely to have any surgical site infection (5.0% vs 9.7%; P = 0.0001), organ space infection (1.6% vs 3.1%; P = 0.024), and superficial surgical site infection (3.0% vs 6.0%; P = 0.001). Patients receiving full preparation were also less likely to develop postoperative C difficile colitis (0.5% vs 1.8%, P = 0.01).In the state of Michigan, full bowel preparation is associated with decreased infectious complications after elective colectomy. Within this context, the Michigan Surgical Quality Collaborative recommends full bowel preparation before elective colectomy.

This chapter focuses on training pathways for cardiothoracic surgery and the pros and cons of traditional pathways, where trainees enter the specialty after completing general surgery residency, and integrated tracks where students match directly into cardiothoracic surgery out of medical school. We will examine why one pathway might be best for you as an individual, but want to emphasize that both pathways lead to successful training and a fruitful career and there is not one ‘best’ way to pursue cardiothoracic surgery.

Application of high-throughput transcriptome sequencing has spurred highly sensitive detection and discovery of gene fusions in cancer, but distinguishing potentially oncogenic fusions from random, “passenger” aberrations has proven challenging. Here we examine a distinctive group of gene fusions that involve genes present in the loci of chromosomal amplifications—a class of oncogenic aberrations that are widely prevalent in breast cancers. Integrative analysis of a panel of 14 breast cancer cell lines comparing gene fusions discovered by high-throughput transcriptome sequencing and genome-wide copy number aberrations assessed by array comparative genomic hybridization, led to the identification of 77 gene fusions, of which more than 60% were localized to amplicons including 17q12, 17q23, 20q13, chr8q, and others. Many of these fusions appeared to be recurrent or involved highly expressed oncogenic drivers, frequently fused with multiple different partners, but sometimes displaying loss of functional domains. As illustrative examples of the “amplicon-associated” gene fusions, we examined here a recurrent gene fusion involving the mediator of mammalian target of rapamycin signaling, RPS6KB1 kinase in BT-474, and the therapeutically important receptor tyrosine kinase EGFR in MDA-MB-468 breast cancer cell line. These gene fusions comprise a minor allelic fraction relative to the highly expressed full-length transcripts and encode chimera lacking the kinase domains, which do not impart dependence on the respective cells. Our study suggests that amplicon-associated gene fusions in breast cancer primarily represent a by-product of chromosomal amplifications, which constitutes a subset of passenger aberrations and should be factored accordingly during prioritization of gene fusion candidates.

Congenital anomalies of the aortic arch represent a diverse set of malformations with a common embryologic origin and a wide array of clinical manifestations. Arch anomalies are noted in 1–10/1,000 live births and account for approximately 15–20 % of all congenital heart disease (Hoffman and Kaplan, J Am Coll Cardiol 39:1890–1900, 2002). Presentation of aortic arch anomalies is highly variable with many patients remaining asymptomatic throughout life. When present, symptoms generally result from compression of surrounding mediastinal structures or associated intracardiac defects. Successful management of symptomatic arch anomalies often relies on surgical or endovascular intervention aimed at relieving compression or improving hemodynamics. In this review, we present several common aortic anomalies in correlation with their embryologic development and clinical features.

Pancreas ductal adenocarcinoma (PDAC) is a highly lethal cancer that typically presents as advanced, unresectable disease. This invasive tendency, coupled with intrinsic resistance to standard therapies and genome instability, are major contributors to poor long-term survival. The genetic elements governing the invasive propensity of PDAC have not been well elucidated. Here, in the course of validating resident genes in highly recurrent and focal amplifications in PDAC, we have identified Rio Kinase 3 (RIOK3) as an amplified gene that alters cytoskeletal architecture as well as promotes pancreatic ductal cell migration and invasion. We determined that RIOK3 promotes its invasive activities through activation of the small G protein, Rac. This genomic and functional link to Rac signaling prompted a genome wide survey of other components of the Rho family network, revealing p21 Activated Kinase 4 (PAK4) as another amplified gene in PDAC tumors and cell lines. Like RIOK3, PAK4 promotes pancreas ductal cell motility and invasion. Together, the genomic and functional profiles establish the Rho family GTP-binding proteins as integral to the hallmark invasive nature of this lethal disease.