Early outcomes of endovascular repairs of the aortic arch using thoracic branch endoprosthesis.

OBJECTIVE: The only commercially available thoracic branched endoprosthesis (TBE) for treatment of the aortic arch was released in 2022. Limited data outside of clinical trial results have been reported. This study describes the demographics, anatomic details, and outcomes for patients treated for zone 0 to 2 using TBEs outside of a clinical trial. METHODS: All patients treated using TBEs for zone 0 to 2 were included. Patients treated as part of the clinical trial for zone 0 to 1 (n = 6) were excluded. Patient demographics, comorbidities, anatomic and operative details, and outcomes were reported. Outcomes and survival were then compared between groups. RESULTS: Of 40 patients, six patients underwent repair of zone 0, three of zone 1, and 31 of zone 2. There were no differences in demographics, comorbidities, or operative details by zone of treatment; however, the frequency of genetic aortopathy differed (zone 0: 0%; zone 1: 67%; and zone 2: 6.4%; P < .01). Seventy-three percent of patients were treated for dissection vs 27% with isolated aneurysms. Of the patients, 2.5% were treated for rupture, 22% were treated for symptomatic aneurysms, and 75% were treated electively. Forty-eight percent of repairs included a proximal cuff, and 83% received distal extension. Technical success was achieved in 100% of patients. Mean fluoroscopy time was 18 minutes, and median fluoroscopy dose was 416 mGy. Sixty percent of patients had prior aortic ascending/arch repair. TBE was planned as part of a complete thoracoabdominal repair in 45% of patients. Thirty-day mortality was 2.5% overall, with a single death in a zone 0 patient that occurred at day 1 due to a myocardial infarction. There were no reinterventions within 30 days. All other outcomes were similar. The 30-day stroke rate was 5.0%. The strokes occurred at day 6 (zone 1) and day 15 (zone 2); however, both were due to occlusion of a prior proximal surgical bypass and unrelated to the TBE side branch or embolization. Specifically, both patients had occlusion of a branch of their prior zone 1 or zone 2 arch replacement. An endoleak occurred in 7.5% of patients at 30-day follow-up (type II: 5.0%; unknown: 2.5%). At a mean follow-up of 6.6 months, 100% of side branches were patent. CONCLUSIONS: Repair of the aortic arch including TBE can be performed electively and urgently with acceptable stroke and death rates. TBE provides a valuable tool for patients requiring complete repair of a thoracoabdominal aneurysm. Continued investigation is underway to assess long-term safety and efficacy outside of the clinical trial.

A novel in vivo assessment of fluid dynamics on aortic valve leaflet using epi-aortic echocardiogram.

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 < .001) and diastolic WSS on the ventricularis (0.18 ± 0.07 Pa [0.04-0.28 Pa], P < .001). Oscillatory shear index on the fibrosa was higher than on the ventricularis (0.29 ± 0.04 [0.24-0.36] vs 0.05 ± 0.03 [0.01-0.12], P < .001). A pilot study involving two patients with severe aortic regurgitation showed significantly different values in fluid dynamics. CONCLUSION: Vector flow mapping method using intraoperative epi-aortic echocardiogram is an effective way of measuring WSS and OSI on normal aortic leaflet in vivo, allowing for better understanding of the pathophysiology of aortic valve diseases.

Management of primary graft failure after heart transplantation: Preoperative risks, perioperative events, and postoperative decisions.

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 <4 hours. He is taken to the operating room, where at the time of anesthesia induction he develops vasodilatory shock, requiring high-dose vasopressors, and cardiopulmonary bypass (CPB) support for dissection. After surgical anastomosis, cross clamp removal and reperfusion, graft function is extremely poor, there is significant bradycardia requiring pacing, and the patient is unable to be weaned successfully from CPB. Venoarterial extracorporeal membrane oxygenation (VA-ECMO) is initiated, and the patient is transferred to the intensive care unit. Retrospective flow crossmatch is negative. This patient is suffering from severe primary graft failure.

Double mattress suture lines for valve-sparing aortic root replacement.

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.

A statewide colectomy experience: the role of full bowel preparation in preventing surgical site infection.

OBJECTIVE: To assess the utility of full bowel preparation with oral nonabsorbable antibiotics in preventing infectious complications after elective colectomy. BACKGROUND: 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. METHODS: 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. RESULTS: 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). CONCLUSIONS: 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.

Elective root replacement increases the risk of type B dissection in patients with Marfan syndrome.

OBJECTIVE: Marfan syndrome is a genetic disorder with increased risk of aortic dissection. Currently, type A aortic dissection risk is mitigated by aortic root replacement with Dacron. It is unclear if root replacement increases the risk of distal aortic disease given the noncompliant nature of Dacron. METHODS: All adult patients with a diagnosis of Marfan syndrome at a single academic center, excluding those with history of dissection or concomitant arch repair, were studied (n = 322). Student t test or Wilcoxon Mann-Whitney test was used for continuous variables; chi-square or Fisher exact test was used for categorical variables. Propensity matching used age, sex, hypertension, race, body mass index, family history of Marfan syndrome, and genetic mutational class. Differences in freedom from type B aortic dissection were determined using the log-rank test. RESULTS: A total of 124 patients underwent root replacement compared with 198 patients with no prior aortic surgery. Median follow-up time was 9.90 years. Male sex, weight, and hypertension prevalence were higher in the root replacement group (P < .05). Distribution of fibrillin-1 mutations was homogenous (P > .9). Type B aortic dissection frequency in the root replacement group was higher (21% [n = 20] vs 4.2% [n = 4], P < .001). Aortic-related mortality was higher in the root replacement group (11% [n = 14] vs 3.5% [n = 7], P < .01). Distal aortic intervention frequency was higher in the root replacement group (P = .009). CONCLUSIONS: Patients with Marfan syndrome who undergo elective aortic root replacement appear to have a higher incidence of subsequent type B aortic dissection, independent of other risk factors. Careful consideration must be made to the management of the distal aorta in patients with Marfan syndrome who undergo root replacement.

Multidisciplinary hybrid approach to management of a thoracoabdominal aneurysm in a patient with both Loeys-Dietz and vascular Ehlers-Danlos syndrome.

Loeys-Dietz syndrome and vascular Ehlers-Danlos syndrome are genetic aortopathies that result from abnormal collagen matrix formation associated with vascular complications and early death. Identification of simultaneous COL3A1 and SMAD3 mutations as well as subsequent open and endovascular repair have not been reported. We present a case of a staged complete aortic replacement in a patient with a 7-cm aneurysm of his aortic arch and confirmed genetic mutations for Loeys-Dietz syndrome and vascular Ehlers-Danlos syndrome. This case highlights that, despite increased operative risk, successful staged repair of the entire aorta can be achieved in a patient with multiple severe genetic aortopathies.

Dissemination and implementation analysis of the Ross procedure in adults: time to update the guidelines?

Background: The science of dissemination and implementation (D&I) aims to improve the quality and effectiveness of care by addressing the challenges of incorporating research and evidence-based practice into routine clinical practice. This lens of D&I has challenged the interpretation and incorporation of data, noting that failure of a given therapy may not reflect lack of efficacy, but instead reflect an imperfect implementation. The aim of this manuscript is to review the influence of the Ross procedure's historical context on its D&I. Methods: A contextual baseline of the Ross procedure was defined from the procedure's original description in the literature to major publications since the 2017 valvular heart disease guidelines. D&I evaluation was conducted using the Consolidated Framework for Implementation Research (CFIR), using constructs from each of the five respective domains to define the main determinants. Results: Each of the five CFIR domains appears to be correlated with a factor influencing the Ross procedure's varied history of enthusiasm and acceptance. The complex nature of Ross required adaptation for optimization, with a strong correlation of center volume on outcomes that were not considered in non-contemporary studies. Outcomes later published from those studies influenced social and cultural contexts within the aortic surgery community, and led to further organizational uncertainty, resulting in slow guideline incorporation. Conclusions: The D&I of the Ross procedure was a result of inadequate appreciation of technical complexity, effect of patient selection, and complex aortic surgery experience, resulting in dismissal of an efficacious procedure due to a misunderstanding of effectiveness.

Natural history of the distal aorta following elective root replacement in patients with Marfan syndrome.

OBJECTIVE: It is unclear if the addition of a prophylactic arch operation is beneficial at the time of root replacement in patients with Marfan syndrome (MFS). This project aims to understand the fate of the distal aorta following elective root replacement in patients with MFS. METHODS: Between 2000 and 2019, 124 adult patients with MFS were identified as having undergone elective aortic root replacement with a clamped distal aortic anastomosis during their lifetime. Serial axial imaging was analyzed. The primary outcome was a composite of subsequent type B aortic dissection (TBAD), aneurysmal degeneration (>4 cm), and aortic reintervention. Secondary outcomes included subsequent TBAD and mortality. RESULTS: Mean age at root replacement was 33.3 years. Median follow-up was 11.3 years. Thirty-one patients (25%) experienced the primary outcome, with no survival difference (P = .9). The crossclamp and aortic cannulation sites were stable (growth rate, 0.33 mm/year), and 2 patients (1.6%) required reintervention there. Twenty-three patients (19.8%) experienced subsequent TBAD. Patients with TBAD had a higher rate of distal degeneration (P < .001), but no significant change in survival (P = .2). Preoperative hypertension (odds ratio, 3.96; P < .05) and younger age at root replacement (odds ratio, 1.05; P < .05) increased the risk of TBAD, based on regression analysis. CONCLUSIONS: The distal aorta (including the clamp and cannulation site) overall appears stable in patients with MFS following elective root replacement without prophylactic arch operation. Development of TBAD seems to be the primary driver of distal degeneration. Factors associated with TBAD development included hypertension, underscoring the importance of strict blood pressure control in these patients.

In-Human Implantation of a Novel Biologic Valved Conduit for Aortic Root Replacement.

Aortic root replacement is a complex procedure. Recently, the KONECT RESILIA aortic valved conduit (Edwards Lifesciences, Irvine, CA), the first prefabricated biologic valved conduit available in the United States, was approved for use. Here, we report a series of 3 patients representing implantation of the novel Konect AVC. The conduit was implanted in both supraannular and intraannular positions, and the unique design of the sewing ring offers several advantages. The Konect AVC streamlines the process of root replacement and may represent an improvement in terms of ease of implantation and durability.

BCR-ABL promotes the frequency of mutagenic single-strand annealing DNA repair.

Intracellular oxidative stress in cells transformed by the BCR-ABL oncogene is associated with increased DNA double-strand breaks. Imprecise repair of these breaks can result in the accumulation of mutations, leading to therapy-related drug resistance and disease progression. Using several BCR-ABL model systems, we found that BCR-ABL specifically promotes the repair of double-strand breaks through single-strand annealing (SSA), a mutagenic pathway that involves sequence repeats. Moreover, our results suggest that mutagenic SSA repair can be regulated through the interplay between BCR-ABL and extrinsic growth factors. Increased SSA activity required Y177 in BCR-ABL, as well as a functional PI3K and Ras pathway downstream of this site. Furthermore, our data hint at a common pathway for DSB repair whereby BCR-ABL, Tel-ABL, Tel-PDGFR, FLT3-ITD, and Jak2V617F all increase mutagenic repair. This increase in SSA may not be sufficiently suppressed by tyrosine kinase inhibitors in the stromal microenvironment. Therefore, drugs that target growth factor receptor signaling represent potential therapeutic agents to combat tyrosine kinase-induced genomic instability.

Genomic alterations link Rho family of GTPases to the highly invasive phenotype of pancreas cancer.

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.

Influence of aneurysmal aortic root geometry on mechanical stress to the aortic valve leaflet.

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.

The rapid transformation of cardiac surgery practice in the coronavirus disease 2019 (COVID-19) pandemic: Insights and clinical strategies from a center at the epicenter.

BACKGROUND: The onset of the coronavirus disease 2019 (COVID-19) pandemic has forced our cardiac surgery program 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 program, 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 programs around the world will eventually face COVID-19 with varying levels of infection burden and different resources, and we hope this document can assist programs to plan for the future.

The rapid transformation of cardiac surgery practice in the coronavirus disease 2019 (COVID-19) pandemic: insights and clinical strategies from a centre at the epicentre.

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.

The Rapid Transformation of Cardiac Surgery Practice in the Coronavirus Disease 2019 (COVID-19) Pandemic: Insights and Clinical Strategies From a Center at the Epicenter.

BACKGROUND: The onset of the coronavirus disease 2019 (COVID-19) pandemic has forced our cardiac surgery program 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 program, 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 programs around the world will eventually face COVID-19 with varying levels of infection burden and different resources, and we hope this document can assist programs to plan for the future.

Extracorporeal membrane oxygenation for primary graft dysfunction after heart transplant.

OBJECTIVE: Venoarterial extracorporeal membrane oxygenation is a useful treatment for severe primary graft dysfunction after heart transplant. The ideal timing of initiation is unknown. METHODS: 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. RESULTS: 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). CONCLUSIONS: 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.