Spinal cord protection for thoracoabdominal aortic aneurysm repair: from bench to bedside.

This keynote lecture and corresponding presentation discuss the anatomy and pathophysiology surrounding spinal cord injury in aortic surgery. This article will discuss risk factors and mechanisms for spinal cord injury, including loss of direct and collateral spinal cord perfusion and ischemia-reperfusion injury. This review will examine these elements in both the laboratory and clinical setting, in addition to other neuroprotective strategies applied in clinical practice.

Mirizzi syndrome complicated by type IV cholecystobiliary fistula to the right hepatic duct.

Mirizzi syndrome is a rare complication of long-term chronic cholecystitis, characterized by extrinsic compression of the common hepatic duct that may progress to development of cholecystobiliary fistula. Here we report a case of a 38-year-old female patient who underwent laparoscopic cholecystectomy with intraoperative cholangiogram for acute cholecystitis and choledocholithiasis. Intraoperatively, the patient was found to have a Mirizzi syndrome complicated by cholecystobiliary fistula to the right hepatic duct.

Challenging Paradigm Limits of Retrograde Cerebral Perfusion During Lower Body Circulatory Arrest.

Introduction: Retrograde cerebral perfusion (RCP) is a safe and effective technique to augment cerebral protection during lower body circulatory arrest in patients undergoing elective hemiarch replacement. However, recommendations guiding optimal temperature, flow rate, and perfusion pressure are outdated and potentially overly limiting. We report our experience using RCP for elective hemiarch replacement with parameters that challenge the currently accepted paradigm.

Evaluating the risk of spinal cord ischemia in zone 2 frozen elephant trunk replacement.

Background: The appropriate stent length in frozen elephant trunk replacements (FET) remains debated relative to the risk for paraplegia. However, landing the distal end of the stent beyond the curve of the arch facilitates distal reintervention, which is commonly beyond the 10 cm stent coverage when deployed proximal to the left subclavian artery. The aim of this study was to evaluate outcomes following the use of 15 cm stent grafts in zone 2 (z2, distal to the left common carotid).

Direct Innominate Artery Cannulation versus Side Graft for Selective Antegrade Cerebral Perfusion during Aortic Hemiarch Replacement.

Background:  Selective antegrade cerebral perfusion (SACP) has become our preferred method for cerebral protection during open arch cases. While the initial approach involved sewing a graft to the innominate artery as the arterial cannulation site, our access strategy has since evolved to central aortic cannulation with use of a percutaneous cannula in the innominate for SACP. We hypothesized that SACP delivered via direct innominate cannulation using a 12- or 14-Fr cannula results in equivalent outcomes to cases utilizing a side graft.

Direct and indirect activation of the adenosine triphosphate-sensitive potassium channel to induce spinal cord ischemic metabolic tolerance.

Objectives: The mitochondrial adenosine triphosphate-sensitive potassium channel is central to pharmacologically induced tolerance to spinal cord injury. We hypothesized that both direct and nitric oxide-dependent indirect activation of the adenosine triphosphate-sensitive potassium channel contribute to the induction of ischemic metabolic tolerance.

Methods: Spinal cord injury was induced in adult male C57BL/6 mice through 7 minutes of thoracic aortic crossclamping.

Reactive Oxygen Species Mediate Nicorandil-induced Metabolic Tolerance to Spinal Cord Injury.

Background: Spinal cord injury remains a devastating complication of thoracoabdominal aortic surgery. We previously demonstrated that pretreatment with nicorandil preserved motor function in a murine spinal cord injury model through mitochondrial adenosine triphosphate-sensitive potassium channel activation. We hypothesized that the neuroprotective effect of nicorandil is mediated by downstream generation of reactive oxygen species.

Optimizing Nicorandil for Spinal Cord Protection in a Murine Model of Complex Aortic Intervention.

There are currently no clinically utilized pharmacological agents for the induction of metabolic tolerance to spinal cord ischemia-reperfusion injury in the setting of complex aortic intervention. Nicorandil, a nitric oxide donor and ATP-sensitive potassium (KATP) channel opener, has shown promise in neuroprotection. However, the optimized clinical application of the drug and its mechanism of neuroprotection remains unclear.

Right Thoracoscopic Aberrant Right Subclavian Artery Division and Subclavian-Carotid Transposition.

Video-assisted thoracoscopic surgical division of obstructive congenital vascular rings has been demonstrated to be a safe technique in the setting of right-sided or double aortic arch, requiring a left-sided thoracic approach. This report describes 2 cases of aberrant right subclavian artery division using right video-assisted thoracoscopic surgery and subclavian-carotid transposition. This approach is safe and feasible in the management of symptomatic aberrant right subclavian artery without the morbidity of a thoracotomy incision, although patients require ongoing surveillance.

Noteworthy Cardiac Literature 2019: Cerebral Protection, Zone 2 Arch, Intravascular Ultrasonography in Dissection, Heart Allocation, and Mitral Durability.

The year of 2019 continues to have notable literature advancing the practice of cardiac surgery. In this article, topics of discussion will include the evolution of cerebral protection, the advancement of arch surgical techniques, the heart transplant allocation system, and mitral repair approach and durability.

Utility of neuromonitoring in hypothermic circulatory arrest cases for early detection of stroke: Listening through the noise.

Objective: Stroke remains a potentially devastating complication of aortic arch intervention. The value of neurophysiologic intraoperative monitoring (NIOM) in the early identification of stroke is unclear. We evaluated the utility of NIOM for early stroke detection in aortic arch surgery.

"Bedside Anatomy": A Tool to Contextualize Learning and Introduce Surgical Careers.

Background: Many medical students cite an unwelcoming culture in surgery and perceive surgeons as arrogant or unfriendly. These perceptions have been reported as factors discouraging medical students from applying to surgical residency programs. This highlights an opportunity early in medical education to address these negative stereotypes and create opportunities for positive interactions with surgeons.

Predictors of Acute Kidney Injury Following Aortic Arch Surgery.

Background: Acute kidney injury (AKI) following open aortic arch surgery is a frequent complication associated with increased morbidity and mortality. The primary purpose of this study was to evaluate risk factors for postoperative AKI in patients who underwent open aortic arch surgery utilizing hypothermic circulatory arrest (HCA).

Materials And Methods: Included were 295 patients undergoing surgery between January 2011 and March 2018.

Spinal Cord Protection for Thoracic Aortic Surgery: Bench to Bedside.

This article summarizes the anatomically driven pathophysiology of spinal cord injury, the impact of ischemia reperfusion on the cellular level, current research in developing neuronal ischemic tolerance, and promotion of collateralization. It addresses neuroprotective strategies in modern clinical practice, current pharmacologic interventions, and continued challenges in the management of complex aortic disease. The pathophysiology of spinal cord injury includes disruption and recovery of collateral blood flow and the effects of malperfusion on the spinal cord.

Innominate Versus Axillary Artery Cannulation for the Hemiarch Repair.

Background: Innominate artery cannulation has gained some popularity over the last decade as an alternative to axillary artery cannulation for providing selective antegrade cerebral perfusion during repair of the ascending aorta and arch. Innominate artery cannulation provides several advantages including avoidance of an additional incision and use of a larger caliber artery to provide less resistance to high flow during bypass and selective antegrade cerebral perfusion. We hypothesize that these advantages make innominate artery cannulation superior to axillary artery cannulation as it can decrease operative times and potentially decrease blood loss.

Interleukin-19 is cardioprotective in dominant negative cyclic adenosine monophosphate response-element binding protein-mediated heart failure in a sex-specific manner.

Aim: To investigate the role of interleukin-19 (IL-19) in a murine model of female-dominant heart failure (HF).

Methods: Expression of one copy of a phosphorylation-deficient cyclic adenosine monophosphate response-element binding protein (dnCREB) causes HF, with accelerated morbidity and mortality in female mice compared to males. We assessed expression of IL-19, its receptor isoforms IL-20R α/β, and downstream IL-19 signaling in this model of female-dominant HF.