Differences in Brain Metabolite Profiles Between Normothermia and Hypothermia.

BACKGROUND: This study evaluated the difference in brain metabolite profiles between normothermia and hypothermia reaching 25°C in humans in vivo. METHODS: Thirteen patients who underwent thoracic aorta surgery under moderate hypothermia were prospectively enrolled. Plasma samples were collected simultaneously from the arteries and veins to estimate metabolite uptake or release. Targeted metabolomics based on liquid chromatographic mass spectrometry and direct flow injection were performed, and changes in the profiles of respective metabolites from normothermia to hypothermia were compared. The ratios of metabolite concentrations in venous blood samples to those in arterial blood samples (V/A ratios) were calculated, and log2 transformation of the ratios [log2(V/A)] was performed for comparison between the temperature groups. RESULTS: Targeted metabolomics were performed for 140 metabolites, including 20 amino acids, 13 biogenic amines, 10 acylcarnitines, 82 glycerophospholipids, 14 sphingomyelins, and 1 hexose. Of the 140 metabolites analyzed, 137 metabolites were released from the brain in normothermia, and the release of 132 of these 137 metabolites was decreased in hypothermia. Two metabolites (dopamine and hexose) showed constant release from the brain in hypothermia, and 3 metabolites (2 glycophospholipids and 1 sphingomyelin) showed conversion from release to uptake in hypothermia. Glutamic acid demonstrated a distinct brain metabolism in that it was taken up by the brain in normothermia, and the uptake was increased in hypothermia. CONCLUSION: Targeted metabolomics demonstrated various degrees of changes in the release of metabolites by the hypothermic brain. The release of most metabolites was decreased in hypothermia, whereas glutamic acid showed a distinct brain metabolism.

Spinal Cord Protection for Thoracoabdominal Aortic Surgery.

Open and endovascular repairs of the descending thoracic and thoracoabdominal aorta are associated with a substantial risk of spinal cord injury, namely paraplegia. Endovascular repairs seem to have a lower incidence of spinal cord injury, but there have been no randomized trials comparing outcomes of open and endovascular repairs. Paraplegia occurs when collateral blood supply to the anterior spinal artery is impaired. The risk of spinal cord injury can be mitigated with perioperative protocols that include drainage of cerebrospinal fluid, avoidance of hypotension and anemia, intraoperative neurophysiologic monitoring, and advanced surgical techniques. Drainage of cerebrospinal fluid using a spinal drain decreases the risk of spinal cord ischemia by improving spinal cord perfusion pressure. However, cerebrospinal fluid drainage has risks including neuraxial and intracranial bleeding, and these risks need to be carefully weighed against its potential benefit. This review discusses current surgical management of descending thoracic and thoracoabdominal aortic disease, incidence of and risk factors for spinal cord injury, and elements of spinal cord protection protocols that pertain to anesthesiologists, with a focus on cerebrospinal fluid drainage.

Post-operative computed tomography imaging evaluation of ascending aorta surgery.

Ascending thoracic aorta disease is often a life-threatening condition. Aortic aneurysm and aortic dissection are the most frequent ascending aorta diseases requiring surgical intervention. Surgical repair techniques of the ascending aorta are various; they include reconstruction of the ascending aorta by using a graft with or without a prosthetic valve, reconstruction with a composite artificial graft or using a biological graft, and reconstruction of the ascending aorta with a composite graft preserving the native valve and arch repair. The radiologist plays a key role in the identification of post-operative complications; differentiation from normal postoperative findings is fundamental. Our aim is to discuss the main diseases affecting the ascending aorta requiring surgery and the different techniques used to treat them. We also discuss the normal computed tomography (CT) imaging findings and after-surgery complications.

Unexpected thrombus migration obstructing the right coronary ostium after thoracic aorta graft replacement.

Unexpected and reversible causes of ventricular dysfunction requiring a prompt second surgical procedure to restore the cardiac function should always be sought before the initiation of positive inotropic support. We report a case of obstruction of the right coronary ostium by an organized thrombus that had migrated retrogradely from the false lumen of a dissected aortic aneurysm. The resultant ventricular dysfunction hindered separation from cardiopulmonary bypass. Prompt recognition was done by transesophageal echocardiography and a second surgical procedure was immediately performed to remove the thrombus before irreversible ventricular dysfunction occurred.

Extensive Type A Aortic Arterial Dissection Presenting With Stroke Symptoms: A Case Report.

Aortic dissection (AD) is a rare but often lethal condition if not properly and urgently treated. Most often, patients arrive with acute hemodynamic instability and ripping chest agony. The patient's life depends critically on a correct diagnosis made as soon as possible. We describe a 60-year-old man who arrived at the emergency room with symptoms of a brain stroke, including poor consciousness, left-sided weakness, and speech disturbance associated with hemodynamic instability, and chest pain. Thoracic aortic arch dissection was observed on CT angiography (CTA). In addition, CTA revealed that the dissection extends proximally into the left common carotid artery, left subclavian artery, brachiocephalic trunk, and right common carotid artery and distally to the left common iliac artery, coupled with significant stenosis of the left common iliac artery. Proper management of blood pressure (BP) parameters is life-saving for the patient. Since our hospital did not offer cardiothoracic surgery services, the patient was transferred to a different institution, where he received medical care immediately from an expert team and had surgery.

Optimisation of Volume Flow Rates when Using Endovascular Shunting Techniques: An Experimental Study in Different Bench Flow Circuits.

Objective: Acute tissue ischaemia may arise due to arterial emergencies or during more complex vascular procedures and may be mitigated by temporary shunting techniques.Endovascular shunting (ES) techniques enable percutaneous access and shunting from the donor artery without the need to completely interrupt the arterial flow in the donor artery. An endoshunt system may also cover longer distances than most conventional shunts. The aim was to investigate and optimise the flow rates in different endovascular shunt systems. Methods: Step 1: The flow capacity of different ES configurations was compared with the flow capacity of a 9 Fr Pruitt-Inahara shunt (PIS). An intravenous bag with 0.9% NaCl, pressurised to 90 mmHg, was connected simultaneously to a PIS and to one of the tested ES configurations. The two shunt systems were then opened at the same time.The delivered fluid volumes from the shunt systems were collected and measured. The volume flow rate was subsequently calculated.Steps 2 and 3: Within a heart lung machine circuit, pressure-flow charts were constructed for the individual ES components and for the fully connected optimised endoshunt systems. The flow rate was increased in steps of 40-50 mL/min while monitoring the driving pressure, enabling the creation and comparison of the pressure-flow charts for the individually tested components. In total, seven individual inflow and outflow potential ES components were investigated with inflow and outflow diameters ranging from 6 to 15 Fr. Results: ES systems based on standard donor introducers led to substantially lower volume flow than the corresponding PIS volume flow, whereas ES systems based on dedicated 6 or 8 Fr dialysis access introducers (Prelude Short Sheet, Merit Medical) matched PIS flow rates. The introduction of 30 cm long »'' perfusion tubing within the ES system did not affect volume flow for any of the tested ES configurations. Conclusion: Endoshunting techniques can match PIS volume flow rates over short and long distances. The achieved ES flow rate is highly dependent on the components used within the ES system.

Corrigendum to "Optimization of Volume Flow Rates when Using Endovascular Shunting Techniques - An Experimental Study in Different Bench Flow Circuits. [EJVES Vascular Forum Volume 58, 2023, Pages 5-10]".

[This corrects the article DOI: 10.1016/j.ejvsvf.2022.11.002.][This corrects the article DOI: 10.1016/j.ejvsvf.2023.03.001.].

Does Intraoperative Fibrinogen Affect Blood Loss or Transfusion Practice After Aortic Arch Surgery: A Prematurely Ended Randomized Trial.

Cardiovascular surgery is often complicated by significant bleeding due to perioperative coagulopathy. The effectiveness of treatment with fibrinogen concentrate to reduce the perioperative blood transfusion rate after thoracic aortic replacement surgery in prior studies has shown conflicting results. Therefore, we conducted a double-blind randomized controlled trial to investigate if a single dose of intraoperative fibrinogen administration reduced blood loss and allogeneic transfusion rate after elective surgery for thoracic arch aneurysm with deep hypothermic circulatory arrest. Twenty patients were randomized to fibrinogen concentrate (N = 10) or placebo (N = 10). The recruitment of study patients was prematurely ended due to a low inclusion rate. Perioperative transfusion, 5-minute bleeding mass after study medication and postoperative blood loss were not different between the groups with fibrinogen concentrate or placebo. Due to small volumes of postoperative blood loss and premature study termination, a beneficial effect of fibrinogen concentrate on the number of blood transfusions could not be established. However, treatment with fibrinogen efficiently restored fibrinogen levels and clot strength to preoperative values with a more effective preserved postoperative thrombin generation capacity. This result might serve as a pilot for further multicenter studies to assess the prospective significance of automated and standardized thrombin generation as a routine assay for monitoring perioperative coagulopathy and its impact on short- and long-term operative results.

Risk factors and complications associated with intra-operative or post-operative identification of a PFO in cardiac surgery patients: A cohort study.

Introduction: It is unknown whether patent foramen ovale (PFO) reopening in the peri-operative setting of cardiac surgery affects the risk for stroke and post-operative outcomes. Methods: We performed a single-center, retrospective study based on a prospectively collected database in a tertiary cardiac surgery center. Using logistic regression, we assessed risk factors of PFO finding around surgery and subsequent clinical complications. Results: Between January 2007 and July 2019, 11034 patients who underwent cardiac surgery in our center were included. A total of 233 patients (2.1%) presented a finding of PFO including 138 per-operative disclosures and 95 post-operative finding for hypoxemia. In the whole cohort, the mean age was 68.4 ± 11.5 years including 73.9% of men. Post-operative PFO finding was associated with more ischemic strokes compared with per-operative finding and control group [7(7.4%) vs. 3(2.2%) vs. 236(2.2), respectively; p = 0.003]. Moreover, patients with post-operative PFO reopening experienced a higher rate of pneumonia, reintubation, and longer length of stay in the ICU. Post-operative reopening of PFO, but not per-operative finding, was independently associated with ischemic strokes {adjusted odds-ratio = 3.5, 95% confidence interval (CI) [1.6-7.8]; p = 0.002}. Other variables associated with stroke incidence included age, mitral valve surgery, and ascending aorta surgery. Per- or post-operative PFO closure was associated with reduced adverse respiratory outcomes and a trend of the lower cerebral ischemic event. Conclusion: Patent foramen ovale finding incidence in peri-operative cardiac surgery care was rare (2%) but post-operative finding of PFO was associated with a increased risk of ischemic strokes, worsened respiratory outcomes, and prolonged hospitalization.

Transthoracic aorto-axillary extra-anatomical bypass for difficult subclavian artery revascularization: a multicenter patency study.

In situ revascularization of the subclavian artery can be challenging in the context of emergency situations, a large aortic aneurysm with a posteriorly displaced left subclavian artery, a complex redo procedure or in the presence of an aberrant subclavian artery. A transthoracic aorto-axillary extra-anatomical bypass is a low risk alternative to in situ revascularization or carotid to subclavian bypass. We herein describe the surgical steps during a single-stage surgery complex aortic arch surgery. We report a 95.3% graft patency for 77 consecutive transthoracic aorto-axillary extra-anatomical bypass performed to 66 patients at the mean follow-up of 2.9 ± 2.4 years. We encountered 3 early (before 180 days postop) graft failures and no late graft failure. Graft failure had no clinical significance.

When echocardiography fails, intravascular ultrasound as an alternative for adequate graft patency in hybrid elephant trunk surgery.

Aortic pathology is a common cardiovascular disease in the US. Transesophageal Echocardiogram is an invaluable imaging modality in the management of aortic pathology in perioperative setting. Intravascular ultrasound can assess coronary obstruction during coronary interventions and can be used in endovascular aneurysm repair. A 54-year-old male underwent Hybrid Elephant Trunk Surgery, for complex open aorta repair. There was functional confirmation graft patency via the femoral arterial line tracing, there was surgical confirmation via visual and physical inspection of graft, but there was lacking anatomical confirmation. Epiaortic ultrasound reassured the graft patency at level of the arch. However, transesophageal echocardiogram was not reassuring for adequate anatomical confirmation of patency. Intravascular ultrasound was used for anatomical confirmation of graft patency and position. This technology provides real time graft patency and is a great tool in open aorta reconstruction surgery.

RETRACTED: Anesthesic and surgical guideline for the treatment of the thoraco-abdominal aorta. Consensus Document of the Spanish Societies of Anesthesia and Cardiovascular Surgery. / Guía anestésico-quirúrgica en el tratamiento de la patología de aorta toracoabdominal. Documento de Consenso de la Sociedad Española de Cirugía Cardiovascular Endovascular y la Sociedad Española de Anestesiología, Reanimación y Terapeútica del Dolor.

Este artículo ha sido retirado por indicación del Editor Jefe de la revista, después de constatar que parte de su contenido había sido plagiado, sin mencionar la fuente original: European Heart Journal (2014) 35, 2873 926.: https://academic.oup.com/eurheartj/article/35/41/2873/407693#89325738 El autor de correspondencia ha sido informado de la decisión y está de acuerdo con la retirada del artículo. El Comité Editorial lamenta las molestias que esta decisión pueda ocasionar. Puede consultar la política de Elsevier sobre la retirada de artículos en https://www.elsevier.com/about/our-business/policies/article-withdrawal

Advanced three-dimensionally engineered simulation model for aortic valve and proximal aorta procedures.

OBJECTIVES: A 3-dimensionally (3D) engineered model for simulation of aortic valve and proximal aortic procedures is a reliable tool both for training young surgeons and for simulating complex cases. To achieve a realistic simulation, the artificial model should reproduce the angles and orientations of the cardiac structures based on the patient's anatomical condition, reproduce tissue mechanical characteristics and be easy to obtain and easy to use. The goal of the study was the production and validation of realistic training models, based on the patient's actual anatomical characteristics, to provide training for aortic valve procedures. METHODS: An anatomical model was manufactured using 3D printing and silicone casting. The digital anatomical model was obtained by segmenting computed tomography imaging. The segmented geometrical images were processed and a casting mould was designed. The mould was manufactured on a 3D printer. Silicone was cast into the mould; after curing, the finished model was ready. The realistic reproduction was evaluated by mechanical hardness tests and a survey by cardiac surgeons. RESULTS: Six 3D silicone models were produced that represented the patient's anatomy including aortic valve leaflets, aortic root with coronary ostia, ascending aorta and proximal arch. Aortic valve replacement was performed, and 100% of the participants evaluated the model in a survey as perfectly reproducing anatomy and surgical handling. CONCLUSIONS: We produced a realistic, cost-effective simulator for training purposes and for simulation of complex surgical cases. The model reproduced the real angulation and orientation of the aortic structures inside the mediastinum, permitting a real-life simulation of the desired procedure. This model offers opportunities to simulate various surgical procedures.

Graft Perforation by a Spinal Bony Spur: An Unusual Cause of Late Bleeding after Thoracoabdominal Aorta Replacement.

We report an unusual case of delayed bleeding after open surgical repair of a thoracoabdominal aortic aneurysm. A 79-year-old man developed a massive retroperitoneal hematoma 49 days after Crawford type III thoracoabdominal aorta replacement. During emergency surgery, a tear was found in the prosthetic vascular graft caused by a sharp bony spur arising from the second lumbar vertebral body. This rare, but potentially lethal, complication indicates that attention should be paid to sharp bony structures during open repair of the descending aorta.

Loeys-Dietz syndrome: Intermediate-term outcomes of medically and surgically managed patients.

OBJECTIVES: Loeys-Dietz syndrome (LDS) is an aggressive connective tissue disorder associated with increased risk of aortic dissection and aneurysm rupture at an early age and smaller aortic diameters. We report our experience with LDS to better understand its natural history and treatment outcomes and help establish treatment guidelines. METHODS: We retrospectively reviewed all patients with LDS who underwent medical or surgical treatment at Cleveland Clinic before April 27, 2017. Primary endpoints were postoperative in-hospital morbidity and mortality. Secondary endpoints were aorta-related reoperations and short- and long-term mortality. RESULTS: We identified 53 patients with LDS. Of these, 33 (62%) underwent aortic surgery. Mean age was 39 ± 14 years, and mean maximum aortic diameter was 4.3 cm. There were 2 (6%) deaths after urgent or emergency surgery. Twenty-two patients (67%) required no aortic reoperation; 20 of these had prophylactic surgery. Multiple aortic operations were performed on 11 (33%) patients, 9 of whom experienced aortic dissections. Six patients (18%) required total aortic replacement. Among 19 patients with modified root reimplantation, no aorta- or valve-related complications occurred. Overall, 33 patients underwent 58 aortic and 81 cardiovascular operations, with 1 late death. Kaplan-Meier survival of the aortic-surgery cohort was 89% at 10 years (median follow-up 5.2 years). There were no late deaths in the non-aortic surgery group (20/53; 38%). CONCLUSIONS: Prophylactic aortic surgical outcomes in LDS are excellent. Surgical reintervention remains high, particularly after aortic dissections. Close surveillance of medically managed and postoperative patients and early prophylactic surgery are crucial to avoid aortic catastrophe and achieve a good long-term prognosis.

Aortic translocation with autologous tissue.

Aortic translocation, although technically demanding, could be an excellent surgical option for d-transposition of the great vessels and left ventricular outflow tract obstruction. We report a modification of the aortic translocation technique that uses autologous tissue. The aortic root is mobilized from the right ventricle with an extension of infundibular free-wall muscle for use in closure of the ventricular septal defect, which is similar to the technique for harvesting pulmonary autograft in the Ross-Konno procedure. Our modification may offer an even better surgical outcome for aortic translocation.

A Comparative Study of Abdominal Aortic Aneurysm: Endovascular Aneurysm Repair versus Open Repair.

BACKGROUND: Endovascular aneurysm repair (EVAR) has dramatically changed the management of abdominal aortic aneurysms (AAAs) as the number of open aneurysm repairs have declined over time. This report compares AAA-related demographics, operative data, complications, and mortality after treatment by open aneurysm repair or EVAR. METHODS: We retrospectively reviewed 136 patients with AAAs who were treated over an 8-year time period with open aneurysm repair or EVAR. RESULTS: The mean age of the EVAR group was higher than that of the open repair group (p=0.001), and hospital mortality did not differ significantly between groups (p=0.360). However, overall survival was significantly lower in the EVAR group (p=0.033). CONCLUSION: Although EVAR is the primary treatment modality for elderly patients, it would be ideal to set slightly more stringent criteria within the anatomical guidelines contained in the instructions for use of the EVAR device when treating younger patients.

Outcomes of Open Repair of Mycotic Aortic Aneurysms with In Situ Replacement.

BACKGROUND: Mycotic aortic aneurysms are rare and life-threatening. Unfortunately, no established guidelines exist for the treatment of patients with mycotic aortic aneurysms. The purpose of this study was to evaluate the midterm outcomes of the open repair of mycotic thoracic and thoracoabdominal aneurysms and suggest a therapeutic strategy. METHODS: From 2006 to 2016, 19 patients underwent open repair for an aortic aneurysm. All infected tissue was extensively debrided and covered with soft tissue. We recorded the clinical findings, anatomic location of the aneurysm, bacteriology results, antibiotic therapy, morbidity, and mortality for these cases. RESULTS: The median age was 62±7.2 years (range, 16 to 78 years), 13 patients (68%) were men, and the mean aneurysm size was 44.5±4.9 mm. The mean time from onset of illness to surgery was 14.5±2.4 days. Aortic continuity was restored in situ with a Dacron prosthesis (79%), homograft (16%), or Gore-Tex graft (5%). Soft-tissue coverage of the prosthesis was performed in 8 patients. The mean follow-up time was 43.2±11.7 months. The early mortality rate was 10.5%, and the 5-year survival rate was 74.9%±11.5%. CONCLUSION: This study showed acceptable early and midterm outcomes of open repair of mycotic aneurysms. We emphasize that aggressive intraoperative debridement with soft-tissue coverage results in a high rate of success in these high-risk patients.

An Automated, Gravity-driven CSF Drainage System Decreases Complications and Lowers Costs.

BACKGROUND: FlowSafeTM (BeckerSmith Medical, Irvine, CA, USA) is a novel, robotic, external lumbar drainage (ELD) system, which was designed to control cerebrospinal fluid (CSF) drainage, reduce complications, and decrease treatment costs. METHODS:  Forty-seven consecutive neurosurgical patients requiring ELD were treated using the FlowSafe system. RESULTS: In 39 of 40 patients with traumatic and surgical dural openings, potential CSF leaks were avoided. In seven patients with suspected normal pressure hydrocephalus, post-infectious ventriculomegaly, or pseudotumor cerebrum, we were able to assess the likelihood of improvement with shunting. The system, therefore, produced what we considered to be the "desired result" in 46 of 47 patients (98%). Our one treatment failure (2%) involved a patient with unrecognized hydrocephalus who, following a Chiari repair with a dural patch graft, was drained for six days. A persistent CSF leak eventually required a reoperation. Two patients (4%) described low-pressure headaches during treatment. Both responded to temporarily suspending or reducing the drainage rate. We saw no complications. Required nursing interventions were minimal.  Conclusions: The FlowSafe system was safe and effective. In our experience, there were fewer complications compared to currently available ELD systems. The FlowSafe was well tolerated by our patients. The near elimination of nursing interventions should allow lumbar drainage to be delivered in less costly, non-intensive care unit settings. Larger trials will be needed.

Successful Repair of Type I Endoleak Using the Frozen Elephant Trunk Technique.

Thoracic endovascular aortic repair (TEVAR) has emerged as an effective therapy for a variety of thoracic aortic pathologies. However, various types of endoleak remain a major concern, and its treatment is often challenging. We report a case of type I endoleak occurring 19 months after zone II hybrid TEVAR. The endoleak was successfully repaired by the frozen elephant trunk technique, without removal of a previous stent graft, combined with ascending aorta and total arch replacement.