Effects of intravenous inflammasome inhibitor (NuSepin) on suppression of proinflammatory cytokines release induced by cardiopulmonary bypass in swine model: a pilot study.

The systemic inflammatory response syndrome can occur due to an inflammatory reaction to the release of cytokines, and it has been linked to the circulation of pro- and anti-inflammatory cytokines. The cardiopulmonary bypass (CPB) system is known to activate numerous inflammatory pathways. Applying CPB in large animals for an extended period may be useful as a controlled experimental model for systemic inflammatory responses. The authors hypothesized that 0.2 mg/kg NuSepin® would inhibit CBP-induced proinflammatory cytokine release, and attenuate CPB-induced vasoplegia. CPB was maintained for 2 h in 8 male Yorkshire pigs. Ten ml of saline was administered intravenously to the control group, while the study group received 10 ml of NuSepin® (0.2 mg/kg), before start of CPB. Blood samples were collected at four different time points to evaluating the level of cytokine (TNF-α, IL-1ß, IL-6, IL-8) release during and after CBP. All vital signals were recorded as continuous waveforms using the vital recorder®. Our study demonstrated that IL-6 increased in both groups during CPB remained unchanged. However, in the Nusepin group, IL-6 levels rapidly decreased when CPB was stopped and the proinflammatory reaction subsided. Furthermore, the dose of norepinephrine required to maintain a mean pressure of 60 mmHg was also lower in the Nusepin group.

Features and Outcomes of Females and Males Requiring Postcardiotomy Extracorporeal Life Support.

BACKGROUND: Although cardiogenic shock requiring extracorporeal life support (ECLS) after cardiac surgery is associated with high mortality, the impact of sex on outcomes of post-cardiotomy ECLS remains unclear with conflicting results in literature. We compare patient characteristics, in-hospital outcomes, and overall survival between females and males requiring post-cardiotomy ECLS. METHODS: This retrospective, multicentre (34 centres), observational study included adults requiring post-cardiotomy ECLS between 2000 and 2020. Pre-operative, procedural, and ECLS characteristics, complications, and survival were compared between females and males. Association between sex and in-hospital survival was investigated through mixed-Cox proportional hazards models. RESULTS: This analysis included 1823 patients [females:40.8%; median age:66.0 (interquartile range:56.2-73.0 years)]. Females underwent more mitral (females:38.4%, males:33.1%, p=0.019) and tricuspid (females:18%, males:12.4%, p<0.001) valve surgery, while males had more coronary artery surgery (females:45.9%, males:52.4%, p=0.007). ECLS implantation was more common intra-operatively in females (females:64.1%, males:59.1%) and post-operatively in males (females:35.9%, males:40.9%, p=0.036). Ventricular unloading (females:25.1%, males:36.2%, p<0.001) and intra-aortic balloon pump (females: 25.8%, males:36.8%, p<0.001) were most frequently used in males. Females suffered more post-operative right ventricular failure (females:24.1%, males:19.1%, p=0.016) and limb ischemia (females:12.3%, males:8.8%, p=0.23). In-hospital mortality was 64.9% in females and 61.9% in males (p=0.199) with no differences in 5-year survival (females:20%, 95%CI:17-23; males:24%, 95%CI:21-28;p=0.069). Crude hazard ratio for in-hospital mortality in females was 1.12 (95%CI: 0.99-1.27,p=0.069) and did not change after adjustments. CONCLUSIONS: This study demonstrates that females and males requiring post-cardiotomy ECLS have different pre-operative and ECLS characteristics, as well as complications, without a statistical difference in in-hospital and 5-year survival.

Improvement of Transfusion Practice in Cardiothoracic Surgery Through Implementing a Patient Blood Management Program.

Background: In this study, we examined the impact of a patient blood management (PBM) program on red blood cell (RBC) transfusion practices in cardiothoracic surgery. Methods: The PBM program had 3 components: monitoring transfusions through an order communication system checklist, educating the medical team about PBM, and providing feedback to ordering physicians on the appropriateness of transfusion. The retrospective analysis examined changes in the hemoglobin levels triggering transfusion and the proportions of appropriate RBC transfusions before, during, and after PBM implementation. Further analysis was focused on patients undergoing cardiac surgery, with outcomes including 30-day mortality, durations of intensive care unit and hospital stays, and rates of pneumonia, sepsis, and wound complications. Results: The study included 2,802 patients admitted for cardiothoracic surgery. After the implementation of PBM, a significant decrease was observed in the hemoglobin threshold for RBC transfusion. This threshold dropped from 8.7 g/dL before PBM to 8.3 g/dL during the PBM education phase and 8.0 g/dL during the PBM feedback period. Additionally, the proportion of appropriate RBC transfusions increased markedly, from 23.9% before PBM to 34.9% and 58.2% during the education and feedback phases, respectively. Among the 381 patients who underwent cardiac surgery, a significant reduction was noted in the length of hospitalization over time (p<0.001). However, other clinical outcomes displayed no significant differences. Conclusion: PBM implementation effectively reduced the hemoglobin threshold for RBC transfusion and increased the rate of appropriate transfusion in cardiothoracic surgery. Although transfusion practices improved, clinical outcomes were comparable to those observed before PBM implementation.

Fulminant myocarditis proven by early biopsy and outcomes.

BACKGROUND AND AIMS: While endomyocardial biopsy (EMB) is recommended in adult patients with fulminant myocarditis, the clinical impact of its timing is still unclear. METHODS: Data were collected from 419 adult patients with clinically suspected fulminant myocarditis admitted to intensive care units across 36 tertiary centres in 15 countries worldwide. The diagnosis of myocarditis was histologically proven in 210 (50%) patients, either by EMB (n = 183, 44%) or by autopsy/explanted heart examination (n = 27, 6%), and clinically suspected cardiac magnetic resonance imaging confirmed in 96 (23%) patients. The primary outcome of survival free of heart transplantation (HTx) or left ventricular assist device (LVAD) at 1 year was specifically compared between patients with early EMB (within 2 days after intensive care unit admission, n = 103) and delayed EMB (n = 80). A propensity score-weighted analysis was done to control for confounders. RESULTS: Median age on admission was 40 (29-52) years, and 322 (77%) patients received temporary mechanical circulatory support. A total of 273 (65%) patients survived without HTx/LVAD. The primary outcome was significantly different between patients with early and delayed EMB (70% vs. 49%, P = .004). After propensity score weighting, the early EMB group still significantly differed from the delayed EMB group in terms of survival free of HTx/LVAD (63% vs. 40%, P = .021). Moreover, early EMB was independently associated with a lower rate of death or HTx/LVAD at 1 year (odds ratio of 0.44; 95% confidence interval: 0.22-0.86; P = .016). CONCLUSIONS: Endomyocardial biopsy should be broadly and promptly used in patients admitted to the intensive care unit for clinically suspected fulminant myocarditis.

Patient and Management Variables Associated With Survival After Postcardiotomy Extracorporeal Membrane Oxygenation in Adults: The PELS-1 Multicenter Cohort Study.

Background Extracorporeal membrane oxygenation (ECMO) has been increasingly used for postcardiotomy cardiogenic shock, but without a concomitant reduction in observed in-hospital mortality. Long-term outcomes are unknown. This study describes patients' characteristics, in-hospital outcome, and 10-year survival after postcardiotomy ECMO. Variables associated with in-hospital and postdischarge mortality are investigated and reported. Methods and Results The retrospective international multicenter observational PELS-1 (Postcardiotomy Extracorporeal Life Support) study includes data on adults requiring ECMO for postcardiotomy cardiogenic shock between 2000 and 2020 from 34 centers. Variables associated with mortality were estimated preoperatively, intraoperatively, during ECMO, and after the occurrence of any complications, and then analyzed at different time points during a patient's clinical course, through mixed Cox proportional hazards models containing fixed and random effects. Follow-up was established by institutional chart review or contacting patients. This analysis included 2058 patients (59% were men; median [interquartile range] age, 65.0 [55.0-72.0] years). In-hospital mortality was 60.5%. Independent variables associated with in-hospital mortality were age (hazard ratio [HR], 1.02 [95% CI, 1.01-1.02]) and preoperative cardiac arrest (HR, 1.41 [95% CI, 1.15-1.73]). In the subgroup of hospital survivors, the overall 1-, 2-, 5-, and 10-year survival rates were 89.5% (95% CI, 87.0%-92.0%), 85.4% (95% CI, 82.5%-88.3%), 76.4% (95% CI, 72.5%-80.5%), and 65.9% (95% CI, 60.3%-72.0%), respectively. Variables associated with postdischarge mortality included older age, atrial fibrillation, emergency surgery, type of surgery, postoperative acute kidney injury, and postoperative septic shock. Conclusions In adults, in-hospital mortality after postcardiotomy ECMO remains high; however, two-thirds of those who are discharged from hospital survive up to 10 years. Patient selection, intraoperative decisions, and ECMO management remain key variables associated with survival in this cohort. Registration URL: https://www.clinicaltrials.gov; Unique identifier: NCT03857217.

On-Support and Postweaning Mortality in Postcardiotomy Extracorporeal Membrane Oxygenation.

BACKGROUND: Postcardiotomy venoarterial extracorporeal membrane oxygenation (VA ECMO) is characterized by discrepancies between weaning and survival-to-discharge rates. This study analyzes the differences between postcardiotomy VA ECMO patients who survived, died on ECMO, or died after ECMO weaning. Causes of death and variables associated with mortality at different time points are investigated. METHODS: The retrospective, multicenter, observational Postcardiotomy Extracorporeal Life Support Study (PELS) includes adults requiring postcardiotomy VA ECMO between 2000 and 2020. Variables associated with on-ECMO mortality and postweaning mortality were modeled using mixed Cox proportional hazards, including random effects for center and year. RESULTS: In 2058 patients (men, 59%; median age, 65 years; interquartile range [IQR], 55-72 years), weaning rate was 62.7%, and survival to discharge was 39.6%. Patients who died (n = 1244) included 754 on-ECMO deaths (36.6%; median support time, 79 hours; IQR, 24-192 hours), and 476 postweaning deaths (23.1%; median support time, 146 hours; IQR, 96-235.5 hours). Multiorgan (n = 431 of 1158 [37.2%]) and persistent heart failure (n = 423 of 1158 [36.5%]) were the main causes of death, followed by bleeding (n = 56 of 754 [7.4%]) for on-ECMO mortality and sepsis (n = 61 of 401 [15.4%]) for postweaning mortality. On-ECMO death was associated with emergency surgery, preoperative cardiac arrest, cardiogenic shock, right ventricular failure, cardiopulmonary bypass time, and ECMO implantation timing. Diabetes, postoperative bleeding, cardiac arrest, bowel ischemia, acute kidney injury, and septic shock were associated with postweaning mortality. CONCLUSIONS: A discrepancy exists between weaning and discharge rate in postcardiotomy ECMO. Deaths occurred during ECMO support in 36.6% of patients, mostly associated with unstable preoperative hemodynamics. Another 23.1% of patients died after weaning in association with severe complications. This underscores the importance of postweaning care for postcardiotomy VA ECMO patients.

Heterogeneity in Clinical Practices for Post-Cardiotomy Extracorporeal Life Support: a Pilot Survey from the PELS-1 Multicenter Study.

BACKGROUND: High-quality evidence for post-cardiotomy extracorporeal life support (PC-ECLS) management is lacking. This study investigated the real-world PC-ECLS clinical practices. METHODS: This cross-sectional, multi-institutional, international pilot survey explored center organization, anticoagulation management, left ventricular unloading, distal limb perfusion, PC-ECLS monitoring and transfusions practices. Twenty-nine questions were distributed among 34 hospitals participating in the Post-cardiotomy Extra-Corporeal Life Support Study. RESULTS: Of the 32 centers [16 low-volume (50%); 16 high-volume (50%)] that responded, 16 (50%) had dedicated ECLS specialists. Twenty-six centers (81.3%) reported using additional mechanical circulatory supports. Anticoagulation practices were highly heterogeneous: 24 hospitals (75%) reported using patient's bleeding status as a guide, without a specific threshold in 54.2% of cases. Transfusion targets ranged 7-10 g/dL. Most centers used cardiac venting on a case-by-case basis (78.1%) and regular distal limb perfusion (84.4%). Nineteen (54.9%) centers reported dedicated monitoring protocols including daily echocardiography (87.5%), Swan-Ganz catheterization (40.6%), cerebral near-infrared spectroscopy (53.1%) and multimodal assessment of limb ischemia. Inspection of the circuit (71.9%), oxygenator pressure drop (68.8%), plasma free hemoglobin (75%), d-dimer (59.4%), lactate dehydrogenase (56.3%) and fibrinogen (46.9%) are used to diagnose hemolysis and thrombosis. CONCLUSIONS: This study shows remarkable heterogeneity in clinical practices for PC-ECLS management. More standardized protocols and better implementation of available evidence are recommended.

The importance of timing in postcardiotomy venoarterial extracorporeal membrane oxygenation: A descriptive multicenter observational study.

OBJECTIVES: Postcardiotomy extracorporeal membrane oxygenation (ECMO) can be initiated intraoperatively or postoperatively based on indications, settings, patient profile, and conditions. The topic of implantation timing only recently gained attention from the clinical community. We compare patient characteristics as well as in-hospital and long-term survival between intraoperative and postoperative ECMO. METHODS: The retrospective, multicenter, observational Postcardiotomy Extracorporeal Life Support (PELS-1) study includes adults who required ECMO due to postcardiotomy shock between 2000 and 2020. We compared patients who received ECMO in the operating theater (intraoperative) with those in the intensive care unit (postoperative) on in-hospital and postdischarge outcomes. RESULTS: We studied 2003 patients (women: 41.1%; median age: 65 years; interquartile range [IQR], 55.0-72.0). Intraoperative ECMO patients (n = 1287) compared with postoperative ECMO patients (n = 716) had worse preoperative risk profiles. Cardiogenic shock (45.3%), right ventricular failure (15.9%), and cardiac arrest (14.3%) were the main indications for postoperative ECMO initiation, with cannulation occurring after (median) 1 day (IQR, 1-3 days). Compared with intraoperative application, patients who received postoperative ECMO showed more complications, cardiac reoperations (intraoperative: 19.7%; postoperative: 24.8%, P = .011), percutaneous coronary interventions (intraoperative: 1.8%; postoperative: 3.6%, P = .026), and had greater in-hospital mortality (intraoperative: 57.5%; postoperative: 64.5%, P = .002). Among hospital survivors, ECMO duration was shorter after intraoperative ECMO (median, 104; IQR, 67.8-164.2 hours) compared with postoperative ECMO (median, 139.7; IQR, 95.8-192 hours, P < .001), whereas postdischarge long-term survival was similar between the 2 groups (P = .86). CONCLUSIONS: Intraoperative and postoperative ECMO implantations are associated with different patient characteristics and outcomes, with greater complications and in-hospital mortality after postoperative ECMO. Strategies to identify the optimal location and timing of postcardiotomy ECMO in relation to specific patient characteristics are warranted to optimize in-hospital outcomes.

The Relation Between Obesity and Mortality in Postcardiotomy Venoarterial Membrane Oxygenation.

BACKGROUND: Obesity is an important health problem in cardiac surgery and among patients requiring postcardiotomy venoarterial extracorporeal membrane oxygenation (V-A ECMO). Still, whether these patients are at risk for unfavorable outcomes after postcardiotomy V-A ECMO remains unclear. The current study evaluated the association between body mass index (BMI) and in-hospital outcomes in this setting. METHODS: The Post-cardiotomy Extracorporeal Life Support (PELS-1) study is an international, multicenter study. Patients requiring postcardiotomy V-A ECMO in 36 centers from 16 countries between 2000 and 2020 were included. Patients were divided in 6 BMI categories (underweight, normal weight, overweight, class I, class II, and class III obesity) according to international recommendations. Primary outcome was in-hospital mortality, and secondary outcomes included major adverse events. Mixed logistic regression models were applied to evaluate associations between BMI and mortality. RESULTS: The study cohort included 2046 patients (median age, 65 years; 838 women [41.0%]). In-hospital mortality was 60.3%, without statistically significant differences among BMI classes for in-hospital mortality (P = .225) or major adverse events (P = .126). The crude association between BMI and in-hospital mortality was not statistically significant after adjustment for comorbidities and intraoperative variables (class I: odds ratio [OR], 1.21; 95% CI, 0.88-1.65; class II: OR, 1.45; 95% CI, 0.86-2.45; class III: OR, 1.43; 95% CI, 0.62-3.33), which was confirmed in multiple sensitivity analyses. CONCLUSIONS: BMI is not associated to in-hospital outcomes after adjustment for confounders in patients undergoing postcardiotomy V-A ECMO. Therefore, BMI itself should not be incorporated in the risk stratification for postcardiotomy V-A ECMO.

Perioperative Red Blood Cell Transfusion Is Associated With Adverse Cardiovascular Outcomes in Heart Valve Surgery.

BACKGROUND: We examined the relationship between blood transfusion and long-term adverse events to evaluate the clinical impact of red blood cell (RBC) transfusion on patients undergoing cardiac valve surgery. METHODS: From the National Health Insurance Service database, individuals undergoing heart valve surgery were verified, including aortic valve (AV), mitral valve (MV), tricuspid valve (TV), and complex valves (more than 2 valve surgeries). The interested outcomes were incidence of death, ischemic stroke, hemorrhagic stroke, and admission for myocardial infarction during follow-up. Associations between perioperative RBC transfusion and long-term cardiovascular events were analyzed with Cox-proportional hazard model. RESULTS: Perioperative RBC transfusion (±2 days from the day of surgery) was categorized into 0, 1, 2, and >3 units based on the number of packs transfused. From 2003 to 2019, the data of 58,299 individuals were retrieved (51.6% were male and 58% were aged above 60 years). The median follow-up duration was 5.53 years. Of the total cohort, 86.5% received at least 1 transfusion. In multivariable analysis, adverse cardiovascular event risk proportionally increased with transfusion in a dose-dependent manner. The adjusted hazard ratios and 95% confidence intervals of outcomes after the transfusion of 1, 2, and ≥3 units compared to those with no transfusion were as follows: death, 1.53 (1.41-1.66), 1.97 (1.81-2.14), and 3.03 (2.79-3.29); ischemic stroke, 1.27 (1.16-1.39), 1.31 (1.19-1.44), and 1.51 (1.38-1.66); hemorrhagic stroke, 1.38 (1.16-1.66), 1.71 (1.43-2.05), and 2.31 (1.94-2.76); and myocardial infarction 1.35 (1.13-1.62), 1.60 (1.33-1.91), and 1.99 (1.66-2.38), respectively (all P < .01). CONCLUSIONS: In the analysis of the national cohort, perioperative RBC transfusion during heart valve surgery was associated with adverse cardiovascular outcomes correlated with the volume of RBC transfusion.

Effect of a Patient Blood Management Program on the Appropriateness of Red Blood Cell Transfusion and Clinical Outcomes in Elderly Patients Undergoing Hip Fracture Surgery.

BACKGROUND: Elderly patients with hip fractures frequently receive perioperative transfusions, which are associated with increased morbidity and mortality. This study aimed to evaluate the impact of a patient blood management (PBM) program on the appropriateness of red blood cell (RBC) transfusion and clinical outcomes in geriatric patients undergoing hip fracture surgery. METHODS: In 2018, the revised PBM program was implemented at the Korea University Anam Hospital, Seoul, Republic of Korea. Elderly patients aged ≥ 65 years who underwent hip fracture surgery from 2017 to 2020 were evaluated. Clinical characteristics and outcomes were analyzed according to the timing of PBM implementation (pre-PBM, early-PBM, and late-PBM). Multiveriate regression analysis was used to evaluate the risk factors of the adverse outcomes, such as in-hospital mortality or 30-day readmission. RESULTS: A total of 884 elderly patients were included in this study. The proportion of patients who received perioperative RBC transfusions decreased significantly (43.5%, 40.1%, and 33.2% for pre-PBM, early-PBM, and late-PBM, respectively; P = 0.013). However, the appropriateness of RBC transfusion significantly increased (54.0%, 60.1%, and 94.7%, respectively; P < 0.001). The duration of in-hospital stay and 30-day readmission rates significantly decreased. Multivariable regression analysis revealed that RBC transfusion (odds ratio, 1.815; 95% confidence interval, 1.137-2.899; P = 0.013) was significantly associated with adverse outcomes. CONCLUSION: Implementing the PBM program increased the appropriateness of RBC transfusion without compromising transfusion quality and clinical outcomes. Therefore, adopting the PBM program may improve the clinical management of elderly patients following hip fracture surgery.

An innovative ovine model of severe cardiopulmonary failure supported by veno-arterial extracorporeal membrane oxygenation.

Refractory cardiogenic shock (CS) often requires veno-arterial extracorporeal membrane oxygenation (VA-ECMO) to sustain end-organ perfusion. Current animal models result in heterogenous cardiac injury and frequent episodes of refractory ventricular fibrillation. Thus, we aimed to develop an innovative, clinically relevant, and titratable model of severe cardiopulmonary failure. Six sheep (60 ± 6 kg) were anaesthetized and mechanically ventilated. VA-ECMO was commenced and CS was induced through intramyocardial injections of ethanol. Then, hypoxemic/hypercapnic pulmonary failure was achieved, through substantial decrease in ventilatory support. Echocardiography was used to compute left ventricular fractional area change (LVFAC) and cardiac Troponin I (cTnI) was quantified. After 5 h, the animals were euthanised and the heart was retrieved for histological evaluations. Ethanol (58 ± 23 mL) successfully induced CS in all animals. cTnI levels increased near 5000-fold. CS was confirmed by a drop in systolic blood pressure to 67 ± 14 mmHg, while lactate increased to 4.7 ± 0.9 mmol/L and LVFAC decreased to 16 ± 7%. Myocardial samples corroborated extensive cellular necrosis and inflammatory infiltrates. In conclusion, we present an innovative ovine model of severe cardiopulmonary failure in animals on VA-ECMO. This model could be essential to further characterize CS and develop future treatments.

Extracorporeal Membrane Oxygenation for Coronavirus Disease 2019: Expert Recommendations from The Korean Society for Thoracic and Cardiovascular Surgery.

Since the first reported case of coronavirus disease 2019 (COVID-19) in December 2019, the numbers of confirmed cases and deaths have continued to increase exponentially despite multi-factorial efforts. Although various attempts have been made to improve the level of evidence for extracorporeal membrane oxygenation (ECMO) treatment over the past 10 years, most experts still hesitate to take an active position on whether to apply ECMO in COVID-19 patients. Several ECMO management guidelines have been published recently, but they reflect some important differences from the Korean medical system and aspects of real-world medical practice in Korea. We aimed to find evidence on the efficacy of ECMO for COVID-19 patients by reviewing the published literature and to propose expert recommendations by analyzing the Korean COVID-19 ECMO registry data.

Association between Cumulative Fluid Balance and Outcomes in Acute Respiratory Distress Syndrome Patients Treated with Extracorporeal Membrane Oxygenation.

BACKGROUND: Extracorporeal membrane oxygenation (ECMO) has become increasingly accepted as a life-saving procedure for patients with severe acute respiratory distress syndrome (ARDS). This study investigated the relationship between cumulative fluid balance (CFB) and outcomes in adult ARDS patients treated with ECMO. METHODS: We retrospectively analyzed the data of adult ARDS patients who received ECMO between December 2009 and December 2019 at Korea University Anam Hospital. CFB was calculated during the first 7 days after ECMO initiation. The primary endpoint was 28-day mortality. RESULTS: The 74 patients were divided into survivor (n=33) and non-survivor (n=41) groups based on 28-day survival. Non-survivors showed a significantly higher CFB at 1-7 days (p<0.05). Cox multivariable proportional hazard regression revealed a relationship between CFB on day 3 and 28-day mortality (hazard ratio, 3.366; 95% confidence interval, 1.528-7.417; p=0.003). CONCLUSION: In adult ARDS patients treated with ECMO, a higher positive CFB on day 3 was associated with increased 28-day mortality. Based on our findings, we suggest a restrictive fluid strategy in ARDS patients treated with ECMO. CFB may be a useful predictor of survival in ARDS patients treated with ECMO.

Comparison of Hemodynamic Energy between Expanded Polytetrafluoroethylene and Dacron Artificial Vessels.

BACKGROUND: Artificial grafts such as polyethylene terephthalate (Dacron) and expanded polytetrafluoroethylene (ePTFE) are used for various cardiovascular surgical procedures. The compliance properties of prosthetic grafts could affect hemodynamic energy, which can be measured using the energy-equivalent pressure (EEP) and surplus hemodynamic energy (SHE). We investigated changes in the hemodynamic energy of prosthetic grafts. METHODS: In a simulation test, the changes in EEP for these grafts were estimated using COMSOL MULTIPHYSICS. The Young modulus, Poisson ratio, and density were used to analyze the grafts' material properties, and pre- and post-graft EEP values were obtained by computing the product of the pressure and velocity. In an in vivo study, Dacron and ePTFE grafts were anastomosed in an end-to-side fashion on the descending thoracic aorta of swine. The pulsatile pump flow was fixed at 2 L/min. Real-time flow and pressure were measured at the distal part of each graft, while clamping the other graft and the descending thoracic aorta. EEP and SHE were calculated and compared. RESULTS: In the simulation test, the mean arterial pressure decreased by 39% for all simulations. EEP decreased by 42% for both grafts, and by around 55% for the native blood vessels after grafting. The in vivo test showed no significant difference between both grafts in terms of EEP and SHE. CONCLUSION: The post-graft hemodynamic energy was not different between the Dacron and ePTFE grafts. Artificial grafts are less compliant than native blood vessels; however, they can deliver pulsatile blood flow and hemodynamic energy without any significant energy loss.

A Giant Pseudo-Aneurysm on the Anastomosis Site for a Redo Bentall Operation due to Behçet Disease Treated by Thoracic Endovascular Aortic Aneurysm Repair with a Custom-Made Stent Graft.

A 34-year-old man who had undergone aortic valve replacement 8 years ago underwent an additional Bentall operation due to mechanical valve dehiscence 2 years later. Subsequently, he was diagnosed with Behçet disease and Batter syndrome. A week after being hospitalized again due to chest pain and dyspnea, a large pseudo-aneurysm was detected on computed tomography. Because of the excessively large size of the pseudo-aneurysm, surgical treatment seemed very risky. Therefore, we planned to perform thoracic endovascular aortic repair (TEVAR) and treated him successfully. However, the patient experienced recurrence of the same symptoms 4 months later, and was found to have type IV endoleak. He received a TEVAR procedure again, and it was successful.

Management of Atrio-esophageal Fistula Induced by Radiofrequency Catheter Ablation in Atrial Fibrillation Patients: a Case Series.

Atrio-esophageal fistula (AEF) is one of the most devastating complication of radiofrequency catheter ablation (RFCA) of atrial fibrillation (AF) and surgical repair is strongly recommended. However, optimal surgical approach remains to be elucidated. We retrospectively reviewed AEF cases that occurred after RFCA in a single center and evaluated the clinical results of different surgical approach. Surgical or endoscopic repair was attempted in five AF patients who underwent RFCA. Atrio-esophageal fistula and mediastinal infection was not controlled in the patient who underwent endoscopic repair eventually died. Lethal cerebral air embolism occurred two days after surgery in a patient who underwent esophageal repair only. Primary surgical repair of both the left atrium (LA) and esophagus was performed in the remaining three patients. Among these three patients, two underwent external LA repair and the remaining had internal LA repair via open-heart surgery. External repair of the LA was unsuccessful and one patient dies and another had to undergo second operation with internal repair of the LA. The patient who underwent internal LA repair during the first operation survived without additional surgery. Furthermore, we applied veno-arterial extracorporeal membrane oxygenation (VA-ECMO) with artificial induction of ventricular fibrillation in this patient to prevent air and septic embolism and she had no neurologic sequelae. In summary, surgical correction can be considered preferentially to correct AEF. Open-heart surgical repair of LA from the internal side seems to be an acceptable surgical method. Application of VA-ECMO with artificial induction of ventricular fibrillation might be effective to prevent air and septic embolism.

Clinical outcomes of immunocompromised patients on extracorporeal membrane oxygenation support for severe acute respiratory failure.

OBJECTIVES: There are limited data regarding extracorporeal membrane oxygenation (ECMO) support in immunocompromised patients, despite an increase in ECMO use in patients with respiratory failure. The aim of this study was to investigate the clinical characteristics and outcomes of immunocompromised patients requiring ECMO support for severe acute respiratory failure. METHODS: Between January 2012 and December 2015, all consecutive adult patients with severe acute respiratory failure who underwent ECMO for respiratory support at 16 tertiary or university-affiliated hospitals in South Korea were enrolled retrospectively. The patients were divided into 2 groups based on the immunocompromised status at the time of ECMO initiation. In-hospital and 6-month mortalities were compared between the 2 groups. In addition, association of immunocompromised status with 6-month mortality was evaluated with logistic regression analysis. RESULTS: Among 461 patients, 118 (25.6%) were immunocompromised. Immunocompromised patients were younger and had lower haemoglobin and platelet counts than immunocompetent patients. Ventilatory parameters and the use of adjunctive/rescue therapies were similar between the 2 groups, but prone positioning was more commonly used in immunocompetent patients. Successful weaning rates from ECMO (46.6% vs 58.9%; P = 0.021) was lower and hospital mortality (66.1% vs 59.8%; P = 0.22) was higher in immunocompromised patients. In addition, immunocompromised status was associated with higher 6-month mortality (74.6% vs 64.7%, adjusted odds ratio 2.10, 95% confidence interval 1.02-4.35; P = 0.045). CONCLUSIONS: Immunocompromised patients treated with ECMO support for severe acute respiratory failure had poorer short- and long-term prognoses than did immunocompetent patients.

Rescue Extracorporeal Bypass to Prevent Atrioesophageal Fistula-related Air Embolism.

Atrioesophageal fistula (AEF) is a rare but disastrous complication encountered after radiofrequency catheter ablation for atrial fibrillation or flutter. Furthermore cerebral air embolism due to AEF is considered a strong predictor of mortality. In our case a patient presented with AEF and cerebral air embolism. As a rescue effort ventricular fibrillation was induced and sustained under venoarterial extracorporeal membrane oxygenation support until emergency AEF repair was feasible. Herein we report the successful use of the above measures to prevent further air embolism in a patient with radiofrequency catheter ablation-related AEF.

Renal hemodynamics by return cannular position of extracorporeal membrane oxygenation in swine.

BACKGROUND: Whether arterial return cannula position affects the kidney during Veno-Arterial extracorporeal membrane oxygenation (ECMO) is unclear. Therefore, we compared hemodynamic parameters and acute kidney injury (AKI) biomarkers between ascending aorta return (aECMO) and femoral artery return ECMO (fECMO) in swine to evaluate the effect of cannula position on the kidney. METHODS: A total of twelve swines were allocated randomly into two groups. ECMO was maintained for 6h. Hemodynamic parameters including mean arterial pressure (MAP), renal arterial flow rate (AF), energy equivalent pressure (EEP), and surplus hemodynamic energy (SHE) were measured at the left renal artery. For evaluation of kidney injury, samples were obtained for blood urea nitrogen, creatinine, cystatin C, and neutrophil gelatinase-associated lipocalin (before ECMO, and 1, 3, and 6 h after initiating ECMO). RESULTS: Before the start of ECMO, hemodynamic parameters were not different between the two groups. With regard to the rate of change before and after ECMO, the fECMO group showed a significantly higher increase in MAP, AF, and EEP and a greater decrease in SHE than the aECMO group (P<0.001). In inter-group analysis, no significant difference in time-dependent trends were observed for biochemical laboratory levels. CONCLUSIONS: fECMO support was associated with a higher energy profile at the renal artery than that with aECMO, whereas pulsatility was decreased.