Routine Mediastinal Drainage Fluid Culture for Early Diagnosis of Poststernotomy Mediastinitis.

BACKGROUND: Early diagnosis of poststernotomy mediastinitis (PSM) is challenging. Since 2016, we have routinely performed mediastinal drainage fluid culture (MDFC) in patients undergoing sternotomy. This study aimed to determine the utility of MDFC for early diagnosis of PSM. METHODS: Between November 2016 and April 2020, we conducted MDFC in 1,012 patients on the third postoperative day and prospectively observed for PSM occurrence for 3 months. If bacteria were identified, additional MDFC or blood culture was performed to reduce the possibility of false positives. Based on MDFC results, the decision for early treatment for PSM was at the attending physician's discretion. RESULTS: Bacteria were identified in MDFC of 29 patients, eight of whom subsequently developed PSM. Among 983 patients with negative MDFC, only 15 developed PSM. In multivariate analysis, previous sternotomy history and positive MDFC were predictors of PSM. Positive MDFC was regarded as true positive if (1) PSM occurred subsequently, and/or (2) the same bacteria were identified in additional MDFC/blood culture. Non-occurrence of PSM in the absence of antibiotic treatment was regarded as false-positive MDFC. The sensitivity, specificity, and positive and negative predictive values of routine MDFC for diagnosis of mediastinal infection were 46.4, 99.0, 56.5, and 98.5%, respectively. When categorizing cases with positive MDFC based on the identified bacteria, the positive predictive value was highest (76.9%) when Staphylococci were identified. CONCLUSION: Routine MDFC after sternotomy can facilitate early diagnosis of PSM. Early treatment for PSM may be indicated in patients in whom Staphylococci are identified in the MDFC.

Correction to: A rare case of pericarditis and pleural empyema secondary to transdiaphragmatic extension of pyogenic liver abscess.

An amendment to this paper has been published and can be accessed via the original article.

A rare case of pericarditis and pleural empyema secondary to transdiaphragmatic extension of pyogenic liver abscess.

BACKGROUND: Transdiaphragmatic extension of pyogenic liver abscess is the rarest cause of pericarditis and pleural empyema. It is a rapidly progressive and highly lethal infection with mortality rates reaching 100% if left untreated. However, the transmission route, treatment methods and prognosis have not been well studied. CASE PRESENTATION: A 65-year-old male patient presented with a fever, dyspnea, and right upper quadrant abdominal pain. Computed tomography of the chest and abdomen showed huge liver abscess without full liquefaction in the left lobe, large amount of left pleural effusion, and mild pericardial effusion, and the patient was treated with parenteral antibiotics and pigtail insertion at the left pleura. However, four days later, cardiac tamponade was developed and surgical drainage of the abscess and pericardium was performed. Klebsiella pneumonia was isolated from pleural empyema. Twenty-five days after surgery, the patient was discharged without any complications. CONCLUSIONS: Herein, we report a rare case of pleural empyema and pericarditis in that resulted from the extension of huge pyogenic liver abscess. Early surgical treatment may have prevented progression of the pericarditis to the more dismal purulent pericarditis. We also review pertinent English literature on pericarditis as a complication of PLA.

Nosocomial Infection in Adult Patients Undergoing Veno-Arterial Extracorporeal Membrane Oxygenation.

Data on the frequency of nosocomial infections during extracorporeal membrane oxygenation (ECMO) in adult populations remain scarce. We investigated the risk factors for nosocomial infections in adult patients undergoing venoarterial ECMO (VA-ECMO) support. From January 2011 to December 2015, a total of 259 patients underwent ECMO. Of these, patients aged 17 years or less and patients undergoing ECMO for less than 48 hours were excluded. Of these, 61 patients diagnosed with cardiogenic shock were evaluated. Mean patient age was 60.6 ± 14.3 years and 21 (34.4%) patients were female. The mean preoperative Sequential Organ Failure Assessment (SOFA) score was 8.6 ± 2.2. The mean duration of ECMO support was 6.8 ± 7.4 days. The rates of successful ECMO weaning and survival to discharge were 44.3% and 31.1%, respectively. There were 18 nosocomial infections in 14 (23.0%) patients. These included respiratory tract infections in 9 cases and bloodstream infections in a further 9. In multivariate analysis, independent predictors of infection during ECMO were the preoperative creatinine level (hazard ratio [HR], 2.176; 95% confidence interval [CI], 1.065-4.447; P = 0.033) and the duration of ECMO support (HR, 1.400; 95% CI, 1.081-1.815; P = 0.011). A higher preoperative creatinine level and an extended duration of ECMO support are risk factors for infection. Therefore, to avoid the development of nosocomial infections, strategies to shorten the length of ECMO support should be applied whenever possible.

Immunological Analysis of Postoperative Delirium after Thoracic Aortic Surgery.

Background: Delirium is a recognized neurological complication following cardiac surgery and is associated with adverse clinical outcomes, including elevated mortality and prolonged hospitalization. While several clinical risk factors for post-cardiac surgery delirium have been identified, the pathophysiology related to the immune response remains unexamined. This study was conducted to investigate the immunological factors contributing to delirium in patients after thoracic aortic surgery. Methods: We retrospectively evaluated 43 consecutive patients who underwent thoracic aortic surgery between July 2017 and June 2018. These patients were categorized into 2 groups: those with delirium and those without it. All clinical characteristics were compared between groups. Blood samples were collected and tested on the day of admission, as well as on postoperative days 1, 3, 7, and 30. Levels of helper T cells (CD4), cytotoxic T cells (CD8), B cells (CD19), natural killer cells (CD56+CD16++), and monocytes (CD14+CD16-) were measured using flow cytometry. Results: The median patient age was 71 years (interquartile range, 56.7 to 79.0 years), and 21 of the patients (48.8%) were male. Preoperatively, most immune cell counts did not differ significantly between groups. However, the patients with delirium exhibited significantly higher levels of interleukin-6 and lower levels of tumor necrosis factor-alpha (TNF-α) than those without delirium (p<0.05). Multivariate analysis revealed that lower TNF-α levels were associated with an increased risk of postoperative delirium (p<0.05). Conclusion: Postoperative delirium may be linked to perioperative changes in immune cells and preoperative cytokine levels. Additional research is required to elucidate the pathophysiological mechanisms underlying delirium.

Long-Term Outcomes of the Maze Procedure Combined with Endoatriectomy for Patients with Calcified Left Atria.

PURPOSE: Left atrial calcification (LAC) is found in long-lasting rheumatic valvular disease and is almost always accompanied by atrial fibrillation (AF). In the presence of LAC, endoatriectomy is required when performing the maze procedure. However, the technical feasibility of endoatriectomy and the long-term outcomes of the maze procedure in patients with LAC are uncertain. METHODS: The medical records of 18 consecutive patients who underwent combined endoatriectomy and maze procedure were analyzed retrospectively. RESULTS: Accompanying operations were mitral valve replacement (n = 16) and commissurotomy (n = 2). There was 1 operative death from sepsis following mediastinitis. When patients were divided into "broad" (n = 11) and "limited" (n = 7) groups, with the extent of LAC either greater or less than half of the left atrium, respectively, there was no intergroup difference in postoperative complications. During follow-up (median, 11.4 years), AF recurred in 11 patients. At the last follow-up visits, electrocardiography revealed significantly fewer patients in the broad group maintaining sinus rhythm (1/11 vs 4/6, P = 0.03). The 10-year AF recurrence-free survival rates were 13.9% and 66.7% in the broad and limited groups, respectively (P = 0.01). CONCLUSIONS: The maze procedure combined with endoatriectomy seems technically feasible with acceptable long-term rhythm outcomes if the LAC extent is limited.

Hypoalbuminemia and Albumin Replacement during Extracorporeal Membrane Oxygenation in Patients with Cardiogenic Shock.

Background: Extracorporeal membrane oxygenation (ECMO) has been widely used in patients with cardiorespiratory failure. The serum albumin level is an important prognostic marker in critically ill patients. We evaluated the efficacy of using pre-ECMO serum albumin levels to predict 30-day mortality in patients with cardiogenic shock (CS) who underwent venoarterial (VA) ECMO. Methods: We reviewed the medical records of 114 adult patients who underwent VA-ECMO between March 2021 and September 2022. The patients were divided into survivors and non-survivors. Clinical data before and during ECMO were compared. Results: Patients' mean age was 67.8±13.6 years, and 36 (31.6%) were female. The proportion of survival to discharge was 48.6% (n=56). Cox regression analysis showed that the pre-ECMO albumin level independently predicted 30-day mortality (hazard ratio, 0.25; 95% confidence interval [CI], 0.11-0.59; p=0.002). The area under the receiver operating characteristic curve of albumin levels (pre-ECMO) was 0.73 (standard error [SE], 0.05; 95% CI, 0.63-0.81; p<0.001; cut-off value=3.4 g/dL). Kaplan-Meier survival analysis showed that the cumulative 30-day mortality was significantly higher in patients with a pre-ECMO albumin level ≤3.4 g/dL than in those with a level >3.4 g/dL (68.9% vs. 23.8%, p<0.001). As the adjusted amount of albumin infused increased, the possibility of 30-day mortality also increased (coefficient=0.140; SE, 0.037; p<0.001). Conclusion: Hypoalbuminemia during ECMO was associated with higher mortality, even with higher amounts of albumin replacement, in patients with CS who underwent VA-ECMO. Further studies are needed to predict the timing of albumin replacement during ECMO.

Aortic Valve Replacement by Subannular Endomyocardial Implantation of Valve Prosthesis in Behçet's Disease.

The novel anastomosis technique, "subannular endomyocardial implantation of valve prosthesis (SEIV)," focuses on excluding aortic annular tissue from suture line to avoid vascular inflammation in Behçet's disease (BD). We aimed to validate that SEIV could prevent prosthetic valve detachment (PVD) after aortic valve replacement (AVR) in BD patients and retrospectively analyzed the medical records of five BD patients who underwent AVR. There was no operative death. Two complete atrioventricular blocks occurred; in one of them, a permanent pacemaker (PPM) was inserted before discharge. The other one was discharged without a PPM; however, he died suddenly 32 days postoperatively. The median follow-up period was 3.3 years. There was a case of PVD with newly developed Valsalva sinus aneurysm requiring the Bentall operation at 3.6 years postoperatively. In conclusion, SEIV might prevent PVD in BD patients who underwent AVR. However, aortic root pathology related to BD activity and resulting PVD may occur later.

High incidence of acute kidney injury in extracorporeal resuscitation, Leading to poor prognosis.

Background: Extracorporeal membrane oxygenation (ECMO) patients have a high incidence of acute kidney injury (AKI). Extracorporeal cardiopulmonary resuscitation (ECPR) patients are more likely to develop AKI than ECMO patients because of serious injury during cardiac arrest (CA). Objectives: This study aims to assess the occurrence and outcomes of AKI in ECPR and ECMO, and to identify specific risk factors and clinical implications of AKI in ECPR. Methods: This is a retrospective observational study from a single tertiary care hospital in Gwangju, Korea. Adults (≥18 years) who received ECMO with cardiac etiology in the emergency and inpatient departments from January 2015 to December 2021 were included. The patients (n = 169) were divided into two groups, ECPR and ECMO without CA, and the occurrence of AKI was investigated. The primary outcome of the study was in-hospital mortality, and the secondary outcomes were six-month cerebral performance category (CPC) and AKI during hospitalization. Results: The incidence of AKI was significantly higher with ECPR (67.5 %) than with ECMO without CA (38.4 %). ECPR was statistically significant for Expire (adjusted OR (aOR) 2.45, 95 % CI 1.28-4.66) and Poor CPC (2.59, 1.32-5.09). AKI was also statistically significant for Expire (6.69, 3.37-13.29) and Poor CPC (5.45, 2.73-10.88). AKI was the determining factor for the outcomes of ECPR (p = 0.01). Conclusions: ECPR patients are more likely to develop AKI than ECMO without CA patients. In ECPR patients, AKI leads to poor outcomes. Therefore, clinicians should be careful not to develop AKI in ECPR patients.

Successful treatment with femoro-femoral venovenous extracorporeal membrane oxygenation in traumatic tracheal injury: a case report.

BACKGROUND: Traumatic tracheal injury is a rare type of trauma. In this type of injury, catastrophes may occur owing to a failure to secure the patient's airway. Extracorporeal membrane oxygenation (ECMO) is rescue therapy available for the treatment of urgent cardiorespiratory distress until the patient's vital signs have stabilized. The various applications of ECMO configurations have expanded the scope for this therapy. CASE PRESENTATION: We describe the case of a 66-year-old man with tracheal rupture with thyroid cartilage fracture due to cultivator handle who was treated with veno-venous ECMO. This case reflects the role and limitations of veno-venous ECMO, in which patient survival was possible with a bi-femoral configuration while also ensuring a clear airway. CONCLUSION: We shared our experience with bi-femoral veno-venous ECMO as a therapeutic option to contribute to choosing an appropriate approach. Based on our review of the literature, the present case was an uncommon report of survival after tracheal rupture due to trauma without other complications.

Open surgical treatment of subclavian artery pseudoaneurysm after endovascular repair: a case report.

BACKGROUND: Subclavian artery aneurysms are rare but may cause life-threatening complications. Surgical repair has been performed as a treatment of choice, but recently, with the development of endovascular treatment, many endovascular repairs have been performed to prevent surgical complications. CASE PRESENTATION: A patient undergoing endovascular repair with a subclavian artery aneurysm was diagnosed with a type II endoleak with an enlarged aneurysmal sac. Surgical repair was performed to remove the aneurysmal sac compressing the adjacent organs. CONCLUSIONS: The highly mobile subclavian artery has abundant collaterals. Therefore, regular follow-up is essential for endovascular repair. Surgical repair is effective when adjacent organs are compressed by the aneurysm sac.

Prediction of 6-Month Mortality Using Pre-Extracorporeal Membrane Oxygenation Lactate in Patients with Acute Coronary Syndrome Undergoing Veno-Arterial-Extracorporeal Membrane Oxygenation.

BACKGROUND: The effectiveness of extracorporeal membrane oxygenation (ECMO) for patients with refractory cardiogenic shock or cardiac arrest is being established, and serum lactate is well known as a biomarker of end-organ perfusion. We evaluated the efficacy of pre-ECMO lactate for predicting 6-month survival in patients with acute coronary syndrome (ACS) undergoing ECMO. METHODS: We reviewed the medical records of 148 patients who underwent veno-arterial (VA) ECMO for ACS between January 2015 and June 2020. These patients were divided into survivors and non-survivors based on 6-month survival. All clinical data before and during ECMO were compared between the 2 groups. RESULTS: Patients' mean age was 66.0±10.5 years, and 116 (78.4%) were men. The total survival rate was 45.9% (n=68). Cox regression analysis showed that the pre-ECMO lactate level was an independent predictor of 6-month mortality (hazard ratio, 1.210; 95% confidence interval [CI], 1.064-1.376; p=0.004). The area under the receiver operating characteristic curve of pre-ECMO lactate was 0.64 (95% CI, 0.56-0.72; p=0.002; cut-off value=9.8 mmol/L). Kaplan-Meier survival analysis showed that the cumulative survival rate at 6 months was significantly higher among patients with a pre-ECMO lactate level of 9.8 mmol/L or less than among those with a level exceeding 9.8 mmol/L (57.3% vs. 31.8%, p=0.0008). CONCLUSION: A pre-ECMO lactate of 9.8 mmol/L or less may predict a favorable outcome at 6 months in ACS patients undergoing VA-ECMO. Further research aiming to improve the accuracy of predictions of reversibility in patients with high pre-ECMO lactate levels is essential.

A Comparative Study of an Anti-Thrombotic Small-Diameter Vascular Graft with Commercially Available e-PTFE Graft in a Porcine Carotid Model.

BACKGROUND: We have designed a reinforced drug-loaded vascular graft composed of polycaprolactone (PCL) and polydioxanone (PDO) via a combination of electrospinning/3D printing approaches. To evaluate its potential for clinical application, we compared the in vivo blood compatibility and performance of PCL/PDO + 10%DY grafts doped with an antithrombotic drug (dipyridamole) with a commercial expanded polytetrafluoroethylene (e-PTFE) graft in a porcine model. METHODS: A total of 10 pigs (weight: 25-35 kg) were used in this study. We made a new 5-mm graft with PCL/PDO composite nanofiber via the electrospinning technique. We simultaneously implanted a commercially available e-PTFE graft (n = 5) and our PCL/PDO + 10%DY graft (n = 5) into the carotid arteries of the pigs. No anticoagulant/antiplatelet agent was administered during the follow-up period, and ultrasonography was performed weekly to confirm the patency of the two grafts in vivo. Four weeks later, we explanted and compared the performance of the two grafts by histological analysis and scanning electron microscopy (SEM). RESULTS: No complications, such as sweating on the graft or significant bleeding from the needle hole site, were seen in the PCL/PDO + 10%DY graft immediately after implantation. Serial ultrasonographic examination and immunohistochemical analysis demonstrated that PCL/PDO + 10%DY grafts showed normal physiological blood flow and minimal lumen reduction, and pulsed synchronously with the native artery at 4 weeks after implantation. However, all e-PTFE grafts occluded within the study period. The luminal surface of the PCL/PDO + 10%DY graft in the transitional zone was fully covered with endothelial cells as observed by SEM. CONCLUSION: The PCL/PDO + 10%DY graft was well tolerated, and no adverse tissue reaction was observed in porcine carotid models during the short-term follow-up. Colonization of the graft by host endothelial and smooth muscle cells coupled with substantial extracellular matrix production marked the regenerative capability. Thus, this material may be an ideal substitute for vascular reconstruction and bypass surgeries. Long-term observations will be necessary to determine the anti-thrombotic and remodeling potential of this device.

Transcatheter aortic valve replacement via a transsubclavian approach in a patient with severe aortic stenosis who had previously undergone kidney transplantation: A case report.

RATIONALE: Although the transfemoral approach is the gold standard for transcatheter aortic valve replacement (TAVR), it is not feasible in a considerable number of patients. We report a case of successful transsubclavian TAVR (TS-TAVR) in a patient with severe aortic stenosis (AS) who was ineligible for transfemoral TAVR because she was a kidney transplant recipient. PATIENT CONCERNS: A 72-year-old Korean woman, who had previously undergone kidney transplantation in the right iliac fossa for end-stage kidney disease, was admitted to our center with dyspnea. Upon auscultation, grade IV systolic murmurs were detected in both upper sternal borders and the left lower sternal border, suggestive of valvular heart disease. DIAGNOSIS: Two-dimensional transthoracic echocardiography revealed heavy calcification of the aortic valve with a high peak velocity (4.54 m/s) and mean pressure gradient (48.49 mm Hg), indicative of severe AS. INTERVENTIONS: TS-TAVR was performed by a heart team comprised of interventional cardiologists, cardiac surgeons, and anesthesiologists. A self-expandable valve prosthesis (CoreValveTM Evolut RTM, Medtronic Inc., Minneapolis, MN) was successfully deployed via the left subclavian artery. OUTCOMES: Post-TAVR 2-dimensional transthoracic echocardiography demonstrated a well-functioning valve with mild paravalvular leakage. The peak velocity had declined from 4.54 m/s to 2.22 to 2.24 m/s, and the mean pressure gradient had declined from 48.49 to 8.57-9.61 mmHg. The patient was discharged successfully and uneventfully. LESSONS: Because kidney transplant recipients with severe AS are considered poor candidates for transfemoral TAVR, TS-TAVR is a suitable alternative to consider.

Viability of Mesenchymal Stem Cells in an Ex Vivo Circulation System.

Extracorporeal membrane oxygenation (ECMO) is a well-known therapy for refractory cardiac and respiratory failure. Stem cell therapy has been investigated as an adjunctive treatment for use during ECMO, but little is known about the viability of stem cells during ECMO support. We evaluated the viability and activity of mesenchymal stem cells (MSCs) in ex vivo circulation (EVC) conditions. The experimental groups were divided into two subgroups: EVC with oxygenator (OXY group) and EVC without oxygenator (Non-OXY group). Mesenchymal stem cells (1.0 × 10) were injected into the EVC system. Cell counting, a lactate dehydrogenase (LDH) cytotoxicity assay, and the mitochondrial functions of viable MSCs were analyzed. The post-EVC oxygen consumption rate (OCR) was significantly lower than the pre-EVC OCR, regardless of whether the oxygenator was used. The LDH levels were significantly higher in the OXY group than in the Non-OXY group. The cellular loss was mainly due to lysis of the cells whereas the loss of cellular activity was attributed to the nonphysiologic condition itself, as well as the oxygenator. We concluded that direct infusion of MSCs during ECMO support did not serve as adjunctive therapy. Further studies are needed to improve the viability in an ECMO setting.

Tension pneumothorax after endoscopic retrograde pancreatocholangiogram.

We report a case of tension pneumothorax after an endoscopic sphincterotomy. A 78-yr-old woman presented with progressing dyspnea. She had undergone an endoscopic retrograde cholangiopancreatogram three days before due to acute cholecystitis. She underwent endoscopic sphincterotomy for stone extraction, but the procedure failed. On arrival to our hospital, she complained about severe dyspnea and she had subcutaneous emphysema. A computed tomogram scan revealed severe subcutaneous emphysema, right-side tension pneumothorax, and pneumoretroperitoneum. Contrast media injected through a transnasal biliary drainage catheter spilled from the second portion of the duodenum. A second abdominal computed tomogram showed multiple air densities in the retroperitoneum and peritoneal cavity, which were consistent with panperitonitis. We recommended an emergent laparotomic exploration, but the patient's guardians refused. She died eventually due to septic shock. Endoscopic retrograde cholangiopancreatogram is a popular procedure for biliary and pancreatic diseases, but it can cause severe complications such as intestinal perforation. Besides perforations, air can spread through the abdominal cavity, retroperitoneum, mediastinum, and the neck soft tissue, eventually causing pneumothorax. Early recognition and appropriate management is crucial to an optimal output of gastrointestinal perforation and pneumothorax.

Supraclavicular transposition of aberrant left vertebral artery for hybrid treatment of aortic arch aneurysm: a case report.

BACKGROUND: Vertebral artery variations are common in thoracic aortic patients. If patients have the aberrant left vertebral artery, the more difficult to determine the treatment modality. CASE PRESENTATION: We report the case of a 63-year-old man with an aberrant left vertebral artery originating from an aneurysmal aortic arch. The patient underwent a successful hybrid thoracic endovascular aortic repair after aortic arch debranching and transposition of the aberrant left vertebral artery to the left common carotid artery through a supraclavicular incision without sternotomy. CONCLUSIONS: The aberrant left vertebral artery originating from the aortic arch can be safely transposed to the left common carotid artery through a supraclavicular approach.

Early Antithrombotic Therapy after Bioprosthetic Aortic Valve Replacement in Elderly Patients: A Single-Center Experience.

PURPOSE: Early antithrombotic therapy after bioprosthetic aortic valve replacement (AVR) is controversial. This study aimed to retrospectively compare between warfarin and aspirin treatment in the 3 months after bioprosthetic AVR for elderly patients more than 60 years old, and to determine the optimal antithrombotic therapy. METHODS: This retrospective study included 479 patients in single center from January 1994 to June 2014. Patients were divided into two groups (Wa group, warfarin; As group, aspirin). We searched our computerized clinical database for thromboembolic or bleeding events. Propensity score analysis was conducted to adjust for selection bias. RESULTS: All patients, except one patient, were followed-up in the out-patient department for 3 months after the operation. In all, 86 propensity-matched patient-pairs were derived. Early operative outcomes were similar in both the groups. There are one patient of thromboembolic event and three patients of bleeding events, but the prevalence was not significantly different (p >0.999). CONCLUSION: The incidence of thromboembolic and bleeding events during early 3 months after bioprosthetic AVR were similar in Wa and As groups. If the patient does not have indications of warfarin, early antithrombotic therapy with aspirin only may be easier and more feasible for elderly patients.