Dilated (DCM) and ischemic cardiomyopathies (ICM) are associated with cardiac remodeling, where the ubiquitin–proteasome system (UPS) holds a central role. Little is known about the UPS and its alterations in patients suffering from DCM or ICM. The aim of this study is to characterize the UPS activity in human heart tissue from cardiomyopathy patients. Myocardial tissue from ICM (n = 23), DCM (n = 28), and control (n = 14) patients were used to quantify ubiquitinylated proteins, E3-ubiquitin-ligases muscle-atrophy-F-box (MAFbx)/atrogin-1, muscle-RING-finger-1 (MuRF1), and eukaryotic-translation-initiation-factor-4E (eIF4E), by Western blot. Furthermore, the proteasomal chymotrypsin-like and trypsin-like peptidase activities were determined fluorometrically. Enzyme activity of NAD(P)H oxidase was assessed as an index of reactive oxygen species production. The chymotrypsin- (p = 0.71) and caspase-like proteasomal activity (p = 0.93) was similar between the groups. Trypsin-like proteasomal activity was lower in ICM (0.78 ± 0.11 µU/mg) compared to DCM (1.06 ± 0.08 µU/mg) and control (1.00 ± 0.06 µU/mg; p = 0.06) samples. Decreased ubiquitin expression in both cardiomyopathy groups (ICM vs. control: p < 0.001; DCM vs. control: p < 0.001), as well as less ubiquitin-positive deposits in ICM-damaged tissue (ICM: 4.19% ± 0.60%, control: 6.28% ± 0.40%, p = 0.022), were detected. E3-ligase MuRF1 protein expression (p = 0.62), NADPH-oxidase activity (p = 0.63), and AIF-positive cells (p = 0.50). Statistical trends were detected for reduced MAFbx protein expression in the DCM-group (p = 0.07). Different levels of UPS components, E3 ligases, and UPS activation markers were observed in myocardial tissue from patients affected by DCM and ICM, suggesting differential involvement of the UPS in the underlying pathologies.
Mechanical circulatory support has proven effective in managing postcardiotomy cardiogenic shock by stabilizing patients’ hemodynamics and ensuring adequate organ perfusion. Among the available device modalities, the combination of extracorporeal life support and a microaxial flow pump for left ventricular unloading has emerged as a valuable tool in the surgical armamentarium. In this publication, we provide recommendations for the application and weaning of temporary mechanical circulatory support in cardiogenic shock patients, derived from a consensus among leading cardiac centers in German-speaking countries.
Background and Objectives: To analyze the patient outcome and complication rate of axillary artery cannulation for veno-arterial extracorporeal membrane oxygenation (VA-ECMO) in patients who could not be weaned from cardiopulmonary bypass after cardiothoracic surgery. Materials and Methods: We analyzed the data of 179 patients who were supported with VA-ECMO with femoral–axillary access (FA VA-ECMO) after cardiothoracic surgery between January 2014 and January 2019 in our department. Patients requiring central aortic cannulation and patients with respiratory failure requiring veno-venous ECMO were excluded. Primary outcomes were in-hospital mortality and 1-year survival rate of patients who were weaned from VA-ECMO support. Secondary outcomes were cannulation-related complications at the axillary site, VA-ECMO-related complications, and systemic complications. Results: In our cohort, 60 (33.5%) patients were female. Mean age was 67.0 ± 10.9 years. Overall, 78 (43.5%) patients were operated upon electively, 37 (20.7%) patients underwent urgent surgery, and 64 (35.8%) patients underwent emergency surgical treatment. Sixty-seven patients (37.4%) were resuscitated preoperatively. The mean duration of VA-ECMO support was 8.4 ± 5.1 days. Weaning from VA-ECMO was successful in 87 (48.6%) patients; 62 (34.6%) patients survived the hospital stay. The 1-year survival rate was 74%. Subclavian bleeding occurred in 24 (13.4%) patients, femoral bleeding in 4 (2.2%) patients, ischemia of the upper limb in 11 (6.1%) patients, intracerebral bleeding in 9 (5%) patients, and stroke in 19 (10.6%) patients. Conclusions: In patients with acute LV dysfunction after cardiothoracic surgery who cannot be weaned from cardiopulmonary bypass, right axillary artery cannulation is a safe and reliable method for VA-ECMO support with an acceptable complication rate.
Background: Aortic valve and root replacement (AVRR) is a standardised procedure to treat patients with aortic valve and root disease. In centres with a well-established aortic valve and root repair program (valve repairs and Ross operations), only patients with very complex conditions receive AVRR; this procedure uses a mechanical or biological composite valve graft (modified Bentall–de Bono procedure). The aim of the study was to evaluate the short- and long-term results after AVRR in a high-risk population with complex pathologies. Methods: Between 2005 and 2018, a total of 273 consecutive patients (mean age 64 ± 12.8 years; 23% female) received AVRR. The indication for surgery was an acute type A aortic dissection in 18%, infective endocarditis in 36% and other pathologies in 46% patients; 39% were redo procedures. The median EuroSCORE II was 11.65% (range 1.48–95.63%). Concomitant surgery was required in 157 patients (58%). Results: The follow-up extended to 5.2 years (range 0.1–15 years) and it was complete in 96% of the patients. The 30-day mortality was 17%. The overall estimated survival at 5 and 10 years was 65% ± 3% and 49% ± 4%, respectively. Univariate and multivariate logistic regression analyses revealed the following risk factors for survival: perioperative neurological dysfunction (OR 5.45), peripheral artery disease (OR 4.4) and re-exploration for bleeding (OR 3.37). Conclusions: AVRR can be performed with acceptable short- and long-term results in a sick patient population. The Bentall–De Bono procedure may be determined to be suitable for only elderly or high-risk patients. Any other patients should receive an AV repair or the Ross procedure in well-established centres.
27 July 2012 in European Journal of Cardio-Thoracic Surgery
Selective cerebral perfusion (SCP) is commonly applied during the correction of complex congenital cardiac defects. In this study, we assessed the impact of different flow levels of SCP on potential brain ischaemia. Fifteen piglets (7–10 kg, age 3–4 weeks) received SCP via the right common carotid artery during cardiopulmonary bypass at 25°C for 90 min. Regular brain perfusion (1 ml/g brain weight/min), moderate hypoperfusion (0.5 ml/g/min) and extensive hypoperfusion (0.25 ml/g/min) were evaluated. Clinical parameters and tissue oxygenation index (TOI) were registered online until 3 h of reperfusion. Hematoxylin and eosin (HE) staining and immunohistological analyses for apoptosis inducing factor (AIF) and nitrotyrosine (NO-Tyr) were performed on sections of the hippocampus. Intracerebral pressure remained stable throughout the study. Haemodynamic parameters, blood gas and lactate measurements were stable until the end of the study. Extensive hypoperfusion led to a moderate reduction of TOI. NO-Tyr immuno-positive cells were 15.7% at regular cerebral perfusion, 23.9% at moderate hypoperfusion (P = n.s.) and 46.1% at extensive hypoperfusion (P < 0.05). AIF immuno-positive nuclei were present in 8.3% of the hippocampus cells after regular perfusion, in 10.8% after moderate hypoperfusion (P = n.s.) and in 17.9% after extensive hypoperfusion (P < 0.05). SCP using a moderate SCP flow regime demonstrates comparable results to normal brain perfusion while after extensive hypoperfusion significant morphological brain injury could be found. Thus moderate, but not extensive, hypoperfusion might have the potential to prevent perfusion-related cerebral oedema and an increasing risk of brain injury.
The hemodynamic stabilization of patients after complex cardiac surgery is a daily challenge. The use of high doses of catecholamines is common but has potential adverse effects. Glibenclamide, a KATP blocker, seems to attenuate vasoplegia in different animal models of septic shock. Therefore, the aim of this study was to investigate the impact of Glibenclamide on the vasoplegic syndrome after cardiopulmonary bypass in a porcine model. In this experimental study, 20 landrace pigs were randomized into two groups and examined: In the control group, standard medical therapy, including norepinephrine, was used, and in the study group standard medical therapy plus additional Glibenclamide was administered. Following general anesthesia, prolonged cardiopulmonary bypass and aortic cross-clamping was performed. In the study group, Glibenclamide was administered 45 min after weaning from cardiopulmonary bypass. The dosage used was 10 mg/kg as a bolus, followed by a continuous infusion of 10 mg/kg/h. Hemodynamic and laboratory measurements were performed. Glibenclamide had a relevant effect on circulatory parameters. With increasing vascular resistance and blood pressure, norepinephrine was able to be reduced. While the heart rate dropped to physiological levels, the cardiac index decreased as well. The results lead to the conclusion that Glibenclamide was able to break through vasoplegic syndrome and could therefore serve as a potent drug to stabilize patients after cardiac surgery.