TY - JOUR A1 - Radakovic, Dejan A1 - Penov, Kiril A1 - Hamouda, Khaled A1 - Madrahimov, Nodir A1 - Radakovic, Darko A1 - Bening, Constanze A1 - Leyh, Rainer G. A1 - Aleksic, Ivan T1 - Benefits of intra-aortic balloon pump support in patients with postcardiotomy shock requiring venoarterial extracorporeal membrane oxygenation JF - Life N2 - Background: The benefit of the combined use of an intra-aortic balloon pump (IABP) and venoarterial extracorporeal membrane oxygenation (VA-ECMO) for postcardiotomy shock remains unclear. We aimed to analyse the potential benefits and safety of combining these two devices. Methods: We enrolled 200 patients treated with either VA-ECMO only or in combination with IABP (ECMO-I group) between January 2012 and January 2021. To adjust the patients’ backgrounds, we used propensity score matching for additional analyses, resulting in 57 pairs. The primary endpoint was 30-day survival. Secondary endpoints included successful weaning and complication rates. We also analysed hemodynamic parameters in both groups. Results: After propensity score matching, 30-day survival was better in the ECMO-I group (log-rank p = 0.004). The ECMO-I and ECMO-only groups differed regarding the secondary endpoints, including successful weaning (50.9% and 26.3%, respectively; p = 0.012) and the need for continuous renal replacement therapy (28.1% and 50.9%, p = 0.021). Complication rates were not statistically different between the two groups. Conclusion: Compared to VA-ECMO alone, the combined use of VA-ECMO and IABP is beneficial regarding 30-day survival in selected patients with postcardiotomy shock; successful ECMO weaning and freedom from renal replacement therapy is more common in patients supported with VA-ECMO plus IABP. KW - postcardiotomy shock KW - VA-ECMO KW - IABP Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-286241 SN - 2075-1729 VL - 12 IS - 8 ER - TY - JOUR A1 - Penov, Kiril A1 - Radakovic, Dejan A1 - Madrahimov, Nodir A1 - Aleksic, Ivan T1 - Subacute Aortic Rupture Due to Mechanical Chest Compression with Indwelling Impella JF - The Thoracic and Cardiovascular Surgeon Reports N2 - Mechanical cardiopulmonary resuscitation (CPR) devices like Lund University Cardiopulmonary Assist System (LUCAS) cause more skeletal and visceral injuries than standard CPR. A 62-year-old woman with ST-elevation myocardial infarction was resuscitated with LUCAS and Impella CP for refractory cardiogenic shock during percutaneous coronary intervention. She suffered delayed ascending aortic rupture necessitating supracommissural ascending aortic replacement plus triple bypass grafting. Prolonged mechanical CPR with concomitant Impella may lead to aortic rupture. The combined use of LUCAS and Impella may have disastrous consequences. KW - cardiac catheterization/ intervention KW - shock (systemic, cardiac or circulatory) KW - circulatory assist devices Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-300174 SN - 2194-7635 VL - 11 IS - 1 SP - e64 EP - e66 ER - TY - JOUR A1 - Bening, Constanze A1 - Sales, Virna L. A1 - Alhussini, Khaled A1 - Radakovic, Dejan A1 - Cris Benitez, R. A1 - Madrahimov, Nodir A1 - Keller, Daria M. A1 - Leyh, Rainer T1 - Clinically inapparent right heart dysfunction is associated with reduced myofilament force development in coronary artery disease JF - BMC Cardiovascular Disorders N2 - Background Right ventricular dysfunction after CABG is associated with poor peri- and postoperative outcomes. We aimed to identify clinical and experimental predictors for preoperative inapparent right ventricular dysfunction and therefore hypothesized that reduced myofilament force development as well as altered levels of biomarkers might predict inapparent right ventricular dysfunction. Methods From 08/2016 to 02/2018, 218 patients scheduled for CABG were divided into two groups (TAPSE ≥ 20 mm, n = 178; TAPSE < 20 mm, n = 40). Baseline serum samples for biomarkers (Galectin, TGFß1, N Acyl-SDMA, Arginine, ADMA and Pentraxin-3), clinical laboratory and transthoracic echocardiographic parameters were evaluated. To examine the myocardial apparatus of the right ventricle intraoperative right auricular tissue was harvested for stepwise skinned fiber force measurements. Results Patients with TAPSE < 20 mm had a higher incidence of DM (55 vs. 34%, p = 0.018), preoperative AFib (43 vs. 16%, p < 0.001), reduced GFR (67 ± 18 vs. 77 ± 24 ml/min/1.73 m\(^2\), p = 0.013), larger LA area (22 ± 6 vs. 20 ± 5 cm\(^2\), p = 0.005) and reduced LVEF (50 vs. 55%, p = 0.008). Furthermore, higher serum ADMA (0.70 ± 0.13 vs. 0.65 ± 0.15 µmol/l, p = 0.046) and higher serum Pentraxin-3 levels (3371 ± 1068 vs. 2681 ± 1353 pg/dl, p = 0.004) were observed in these patients. Skinned fiber force measurements showed significant lower values at almost every step of calcium concentration (pCa 4.52 to pCa 5.5, p < 0.01 and pCa 5.75–6.0, p < 0.05). Multivariable analysis revealed DM (OR 2.53, CI 1.12–5.73, Euro Score II (OR 1.34, CI 1.02–1.78), preoperative AF (OR 4.86, CI 2.06–11.47), GFR (OR 7.72, CI 1.87–31.96), albumin (OR 1.56, CI 0.52–2.60), Pentraxin-3 (OR 19.68, CI 14.13–25.24), depressed LVEF (OR 8.61, CI 6.37–10.86), lower force values: (pCa 5.4; OR 2.34, CI 0.40–4.29 and pCa 5.2; OR 2.00, CI 0.39–3.60) as predictors for clinical inapparent right heart dysfunction. Conclusions These preliminary data showed that inapparent right heart dysfunction in CAD is already associated with reduced force development of the contractile apparatus. KW - skinned fiber KW - coronary artery bypass grafting KW - right heart impairment KW - pCa Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-259213 VL - 21 IS - 1 ER - TY - THES A1 - Radakovic, Dejan T1 - Development of a Dialysis Graft Based on Tissue Engineering Methods T1 - Entwicklung einer Dialysegraft basierend auf Tissue Engineering-Methoden N2 - Despite advancements of modern medicine, the number of patients with the the end-stage kidney disease keeps growing, and surgical procedures to establish and maintain a vascular access for hemodialysis are rising accordingly. Surgical access of choice remains autogenous arteriovenous fistula, whereas approach “fistula first at all costs” leads to failure in certain subgroups of patients. Modern synthetic vascular grafts fail to deliver long-term results comparable with AV fistula. With all that in mind, this work has an aim of developing a new alternative vascular graft, which can be used for hemodialysis access using the methods of TE, especially electrospinning technique. It is hypothesized that electrospun scaffold, made of PCL and collagen type I may assemble mechanical properties similar to native blood vessels. Seeding such electrospun scaffolds with human microvascular endothelial cells (hmvECs) and preconditioning with shear stress and continuous flow might achieve sufficient endothelial lining being able to resist acute thrombosis. One further topic considered on-site infections, which represents one of the most spread complications of dialysis therapy due to continuous needle punctures. The main hypothesis was that during electrospinning process, polymers can be blended with antibiotics with the aim of producing scaffolds with antimicrobial properties, which could lead to reducing the risk of on-site infection on one side, while not affecting the cell viability. N2 - Trotz der Fortschritte in der modernen Medizin wächst die Zahl der Patienten mit Nierenerkrankungen im Endstadium weiter, und die chirurgischen Verfahren zur Herstellung und Aufrechterhaltung eines Gefäßzugangs für die Hämodialyse nehmen entsprechend zu. Der chirurgische Zugang der Wahl bleibt eine autogene arteriovenöse Fistel, während der Ansatz „Fistel zuerst um jeden Preis“ bei bestimmten Untergruppen von Patienten zum Versagen führt. Moderne synthetische Gefäßtransplantate liefern keine mit AV-Fisteln vergleichbaren Langzeitergebnisse. Vor diesem Hintergrund zielt diese Arbeit darauf ab, ein neues alternatives Gefäßtransplantat zu entwickeln, das für den Zugang zur Hämodialyse unter Verwendung der TE-Methoden, insbesondere der Elektrospinntechnik, verwendet werden kann. Es wird angenommen, dass ein elektrogesponnenes Gerüst aus PCL und Kollagen Typ I ähnliche mechanische Eigenschaften wie native Blutgefäße aufweisen kann. Die Besiedelung solcher elektrogesponnener Gerüste mit menschlichen mikrovaskulären Endothelzellen (hmvECs) und das Vorkonditionieren mit Scherbeanspruchung und kontinuierlichem Fluss könnte eine ausreichende Endothelialisierung erreichen, um eine akute Thrombose vermeiden zu können. Ein weiteres Thema waren lokale Infektionen, die eine der am weitesten verbreiteten Komplikationen der Dialysetherapie aufgrund kontinuierlicher Nadelstiche darstellen. Die Haupthypothese war, dass Polymere während des Elektrospinnprozesses mit Antibiotika gemischt werden können, um Gerüste mit antimikrobiellen Eigenschaften herzustellen, die dazu führen können, dass das Risiko einer Infektion vor Ort auf einer Seite verringert wird, ohne die Lebensfähigkeit der Zellen zu beeinträchtigen. KW - Elektrospinnen KW - Tissue Engineering KW - Electrospinning Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-208492 ER - TY - JOUR A1 - Radakovic, Dejan A1 - Penov, Kiril A1 - Lazarus, Marc A1 - Madrahimov, Nodir A1 - Hamouda, Khaled A1 - Schimmer, Christoph A1 - Leyh, Rainer G. A1 - Bening, Constanze T1 - The completeness of the left atrial appendage amputation during routine cardiac surgery JF - BMC Cardiovascular Disorders N2 - Background Left atrial appendage (LAA) is the origin of most heart thrombi which can lead to stroke or other cerebrovascular event in patients with non-valvular atrial fibrillation (AF). This study aimed to prove safety and low complication rate of surgical LAA amputation using cut and sew technique with control of its effectiveness. Methods 303 patients who have undergone selective LAA amputation were enrolled in the study in a period from 10/17 to 08/20. The LAA amputation was performed concomitant to routine cardiac surgery on cardiopulmonary bypass with cardiac arrest with or without previous history of AF. The operative and clinical data were evaluated. Extent of LAA amputation was examined intraoperatively by transoesophageal echocardiography (TEE). Six months in follow up, the patients were controlled regarding clinical status and episodes of strokes. Results Average age of study population was 69.9 ± 19.2 and 81.9% of patients were male. In only three patients was residual stump after LAA amputation larger than 1 cm with average stump size 0.28 ± 0.34 cm. 3 patients (1%) developed postoperative bleeding. Postoperatively 77 (25.4%) patients developed postoperative AF (POAF), of which 29 (9.6%) still had AF at discharge. On 6 months follow up only 5 patients had NYHA class III and 1 NYHA class IV. Seven patients reported with leg oedema and no patient experienced any cerebrovascular event in early postoperative follow up. Conclusion LAA amputation can be performed safely and completely leaving minimal to no LAA residual stump. KW - left atrial appendage occlusion KW - cut and sew technique KW - atrial fibrillation Y1 - 2023 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-357376 VL - 23 ER - TY - JOUR A1 - Madrahimov, Nodir A1 - Mutsenko, Vitalii A1 - Natanov, Ruslan A1 - Radaković, Dejan A1 - Klapproth, André A1 - Hassan, Mohamed A1 - Rosenfeldt, Mathias A1 - Kleefeldt, Florian A1 - Aleksic, Ivan A1 - Ergün, Süleyman A1 - Otto, Christoph A1 - Leyh, Rainer G. A1 - Bening, Constanze T1 - Multiorgan recovery in a cadaver body using mild hypothermic ECMO treatment in a murine model JF - Intensive Care Medicine Experimental N2 - Background Transplant candidates on the waiting list are increasingly challenged by the lack of organs. Most of the organs can only be kept viable within very limited timeframes (e.g., mere 4–6 h for heart and lungs exposed to refrigeration temperatures ex vivo). Donation after circulatory death (DCD) using extracorporeal membrane oxygenation (ECMO) can significantly enlarge the donor pool, organ yield per donor, and shelf life. Nevertheless, clinical attempts to recover organs for transplantation after uncontrolled DCD are extremely complex and hardly reproducible. Therefore, as a preliminary strategy to fulfill this task, experimental protocols using feasible animal models are highly warranted. The primary aim of the study was to develop a model of ECMO-based cadaver organ recovery in mice. Our model mimics uncontrolled organ donation after an “out-of-hospital” sudden unexpected death with subsequent “in-hospital” cadaver management post-mortem. The secondary aim was to assess blood gas parameters, cardiac activity as well as overall organ state. The study protocol included post-mortem heparin–streptokinase administration 10 min after confirmed death induced by cervical dislocation under full anesthesia. After cannulation, veno-arterial ECMO (V–A ECMO) was started 1 h after death and continued for 2 h under mild hypothermic conditions followed by organ harvest. Pressure- and flow-controlled oxygenated blood-based reperfusion of a cadaver body was accompanied by blood gas analysis (BGA), electrocardiography, and histological evaluation of ischemia–reperfusion injury. For the first time, we designed and implemented, a not yet reported, miniaturized murine hemodialysis circuit for the treatment of severe hyperkalemia and metabolic acidosis post-mortem. Results BGA parameters confirmed profound ischemia typical for cadavers and incompatible with normal physiology, including extremely low blood pH, profound negative base excess, and enormously high levels of lactate. Two hours after ECMO implantation, blood pH values of a cadaver body restored from < 6.5 to 7.3 ± 0.05, pCO2 was lowered from > 130 to 41.7 ± 10.5 mmHg, sO2, base excess, and HCO3 were all elevated from below detection thresholds to 99.5 ± 0.6%, − 4 ± 6.2 and 22.0 ± 6.0 mmol/L, respectively (Student T test, p < 0.05). A substantial decrease in hyperlactatemia (from > 20 to 10.5 ± 1.7 mmol/L) and hyperkalemia (from > 9 to 6.9 ± 1.0 mmol/L) was observed when hemodialysis was implemented. On balance, the first signs of regained heart activity appeared on average 10 min after ECMO initiation without cardioplegia or any inotropic and vasopressor support. This was followed by restoration of myocardial contractility with a heart rate of up to 200 beats per minute (bpm) as detected by an electrocardiogram (ECG). Histological examinations revealed no evidence of heart injury 3 h post-mortem, whereas shock-specific morphological changes relevant to acute death and consequent cardiac/circulatory arrest were observed in the lungs, liver, and kidney of both control and ECMO-treated cadaver mice. Conclusions Thus, our model represents a promising approach to facilitate studying perspectives of cadaveric multiorgan recovery for transplantation. Moreover, it opens new possibilities for cadaver organ treatment to extend and potentiate donation and, hence, contribute to solving the organ shortage dilemma. KW - extracorporeal membrane oxygenation KW - cadaver multiorgan preservation KW - mild hypothermia KW - post-mortem heart recovery Y1 - 2023 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-357381 VL - 11 ER -