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 - TY - JOUR A1 - Bening, C. A1 - Genser, B. A1 - Keller, D. A1 - Müller-Altrock, S. A1 - Radakovic, D. A1 - Penov, K. A1 - Hassan, M. A1 - Aleksic, I. A1 - Leyh, R. A1 - Madrahimov, N. T1 - Impact of estradiol, testosterone and their ratio on left and right auricular myofilament function in male and female patients undergoing coronary artery bypass grafting JF - BMC Cardiovascular Disorders N2 - Background The impact of sex hormones on right and left auricular contractile apparatus function is largely unknown. We evaluated the impact of sex hormones on left and right heart contractility at the level of myocardial filaments harvested from left and right auricles during elective coronary artery bypass surgery. Methods 150 patients (132 male; 18 female) were enrolled. Preoperative testosterone and estradiol levels were measured with Immunoassay. Calcium induced force measurements were performed with left- and right auricular myofilaments in a skinned fiber model. Correlation analysis was used for comparison of force values and levels of sex hormones and their ratio. Results Low testosterone was associated with higher top force values in right-sided myofilaments but not in left-sided myofilaments for both sexes (p = 0.000 in males, p = 0.001 in females). Low estradiol levels were associated with higher top force values in right-sided myofilaments (p 0.000) in females and only borderline significantly associated with higher top force values in males (p 0.056). In females, low estradiol levels correlated with higher top force values in left sided myofilaments (p 0.000). In males, higher Estradiol/Testosterone ratio (E/T ratio) was only associated with higher top force values from right auricular myofilaments (p 0.04) In contrast, in females higher E/T ratio was associated with lower right auricular myofilament top force values (p 0.03) and higher top force values in left-sided myofilaments (p 0.000). Conclusions This study shows that patients’ comorbidities influence left and right sided contractility and may blur results concerning influence of sex hormones if not eliminated. A sex hormone dependent influence is obvious with different effects on the left and right ventricle. The E/T ratio and its impact on myofilament top force showed divergent results between genders, and may partially explain gender differences in patients with cardiovascular disease. KW - sex differences KW - E/T ratio KW - 17ßEstradiol KW - testosterone KW - skinned fiber Y1 - 2023 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-357368 VL - 23 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 - Greite, Robert A1 - Störmer, Johanna A1 - Gueler, Faikah A1 - Khalikov, Rasul A1 - Haverich, Axel A1 - Kühn, Christian A1 - Madrahimov, Nodir A1 - Natanov, Ruslan T1 - Different acute kidney injury patterns after renal ischemia reperfusion injury and extracorporeal membrane oxygenation in mice JF - International Journal of Molecular Sciences N2 - The use of extracorporeal membrane oxygenation (ECMO) is associated with acute kidney injury (AKI) in thoracic organ transplantation. However, multiple other factors contribute to AKI development after these procedures such as renal ischemia-reperfusion injury (IRI) due to hypo-perfusion of the kidney during surgery. In this study, we aimed to explore the kidney injury patterns in mouse models of ECMO and renal IRI. Kidneys of C57BL/6 mice were examined after moderate (35 min) and severe (45 min) unilateral transient renal pedicle clamping and 2 h of veno-venous ECMO. Renal injury markers, neutrophil infiltration, tubular transport function, pro-inflammatory cytokines, and renal heme oxygenase-1 (HO-1) expression were determined by immunofluorescence and qPCR. Both procedures caused AKI, but with different injury patterns. Severe neutrophil infiltration of the kidney was evident after renal IRI, but not following ECMO. Tubular transport function was severely impaired after renal IRI, but preserved in the ECMO group. Both procedures caused upregulation of pro-inflammatory cytokines in the renal tissue, but with different time kinetics. After ECMO, but not IRI, HO-1 was strongly induced in tubular cells indicating contact with hemolysis-derived proteins. After IRI, HO-1 was expressed on infiltrating myeloid cells in the tubulo-interstitial space. In conclusion, renal IRI and ECMO both caused AKI, but kidney damage after renal IRI was more pronounced including severe neutrophil infiltration and tubular transport impairment. Enhanced HO-1 expression in tubular cells after ECMO encourages limitation of hemolysis as a therapeutic approach to reduce ECMO-associated AKI. KW - acute kidney injury KW - extracorporeal membrane oxygenation KW - heme oxygenase-1 KW - renal inflammation Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-288282 SN - 1422-0067 VL - 23 IS - 19 ER - TY - JOUR A1 - Leistner, Marcus A1 - Sommer, Stefanie A1 - Kanofsky, Peer A1 - Leyh, Rainer A1 - Sommer, Sebastian-Patrick T1 - Ischemia time impacts on respiratory chain functions and Ca\(^{2+}\)-handling of cardiac subsarcolemmal mitochondria subjected to ischemia reperfusion injury JF - Journal of Cardiothoracic Surgery N2 - Background Mitochondrial impairment can result from myocardial ischemia reperfusion injury (IR). Despite cardioplegic arrest, IR-associated cardiodepression is a major problem in heart surgery. We determined the effect of increasing ischemia time on the respiratory chain (RC) function, the inner membrane polarization and Ca\(^{2+}\) homeostasis of rat cardiac subsarcolemmal mitochondria (SSM). Methods Wistar rat hearts were divided into 4 groups of stop-flow induced warm global IR using a pressure-controlled Langendorff system: 0, 15, 30 and 40 min of ischemia with 30 min of reperfusion, respectively. Myocardial contractility was determined from left ventricular pressure records (dP/dt, dPmax) with an intraventricular balloon. Following reperfusion, SSM were isolated and analyzed regarding electron transport chain (ETC) coupling by polarography (Clark-Type electrode), membrane polarization (JC1 fluorescence) and Ca2+-handling in terms of Ca\(^{2+}\)-induced swelling and Ca\(^{2+}\)-uptake/release (Calcium Green-5 N® fluorescence). Results LV contractility and systolic pressure during reperfusion were impaired by increasing ischemic times. Ischemia reduced ETC oxygen consumption in IR40/30 compared to IR0/30 at complex I-V (8.1 ± 1.2 vs. 18.2 ± 2.0 nmol/min) and II-IV/V (16.4 ± 2.6/14.8 ± 2.3 vs. 2.3 ± 0.6 nmol/min) in state 3 respiration (p < 0.01). Relative membrane potential revealed a distinct hyperpolarization in IR30/30 and IR40/30 (171.5 ± 17.4% and 170.9 ± 13.5%) compared to IR0/30 (p < 0.01), wearing off swiftly after CCCP-induced uncoupling. Excess mitochondrial permeability transition pore (mPTP)-gated Ca\(^{2+}\)-induced swelling was recorded in all groups and was most pronounced in IR40/30. Pyruvate addition for mPTP blocking strongly reduced SSM swelling in IR40/30 (relative AUC, ± pyruvate; IR0/30: 1.00 vs. 0.61, IR15/30: 1.68 vs. 1.00, IR30/30: 1.42 vs. 0.75, IR40/30: 1.97 vs. 0.85; p < 0.01). Ca2+-uptake remained unaffected by previous IR. Though Ca\(^{2+}\)-release was delayed for ≥30 min of ischemia (p < 0.01), Ca\(^{2+}\) retention was highest in IR15/30 (RFU; IR0/30: 6.3 ± 3.6, IR 15/30 42.9 ± 5.0, IR30/30 15.9 ± 3.8, IR40/30 11.5 ± 6.6; p ≤ 0.01 for IR15/30 against all other groups). Conclusions Ischemia prolongation in IR injury gradually impaired SSM in terms of respiratory chain function and Ca\(^{2+}\)-homeostasis. Membrane hyperpolarization appears to be responsible for impaired Ca2+-cycling and ETC function. Ischemia time should be considered an important factor influencing IR experimental data on subsarcolemmal mitochondria. Periods of warm global ischemia should be minimized during cardiac surgery to avoid excessive damage to SSMs. KW - subsarcolemmal mitochondria KW - ischemia reperfusion injury KW - ischemia time Y1 - 2019 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-236455 VL - 14 ER - 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 - Yurdadogan, Tino A1 - Malsch, Carolin A1 - Kotseva, Kornelia A1 - Wood, David A1 - Leyh, Rainer A1 - Ertl, Georg A1 - Karmann, Wolfgang A1 - Müller-Scholden, Lara A1 - Morbach, Caroline A1 - Breuning, Margret A1 - Wagner, Martin A1 - Gelbrich, Götz A1 - Bots, Michiel L. A1 - Heuschmann, Peter U. A1 - Störk, Stefan T1 - Functional versus morphological assessment of vascular age in patients with coronary heart disease JF - Scientific Reports N2 - Communicating cardiovascular risk based on individual vascular age (VA) is a well acknowledged concept in patient education and disease prevention. VA may be derived functionally, e.g. by measurement of pulse wave velocity (PWV), or morphologically, e.g. by assessment of carotid intima-media thickness (cIMT). The purpose of this study was to investigate whether both approaches produce similar results. Within the context of the German subset of the EUROASPIRE IV survey, 501 patients with coronary heart disease underwent (a) oscillometric PWV measurement at the aortic, carotid-femoral and brachial-ankle site (PWVao, PWVcf, PWVba) and derivation of the aortic augmentation index (AIao); (b) bilateral cIMT assessment by high-resolution ultrasound at three sites (common, bulb, internal). Respective VA was calculated using published equations. According to VA derived from PWV, most patients exhibited values below chronological age indicating a counterintuitive healthier-than-anticipated vascular status: for VA(PWVao) in 68% of patients; for VA\(_{AIao}\) in 52% of patients. By contrast, VA derived from cIMT delivered opposite results: e.g. according to VA\(_{total-cIMT}\) accelerated vascular aging in 75% of patients. To strengthen the concept of VA, further efforts are needed to better standardise the current approaches to estimate VA and, thereby, to improve comparability and clinical utility. KW - arterial stiffening KW - atherosclerosis KW - calcification KW - carotid artery disease Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-265810 VL - 11 IS - 1 ER - TY - JOUR A1 - Surat, Güzin A1 - Bernsen, Dominik A1 - Schimmer, Christoph T1 - Antimicrobial stewardship measures in cardiac surgery and its impact on surgical site infections JF - Journal of Cardiothoracic Surgery N2 - Objective The goal of this study was to monitor the compliance and impact on a protocol change of surgical antimicrobial prophylaxis in cardiac surgery favouring cefazolin instead cefuroxime, initiated by the hospital’s antimicrobial stewardship team. Methods This quality improvement study was performed in a tertiary care hospital in collaboration with the department of cardiothoracic surgery and the hospitals antimicrobial stewardship team following a revision of the standard for surgical antimicrobial prophylaxis including 1029 patients who underwent cardiac surgery. 582 patients receiving cefuroxime and 447 patients receiving cefazolin respectively were compared without altering any other preventative perioperative measures including its postoperative duration of less than 24 h. Adherence and surgical site infections were compiled and analysed. Results A complete adherence was achieved. Overall surgical site infections occurred in 37 (3.6%) of the cases, 20 (3.4%) in cefuroxime patients and 17 (3.8%) in cefazolin patients (p value = 0.754). No statistically significant differences could be found in any of the primary endpoints, but there was a trend towards less deep sternal wound infections in the cefazolin group. Conclusions The study supports the role of antimicrobial stewardship in cardiac surgery and mirrors the success of a multidisciplinary team aiming to minimize adverse events by optimizing antibiotic use. KW - antimicrobial stewardship KW - surgical antimicrobial prophylaxis KW - cardiac surgery KW - surgical site infections Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-265533 VL - 16 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 -