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Featured researches published by K. Alexiou.


The Annals of Thoracic Surgery | 2013

Transapical Transcatheter Valve-in-Valve Implantation for Deteriorated Mitral Valve Bioprostheses

Manuel Wilbring; K. Alexiou; Sems Malte Tugtekin; Bjoern Sill; Peter E. Hammer; Torsten Schmidt; Gregor Simonis; Klaus Matschke; Utz Kappert

BACKGROUND The transcatheter valve-in-valve concept has been described for patients requiring redo valve surgery. We report our experience with transapical mitral valve-in-valve implantation. METHODS Since 2008, 301 patients were treated with transapical transcatheter valve implantation. Seven of these patients presented with a deteriorated mitral valve bioprosthesis and underwent transapical mitral valve-in-valve implantation. Median age was 79 years. Preoperatively, all patients presented in New York Heart Association functional class III. For risk estimation, The Society of Thoracic Surgeons and European System for Cardiac Operative Risk scores were used and predicted high mortality (mean ± standard error of mean: Society of Thoracic Surgeons mortality, 12.3% ± 2.1%; European System for Cardiac Operative Risk mortality, 58.0% ± 7.0%). Mean follow-up time was 93 ± 29 days, with a total of 21.6 patient-months. RESULTS Preoperatively, all patients who had deteriorated bioprostheses presented with severe regurgitation and increased transvalvular pressure gradients (maximal pressure gradient, 23.9 ± 0.9 mm Hg; mean pressure gradient, 11.3 ± 1.0 mm Hg). One patient was identified with mitral valve stenosis (effective orifice area, 0.25 cm(2)). All patients underwent successful transapical mitral valve-in-valve implantation. Sizes of previously implanted bioprostheses were 27, 29, and 31 mm; Edwards SAPIEN valves at sizes 26 and 29 mm were implanted. Postoperatively, echocardiography revealed excellent hemodynamics with no remaining mitral regurgitation in 5 patients and minimal regurgitation in 2 patients. Transvalvular pressure gradients decreased significantly (maximal pressure gradient, 13.8 ± 2.1 mm Hg; mean pressure gradient 5.7 ± 0.8 mm Hg, p < 0.05). One patient had fatal pneumonia on postoperative day 34. No patient died during further follow-up, and all patients remained in New York Heart Association class I or II. CONCLUSIONS Our results demonstrate the feasibility of transapical mitral valve-in-valve implantation for treatment of a degenerated bioprosthesis (size range, 27 to 31 mm) using the Edwards SAPIEN valve in sizes 26 and 29 mm.


Transplant International | 2005

Protection against acute porcine lung ischemia/reperfusion injury by systemic preconditioning via hind limb ischemia

Thomas Waldow; K. Alexiou; Wolfgang Witt; Steffen Albrecht; Florian Wagner; Michael Knaut; Klaus Matschke

Previous work on various organs and tissues has shown that ischemic preconditioning protects against reperfusion injury in these organs and also against secondary effects in the lung. In contrast, the purpose of this study was to investigate the effects of preconditioning in a remote organ (hind limb ischemia) on an ischemia/reperfusion (I/R) treatment of the lung itself. A porcine model of in situ left lung ischemia (90 min) and reperfusion (5 h) was used. Systemic preconditioning was induced by clamping the left common femoral artery (3 × 5 min). Lung injury was assessed in terms of pulmonary vascular resistance, pulmonary artery pressure, pulmonary venous and arterial pO2, and tissue macrophage counts. The zymosan‐stimulated release of reactive oxygen species (ROS) in whole blood was determined by a chemiluminometric procedure. Inflammatory cytokines (interleukin‐1β and interleukin‐6) were measured in arterial plasma as indicators of a systemic inflammatory reaction. Preconditioning by hind limb ischemia completely prevented the I/R‐induced functional impairment of the lung, the pulmonary hypertension and the reduced oxygenation capacity. The plasma levels of interleukin‐1β and the macrophage counts in preconditioned animals were reduced to control values, whereas the levels of interleukin‐6 and the release of ROS were not affected by preconditioning. In conclusion, systemic preconditioning by repeated hind limb ischemia protects against acute I/R injury of the lung but not against all indices of reperfusion‐associated systemic inflammation.


Thoracic and Cardiovascular Surgeon | 2009

Midterm follow-up of patients with perioperative myocardial infarction after coronary artery bypass surgery: clinical significance of different treatment strategies.

K. Alexiou; Manuel Wilbring; Christian Koch; Utz Kappert; Sems Malte Tugtekin; Klaus Matschke

BACKGROUND The purpose of the study was to analyze the causes of postoperative myocardial infarction (PMI) and the impact of different treatment strategies on (1) postoperative outcome, (2) major adverse events (MACE), and (3) postoperative Canadian Cardiovascular Society (CCS) at 3-year follow-up. PATIENTS Between May 2001 and July 2006, 113 patients with PMI were categorized in three groups: (A) conservative therapy (50 patients); (B) percutaneous coronary intervention (PCI) (25 patients), and (C) re-CABG (38 patients). RESULTS Overall in-hospital mortality was 7.1% (n = 8), being 10.0% in group A (n = 5), 4.0% in group B (n = 1) and 5.3% (n = 2) in group C (p = n.s.), respectively. The cumulative survival rates at 3 years were 90% for group A, 92% for group B, and 89.5% for group C (p = n.s). The MACE rate at 3-year follow-up for all patients was 27.4% and was significantly higher in group A (34%) and group B (36%) compared with group C (13.2%) (p = 0.05). Mean CCS was significantly reduced at follow-up in the groups compared with the preoperative angina class. However, group B and C showed a significant improvement in CCS compared with group A (p = 0.044/p < 0.001). Further group C was superior to group B (p = 0.032). CONCLUSION At 3 years of follow-up, this study showed no survival benefits from any therapeutical procedure; however patients treated with re-CABG had better freedom from repeat revascularization procedures and from MACCE. In addition, the conservative and PCI group had a higher incidence of recurrence of angina.


Asian Cardiovascular and Thoracic Annals | 2007

Malplacement of a Pacemaker Lead — A Rare Cause for Aortic Valve Endocarditis

Klaus Matschke; Sm Tugtekin; K. Alexiou; M Knaut; Jw Park; M Schulze

Infective endocarditis of native valves following pacemaker implantation is rare but can be associated with serious complications, approaching a mortality of up to 25%. 1 Recent publications report a frequency of pacemaker related endocarditis between 0.5 and 7%. 2 Due to anatomical reasons the tricuspid valve is mostly affected in these patients, with involvement of the left heart valves usually secondary. We report an incidence of native aortic valve endocarditis due to a misplaced pacemaker lead into the left heart.


Asian Cardiovascular and Thoracic Annals | 2018

Cut-down outperforms complete percutaneous transcatheter valve implantation:

Markus Mach; Manuel Wilbring; Bernhard Winkler; K. Alexiou; Utz Kappert; Georg Delle-Karth; Martin Grabenwoger; Klaus Matschke

Background The ideal approach for transfemoral transcatheter aortic valve implantation is still widely debated. The objective of this study was to compare access and bleeding complications of complete percutaneous versus the surgical cut-down approach for transfemoral transcatheter aortic valve implantation. Methods The study included 667 consecutive patients from November 2008 to December 2016, 466 in the percutaneous group and 201 in the cut-down group. There were no significant differences in baseline characteristics between the 2 groups. Primary study endpoints were vascular access site and bleeding complications according to the Valve Academic Research Consortium II criteria. Results Mean procedure time was shorter in the cut-down group: 93.5 ± 22.0 (percutaneous) vs. 69 ± 19 min (cut-down), p < 0.001. The rate of access complications was higher in the percutaneous group: 20.4% (95/466) vs. 8.5% (17/201), p = 0.037; with predominantly minor complications in the percutaneous cohort: 14.4% (67/466) vs. 2.5% (5/201), p = 0.04. Bleeding complications were more frequent in the percutaneous group: 21.9% (102/466) vs. 4.5% (9/201), p = 0.01. Hospital mortality was 5.2% in the percutaneous group and 1.9% in the cut-down group (p = 0.075). Conclusions Surgical cut-down provided controlled access and resulted in fewer access site and bleeding complications. Nonetheless, major access complications were not significantly different between the two cohorts. The two approaches must be seen as complementary techniques. A portfolio containing both techniques is the only way to provide a tailor-made and patient-orientated approach ensuring the safest access based on the individual vessel condition.


Texas Heart Institute Journal | 2006

Entrapped Coronary Catheter Remnants and Stents: Must They Be Surgically Removed?

K. Alexiou; Utz Kappert; Michael Knaut; Klaus Matschke; Sems Malte Tugtekin


Pulmonary Pharmacology & Therapeutics | 2008

Preconditioning by inhaled nitric oxide prevents hyperoxic and ischemia/reperfusion injury in rat lungs

Thomas Waldow; Wolfgang Witt; André Ulmer; Andreas Janke; K. Alexiou; Klaus Matschke


Nitric Oxide | 2004

Protection of lung tissue against ischemia/reperfusion injury by preconditioning with inhaled nitric oxide in an in situ pig model of normothermic pulmonary ischemia

Thomas Waldow; K. Alexiou; Wolfgang Witt; Florian Wagner; Utz Kappert; Michael Knaut; Klaus Matschke


Thoracic and Cardiovascular Surgeon | 2007

Coronary artery bypass grafting in octogenarians--outcome with and without extracorporeal circulation.

Sm Tugtekin; Utz Kappert; K. Alexiou; Manuel Wilbring; Nagpal Ad; Klaus Matschke


Chest | 2004

Attenuation of reperfusion-induced systemic inflammation by preconditioning with nitric oxide in an in situ porcine model of normothermic lung ischemia.

Thomas Waldow; K. Alexiou; Wolfgang Witt; Florian Wagner; Vassilios Gulielmos; Klaus Matschke; Michael Knaut

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Klaus Matschke

Dresden University of Technology

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Utz Kappert

Dresden University of Technology

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Manuel Wilbring

Dresden University of Technology

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Sm Tugtekin

Dresden University of Technology

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Michael Knaut

Dresden University of Technology

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Sems Malte Tugtekin

Cardiovascular Institute of the South

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Klaus Matschke

Dresden University of Technology

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Michael Knaut

Dresden University of Technology

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Thomas Waldow

Cardiovascular Institute of the South

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