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ABSTRACT: Pseudoaneurysmen sind eine seltene Komplikation nach prothetischem Ersatz der Aorta ascendens und aorto-koronaren Bypass Operationen.
Wir stellen ein Fall vor, bei dem nach Ersatz der Aortenklappe, der Aorta ascendens und Anlage zweier venöser aorto-koronarer
Bypässe ein großes Pseudoaneurysma von einer der proximalen Bypass-Anastomosen ausging. Die präoperative Diagnose sowie die
Darstellung der epikardialen Koronargefäße wurde mittels Ultrafast-CT (Electron Beam Tomography, EBT) gesichert, da weder
das Pseudoaneurysma, noch der aus ihm hervorgehende venöse Bypass bei der Koronarangiographie selektiv darstellbar waren.
Pseudoaneurysms are a rare complication following replacement of the ascending aorta or aorto-coronary bypass surgery. We
report a case with replacement of the aorta ascendens, the aortic valve, and venous aorto-coronary bypass grafting, in whom
a pseudoaneurysm developed at the site of one proximal bypass anastomosis. For the preoperative diagnosis, an ultrafast-CT
(Electron Beam Tomography, EBT) was done, as neither the pseudoaneurysm, nor the venous graft could be visualized by selective
coronary angiography.
Schlüsselwörter Pseudoaneurysma – Bentall’sche Operation – Aorta ascendens Ersatz – Ultrafast-CTKey words Pseudoaneurysm – Bentall procedure – aorto ascendens replacement – ultrafast-CT
Zeitschrift für Kardiologie 04/2012; 89(3):195-198. · 0.97 Impact Factor
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ABSTRACT: Progression of coronary artery disease (CAD) after primary coronary artery bypass grafting (CABG) is frequent and may lead to recurrent symptoms. Various data indicate that apoptosis is the main event occurring during development and progression of atherosclerotic plaque. Plaque vascular smooth muscle cells (VSMCs) are more sensitive than regular VSMCs to TP53-mediated apoptosis.
We investigated EDTA blood of 192 patients (18% female, age 60.9 ± 7.4 years) who had primary CABG more than 5 years ago. CAD progression was defined as clinical endpoints: re-operation (n = 88; 46%), catheter re-intervention (n = 58; 30%), or angina at follow-up (n = 89; 46%). Apoptotic gene polymorphisms (Toll-like receptor 2 A753G, FAS ligand C-844T, FAS promoter G-670A, TP53 Arg72Pro, and CD14 C-260T) were investigated by PCR-RFLP and compared to healthy controls (n = 200, 24% female, age 63.4 ± 5.4). Gender-specific analysis was carried out.
Heterozygous, homozygous and wild-type expression of all five genetic polymorphisms showed almost identical distribution between patients with CAD and healthy controls. Looking at clinical endpoints, with GG expression of Toll-like receptor 2 polymorphism and GG expression of FAS promoter polymorphism, results showed a relative increased risk (p = 0.09) for recurrent symptoms and re-intervention. Patients with FAS promoter polymorphism with AA expression had an increased risk of suffering from recurrent symptoms (n = 28, p = 0.04). We found that patients with homozygous expression of TP53 polymorphisms (n = 3, all male) were prone to needing re-intervention after prior CABG (p = 0.03), but not re-operation. Over a period up to 15 years, the re-intervention rate was significantly different in homozygous genotypes of FAS LG, FAS promoter and TP53.
Patients presenting with polymorphisms of FAS LG, FAS promoter and TP53 have an increased risk of CAD progression, as they have a higher rate of re-interventions.
Agents and Actions 02/2011; 60(5):439-45. · 1.59 Impact Factor
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ABSTRACT: Polyclonal antithymocyte globulins (ATGs) are immunosuppressive agents applied for the treatment and prevention of organ rejection after transplantation. ATGs induce complement-mediated cell death in T lymphocytes and decrease leukocyte adhesion. However, little is known about the effects of ATGs on endothelial cells (EC). Our aim was to study the influence of ATGs upon the expression of adhesion molecules on human umbilical vein endothelial cells (HUVECs) after stimulation with tumor necrosis factor (TNF)-alpha.
HUVECs obtained from umbilical cords were incubated with ATGs before and after 6-hour stimulation with TNF-alpha. The group incubated without ATG served as the controls. Another group was not stimulated with TNF-alpha. By flow cytometry, we analyzed the expression of several adhesion molecules: intercellular adhesion molecule (ICAM)-1, vascular cell adhesion molecule (VCAM), platelet EC adhesion molecule (PECAM), and CD62E. Statistical analysis used analysis of variance.
After TNF-alpha stimulation, the EC surface expression of ICAM-1 and CD62E was reduced, although not significantly, in treated as compared with untreated cells. The expression of ICAM-1 and CD62E was similar in the unstimulated groups. The expression of VCAM, PECAM, CD55, and CD58 was not modified by ATG treatment.
Our results demonstrated that ATGs insignificantly reduced the expression of adhesion molecules in HUVECs. The effect of ATGs on stimulated HUVECs remains unclear, probably due to the lack of effector cells.
Transplantation Proceedings 06/2010; 42(5):1931-4. · 1.00 Impact Factor
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ABSTRACT: Xenograft survival is a balance between immunological rejection and adaptive changes in the graft. Immunohistochemical analysis of vascular immunoglobulin deposition in heterotopic and orthotopic pig to primate cardiac xenografts shows vascular antibody deposition as early as 30 min after reperfusion and throughout the transplant period in both GT+ and GTKO hearts. Despite the abundance of antibody, graft contractility in heterotopic transplants and the ability of the graft to support orthotopic recipients remained high, with little evidence of microvascular thrombosis for extended periods of time. This suggests that the graft is actively adapting to chronic antibody exposure to forestall thrombosis.To investigate the effects of chronic antibody exposure we used an Affymetrix porcine gene array to study the changes in gene expression in orthotopic transplant recipients. Four sets of mRNA were studied, Group 1: normal porcine hearts were used as controls (n = 2), Group 2: long surviving pig-to-primate orthotopic xenografts (n = 5), Group 3: orthotopic xenografts which failed in the perioperative period to support the recipient (n = 7) and Group 4: orthotopic xenografts that were rejected (n = 3). RNA from each group was used to produce cDNA for hybridization to an Affymetrix porcine gene array (?900624). This array contains 23 935 probes. We used a previously reported extended annotation database which provides annotations for 21 122 gene titles [1]. The raw fluorescence was normalized and each probe was subjected to a present/absent test using the Affymetrix MAS 5.0 algorithm. A Student's t-test was used to compare expression of each probe in the experimental groups (Groups 2–4) to Group 1 the control hearts. The DAVID Bioinformatics database [2] was used to identify enrichments in Kegg pathways and in Gene Ontogeny attributes.Orthotopic cardiac xenograft recipients survived for 14, 23, 34, 40 and 57 days without rejection. Recipients died due to sudden death for unknown cause, atrial hemorrhage, pulmonary hemorrhage, pneumonitis and sepsis respectively. Histologic analysis of these hearts at necropsy showed minimal injury (10%) in three recipients and moderate damage (35–45%) in two recipients. In no instance was death due to heart failure. Group 3 hearts failed within 48 hours of transplant. These hearts initially exhibited good cardiac function, based on echocardiography but could not maintain that function as they were weaned from inotropic support. Histology of the failed hearts showed vascular antibody deposition but only rarely was complement deposition (C5b) detected. There was moderate ischemic injury to the myocardium but little evidence of hemorrhage. In no instance was heart failure due to hyperacute rejection. The rejected orthotopic xenografts failed on days 9, 14 and 25. Histology showed widespread vascular antibody staining and complement deposition.Real time PCR validation of the gene array data was performed with 58 probes using RNA from the long surviving xenograft (Group 2). There was greater than 90% correlation. Groups 2–4 showed a similar number of probes which passed the exclusion test (16 006 Group 2, 16 991 Group 3 and 16 214 Group 4), however, rejected hearts (Group 4) showed the fewest number of probes with significant deviation from the control samples. Genes with highly altered levels of expression (more that 3 standard deviations from the controls) were variably regulated between Groups 2–4. For example, long surviving orthotopic hearts (Group 2) exhibited an equal proportion of genes with highly increased or decreased expression. In rejected hearts (Group 4) genes with highly altered expression were overwhelming due to decreased gene expression. All experimental groups showed increased expression of genes commonly associated with myocardial injury.Bioinformatics analysis detected enrichment in genes involved in KEGG pathways for focal adhesion, extracellular matrix receptor interactions and cell communication in the long surviving orthotopic hearts (Group 2). Additionally there was enrichment in several metabolic pathways. The changes in metabolic gene expression were also evident, to lesser degree, in the rejected hearts but not observed in hearts which failed during the perioperative period (Group 3). These results suggest that long surviving orthotopic cardiac xenografts maybe undergo extracellular remodeling and have altered metabolic activity. This analysis suggests that chronic antibody exposure may effect endothelial cell functions beyond haemostasis which promote cardiac remodeling and altered metabolism and may contribute to graft failure.This work was supported by NIH grant #U01 AI066310References1. Tsai S, Cassady JP, Freking BA, Nonneman DJ, Rohrer GA, Piedrahita JA. Annotation of the affymetrix porcine genome microarray. Anim Genet2006; 37(4): 423–424.2. Huang DW, Sherman BT, Lempicki RA. Systematic and integrative analysis of largegene lists using DAVID bioinformatics resources. Nature Protoc. 2009; 4(1): 44–57.
Xenotransplantation 04/2010; 17(2):115 - 116. · 2.33 Impact Factor
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ABSTRACT: The purpose of this study was to evaluate the effect of both spraying pump capacity (PCp) and initial polyurethane concentration
(PUic) in chloroform-polyurethane blend solution on the cell colonization efficiency of polyurethane (PU) scaffolds produced
by the spraying technique. This technique will be used for tissue engineering of aortic valves. Patches (n=14), sprayed with
different PCp and PUic, were seeded with human vascular fibroblasts FBs and endothelial cells ECs and evaluated by using scanning
electron microscopy (SEM) and immunohistochemical staining (IHC). FBs and ECs colonization efficiency on PU-patches can be
improved by increasing the PUic in the blend solution. PCp does not appear to be relevant for the seeding efficiency.
01/2010: pages 5-6;
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ABSTRACT: The aim of this study was to evaluate cell adhesion and pro-inflammatory cytokine expression of human vascular cells seeded
on polyurethane grafts (PUG) under physiological conditions in a newly developed closed perfusion system. Human vascular fibroblasts
(FBs) and endothelial cells (ECs) were isolated from saphenous vein segments and expanded in culture. PUG (n= 17, A= 38 ±
3 cm2) were either seeded with ECs (n= 9) or pre-seeded with FBs (n= 8), followed by colonization with ECs. Seeded PUGs were then
divided into four groups and exposed for 4 hours to variable flow conditions. Samples were taken before and after perfusion
and evaluated by scanning electron microscopy (SEM) and reverse transcriptionpolymerase chain reaction (RT-PCR) for the expression
of the cytokines interleukin 1-alpha (IL-1a), interleukin 6 (IL-6), interleukin 8 (IL-8) and monocyte chemoattractant protein-1
(MCP-1). Conditioning of colonized vascular cells in a pulsatile Bioreactor significantly decreases pro-inflammatory cytokine
expression. Pre-seeding with FBs enhance the adhesion of ECs to PUG. Microbiological tests of perfusion medium after 4 hours
perfusion revealed no bacterial contamination. Bioreactors with pulsatile flow can be used for an in-vitro conditioning of
tissue-engineered cardiovascular prostheses.
01/2010: pages 7-8;
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ABSTRACT: The purpose of this study was to examine the hemodynamic performance of a new polyurethane scaffold for aortic valve tissue
engineering. A new experiment set-up was developed to simulate blood flow in the aortic position and to visualize the flow
field along valve scaffolds. Aortic valve scaffolds (n= 6) were sprayed with different cusps thickness (dCusps): Group A (n= 2, dCusps= standard), Group B (n= 4, dCusps= double) and evaluated by means of time resolved 2D particle image velocimetry (PIV). The results of the flow measurements
showed similar hemodynamic performance of both groups. Valve scaffolds open and close properly and show no or minimal backflow
through the valve during diastole.
12/2009: pages 831-832;
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The Thoracic and Cardiovascular Surgeon 09/2009; 57(5):251-6. · 0.88 Impact Factor
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ABSTRACT: This prospective study investigates the impact of proton pump inhibitors (PPI) on mycophenolic acid (MPA) pharmacokinetics in heart transplant recipients receiving mycophenolate mofetil (MMF) and tacrolimus. MPA plasma concentrations at baseline (C(0 h)), 30 min (C(0.5 h)), 1(C(1 h)) and 2 h (C(2 h)) were obtained by high-performance liquid chromatography (HPLC) in 22 patients treated with pantoprazole 40 mg and MMF 2000 mg. Measurements were repeated 1 month after pantoprazole withdrawal. A four-point limited-sampling strategy was applied to calculate the MPA area under the curve (MPA-AUC). Predose MPA concentrations with PPI were 2.6 +/- 1.6 mg/L versus 3.4 +/- 2.7 mg/L without PPI (p = ns). Postdose MPA concentrations were lower with PPI at C(0.5 h) (8.3 +/- 5.7 mg/L vs. 18.3 +/- 11.3 mg/L, p = 0.001) and C(1 h) (10.0 +/- 5.6 mg/L vs. 15.8 +/- 8.4 mg/L, p = 0.004), without significant differences at C(2 h) (8.3 +/- 6.5 mg/L vs. 7.6 +/- 3.9 mg/L). The MPA-AUC was significantly lower with PPI medication (51.2 +/- 26.6 mg x h/L vs. 68.7 +/- 30.3 mg x h/L; p = 0.003). The maximum concentration of MPA (MPA-C(max)) was lower (12.2 +/- 7.5 mg/L vs. 20.6 +/- 9.3 mg/L; p = 0.001) and the time to reach MPA-C(max) (t(max)) was longer with PPI (60.0 +/- 27.8 min vs. 46.4 +/- 22.2 min; p = 0.05). This is the first study to document an important drug interaction between a widely used immunosuppressive agent and a class of drugs frequently used in transplant patients. This interaction results in a decreased MMF drug exposure which may lead to patients having a higher risk for acute rejection and transplant vasculopathy.
American Journal of Transplantation 07/2009; 9(7):1650-6. · 6.39 Impact Factor
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ABSTRACT: Paravalvular fistulas may complicate the clinical course after heart valve surgery. Medical treatment may be ineffective, repeated surgical revisions may be associated with increased morbidity and mortality.
After valve sparing surgery in bicuspid aortic valve, a significant aorto-left atrial fistula was diagnosed in a 72-year-old patient causing heart failure and catecholamine-dependency. Due to the critical hemodynamic state, percutaneous closure was performed with an AGA Amplatzer duct occluder. Secondary to this closure, a second fistula between the aortic root and the right atrium appeared which was closed during the same procedure implanting a second duct occluder beneath the first device.
Percutaneous closure of paravalvular fistulas is feasible and a safe method for the treatment of significant shunts after valve surgery. Even in multiple fistulas, the implantation of small devices allows for a focussed interventional closure of such leaks. This procedure should be considered for such defects as it represents a safe method for the causative treatment in paravalvular lesions after valve surgery especially in patients with critical hemodynamic conditions.
Clinical Research in Cardiology 05/2009; 98(7):451-4. · 2.95 Impact Factor
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ABSTRACT: We developed a new fabrication technique for 3-dimensional scaffolds for tissue engineering of human heart valve tissue. A human aortic homograft was scanned with an X-ray computer tomograph. The data derived from the X-ray computed tomogram were processed by a computer-aided design program to reconstruct a human heart valve 3-dimensionally. Based on this stereolithographic model, a silicone valve model resembling a human aortic valve was generated. By taking advantage of the thermoplastic properties of polyglycolic acid as scaffold material, we molded a 3-dimensional scaffold for tissue engineering of human heart valves. The valve scaffold showed a deviation of only +/-3-4% in height, length and inner diameter compared with the homograft. The newly developed technique allows fabricating custom-made, patient-specific polymeric cardiovascular scaffolds for tissue engineering without requiring any suture materials.
European Surgical Research 12/2008; 42(1):49-53. · 0.93 Impact Factor
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ABSTRACT: Polyclonal anti-thymocyte globulins (ATGs) are immunosuppressive agents used for the treatment and prevention of acute organ rejection after transplantation. ATGs induce apoptosis and complement-mediated cell death in peripheral T-lymphocytes and have shown a reduction of leukocyte adhesion after ischemia-reperfusion (IRI). We analyzed the impact of different ATGs upon the expression of adhesion and inflammation molecules after IRI.
The major arteries and veins of the extremities of cynomolgus monkeys were surgically isolated and flushed with Ringer's lactate at 4 degrees C. After 60 min of ischemia the limbs were reperfused with matching human blood. ATGs were added to the blood 30 min prior to the reperfusion, forming four groups: Tecelac-ATG group (n=16), Fresenius(S)-ATG group (n=16), Thymoglobulin-ATG group (n=12) and a control group (n=16). Biopsies from muscular tissue were obtained after the experiments. The expression of adhesion (ICAM-1, VCAM, PECAM, CD11b, CD62E) and inflammation (IL-1, IL-6, TNF-alpha) molecules on endothelium, leukocytes, and reperfused tissue was analyzed by means of immunohistochemistry.
The expression of the studied adhesion molecules (ICAM-1, VCAM, PECAM, CD11b, and CD62E) was significantly increased in the control group when compared with the treated groups. The expression of IL-1, IL-6, and TNF-alpha was reduced in the ATG-groups in comparison to the control group.
Our results showed that ATGs caused a reduction of the expression of adhesion and inflammation molecules both in endothelium and reperfused tissue. The inhibition of the expression of molecules required for firm cellular adhesion, may contribute to decreasing cellular graft infiltration after post-ischemic reperfusion.
Transplant Immunology 12/2008; 20(4):224-8. · 1.46 Impact Factor
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The Journal of thoracic and cardiovascular surgery 10/2008; 136(3):792-3. · 3.41 Impact Factor
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ABSTRACT: Today, organ transplantation represents a well-established and effective therapy of terminal organ failure revealing high actuarial survival rates. Unfortunately, the enormous potential of organ transplantation cannot be tapped due to the significant gap between organ demand and organ donation. Current statistics of the International Society of Heart and Lung Transplantation prove a continuity of depressed numbers of transplantations performed per year since the late nineties. To counteract the persisting severe shortage of human organs in Germany and worldwide suboptimal donor organs and/or organs from older donors were accepted. Both the acceptance of inferior organs and the implementation of the Transplantation Law (in Germany in 1997) could not answer this problem. Increasing the donor rates emerge difficult to achieve and will ultimately result in numbers which are not sufficient. The improvement of transplant results by e.g. a less nephrotoxic immunosuppression, or the generating of hyporeactivity or even tolerance is an additional aim important to achieve. Alternative techniques to answer the tremendous organ shortage might be the differentiation of embryonic stem cells or the reprogramming of adult stem cells as a virtually unlimited source for cell replacement to treat degenerative diseases or traumatic tissue injury. Yet, disadvantages such as ethical issues and the generation of tumorigenic cells should not be underestimated. A cellular therapy by the injection of undifferentiated bone marrow (CD133(+) stem/progenitor) cells into the myocardium in combination with or without aortocoronary surgery for chronic ischemic heart disease as well as cells from the amniotic fluid (Wharton's jelly) might also represent possible future solutions to the organ deficit but still are far from a functional substitution of the human heart. Until now there is no in-all implantable mechanical heart assist device which is able to completely and permanently replace the human organ and provide a quality of life comparable to that after allotransplantation. In contrast, xenotransplantation, using porcine organs for human transplantation, offers a potential solution to the world-wide lack of donor organs. The advantages of xenotransplantation are an unlimited disposability of donor organs, an elective transplantation with a subsequent reduction of ischemic time and the possibility of a pre-operative start of the immunosuppressive therapy of the recipient. Harmful effects of the brain death of the donor to the donor organ could be excluded. Finally, genetic modifications of compatible xenografts could be made. Substantial progress of the research in the field of xenotransplantation has been possible thanks to the introduction of organs from genetically engineered pigs transgenic for human complement regulatory proteins [e.g. human decay accelerating factor (hDAF/hCD55), human membrane cofactor (hMCP/hCD46), and human membrane inhibitor of reactive lysis (hMIRL/hCD59)]. Using an effective and persistent depletion of preformed cytotoxic anti-Galalpha(1,3)Gal antibodies (IgM and IgG) by a Galalpha(1,3)Gal therapeutic (e.g. GAS914, TPC) in combination with these transgenic pigs hyperacute rejection can be avoided successfully. During the early phase after transplant acute vascular rejection triggered by induced anti-Galalpha(1,3)Gal antibodies can be controlled. Several groups developed pigs which lack the Galalpha(1,3)Gal xenoantigen. Studies on xenotransplantations performed with homozygous alpha(1,3)-galactosyltransferase gene knockout pigs demonstrated that these modified pig organs offer some progress in terms of graft survival. Thus, the major xenoantigen Galalpha(1,3)Gal is no longer an unsurmountable immunological barrier preventing transplantation of pig organs into humans. Acute vascular rejection, however, remains as a major hurdle to clinical application of xenotransplantation due to cytotoxic anti-pig antibodies of other specificity than Galalpha(1,3)Gal. Furthermore, humoral factors are not the only players in xenograft rejection. Primate anti-pig cellular immunity is defined by multifocal lymphocytic infiltrates, with morphologic evidence of direct tissue damage. Pre-requisites for the clinical use of xenotransplantation are PERV-C (porcine endogenous virus C) free animals using a PERV knock down (si-RNA) technique. Multitransgenic alphaGalT-KO [alpha(1,3)-galactosyltransferase knockout] pigs additionally expressing human complement regulator proteins, and human anticoagulants (e.g. human thrombomodulin) are necessary to reliably prevent not only hyperacute rejection as the first immunological barrier, but also acute vascular rejection at its beginning, when serum cytotoxicity to the pig heart appears to be predominantly Galalpha(1,3)Gal-specific. Further co-stimulation blockade (e.g. PD-1L, CTLA-4-Ig), HLA-E [protection against human NK (natural killer)-cells], or haemeoxygenase-1 (defense against disseminated intravascular coagulation) will help to suppress acute vascular and acute cellular xenograft rejection. Special pathogen free (SPF) units and breeding conditions of pig organ donors limit the risk of microbial contamination by most pathogens liable to be transmitted from a pig graft to a human recipient. Our DFG-(German Research Council) Transregio Research Group Xenotransplantation assembles an interdisciplinary group of leading German laboratories incl. biotechnologists, immunologists, virologists, and surgeons with vast experimental expertises in the field of experimental and clinical allotransplantation and experimental xenotransplantation. The first clinical goal of xenotransplantation is xenogeneic tissue transplantation such as the transplantation of porcine islet cells (alphaGalT-KO (?), CTLA-4-Ig expression) in diabetic patients with hypoglycemic attacks as well as porcine cornea, porcine cardiomyocytes and porcine heart valves, possibly porcine bones and teeth (?). Thereafter, xenogeneic organ transplantation starting with the more promising use of kidneys and hearts is the definitive clinical goal. In summary, clinical heart transplantation represents an accepted method of end-stage heart failure with an outdated "standard immunosuppression" and the need of an individualized immunosuppression adjusted to the specific needs of the individual patient. The organ shortage remains the main obstacle of the heart transplantation, and other organ transplantation, respectively. In the near future, xenotransplantation will be possible!
Xenotransplantation 10/2008; 15(5):293-294. · 2.33 Impact Factor
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ABSTRACT: To prospectively evaluate whether planimetric measurements of aortic valve area (AVA) with dual-source computed tomography (DSCT) correlate with measurements obtained by echocardiography and to correlate the amount of calcification of the aortic valve with AVA in a group of patients after aortic valve replacement.
23 patients underwent dual-source computed tomography (DSCT) of the heart (Somatom Definition, Siemens Medical Solutions, Forchheim, Germany), without heart rate control (heart rate 52-113 beats/minute). All patients had undergone aortic valve replacement (homografts, mean time after surgery: 7+/-3 years). The AVA of the transplanted aortic valve graft was measured planimetrically by means of DSCT and compared with echocardiography as a standard of reference, to exclude post-surgical restenosis of the valve. Maximum AVA in systole planimetrically measured with CT was compared with calculated AVA values determined with the continuity equation, using transvalvular pressure gradients. The amount of calcification of the aortic valve was quantified and correlated (Spearman's R) with the AVA. To assess intra- and inter-reader reproducibility, the DCST data was re-analyzed by two readers 4 weeks after the initial review.
All DSCT datasets were of diagnostic image quality concerning valve depiction. The mean AVA as measured by DSCT was 2.7+/-0.9 cm (2) compared to 1.8+/-0.5 cm (2) by echocardiography (p<0.05). The planimetric evaluation of the CT data as compared to results of echocardiography showed a significant correlation of the results (Pearson's correlation coefficient R=0.78, p<0.001). Intra- and inter-reader reproducibility was good with intra-class correlation coefficients of 0.86 and 0.81, respectively (p<0.001). There was a significant negative correlation between the amount of aortic valve calcification and AVA as measured by echocardiography (R= -0.42; p<0.05) and as measured by DSCT (R= -0.67; p=0.001).
First experience indicates that DSCT is able to assess aortic valve opening area with high image quality and good intra- and inter-reader reproducibility in subjects after aortic valve replacement. The negative correlation between AVA and the amount of aortic valve calcification suggests that calcification is a possible risk factor for restenosis in subjects with aortic valve replacement.
RöFo - Fortschritte auf dem Gebiet der R 06/2008; 180(6):553-60. · 2.76 Impact Factor
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ABSTRACT: Primary organ failure after heart transplantation is a severe complication generally related to prolonged ischemia time, poor quality of the organ, or rejection. Ca(2+) sensitisers increase cardiac contractility without altering intracellular Ca(2+) levels. Our aim was to evaluate the influence of levosimendan in the therapy of primary failure after heart transplantation. Five patients presenting with reduced ejection fraction (EF<30%) and high dosed catecholamines after heart transplantation were treated with levosimendan (Simdax, Abbot GesmbH, Vienna, Austria) in a 24-hour continuous infusion (0.10 microg/kg*min) postoperatively. We assessed hemodynamic measurements including MAP, CVP, and PAP as well as heart function. Pharmacologic support with catecholamines could be halved at 24 hours and terminated in four of the patients 72 hours after levosimendan administration. Hemodynamics (MAP 70 +/- 11 vs 85 +/- 6 mm Hg; CI 2.5 +/- 0.4 vs 3.6 +/- 0.4 L/min/m(2)) and EF (28 +/- 10 vs 54 +/- 4%) improved at 48 hours after treatment. Acute graft failure after cardiac transplantation is associated with poor short- and long-term outcomes. Among our patients, levosimendan reduced the need for catecholamine support as well as improved ventricular performance.
Transplantation Proceedings 05/2008; 40(4):951-2. · 1.00 Impact Factor
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ABSTRACT: Delayed perforation of a passive fixed pacemaker lead is a rare complication after pacemaker implantation and is associated with increased morbidity and mortality. We report the case of an 82-year-old patient who presented with a delayed perforation of the right heart wall, the pericardium, and the chest wall by a passive-fixation ventricular lead 14 months after pacemaker implantation. The lead was uneventfully extracted transvenously and repositioned in the right ventricle with good pacing and sensing.
Heart Surgery Forum 02/2008; 11(3):E137-9. · 0.63 Impact Factor
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ABSTRACT: Anomalous origin of the left coronary artery from the pulmonary artery (ALCAPA) is a rare congenital defect. This anomaly leads to a coronary hypoperfusion phenomenon and to substantial left ventricular dysfunction caused by abnormal perfusion of the left ventricle. The optimal surgical management of such cases is not clearly established. Here, we report the successful anatomic repair of ALCAPA arising from the non-facing sinus of Valsalva of the pulmonary artery in a 5-kg patient. In order to perform the repair, we created an autologous extrapulmonary tunnel (from a pulmonary artery flap and autologous pericardium), which we implanted into the ascending aorta. Because of postcardiotomy heart failure, we implanted an extracorporeal membrane oxygenation device during the same procedure. After recovery of the failing heart, the device was easily explanted, and the patient was discharged from the hospital on postoperative day 30. [ABSTRACT FROM AUTHOR]
Copyright of Texas Heart Institute Journal is the property of Texas Heart Institute and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts)
Texas Heart Insitute Journal. 01/2008; 35:32-35.
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The Thoracic and Cardiovascular Surgeon. 01/2008;
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M A Deutsch,
I Kaczmarek,
S Huber,
D Schmauss,
A Beiras-Fernandez,
M Schmoeckel,
R Ochsenkuehn,
B Meiser,
J Mueller-Hoecker,
B Reichart, B Bruno Reichart
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ABSTRACT: The mammalian-target-of-rapamycin/mTOR-inhibitor sirolimus as a component of the immunosuppressive strategy after solid organ transplantation is effective at preventing allograft rejection. However, recent reports indicate that sirolimus is associated with altered sex hormone levels and impaired sperm quality parameters. Herein, we report on a case of sirolimus-associated infertility in a young male heart-lung transplant recipient and provide a detailed synopsis of potential mechanisms by which sirolimus may negatively influence spermatogenesis. Testicular immunohistochemistry, the course of sex hormone and sperm quality parameters of our patient support the hypothesis that mTOR might act as an important key regulator in the reproductive system. Fortunately, due to withdrawal of sirolimus as part of the maintenance, immunosuppression improved sperm quality and sex hormone parameters could be observed. Recently, these improvements even resulted in a spontaneous pregnancy of the patient's wife more than 1 year after the drug was withdrawn. In our view, oligospermia as a possible and at least partly reversible side-effect of mTOR inhibitors has to be taken into consideration, particularly, when administrated to young male patients.
American Journal of Transplantation 11/2007; 7(10):2414-21. · 6.39 Impact Factor
