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Intracardiac Echocardiography during Catheter-Based Ablation of Atrial Fibrillation
Jürgen Biermann,Christoph Bode,Stefan Asbach
Cardiology Research and Practice , 2012, DOI: 10.1155/2012/921746
Abstract: Accurate delineation of the variable left atrial anatomy is of utmost importance during anatomically based ablation procedures for atrial fibrillation targeting the pulmonary veins and possibly other structures of the atria. Intracardiac echocardiography allows real-time visualisation of the left atrium and adjacent structures and thus facilitates precise guidance of catheter-based ablation of atrial fibrillation. In patients with abnormal anatomy of the atria and/or the interatrial septum, intracardiac ultrasound might be especially valuable to guide transseptal access. Software algorithms like CARTOSound (Biosense Webster, Diamond Bar, USA) offer the opportunity to reconstruct multiple two-dimensional ultrasound fans generated by intracardiac echocardiography to a three-dimensional object which can be merged to a computed tomography or magnetic resonance imaging reconstruction of the left atrium. Intracardiac ultrasound reduces dwell time of catheters in the left atrium, fluoroscopy, and procedural time and is invaluable concerning early identification of potential adverse events. The application of intracardiac echocardiography has the great capability to improve success rates of catheter-based ablation procedures. 1. Introduction Atrial fibrillation (AF) is the most prevalent sustained cardiac arrhythmia. Catheter-based ablation of AF is usually recommended for patients with symptomatic paroxysmal AF that is resistant to antiarrhythmic drug therapy. This approach is supported by results of randomized and prospective trials comparing antiarrhythmic drug treatment with catheter-based ablation, showing significantly better rhythm control after ablation. In addition, meta-analyses of studies performed mostly in patients with paroxysmal AF, comparing antiarrhythmic drugs and catheter-based ablation, have also clearly supported these findings [1–5]. As catheter-based ablation with electrical isolation of the pulmonary veins (PVs) has become an established therapeutic option for patients with symptomatic AF, accurate recognition of the complex and variable anatomy of the left atrium (LA) is indispensable. Circumferential PV isolation is generally guided by three-dimensional (3D) electroanatomical mapping [6–8], fluoroscopy [9], and/or intracardiac echocardiography (ICE) [10, 11]. However, only ICE offers the unique ability to image the LA in real time during the course of the procedure and to identify all structures which are important for the ablation. Endpoints for a circumferential PV isolation procedure are either amplitude reduction within the ablated
Successful Therapy of Ventricular Rupture by Percutaneous Intrapericardial Instillation of Fibrin Glue: A Case Report
Florian Willecke,Christoph Bode,Andreas Zirlik
Case Reports in Vascular Medicine , 2013, DOI: 10.1155/2013/412341
Abstract: Rupture of the ventricular myocardium is an often lethal complication after myocardial infarction. Due to the dramatic hemodynamics and the short time frame between ventricular rupture and surgical closure of the defect, additional therapeutic strategies are needed. Here we report the successful therapy of ventricular rupture by percutaneous intrapericardial instillation of fibrin glue in a 72-year-old male patient with postinfarct angina secondary to anterior myocardial infarction. 1. Case Report Rupture of the ventricular myocardium after myocardial infarction is a dramatic and often lethal complication. Due to the dramatic hemodynamic dysfunction, immediate therapies are imperative. As surgical repair of the defect is often not available, percutaneous intrapericardial instillation of fibrin glue can be an alternative. A 72-year-old male patient with postinfarct angina secondary to anterior myocardial infarction was transferred to our center from a community hospital after administration of systemic thrombolytic therapy using streptokinase. Coronary angiography showed single vessel disease with high grade stenosis of the LAD. Stent implantation was successfully performed with uncomplicated postinterventional course. On day three, the patient developed another episode of angina. Recatheterization excluded acute restenosis or stent thrombosis. On the same day, the patient developed rapid onset cardiogenic shock with need for resuscitation, intubation, high dose catecholamine treatment, and an intra-aortic balloon pump. Echocardiography showed an acute pericardial tamponade suggesting a ventricular rupture (Figure 1(a)). Pericardiocentesis was performed, and large amounts of blood could be aspirated and were directly retransfused. Hemodynamics stabilised only under constant aspiration. As ultima ratio, we instillated a total of 30?mL of a two-component fibrin glue normally used for bleeding ulcers in gastroenterology. This resulted in a sustained hemodynamic stabilization. The patient could be weaned off the balloon pump and catecholamines in the following three days. Echocardiography showed a stable minor pericardial effusion of 100?mL without any signs of hemodynamic relevance (Figure 1(b)). Unfortunately, on day nine, the patient gradually developed signs of progressive cardiogenic shock again with the need of cathecolamine treatment and finally died from pump failure on day 13. Serial echocardiographic evaluations were negative for relevant pericardial effusion. Autopsy revealed a fibrin glue induced focal peri-epicardial adhesion and extensive
Early Heparin Administration Reduces Risk for Left Atrial Thrombus Formation during Atrial Fibrillation Ablation Procedures
Stefan Asbach,Jürgen Biermann,Christoph Bode,Thomas S. Faber
Cardiology Research and Practice , 2011, DOI: 10.4061/2011/615087
Abstract: Objective. Despite the use of anticoagulation during left atrial (LA) ablation procedures, ischemic cerebrovascular accidents (CVAs) are recognized as a serious complication. Heparin is usually given after safe transseptal access has been obtained, resulting in a short unprotected dwell time of catheters within the LA, which may account for CVAs. We investigated the frequency of CVAs and LA thrombus formation as detected by intracardiac ultrasound (ICE) depending on the timing of heparin administration. Methods and Results. Sixty LA ablation procedures with the use of ICE were performed in 55 patients. Patients were grouped by heparin administration after (Group I, =13) and before (Group II, =47) transseptal access. Group I patients were younger (56.6±13.7 versus 65.9±9.9 years, =.01); other clinical and echocardiographic characteristics did not differ between groups. Early thrombus formation was observed in 2 (15.4%) of group I patients as compared to 0% of group II patients (=.04). One CVA (2.1%) occurred in one group II patient without prior thrombus detection, and none occurred in group I patients (=ns). Conclusion. Early administration of heparin reduces the risk of early intracardiac thrombus formation during LA ablation procedures. This did not result in reduced rate of CVAs.
Serotonin Antagonism Improves Platelet Inhibition in Clopidogrel Low-Responders after Coronary Stent Placement: An In Vitro Pilot Study
Daniel Duerschmied, Ingo Ahrens, Maximilian Mauler, Christoph Brandt, Stefanie Weidner, Christoph Bode, Martin Moser
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0032656
Abstract: Increased residual platelet reactivity remains a burden for coronary artery disease (CAD) patients who received a coronary stent and do not respond sufficiently to treatment with acetylsalicylic acid and clopidogrel. We hypothesized that serotonin antagonism reduces high on-treatment platelet reactivity. Whole blood impedance aggregometry was performed with arachidonic acid (AA, 0.5 mM) and adenosine diphosphate (ADP, 6.5 μM) in addition to different concentrations of serotonin (1–100 μM) in whole blood from 42 CAD patients after coronary stent placement and 10 healthy subjects. Serotonin increased aggregation dose-dependently in CAD patients who responded to clopidogrel treatment: After activation with ADP, aggregation increased from 33.7±1.3% to 40.9±2.0% in the presence of 50 μM serotonin (p<0.05) and to 48.2±2.0% with 100 μM serotonin (p<0.001). The platelet serotonin receptor antagonist ketanserin decreased ADP-induced aggregation significantly in clopidogrel low-responders (from 59.9±3.1% to 37.4±3.5, p<0.01), but not in clopidogrel responders. These results were confirmed with light transmission aggregometry in platelet-rich plasma in a subset of patients. Serotonin hence increased residual platelet reactivity in patients who respond to clopidogrel after coronary stent placement. In clopidogrel low-responders, serotonin receptor antagonism improved platelet inhibition, almost reaching responder levels. This may justify further investigation of triple antiplatelet therapy with anti-serotonergic agents.
Vector Selection of a Quadripolar Left Ventricular Pacing Lead Affects Acute Hemodynamic Response to Cardiac Resynchronization Therapy: A Randomized Cross-Over Trial
Stefan Asbach, Maximilian Hartmann, Tobias Wengenmayer, Erika Graf, Christoph Bode, Juergen Biermann
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0067235
Abstract: Background A suboptimal left ventricular (LV) pacing site may account for non-responsiveness of patients to cardiac resynchronization therapy (CRT). The vector selection of a novel quadripolar LV pacing lead, which was mainly developed to overcome technical issues with stimulation thresholds and phrenic nerve capture, may affect hemodynamic response, and was therefore assessed in this study. (German Clinical Trials Register DRKS00000573). Methods and Results Hemodynamic effects of a total of 145 LVPCs (9.1 per patient) of CRT devices with a quadripolar LV lead (Quartet?, St. Jude Medical) were assessed in 16/20 consecutive patients by invasive measurement of LV+dP/dtmax at an invasively optimized AV-interval in random order. Optimal (worst) LVPCs per patient were identified as those with maximal (minimal) %change in LV+dP/dtmax (%ΔLV+dP/dtmax) as compared to a preceding baseline. LV+dP/dtmax significantly increased in all 145 LVPCs (p<0.0001 compared to baseline) with significant intraindividual differences between LVPCs (p<0.0001). Overall, CRT acutely augmented %ΔLV+dP/dtmax by 31.3% (95% CI 24%–39%) in the optimal, by 21.3% (95% CI: 15%–27%) in the worst and by 28.2% (95% CI: 21%–36%) in a default distal LVPC. This resulted in an absolute additional acute increase in %ΔLV+dP/dtmax of 10.0% (95% CI: 7%–13%) of the optimal when compared to the worst (p<0.0001), and of 3.1% (95% CI: 1%–5%) of the optimal when compared to the default distal LVPC (p<0.001). Optimal LVPCs were not programmable with a standard bipolar lead in 44% (7/16) of patients. Conclusion The pacing configuration of a quadripolar LV lead determinates acute hemodynamic response. Pacing in the individually optimized configuration gives rise to an additional absolute 10% increase in %ΔLV+dP/dtmax when comparing optimal and worst vectors.
Acute Fluoxetine Treatment Induces Slow Rolling of Leukocytes on Endothelium in Mice
Nadine Herr, Maximilian Mauler, Thilo Witsch, Daniela Stallmann, Stefanie Schmitt, Julius Mezger, Christoph Bode, Daniel Duerschmied
PLOS ONE , 2014, DOI: 10.1371/journal.pone.0088316
Abstract: Objective Activated platelets release serotonin at sites of inflammation where it acts as inflammatory mediator and enhances recruitment of neutrophils. Chronic treatment with selective serotonin reuptake inhibitors (SSRI) depletes the serotonin storage pool in platelets, leading to reduced leukocyte recruitment in murine experiments. Here, we examined the direct and acute effects of SSRI on leukocyte recruitment in murine peritonitis. Methods C57Bl/6 and Tph1?/? (Tryptophan hydroxylase1) mice underwent acute treatment with the SSRI fluoxetine or vehicle. Serotonin concentrations were measured by ELISA. Leukocyte rolling and adhesion on endothelium was analyzed by intravital microscopy in mesentery venules with and without lipopolysaccharide challenge. Leukocyte extravasation in sterile peritonitis was measured by flow cytometry of abdominal lavage fluid. Results Plasma serotonin levels were elevated 2 hours after fluoxetine treatment (0.70±0.1 μg/ml versus 0.27±0.1, p = 0.03, n = 14), while serum serotonin did not change. Without further stimulation, acute fluoxetine treatment increased the number of rolling leukocytes (63±8 versus 165±17/0.04 mm2min?1) and decreased their velocity (61±6 versus 28±1 μm/s, both p<0.0001, n = 10). In Tph1?/? mice leukocyte rolling was not significantly influenced by acute fluoxetine treatment. Stimulation with lipopolysaccharide decreased rolling velocity and induced leukocyte adhesion, which was enhanced after fluoxetine pretreatment (27±3 versus 36±2/0.04 mm2, p = 0.008, n = 10). Leukocyte extravasation in sterile peritonitis, however, was not affected by acute fluoxetine treatment. Conclusions Acute fluoxetine treatment increased plasma serotonin concentrations and promoted leukocyte-endothelial interactions in-vivo, suggesting that serotonin is a promoter of acute inflammation. E-selectin was upregulated on endothelial cells in the presence of serotonin, possibly explaining the observed increase in leukocyte-endothelial interactions. However transmigration of neutrophils in sterile peritonitis was not affected by higher serotonin concentrations, indicating that the effect of fluoxetine was restricted to early steps in the leukocyte recruitment. Whether SSRI use in humans alters leukocyte recruitment remains to be investigated.
3D Conceptual Modelling and Direct Utilization Calculations of The Albanian Geothermal Resources  [PDF]
Nevton Kodhelaj, Aida Bode
Engineering (ENG) , 2013, DOI: 10.4236/eng.2013.51B037
Abstract: Balneological use of the Albanian Geothermal springs and waters dates back centuries, but the first modern use started in 1937. Unfortunately they had not been used for its energetic values yet. The temperature of the water is above 60 °C and the flow above 16 l/s, thus direct utilization is possible, in particular for space heating. Three-dimensional temperature field calculations and engineering calculations on a heating system with heat exchangers are presented here. The results show that the water temperature is expected to be stable and considerably higher temperature is expected through deep well drilling. The University’s Campus of Tirana is composed of 29 buildings, which are partially heated through a coal heater. The installed capacity is 2558kW while the coal consumption is about 920 kg/h. The University’s Campus of Tirana is one of the most important areas and with the highest density of population in Tirana, so it is the best area to show the heat exchanger efficiency. The economic analyses prove that the borehole heat exchangers are more convenient than the coal heating systems.
Circulating annexin V positive microparticles in patients after successful cardiopulmonary resuscitation
Katrin Fink, Linda Feldbrügge, Meike Schwarz, Natascha Bourgeois, Thomas Helbing, Christoph Bode, Tilmann Schwab, Hans-J?rg Busch
Critical Care , 2011, DOI: 10.1186/cc10512
Abstract: 36 patients after successful resuscitation, 20 control patients with stable cardiac disease and 15 healthy subjects were included prospectively. Two blood samples were drawn, one immediately and one 24 hours after return of spontaneous circulation (ROSC) to detect (annexin V+) monocyte-derived microparticles (MMPs) or procoagulant (annexin V+) platelet-derived microparticles (PMPs) and conjugates of endothelial-derived (annexin V+) microparticles (EMPs) with monocytes (EMP-MC) or platelets (EMP-PC). Measurements were performed by flow cytometric analysis. Additionally, the effect of isolated microparticles on cultured endothelial cells was assessed by ELISA.MMPs were significantly elevated immediately after ROSC compared to the cardiological control group (control; p < 0.01) and healthy subjects (healthy; p < 0.05) and persisted to be elevated in the following 24 hours after CPR (p < 0.05 vs. control and healthy, respectively). Procoagulant PMPs increased within the first 24 hours after ROSC (p < 0.01 vs. control and p < 0.005 vs. healthy). Conjugates of EMP with monocytes and platelets were both significantly elevated immediately after CPR (EMP-MC: p < 0.05 vs. control and p < 0.05 vs. healthy; EMP-PC: p < 0.05 vs. control and p < 0.05 vs. healthy), while only EMP-MC showed persisting high levels within 24 hours after CPR (p < 0.05 vs. control and p < 0.01 vs. healthy). MMP levels of ≥1.0/μL 24 hours after CPR predicted adverse outcome at 20 days (p < 0.05). Furthermore, isolated microparticles circulating in CPR patients early after ROSC led to enhanced endothelial apoptosis ex vivo compared to those of the healthy controls (p < 0.005).Resuscitated patients show substantially increased levels of different (annexin V+) microparticles and their conjugates immediately and 24 hours after cardiopulmonary resuscitation, suggesting an early onset of inflammation, an ongoing endothelial activation and a procoagulatory state. Additionally, microparticles of CPR patients ma
FoxP1 Stimulates Angiogenesis by Repressing the Inhibitory Guidance Protein Semaphorin 5B in Endothelial Cells
Sebastian Grundmann, Christian Lindmayer, Felix P. Hans, Imo Hoefer, Thomas Helbing, Gerard Pasterkamp, Christoph Bode, Dominique de Kleijn, Martin Moser
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0070873
Abstract: Forkhead box (Fox) transcription factors are important regulators of cardiovascular development and several Fox-proteins have recently been shown to modulate embryonic and post-natal angiogenesis. However, the role of the FoxP subfamily, which is highly expressed in cardiovascular tissue, has not been investigated so far. Here, we show that the transcription factor FoxP1 is the highest expressed FoxP-protein in endothelial cells and that it is upregulated at the site of neovascularization during hindlimb ischemia in mice. Silencing of FoxP1 results in a strong inhibition of proliferation, tube formation and migration of cultured endothelial cells. Accordingly, knockdown of FoxP1 in zebrafish was followed by a disruption of intersomitic vascular formation. Using gene expression profiling, we show that FoxP1 induces a specific change of the endothelial transcriptome and functions as a suppressor of semaphorin 5B, which has previously been described as a neuronal inhibitory factor. Our findings now demonstrate that semaphorin 5B also acts as a FoxP1- dependent suppressor of endothelial cell proliferation, migration and sprouting, mediating the effects of FoxP1. In summary, our data indicate that the transcription factor FoxP1 is essential for the angiogenic function of endothelial cells and functions as a suppressor of the inhibitory guidance cue semaphorin 5B, suggesting an important function of FoxP1 in the regulation of neovascularization.
Computer in surgery
CO Bode
Nigerian Journal of Surgical Research , 2004,
Abstract: Like most truly epochal revolutions, the computer age crept in on this generation before we could figure out its numerous possible applications. Over the past few years, an increasing appreciation of the usefulness of digital technology has emerged among various professions. How has the advent of the computer impacted the field of surgery? Is it worth embracing for the older practitioners? What does the future portend for our ancient noble profession? This paper reviews current applications of computer technology in the field of surgery and the hopes it hold out to surgeons in developing countries.
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