First in Human Clinical Feasibility Study of Endovascular Navigation with Fiber Optic RealShape (FORS) Technology.

Objective: Endovascular procedures are conventionally conducted using two dimensional fluoroscopy. A new technology platform, Fiber Optic RealShape (FORS), has recently been introduced allowing real time, three dimensional visualisation of endovascular devices using fiberoptic technology. It functions as an add on to conventional fluoroscopy and may facilitate endovascular procedures.

Dynamic coronary roadmapping during percutaneous coronary intervention: a feasibility study.

Background: A novel software ("Dynamic Coronary Roadmap") was developed, which offers a real-time, dynamic overlay of the coronary tree on fluoroscopy. Once the roadmap has been automatically generated during angiography it can be used for navigation during percutaneous coronary interventions (PCI). As a feasibility study, we aimed to investigate the feasibility of real-time dynamic coronary roadmapping and consecutive coronary overlay during elective PCI.

Novel System for Real-Time Integration of 3-D Echocardiography and Fluoroscopy for Image-Guided Cardiac Interventions: Preclinical Validation and Clinical Feasibility Evaluation.

Real-time imaging is required to guide minimally invasive catheter-based cardiac interventions. While transesophageal echocardiography allows for high-quality visualization of cardiac anatomy, X-ray fluoroscopy provides excellent visualization of devices. We have developed a novel image fusion system that allows real-time integration of 3-D echocardiography and the X-ray fluoroscopy.

New image processing and noise reduction technology allows reduction of radiation exposure in complex electrophysiologic interventions while maintaining optimal image quality: a randomized clinical trial.

Background: Despite their carcinogenic potential, X-rays remain indispensable for electrophysiologic (EP) procedures.

Objective: The purpose of this study was to evaluate the dose reduction and image quality of a novel X-ray technology using advanced image processing and dose reduction technology in an EP laboratory.

Methods: In this single-center, randomized, unblinded, parallel controlled trial, consecutive patients undergoing catheter ablation for complex arrhythmias were eligible.

Extended-field-of-view three-dimensional transesophageal echocardiography using image-based X-ray probe tracking.

The use of ultrasound imaging for guidance of cardiac interventional procedures is limited by the small field of view of the ultrasound volume. A larger view can be created by image-based registration of several partially overlapping volumes, but automatic registration is likely to fail unless the registration is initialized close to the volumes' correct alignment. In this article, we use X-ray images to track a transesophageal ultrasound probe and thereby provide initial position information for the registration of the ultrasound volumes.

Limited angle C-arm tomography and segmentation for guidance of atrial fibrillation ablation procedures.

Angiographic projections of the left atrium (LA) and the pulmonary veins (PV) acquired with a rotational C-arm system are used for 3D image reconstruction and subsequent automatic segmentation of the LA and PV to be used as roadmap in fluoroscopy guided LA ablation procedures. Acquisition of projections at high oblique angulations may be problematic due to increased collision danger of the detector with the right shoulder of the patient. We investigate the accuracy of image reconstruction and model based roadmap segmentation using limited angle C-arm tomography.

An integrated platform for image-guided cardiac resynchronization therapy.

Cardiac resynchronization therapy (CRT) is an effective procedure for patients with heart failure but 30% of patients do not respond. This may be due to sub-optimal placement of the left ventricular (LV) lead. It is hypothesized that the use of cardiac anatomy, myocardial scar distribution and dyssynchrony information, derived from cardiac magnetic resonance imaging (MRI), may improve outcome by guiding the physician for optimal LV lead positioning.

Cardiac resynchronization therapy with individualized placement of two left ventricular leads at the sites of latest mechanical left ventricular contraction: guided by 3D-echocardiography and coronary sinus rotation angiography.

A 78-year-old woman with dilated cardiomyopathy was admitted for advanced dyspnoea and recurrent cardiac decompensation despite optimal medical therapy. Implantation of a cardiac resynchronization therapy (CRT) device was indicated according to current guidelines. The day before CRT implantation, three-dimensional echocardiography was performed together with coronary sinus (CS) rotation angiography, which identified two sites of latest mechanical left ventricular (LV) contraction with adjacently available target veins.

Three-dimensional CT overlay in comparison to CartoMerge for pulmonary vein antrum isolation.

Introduction: Three-dimensional (3D) navigation systems are widely used for pulmonary vein antrum isolation (PVAI). To circumvent left atrial (LA) mapping, 3D CT reconstructions of the LA can be superimposed directly (CT overlay) on the fluoroscopy image to guide ablation catheters and to mark ablation sites.

Methods And Results: Sixty-eight patients (pts) with symptomatic AF refractory to medical therapy were randomly assigned to CT overlay (group 1, n = 38) or CartoMerge (group 2, n = 30).

Concanavalin A inhibits pathophysiological effects of anti-ganglioside GQ1b antibodies at the mouse neuromuscular synapse.

Anti-GQ1b antibodies are present in the Miller Fisher syndrome (MFS), a monophasic neuropathy characterized by ataxia, areflexia, ophthalmoplegia, and sometimes cranial muscle weakness. We have previously shown, at the mouse neuromuscular junction (NMJ) ex vivo, that anti-GQ1b antibodies, through complement classic pathway activation, block synaptic transmission in a way that resembles the effect of the pore-forming alpha-latrotoxin (alphaLTx). In order to clarify the mechanism of these alphaLTx-like effects, including possible involvement of the alternative and mannose-binding protein complement pathways, we studied the effects of concanavalin A (ConA), a lectin known to block the action of alphaLTx, immunoglobulins, and early complement components.

Calpain inhibitors protect against axonal degeneration in a model of anti-ganglioside antibody-mediated motor nerve terminal injury.

Miller Fisher syndrome-associated anti-GQ1b ganglioside antibodies produce an acute complement-dependent neuroexocytic effect at the mouse neuromuscular junction (NMJ) that closely resembles the effect of alpha-latrotoxin (LTx). This pathophysiological effect is accompanied by morphological disruption of the nerve terminal involving the loss of major cytoskeletal components, including neurofilament. Both LTx and the membrane attack complex of complement form membrane pores that allow free ionic movement and we have previously hypothesized that Ca2+ ingress and the subsequent activation of Ca2+-dependent proteases, calpains, may lead to substrate degradation resulting in structural disorganization of the terminal.

Immunoglobulins inhibit pathophysiological effects of anti-GQ1b-positive sera at motor nerve terminals through inhibition of antibody binding.

High-dose intravenous immunoglobulin (IVIg) is an effective treatment for many antibody-mediated neuromuscular diseases, suggesting that IVIg directly interferes with the pathways through which the pathogenic antibodies exert their effects. However, the precise mechanisms of action are unclear. Serum anti-GQ1b antibodies are strongly associated with ophthalmoplegia in patients with Miller Fisher syndrome (MFS) and Guillain-Barré syndrome (GBS).

Complex gangliosides as autoantibody targets at the neuromuscular junction in Miller Fisher syndrome: a current perspective.

Glycosphingolipid biology has increasingly interfaced with the field of human autoimmune neuropathy over the last two decades. There are currently over 20 distinct glycolipids that have been identified as autoantibody targets in a wide range of clinical neuropathy syndromes. This review sets out the clinical and experimental background to one interesting example of anti-glycolipid antibody-associated neuropathy termed Miller Fisher syndrome.

Complex gangliosides at the neuromuscular junction are membrane receptors for autoantibodies and botulinum neurotoxin but redundant for normal synaptic function.

One specialization of vertebrate presynaptic neuronal membranes is their multifold enrichment in complex gangliosides, suggesting that these sialoglycolipids may play a major functional role in synaptic transmission. We tested this hypothesis directly by studying neuromuscular synapses of mice lacking complex gangliosides attributable to deletion of the gene coding for beta1,4 GalNAc-transferase (GM2/GD2 synthase), which catalyzes an early step in ganglioside synthesis. Our studies show that complex gangliosides are surprisingly redundant for regulated neurotransmitter release under normal physiological conditions.

Detection and prevalence of alpha-latrotoxin-like effects of serum from patients with Guillain-Barré syndrome.

Anti-GQ1b antibodies are associated with the Miller Fisher syndrome (MFS), a variant of the Guillain-Barré syndrome (GBS). In the ex vivo mouse diaphragm, anti-GQ1b-positive MFS serum induces muscle fiber twitching, a temporary dramatic increase of spontaneous quantal acetylcholine release, and transmission blockade at neuromuscular junctions (NMJs). These effects resemble those of alpha-latrotoxin (alpha-LTx) and are induced by antibody-mediated activation of complement.