Search results for "Cardiology"

A hybrid stimulation strategy for suppression of spiral waves in cardiac tissue

2011

International audience; Atrial fibrillation (AF) is the most common cardiac arrhythmia whose mechanisms are thought to be mainly due to the self perpetuation of spiral waves (SW). To date, available treatment strategies (antiarrhythmic drugs, radiofrequency ablation of the substrate, electrical cardioversion) to restore and to maintain a normal sinus rhythm have limitations and are associated with AF recurrences. The aim of this study was to assess a way of suppressing SW by applying multifocal electrical stimulations in a simulated cardiac tissue using a 2D FitzHugh-Nagumo model specially convenient for AF investigations. We identified stimulation parameters for successful termination of S…

Changes in the Spectral Characteristics of Ventricular Fibrillation in Lesions Produced by Radiofrequency Ablation. An Experimental Study

2008

INTRODUCTION AND OBJECTIVES Although electro- physiological databases contain information about changes in the time domain in lesions produced by radiofrequency ablation, very few data on changes in the frequency domain are available. The aim of this study was to investigate changes in the spectral characteristics of ventricular fibrillation in zones with radiofrequency lesions. METHODS Recordings of ventricular fibrillation were obtained in 11 isolated perfused rabbit heart preparations using a multiple epicardial electrode located on the left ventricular free wall. Spectral parameters derived by Fourier analysis before and after the creation of transmural radiofrequency lesions were compa…

Personalized Cardiac Computational Models: From Clinical Data to Simulation of Infarct-Related Ventricular Tachycardia.

2019

In the chronic stage of myocardial infarction, a significant number of patients develop life-threatening ventricular tachycardias (VT) due to the arrhythmogenic nature of the remodeled myocardium. Radiofrequency ablation (RFA) is a common procedure to isolate reentry pathways across the infarct scar that are responsible for VT. Unfortunately, this strategy show relatively low success rates; up to 50% of patients experience recurrent VT after the procedure. In the last decade, intensive research in the field of computational cardiac electrophysiology (EP) has demonstrated the ability of three-dimensional (3D) cardiac computational models to perform in-silico EP studies. However, the personal…

Intestinal Ischemia: US-CT findings correlations.

2013

Background Intestinal ischemia is an abdominal emergency that accounts for approximately 2% of gastrointestinal illnesses. It represents a complex of diseases caused by impaired blood perfusion to the small and/or large bowel including acute arterial mesenteric ischemia (AAMI), acute venous mesenteric ischemia (AVMI), non occlusive mesenteric ischemia (NOMI), ischemia/reperfusion injury (I/R), ischemic colitis (IC). In this study different study methods (US, CT) will be correlated in the detection of mesenteric ischemia imaging findings due to various etiologies. Methods Basing on experience of our institutions, over 200 cases of mesenteric ischemia/infarction investigated with both US and …

Coronary artery and bypass flow measurement—basic methodology and current status

1998

Ventrolateral Compression of the Brain Stem in Essential Hypertension: MR Angiography Study

1997

Our purpose was to evaluate neurovascular compression at the level of ventrolateral medulla and NVC with the IXth and the Xth cranial nerves in patients with essential hypertension and in healthy volunteers using high resoluted Spoiled Recalled Gradient Echo (SPGR) sequences, allowing the detection of stationary tissues and moving spins. Thirty patients (19 men and 11 women) with essential hypertension were examined. Patient's ages ranged from 24 to 64 years-old (mean age was 48 y.o.). Patients older than 65 were excluded. The average of systolic blood-pressure of hypertensive patients was 183 ± 10 mmHg, while the diastolic pressure was 98 ± 10.5 mmHg. In conclusion, we consider axial sing…

Utility of post mortem MRI in definition of thrombus in aneurismatic coronary arteries due to incomplete Kawasaki Disease in infants

2016

Abstract Kawasaki disease (KD) is an acute, self-limited vasculitis of unknown etiology that primarily affects the coronary artery (CA) and presents in childhood. The characteristic coronary arterial lesion is an aneurysm, which may lead to thrombosis, dilatation, stenosis, and occlusion. Such an aneurysm is typically calcified and generally develops five or more years after the onset of acute KD. It becomes more noticeable after ten years. KD is sometimes difficult to diagnose because of the limited clinical features, especially in infants younger than 6 months old, where the clinical presentations often do not fulfill the diagnostic criteria for KD. We report a case of Incomplete Kawasaki…

A rare case of ruptured aneurysm of the paramedian artery of Percheron.

2018

Introduction The artery of Percheron is a rare anatomic variant supplying bilateral medial thalamic nuclei and a variable portion of the rostral part of midbrain. Case report A 48-year-old female with massive subarachnoid hemorrhage due to a ruptured aneurysm of the paramedian artery of Percheron presented to the emergency room. Because of significant risk of recurrent intracranial hemorrhage, it was decided to proceed with endovascular embolization of the aneurysm. The patient was ultimately sent to a rehabilitation center and her presenting neurologic deficits showed significant improvements in the weeks following endovascular embolization treatment. Discussion The paramedian artery of Pe…

Classification of Chimney EVAR-Related Endoleaks: Insights from the PERICLES Registry

2017

Juxtarenal aortic aneurysms (JAAs) pose significant challenges for endovascular aneurysm repair (EVAR). A short or absent infrarenal neck typically excludes standard EVAR as a viable or reasonable treatment option. In this context, the use of chimney grafts (chEVAR) is gaining in popularity and applicability. These grafts are designed to course in the aortic lumen outside the main stent-graft to maintain normal perfusion to the involved target branches. As such, they may represent a promising and less resource-intensive option for management of JAAs. However, this technical strategy is not without challenges of its own, particularly the inevitable creation of “gutters” that result from the …

0033 : Can cardiac troponin I measurement help to predict recent coronary occlusion in out-of-hospital cardiac arrest survivors?

2015

BackgroundRecent guidelines recommend the immediate performance of a coronary angiography when an acute myocardial infarction is suspected as a cause of out-of-hospital cardiac arrest. However, prehospital factors such as post resuscitation electrocardiogram pattern or clinical features are poorly sensitive in this setting. We searched to evaluate if a measurement of cardiac troponin I can help to detect a recent coronary lesion in out-of-hospital cardiac arrest.MethodsBetween January 2012 and Juin 2013, 54 out-of-hospital cardiac arrest survivors have been consecutively studied. An immediate coronary angiography has been systematically performed. Blood cardiac troponin I levels at admissio…