131 research outputs found
Dependence of contrast to noise ratio between ablation scar and other tissues on patient heart rate and flip angle for late gadolinium enhancement imaging of the left atrium
Clinical and electrophysiologic characteristics of left septal atrial tachycardia
AbstractObjectivesIt was the purpose of this study to define the electrophysiologic (EP) identity of left septal atrial tachycardia (AT).BackgroundThe clinical and EP characteristics of this particular type of arrhythmia have not been fully described.MethodsA total of 120 patients with AT underwent invasive EP evaluation. Five patients (two men and three women; mean age 49 ± 15 years) with left septal AT were identified. Mapping of the right and left atrium was performed using conventional electrode catheters (five patients) and a three-dimensional electroanatomic mapping system (three patients) followed by radiofrequency (RF) ablation at the earliest site of local endocardial activation.ResultsFive tachycardias with a mean cycle length of 320 ± 94 ms were mapped, and the earliest endocardial electrogram occurred 22 ± 10 ms before the onset of the surface P-wave. Three left septal ATs were found to be originating from the left inferoposterior atrial septum and two from the left midseptum. During tachycardia, positive (three patients), biphasic negative-positive deflection (one patient), or isoelectric (one patient) P waves were recorded in lead V1. The inferior leads demonstrated a positive or biphasic P-wave morphology in four of five patients (80%). Four patients were given both adenosine and verapamil during AT. In three of four patients, verapamil successfully terminated AT after adenosine had failed. Adenosine successfully terminated AT in one of four patients. Successful RF ablation was performed in all patients (mean 2.2 ± 1.7 RF applications) without affecting atrioventricular conduction properties. No recurrence of AT was observed after a mean follow-up of 14 ± 8 months.ConclusionsLeft septal AT ablation is safe and effective. There was no consistent P-wave morphology associated with this particular type of AT. This arrhythmia appears to be resistant to adenosine and moderately responsive to calcium antagonists
Dependence of image quality of late gadolinium enhancement MRI of left atrium on number of patients imaged: results of multi-center trial DECAAF
Use of a dark blood sequence to localize the esophagus prior to RF ablation and to assess left atrial edema post ablation
Visibility of RF ablation lesions in native T1-weighted MRI reduces with time after ablation
High infusion rate of isoproterenol in patients with atrial fibrillation: frequent evidence of firing from multiple veins
Left atrial late gadolinium enhancement following external beam radiation for lymphoma: a potential model for exploring radiation-related heart disease
Pulmonary vein stenosis detection by early cardiac magnetic resonance imaging post-atrial fibrillation ablation
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