Journal of cardiovascular electrophysiology
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J. Cardiovasc. Electrophysiol. · May 2001
Radiofrequency catheter ablation of idiopathic left ventricular outflow tract tachycardia: utility of intracardiac echocardiography.
The site of origin of idiopathic ventricular tachycardia (VT) arising from the left ventricular outflow tract (LVOT) may be closely related to the aortic valve leaflets, and radiofrequency (RF) delivery potentially can damage them. Intracardiac echocardiography (ICE) can identify accurately the ablation electrode and anatomic landmarks, and contact with the endocardium can be easily assessed. The aim of this study was to define the utility and the accuracy of ICE in guiding RF ablation of idiopathic VT of the LVOT. ⋯ Idiopathic VT of the LVOT can be treated successfully with RF ablation. ICE can accurately guide catheter ablation and identify anatomic landmarks, endocardial contact, and ablation electrode movement.
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J. Cardiovasc. Electrophysiol. · Apr 2001
Clinical TrialProblems of heart rate correction in assessment of drug-induced QT interval prolongation.
Estimation of QT interval prolongation belongs to safety assessment of every drug. Among unresolved issues, heart rate correction of the QT interval may be problematic. This article proposes a strategy for heart rate correction in drug safety studies and demonstrates the strategy using a study of ebastine, a nonsedating antihistamine. ⋯ Use of published heart rate correction formulas in the assessment of drug-induced QTc prolongation is inappropriate, especially when the drug might induce heart rate changes. Correction formulas optimized for pooled drug-free data are inferior to the formulas individualized for each subject. Measurement imprecision and natural variability can lead to mean QTc interval changes of 4 to 5 msec in the absence of drug treatment.
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J. Cardiovasc. Electrophysiol. · Apr 2001
Diagnosis of amiodarone pulmonary toxicity with high-resolution computerized tomographic scan.
Amiodarone pulmonary toxicity is a serious adverse effect that can be fatal. The diagnosis is difficult due to the nonspecificity of symptoms, clinical findings, and test results. Because of its high iodine content, amiodarone deposition can be detected by sensitive high-resolution computed tomographic (CT) scan techniques. We hypothesized that pulmonary toxicity can be diagnosed more readily when these scans indicate the presence of increased attenuation of either pleural or pulmonary densities representing high iodine amiodarone deposits. ⋯ High-resolution CT may be a valuable noninvasive test to aid in the diagnosis of amiodarone pulmonary toxicity in symptomatic patients.
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J. Cardiovasc. Electrophysiol. · Feb 2001
Clinical TrialUse of a saline-irrigated tip catheter for ablation of ventricular tachycardia resistant to conventional radiofrequency ablation: early experience.
Radiofrequency (RF) catheter ablation of ventricular tachycardia (VT) may fail if the critical isthmus is located intramyocardially or epicardially. The design of a saline-irrigated tip (SIT) catheter (Thermo-Cool, Cordis-Webster) involves active cooling of the tip electrode, which allows creation of larger ablation lesions. ⋯ The clinical target VT could be ablated using a SIT catheter in 5 (63%) of the 8 patients in whom ablation using a conventional RF catheter was unsuccessful. In the 2 patients with septal VT, a biventricular approach to mapping and ablation was required.
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J. Cardiovasc. Electrophysiol. · Jun 2000
Case ReportsPulmonary vein stenosis complicating catheter ablation of focal atrial fibrillation.
A recently described focal origin of atrial fibrillation, mainly inside pulmonary veins, is creating new perspectives for radiofrequency catheter ablation. However, pulmonary venous stenosis may occur with uncertain clinical consequences. This report describes a veno-occlusive syndrome secondary to left pulmonary vein stenosis after radiofrequency catheter ablation. ⋯ Multiple radiofrequency pulses applied inside the pulmonary veins ostia can induce severe pulmonary venous stenosis and veno-occlusive pulmonary syndrome.