Biomedical subjects

K C Ueng

Publications and source records attributed to K C Ueng.

38 records · Page 3Linked to original sources

PubMed1995

The effects of accumulated experience on radiofrequency ablation of accessory pathways.

Increasing experience in radiofrequency ablation for accessory pathways appears to reduce the procedure time, radiation time and radiofrequency pulse number, and results in a higher success rate. However, the effect of a learning curve on this procedure from the perspective of location and conduction direction of accessory pathways has not been reported before. The purpose of this study was to determine the effect of accumulated experience on the outcomes of radiofrequency ablation for accessory pathways and on the duration of the procedure parameters by analyzing the results of a dedicated ablation team. The first 512 patients with a single accessory pathway treated in this laboratory were included for analysis of the procedure parameters with respect to locations and conduction directions of accessory pathways. The results showed that the average procedure time, radiation time, and radiofrequency pulse number differed significantly among the different subgroups (left free wall, right free wall, posteroseptal and anteromidseptal location; manifest or concealed conduction). All subgroups except the anteromidseptal pathways showed a significant improvement of the procedure parameters with increased ablation experience. Although the initial rate of improvement was similar among the different subgroups, the rate of improvement in left free wall pathways nearly reached a plateau after 120 ablation procedures. Thus it was concluded that a certain number of ablation procedures was necessary before achievement of a high success rate with shorter procedure and radiation times and a lower radiofrequency pulse number.

Catheter Ablation↗

PubMedDate not supplied

Electropharmacologic characteristics and radiofrequency catheter ablation of sustained ventricular tachycardia in patients without structural heart disease.

Twenty-six patients (mean age 39 +/- 17 years) with idiopathic sustained ventricular tachycardia (VT) were included for study. The patients were divided into two groups: group I: 14 patients with VT originating from the right ventricular outflow tract (wide QRS tachycardia with complete left bundle branch block pattern), and group II: 12 patients with VT originating from the left ventricle (wide QRS tachycardia with complete right bundle branch block pattern). Most of the group I patients (11/14) needed isoproterenol to facilitate induction of VT, and were sensitive to both verapamil and adenosine. Eight patients had successful radio-frequency (RF) ablation and were free of VT without any antiarrhythmic drugs. In group II, sustained VT was induced by programmed ventricular stimulation in all the patients (only 3 patients needed isoproterenol for facilitation); verapamil could terminate all the VT but none of the patients responded to adenosine. Eight patients received RF ablation and 6 patients had successful ablation without recurrent tachycardia on a long-term basis. Different sensitivity to adenosine and isoproterenol between right and left ventricular idiopathic VT suggested different underlying mechanisms for both types of VT. The patients who did not receive catheter ablation still had attacks of VT despite antiarrhythmic drug treatment; however, none of these patients had sudden death since the first attack of VT (mean 95 +/- 51 months), suggesting a benign prognosis in idiopathic VT.

Adolescent↗