The Experts below are selected from a list of 222 Experts worldwide ranked by ideXlab platform

Shihann Chen - One of the best experts on this subject based on the ideXlab platform.

  • is 8 mm more effective than 4 mm tip Electrode Catheter for ablation of typical atrial flutter
    Circulation, 1999
    Co-Authors: Chinfeng Tsai, Wenchung Yu, Yi Jen Chen, Minghsiung Hsieh, Chernen Chiang, Yuan Ding, Mausong Chang, Shihann Chen
    Abstract:

    Background —The prospective, randomized study comparing 4- with 8-mm tip Electrodes for radiofrequency linear ablation of typical atrial flutter is not available. Methods and Results —A total of 104 consecutive patients with typical atrial flutter were randomly assigned to undergo radiofrequency linear ablation using a 4- (Group I, n=54) or 8-mm tip Electrode (Group II, n=50) Catheter (temperature-control model, preset 70°C). If complete bidirectional isthmus block could not be achieved after 5 pulses, the ablation Catheter was changed to the other type; the maximal radiofrequency pulse number was limited to <10 pulses. Complete or incomplete isthmus conduction block was assessed by activation sequence in a multiElectrode Halo Catheter during low lateral right atrial and proximal coronary sinus pacing. Before shifting to the other Catheter type, the 8-mm Electrode Catheter achieved higher complete isthmus block rate (92% versus 67%, P <0.05) with fewer pulses (2±1 versus 3±1, P <0.05), shorter procedure time (24±15 versus 31±12 minutes, P <0.05), and shorter fluoroscopic time (14±10 versus 23±15 minutes, P <0.05). After 5 failed ablation pulses, 12 (67%) of 18 patients in group I attained complete isthmus block by using an 8-mm tip Catheter, but none of 4 patients in group II achieved complete block by changing to a 4-mm tip Catheter. Conclusions —The 8-mm tip Electrodes are more effective than the standard 4-mm length Electrodes in linear ablation for typical atrial flutter. This clinical benefit may be of particular value for some patients with broad and/or thick isthmus.

  • Is 8-mm More Effective Than 4-mm Tip Electrode Catheter for Ablation of Typical Atrial Flutter?
    Circulation, 1999
    Co-Authors: Chinfeng Tsai, Wenchung Yu, Yi Jen Chen, Minghsiung Hsieh, Chernen Chiang, Yuan Ding, Mausong Chang, Shihann Chen
    Abstract:

    Background —The prospective, randomized study comparing 4- with 8-mm tip Electrodes for radiofrequency linear ablation of typical atrial flutter is not available. Methods and Results —A total of 104 consecutive patients with typical atrial flutter were randomly assigned to undergo radiofrequency linear ablation using a 4- (Group I, n=54) or 8-mm tip Electrode (Group II, n=50) Catheter (temperature-control model, preset 70°C). If complete bidirectional isthmus block could not be achieved after 5 pulses, the ablation Catheter was changed to the other type; the maximal radiofrequency pulse number was limited to

Enno T Van Der Velde - One of the best experts on this subject based on the ideXlab platform.

  • endocardial activation mapping of ventricular tachycardia in patients first application of a 32 site bipolar mapping Electrode Catheter
    Circulation, 1998
    Co-Authors: Martin J Schalij, Paul F Van Rugge, Machiel A Siezenga, Enno T Van Der Velde
    Abstract:

    Background—Localization of early activated endocardial areas during ventricular tachycardia (VT) is mandatory for performance of surgical or radiofrequency Catheter interventions. The use of a multiElectrode Catheter may shorten the procedure time and increase the accuracy of the procedure compared with single-Electrode mapping techniques. This study was performed to evaluate the safety and efficacy of a 32-bipolar-Electrode mapping Catheter in patients. Methods and Results—The basket-shaped mapping Catheter (BMC), integrated with a computerized mapping system, allowed on-line reconstruction of endocardial activation maps. Twenty patients with VT were studied before surgery (n=4) or radiofrequency Catheter ablation (n=16). End-diastolic left ventricular (LV) volume was 280±120 mL, with an LV ejection fraction of 33±14%. The volume encompassed by the BMC was 164±27 mL (130 to 200 mL); the deployment time was 46±11 minutes. Endocardial activation time during sinus rhythm was 105±34 ms; 14±5 Electrodes could...

Melvin M. Scheinman - One of the best experts on this subject based on the ideXlab platform.

  • ablation of the atrioventricular junction with radiofrequency energy using a new Electrode Catheter
    American Journal of Cardiology, 1991
    Co-Authors: Jonathan J Langberg, Michael Chin, David J Schamp, Jeffrey Goldberger, David N Pederson, Michael Oeff, Michael D Lesh, Jerry C Griffin, Melvin M. Scheinman
    Abstract:

    Abstract Percutaneous Catheter ablation using radiofrequency energy can be used to interrupt atrioventricular (AV) conduction in patients with supraventricular tachycardia refractory to drugs. Results of radiofrequency ablation of the AV junction using a custom-designed Catheter with a large, 3-mm-long distal Electrode, 2-mm interElectrode spacing, and a shaft with increased torsional rigidity were compared with those using a standard quadripolar Electrode Catheter (Bard EP). An electrocoagulator (Microvasive Bicap 4005) supplied unmodulated radiofrequency current at 550 kHz, which was applied between the distal Electrode of the ablation Catheter and a large skin Electrode. With use of the modified Catheter, 12 of 13 patients (92%) had persistent complete AV block induced with 7 ± 5 applications of 18 ± 6 W of radiofrequency power. In contrast, complete AV block was produced in only 9 of 18 (50%) historical control patients treated with the standard Catheter, despite a similar number of applications (7 ± 5) and power output (16 ± 4 W). A rise in impedance, due to desiccation of tissue and coagulum formation, occurred earlier (28 ± 18 vs 52 ± 24 seconds, p

Chinfeng Tsai - One of the best experts on this subject based on the ideXlab platform.

  • is 8 mm more effective than 4 mm tip Electrode Catheter for ablation of typical atrial flutter
    Circulation, 1999
    Co-Authors: Chinfeng Tsai, Wenchung Yu, Yi Jen Chen, Minghsiung Hsieh, Chernen Chiang, Yuan Ding, Mausong Chang, Shihann Chen
    Abstract:

    Background —The prospective, randomized study comparing 4- with 8-mm tip Electrodes for radiofrequency linear ablation of typical atrial flutter is not available. Methods and Results —A total of 104 consecutive patients with typical atrial flutter were randomly assigned to undergo radiofrequency linear ablation using a 4- (Group I, n=54) or 8-mm tip Electrode (Group II, n=50) Catheter (temperature-control model, preset 70°C). If complete bidirectional isthmus block could not be achieved after 5 pulses, the ablation Catheter was changed to the other type; the maximal radiofrequency pulse number was limited to <10 pulses. Complete or incomplete isthmus conduction block was assessed by activation sequence in a multiElectrode Halo Catheter during low lateral right atrial and proximal coronary sinus pacing. Before shifting to the other Catheter type, the 8-mm Electrode Catheter achieved higher complete isthmus block rate (92% versus 67%, P <0.05) with fewer pulses (2±1 versus 3±1, P <0.05), shorter procedure time (24±15 versus 31±12 minutes, P <0.05), and shorter fluoroscopic time (14±10 versus 23±15 minutes, P <0.05). After 5 failed ablation pulses, 12 (67%) of 18 patients in group I attained complete isthmus block by using an 8-mm tip Catheter, but none of 4 patients in group II achieved complete block by changing to a 4-mm tip Catheter. Conclusions —The 8-mm tip Electrodes are more effective than the standard 4-mm length Electrodes in linear ablation for typical atrial flutter. This clinical benefit may be of particular value for some patients with broad and/or thick isthmus.

  • Is 8-mm More Effective Than 4-mm Tip Electrode Catheter for Ablation of Typical Atrial Flutter?
    Circulation, 1999
    Co-Authors: Chinfeng Tsai, Wenchung Yu, Yi Jen Chen, Minghsiung Hsieh, Chernen Chiang, Yuan Ding, Mausong Chang, Shihann Chen
    Abstract:

    Background —The prospective, randomized study comparing 4- with 8-mm tip Electrodes for radiofrequency linear ablation of typical atrial flutter is not available. Methods and Results —A total of 104 consecutive patients with typical atrial flutter were randomly assigned to undergo radiofrequency linear ablation using a 4- (Group I, n=54) or 8-mm tip Electrode (Group II, n=50) Catheter (temperature-control model, preset 70°C). If complete bidirectional isthmus block could not be achieved after 5 pulses, the ablation Catheter was changed to the other type; the maximal radiofrequency pulse number was limited to

Hitonobu Tomoike - One of the best experts on this subject based on the ideXlab platform.

  • Continuous measurement of left ventricular volume in rabbit, using a two-Electrode Catheter
    Heart and Vessels, 1995
    Co-Authors: Jun Ohtomo, Ichiro Yamaguchi, Eiji Tsuchida, Toshihiro Fujinuma, Kenji Sunagawa, Hitonobu Tomoike
    Abstract:

    We developed a device for monitoring instantaneous left ventricular (LV) volume using an alternating-current excitation two-Electrode conductance Catheter. Instantaneous conductance between a pair of Electrodes was amplified by a noninverting circuit. The level of conductance was linearly related to changes in blood volume from 0.8 to 2.0ml in a latex balloon ( r ^2 = 0.95), and to changes in blood volume from 0.4 to 2.2ml in a post-mortem rabbit left ventricle ( r ^2 = 0.99). The difference between the maximal and minimal conductance of the LV in situ during a cardiac cycle was closely correlated with changes in stroke volume, measured by an electromagnetic flow probe ( r ^2 = 0.97). The endsystolic pressure-conductance relation (ESPCR) was highly linear ( r ^2 = 0.92). Changes of the slope (Ees) of the ESPCR correlated directionally with changes of the time derivative of LV pressure (LVdP/dt) during intravenous infusions of dobutamine and propranolol. Accordingly, the two-Electrode conductance Catheter was useful in vivo in rabbits for continuously assessing changes in the LV volume.