The Experts below are selected from a list of 669 Experts worldwide ranked by ideXlab platform
Josef Kautzner - One of the best experts on this subject based on the ideXlab platform.
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Local Electrogram delay recorded from left ventricular lead at implant predicts response to cardiac resynchronization therapy retrospective study with 1 year follow up
BMC Cardiovascular Disorders, 2012Co-Authors: Rostislav Polasek, Pavel Kucera, Pavel Nedbal, Tomas Roubicek, Tomas Belza, Jana Hanuliakova, David Horak, Dan Wichterle, Josef KautznerAbstract:Background Considerable proportion of patients does not respond to the cardiac resynchronization therapy (CRT). This study investigated clinical relevance of left ventricular electrode Local Electrogram delay from the beginning of QRS (QLV). We hypothesized that longer QLV indicating more optimal lead placement in the late activated regions is associated with the higher probability of positive CRT response.
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Local Electrogram delay recorded from left ventricular lead at implant predicts response to cardiac resynchronization therapy retrospective study with 1 year follow up
BMC Cardiovascular Disorders, 2012Co-Authors: Rostislav Polasek, Pavel Kucera, Pavel Nedbal, Tomas Roubicek, Tomas Belza, Jana Hanuliakova, David Horak, Dan Wichterle, Josef KautznerAbstract:Considerable proportion of patients does not respond to the cardiac resynchronization therapy (CRT). This study investigated clinical relevance of left ventricular electrode Local Electrogram delay from the beginning of QRS (QLV). We hypothesized that longer QLV indicating more optimal lead placement in the late activated regions is associated with the higher probability of positive CRT response. We conducted a retrospective, single–centre analysis of 161 consecutive patients with heart failure and LBBB or nonspecific intraventricular conduction delay (IVCD) treated with CRT. We routinely intend to implant the LV lead in a region with long QLV. Clinical response to CRT, left ventricular (LV) reverse remodelling (i.e. decrease in LV end-systolic diameter - LVESD ≥10%) and reduction in plasma level of NT-proBNP >30% at 12-month post-implant were the study endpoints. We analyzed association between pre-implant variables and the study endpoints. Clinical CRT response rate reached 58%, 84% and 92% in the lowest (≤105 ms), middle (106-130 ms) and the highest (>130 ms) QLV tertile (p < 0.0001), respectively. Longer QRS duration (p = 0.002), smaller LVESD and a non-ischemic cardiomyopathy (both p = 0.02) were also univariately associated with positive clinical CRT response. In a multivariate analysis, QLV remained the strongest predictor of clinical CRT response (p < 0.00001), followed by LVESD (p = 0.01) and etiology of LV dysfunction (p = 0.04). Comparable predictive power of QLV for LV reverse remodelling and NT-proBNP response rates was observed. LV lead position assessed by duration of the QLV interval was found the strongest independent predictor of beneficial clinical response to CRT.
Wen Pin Lien - One of the best experts on this subject based on the ideXlab platform.
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radiofrequency catheter ablation of septal accessory pathways within the triangle of koch importance of energy titration testing other than the Local Electrogram characteristics for identifying the successful target site
Pacing and Clinical Electrophysiology, 1998Co-Authors: Jiunn Lee Lin, Yungzu Tseng, Shoei Stephen K Huang, Ling Ping Lai, Ting Fu Cheng, Wen Pin LienAbstract:Radiofrequency (RF) catheter ablation of accessory atrioventricular (AV) connections in the proximity of His bundle or AV node is at high risk of developing complete heart block. A safe and effective protocol has not been well established. Nineteen consecutive patients with 19 septal accessory pathways within the triangle of Koch underwent a protocol with power-titrated RF energy testing to identify the target site for successful catheter ablation. At every potential target site preselected by Local Electrogram characteristics, RF energy was started at 5 W for 10 seconds, with an increment of 5 W (duration remained at 10 s) until maximally 30 W or the observation of transient interruption of accessory pathway conduction. By this stepwise RF energy testing, we successfully Localized and ablated 18 (94.7%) of the 19 septal accessory pathways, 10 close to His bundle (zone I) and 8 away from it (zone II). The test-effective RF power was 20 W or less in 9 of all 11 septal accessory pathways in zone I, and 5 of the 8 in zone II (P = 0.68). Meanwhile, the final RF power for successful ablation was 30 W or less in 9 of the 10 zone I and 6 of the 8 zone II septal accessory pathways (P = 0.83). One patient with an accessory pathway in zone I was complicated with complete AV block after final ablation at 30 W. None of the Local Electrogram characteristics except continuous electrical activity during retrograde mapping was helpful in the prediction of ablation outcome. Careful RF energy titration testing could effectively help identify the target site for successful RF catheter ablation of septal accessory pathways within the triangle of Koch. The dependence on Local Electrogram manifestations could be frustrated by a low probability of success.
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value of Local Electrogram characteristics predicting successful catheter ablation of left versus right sided accessory atrioventricular pathways by radiofrequency current
The Cardiology, 1995Co-Authors: Jiunn Lee Lin, Jen Tsong Schie, Chuen Den Tseng, Wenjone Chen, Tin Fu Cheng, Shi Sheng Tsou, Jin Jer Chen, Yungzu Tseng, Wen Pin LienAbstract:Despite similar guidance by Local Electrogram criteria, catheter ablation of right-sided accessory atrioventricular (AV) pathways by radiofrequency current has been less effective than that of left-sided ones. In order to elucidate the possible diversities in Local electrosignal criteria, we systematically analyzed the morphological and timing characteristics of 215 bipolar Local Electrograms from catheter ablation sites of 65 left-sided accessory AV pathways and of 356 from those of 37 right-sided ones in 92 consecutive patients with Wolff-Parkinson-White syndrome or AV reentrant tachycardia incorporating concealed accessory AV pathways. After stepwise multivariate analysis, we selected the presence of a possible accessory pathway potential, Local ventricular activation preceding QRS complex for 20 ms or more during ventricular insertion mapping, and the Local retrograde ventriculoatrial (VA) continuity, Local retrograde VA interval ≤ 50 ms, Electrogram stability (left-sided targets only), retrograde accessory pathway potential (right-sided targets only) during atrial insertion mapping, as independent Local Electrogram predictors for successful ablation of left- and right-sided accessory AV pathways. Combination of all Local Electrogram predictors could have moderate chance of success (80 and 51 %) for the ventricular and atrial insertion ablation of left-sided accessory AV pathways, but only low probability of success (40% in ventricular insertion ablation) or very low sensitivity (12.5% in atrial insertion ablation) for right-sided ones. In conclusion, with the present approach, successful catheter ablation of right-sided accessory AV pathways, compared to left-sided ones, still necessitate a breakthrough in the precision mapping and the efficiency of energy delivery.
Rostislav Polasek - One of the best experts on this subject based on the ideXlab platform.
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Local Electrogram delay recorded from left ventricular lead at implant predicts response to cardiac resynchronization therapy retrospective study with 1 year follow up
BMC Cardiovascular Disorders, 2012Co-Authors: Rostislav Polasek, Pavel Kucera, Pavel Nedbal, Tomas Roubicek, Tomas Belza, Jana Hanuliakova, David Horak, Dan Wichterle, Josef KautznerAbstract:Background Considerable proportion of patients does not respond to the cardiac resynchronization therapy (CRT). This study investigated clinical relevance of left ventricular electrode Local Electrogram delay from the beginning of QRS (QLV). We hypothesized that longer QLV indicating more optimal lead placement in the late activated regions is associated with the higher probability of positive CRT response.
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Local Electrogram delay recorded from left ventricular lead at implant predicts response to cardiac resynchronization therapy retrospective study with 1 year follow up
BMC Cardiovascular Disorders, 2012Co-Authors: Rostislav Polasek, Pavel Kucera, Pavel Nedbal, Tomas Roubicek, Tomas Belza, Jana Hanuliakova, David Horak, Dan Wichterle, Josef KautznerAbstract:Considerable proportion of patients does not respond to the cardiac resynchronization therapy (CRT). This study investigated clinical relevance of left ventricular electrode Local Electrogram delay from the beginning of QRS (QLV). We hypothesized that longer QLV indicating more optimal lead placement in the late activated regions is associated with the higher probability of positive CRT response. We conducted a retrospective, single–centre analysis of 161 consecutive patients with heart failure and LBBB or nonspecific intraventricular conduction delay (IVCD) treated with CRT. We routinely intend to implant the LV lead in a region with long QLV. Clinical response to CRT, left ventricular (LV) reverse remodelling (i.e. decrease in LV end-systolic diameter - LVESD ≥10%) and reduction in plasma level of NT-proBNP >30% at 12-month post-implant were the study endpoints. We analyzed association between pre-implant variables and the study endpoints. Clinical CRT response rate reached 58%, 84% and 92% in the lowest (≤105 ms), middle (106-130 ms) and the highest (>130 ms) QLV tertile (p < 0.0001), respectively. Longer QRS duration (p = 0.002), smaller LVESD and a non-ischemic cardiomyopathy (both p = 0.02) were also univariately associated with positive clinical CRT response. In a multivariate analysis, QLV remained the strongest predictor of clinical CRT response (p < 0.00001), followed by LVESD (p = 0.01) and etiology of LV dysfunction (p = 0.04). Comparable predictive power of QLV for LV reverse remodelling and NT-proBNP response rates was observed. LV lead position assessed by duration of the QLV interval was found the strongest independent predictor of beneficial clinical response to CRT.
Francis E Marchlinski - One of the best experts on this subject based on the ideXlab platform.
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anatomic characterization of endocardial substrate for hemodynamically stable reentrant ventricular tachycardia identification of endocardial conducting channels
Heart Rhythm, 2006Co-Authors: Henry H Hsia, David J Callans, David Lin, William H Sauer, Francis E MarchlinskiAbstract:Background Detailed anatomic characterization of endocardial substrate of ventricular tachycardia (VT) is limited. Objectives The purpose of this study was to determine the endocardial dimensions and Local Electrogram voltage characteristics of the reentrant circuit. VT-related conducting channels corresponding to zones of slow conduction may be identified. Methods Electroanatomic mapping was performed in 26 patients with uniform VT. Entrainment mapping was performed in 53 VTs, of which 19 entrance, 37 isthmus, 48 exit, and 32 outer loop sites were identified. The color display of voltage maps was adjusted to identify conducting channels associated with VT circuits. A conducting channel was defined as a path of multiple orthodromically activated sites within the VT circuit that demonstrated an Electrogram amplitude higher than that of surrounding areas as evidenced by voltage color differences. Results Forty-seven (84%) of 56 entrance or isthmus sites were located within dense scar ( Conclusion (1) Most entrance and isthmus sites of hemodynamically stable VT are located in dense scar, whereas exits are located in the border zone. (2) VT-related conducting channels may be identified by careful voltage threshold adjustment. These findings have important implications regarding strategies for substrate-based VT ablation.
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effect of bundle branch block on Local Electrogram morphologic features implications for arrhythmia diagnosis by stored Electrogram analysis
American Heart Journal, 1996Co-Authors: Brian H Sarter, Bruce G Hook, David J Callans, Francis E MarchlinskiAbstract:Abstract Analysis of stored Local ventricular Electrogram recordings is a useful diagnostic tool in the evaluation of patients with implantable cardioverter defibrillators. Visual analysis of Local Electrogram morphologic features has been demonstrated to be useful in distinguishing ventricular tachycardia from supraventricular rhythm. The effect of bundle branch block (BBB) aberration during supraventricular tachycardia on Local Electrogram morphologic features is not entirely clear. Erroneous diagnoses resulting from a change in Electrogram morphologic features with BBB may occur. To determine whether the development of BBB can produce a change in Local Electrogram morphologic features and whether this change is dependent on the site of recording, we retrospectively reviewed Local Electrogram recordings from 23 patients who had intermittent BBB during electrophysiologic evaluation of documented or suspected supraventricular tachycardia. Local Electrogram recordings from catheters placed in the right ventricular apex and coronary sinus during supraventricular tachycardia with BBB aberrancy were compared with recordings during narrow complex supraventricular tachycardia or normal sinus rhythm. Bipolar recordings were made with a 5 mm inter-electrode distance with filter settings at 40 to 400 Hz. Three independent blinded observers defined the paired Electrograms as the same or distinctly different. During right BBB a change in Electrogram morphologic features was demonstrated in 11 (85%) of 13 recordings from the right ventricular apex and in only 1 (8%) of 12 recordings from the coronary sinus. In contrast, during left BBB a change in Electrogram morphologic features was seen in 6 (100%) of 6 recordings from the coronary sinus and in only 1 (8%) of 13 recordings from the right ventricular apex. These results demonstrate that when the described recording techniques are used, a change in Local ventricular Electrogram morphologic features during BBB is predominantly manifest in recording sites ipsilateral to the BBB, whereas recording sites contralateral to the BBB are relatively unaffected. This information may have implications regarding interpretation of stored Electrograms when an attempt is made to establish a rhythm diagnosis leading to implantable cardioverter defibrillator therapy.
Jiunn Lee Lin - One of the best experts on this subject based on the ideXlab platform.
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radiofrequency catheter ablation of septal accessory pathways within the triangle of koch importance of energy titration testing other than the Local Electrogram characteristics for identifying the successful target site
Pacing and Clinical Electrophysiology, 1998Co-Authors: Jiunn Lee Lin, Yungzu Tseng, Shoei Stephen K Huang, Ling Ping Lai, Ting Fu Cheng, Wen Pin LienAbstract:Radiofrequency (RF) catheter ablation of accessory atrioventricular (AV) connections in the proximity of His bundle or AV node is at high risk of developing complete heart block. A safe and effective protocol has not been well established. Nineteen consecutive patients with 19 septal accessory pathways within the triangle of Koch underwent a protocol with power-titrated RF energy testing to identify the target site for successful catheter ablation. At every potential target site preselected by Local Electrogram characteristics, RF energy was started at 5 W for 10 seconds, with an increment of 5 W (duration remained at 10 s) until maximally 30 W or the observation of transient interruption of accessory pathway conduction. By this stepwise RF energy testing, we successfully Localized and ablated 18 (94.7%) of the 19 septal accessory pathways, 10 close to His bundle (zone I) and 8 away from it (zone II). The test-effective RF power was 20 W or less in 9 of all 11 septal accessory pathways in zone I, and 5 of the 8 in zone II (P = 0.68). Meanwhile, the final RF power for successful ablation was 30 W or less in 9 of the 10 zone I and 6 of the 8 zone II septal accessory pathways (P = 0.83). One patient with an accessory pathway in zone I was complicated with complete AV block after final ablation at 30 W. None of the Local Electrogram characteristics except continuous electrical activity during retrograde mapping was helpful in the prediction of ablation outcome. Careful RF energy titration testing could effectively help identify the target site for successful RF catheter ablation of septal accessory pathways within the triangle of Koch. The dependence on Local Electrogram manifestations could be frustrated by a low probability of success.
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value of Local Electrogram characteristics predicting successful catheter ablation of left versus right sided accessory atrioventricular pathways by radiofrequency current
The Cardiology, 1995Co-Authors: Jiunn Lee Lin, Jen Tsong Schie, Chuen Den Tseng, Wenjone Chen, Tin Fu Cheng, Shi Sheng Tsou, Jin Jer Chen, Yungzu Tseng, Wen Pin LienAbstract:Despite similar guidance by Local Electrogram criteria, catheter ablation of right-sided accessory atrioventricular (AV) pathways by radiofrequency current has been less effective than that of left-sided ones. In order to elucidate the possible diversities in Local electrosignal criteria, we systematically analyzed the morphological and timing characteristics of 215 bipolar Local Electrograms from catheter ablation sites of 65 left-sided accessory AV pathways and of 356 from those of 37 right-sided ones in 92 consecutive patients with Wolff-Parkinson-White syndrome or AV reentrant tachycardia incorporating concealed accessory AV pathways. After stepwise multivariate analysis, we selected the presence of a possible accessory pathway potential, Local ventricular activation preceding QRS complex for 20 ms or more during ventricular insertion mapping, and the Local retrograde ventriculoatrial (VA) continuity, Local retrograde VA interval ≤ 50 ms, Electrogram stability (left-sided targets only), retrograde accessory pathway potential (right-sided targets only) during atrial insertion mapping, as independent Local Electrogram predictors for successful ablation of left- and right-sided accessory AV pathways. Combination of all Local Electrogram predictors could have moderate chance of success (80 and 51 %) for the ventricular and atrial insertion ablation of left-sided accessory AV pathways, but only low probability of success (40% in ventricular insertion ablation) or very low sensitivity (12.5% in atrial insertion ablation) for right-sided ones. In conclusion, with the present approach, successful catheter ablation of right-sided accessory AV pathways, compared to left-sided ones, still necessitate a breakthrough in the precision mapping and the efficiency of energy delivery.