The Experts below are selected from a list of 1740 Experts worldwide ranked by ideXlab platform
David J Callans - One of the best experts on this subject based on the ideXlab platform.
-
association of septal late gadolinium enhancement on cardiac magnetic resonance with ventricular tachycardia ablation targets in Nonischemic Cardiomyopathy
Journal of Cardiovascular Electrophysiology, 2020Co-Authors: Pasquale Santangeli, David J Callans, David S Frankel, Erica S Zado, Ling Kuo, Jackson J Liang, Yuchi Han, Francis E MarchlinskiAbstract:BACKGROUND Ablation of septal substrate-associated ventricular tachycardia (VT) in patients with Nonischemic Cardiomyopathy (NICM) is challenging. We sought to standardize the characterization of septal substrates on late gadolinium enhancement (LGE) cardiac magnetic resonance (CMR) and to examine the association of that substrate with VT exit and isthmus sites on invasive mapping. METHODS LGE-CMR was performed before electroanatomic mapping and ablation for VT in 20 NICM patients. LGE extent and distribution were quantified using myocardial signal-intensity Z scores (SI-Z). The SI-Z thresholds correlating to previously validated voltage thresholds, for abnormal tissue and dense scar were defined. RESULTS Bipolar and unipolar (electrogram) voltage amplitude measurements from the LV and RV were negatively associated with SI-Z from LGE-CMR imaging (p < .05). SI-Z thresholds for appropriate CMR identification of septal substrates were determined to be greater than -.15 for border zone and greater than .03 for a dense scar. Among all patients, 34 critical VT sites were identified with SI-Z distribution in the range of -.97 to .06. Thirty (88.2%) critical sites were located in the dense LGE, 1 (2.9%) in the border zone, and 3 (8.9%) in healthy tissue but within 7 mm of LGE. Of note, critical VT sites were all located at the basal septum close to valves (distance to aortic valve: 17.5 ± 31.2 mm, mitral valve: 21.2 ± 8.7 mm) in nonsarcoidosis cases. CONCLUSIONS Critical sites of septal VT in NICM patients are predominantly in the CMR defined dense scar when using standardized signal-intensity thresholds.
-
association of scar distribution with epicardial electrograms and surface ventricular tachycardia qrs duration in Nonischemic Cardiomyopathy
Journal of Cardiovascular Electrophysiology, 2020Co-Authors: Jaeseok Park, Benoit Desjardins, Pasquale Santangeli, David S Frankel, Erica S Zado, Jackson J Liang, Tarek Zghaib, Shuanglun Xie, Irene Lucenapadros, David J CallansAbstract:INTRODUCTION The association of late gadolinium enhancement (LGE) on cardiac magnetic resonance (CMR) with epicardial and surface ventricular tachycardia (VT) electrogram features, in Nonischemic Cardiomyopathy (NICM), is unknown. We sought to define the association of LGE and viable wall thickness with epicardial electrogram features and exit site paced QRS duration in patients with NICM. METHODS A total of 19 patients (age 53.5 ± 11.5 years) with NICM (ejection fraction 40.2 ± 13.2%) underwent CMR before VT ablation. LGE transmurality was quantified on CMR and coregistered with 2294 endocardial and 2724 epicardial map points. RESULTS Both bipolar and unipolar voltage were associated with transmural signal intensity on CMR. Longer electrogram duration and fractionated potentials were associated with increased LGE transmurality, but late potentials or local abnormal ventricular activity were more prevalent in nontransmural versus transmural LGE regions (p < .05). Of all critical VT sites, 19% were located adjacent to regions with LGE but normal bipolar and unipolar voltage. Exit site QRS duration was affected by LGE transmurality and intramural scar location, but not by wall thickness, at the impulse origin. CONCLUSIONS In patients with NICM and VT, LGE is associated with epicardial electrogram features and may predict critical VT sites. Additionally, exit site QRS duration is affected by LGE transmurality and intramural location at the impulse origin or exit.
-
outcomes of simultaneous unipolar radiofrequency catheter ablation for intramural septal ventricular tachycardia in Nonischemic Cardiomyopathy
Heart Rhythm, 2019Co-Authors: Francis E Marchlinski, David J Callans, Fermin C Garcia, Yasuhiro Shirai, Daniele Muser, Jackson J Liang, Jiandu Yang, Pasquale SantangeliAbstract:Background Radiofrequency (RF) ablation of intramural septal ventricular tachycardia (VT) in patients with Nonischemic Cardiomyopathy (NICM) is challenging. Objective The purpose of this study was to investigate the outcomes of simultaneous unipolar RF ablation for intramural septal VT in NICM. Methods We included patients with NICM and mid-myocardial septal substrate referred for VT ablation. After failed prolonged sequential unipolar RF lesions, simultaneous unipolar RF was delivered using 2 open-irrigated catheters at the site of earliest activation and/or best entrainment or pace mapping and at an anatomically adjacent/opposite site (up to 40 W for up to 3 minutes; RF energy independently titrated for each catheter to achieve an impedance drop of at least 15% from the baseline values). Results A total of 6 patients (mean age 62±13 years; mean left ventricular ejection fraction 38%±17%) were included. The clinical VTs were mapped at the anterior interventricular septum in 2 (33%) patients and at the inferior septum in 4 (67%). In all patients, prolonged sequential unipolar RF at the best activation/entrainment/pace-mapping site and at an anatomically opposite/adjacent site failed to eliminate VT. In 3 cases (50%), late VT termination with VT reinducibility was observed after sequential unipolar RF. Simultaneous unipolar ablation was then delivered, resulting in VT elimination and noninducibility in all patients. No procedural complications and no steam pops were observed. After a median follow-up of 20 months (range 13–20 months), 4 patients (67%) remained free of VT recurrence. Conclusion In patients with NICM and intramural septal VT refractory to conventional RF ablation, simultaneous unipolar RF ablation is a safe and effective alternative ablation approach to improve long-term VT control.
-
scar progression in patients with Nonischemic Cardiomyopathy and ventricular arrhythmias
Heart Rhythm, 2014Co-Authors: Ioan Liuba, David J Callans, Sanjay Dixit, Fermin C Garcia, Mathew D Hutchinson, David Lin, Michael P Riley, David S Frankel, Gregory E Supple, Rupa BalaAbstract:BACKGROUND Disease progression in patients with Nonischemic Cardiomyopathy (NICM) is poorly understood. OBJECTIVE To assess left ventricular(LV) scar progression and dilatation by using endocardial electroanatomic mapping. METHODS We studied 13 patients with NICM and recurrent ventricular tachycardia. Two detailed sinus rhythm endocardial voltage maps(265 +/- 122 points/map) were obtained after a mean of 32 months(range 9-77 months). The scar area, defined by low bipolar (BI; less than 1.5 mV) and unipolar(UNI; less than 8.3 mV) endocardial voltage, and the LV volume were measured and compared. A scar difference of greater than 6% of the LV surface and an increase in LV volume of greater than= 20 mL were considered beyond measurement error. RESULTS Six (46%) patients had an increase in scar area beyond boundaries of prior ablation. Five patients had an increase in UNI and 1 patient had an increase in both BI and UNI areas. The increase in BI area represented 16% and the increase in UNI area represented 6.5%-46.2% of the LV surface. A significant decrease in LV ejection fraction was found only in patients with scar progression (from 39% +/- 8%:p = .0003) (LV volume increase ranging between 9% and 23%) was noted in 3 patients, all of whom had scar progression. CONCLUSIONS Progressive scarring with an increase in the area of UNI and less commonly BI electrogram abnormality is seen in 46% of the patients with NICM and ventricular tachycardia and is associated with LV dilatation and decrease in LV ejection fraction. The prominent UNI abnormality suggests predominantly midmyo-cardial or epicardial scarring.
-
characterization of trans septal activation during septal pacing criteria for identification of intramural ventricular tachycardia substrate in Nonischemic Cardiomyopathy
Circulation-arrhythmia and Electrophysiology, 2013Co-Authors: Brian P Betensky, Benoit Desjardins, David J Callans, Sanjay Dixit, Fermin C Garcia, Mathew D Hutchinson, Suraj Kapa, David S Frankel, Gregory E Supple, Erica S ZadoAbstract:Background— Identification of intramural basal-septal ventricular tachycardia (VT) substrate is challenging in Nonischemic Cardiomyopathy. We sought to (1) characterize normal/abnormal trans-septal right ventricular (RV) to left ventricular activation; (2) assess the effect of opposite RV pacing on left ventricular septal bipolar electrograms (EGMs); and (3) establish criteria for the identification of intramural septal VT substrate. Methods and Results— Endocardial activation mapping and local EGM assessment of the left interventricular septum was performed during RV basal septal pacing in 40 patients undergoing VT ablation with no evidence of septal scar (group 1, n=14) and with septal scar (group 2, n=26) defined by low septal unipolar voltage ( 40 ms (sensitivity 60%, specificity 100%; P 95 ms during pacing (sensitivity 22%, specificity 91%; P <0.001) identified septal scar (13/26 pts). Conclusions— In patients with Nonischemic Cardiomyopathy, VT and septal scar, delayed transmural conduction time (>40 ms) and fractionated, late, split, and wide (>95 ms) bipolar EGMs during RV basal pacing identify intramural VT substrate. In select cases, the basal septum appears compartmentalized as the stimulated wavefront is rerouted to the scar border.
Francis E Marchlinski - One of the best experts on this subject based on the ideXlab platform.
-
association of septal late gadolinium enhancement on cardiac magnetic resonance with ventricular tachycardia ablation targets in Nonischemic Cardiomyopathy
Journal of Cardiovascular Electrophysiology, 2020Co-Authors: Pasquale Santangeli, David J Callans, David S Frankel, Erica S Zado, Ling Kuo, Jackson J Liang, Yuchi Han, Francis E MarchlinskiAbstract:BACKGROUND Ablation of septal substrate-associated ventricular tachycardia (VT) in patients with Nonischemic Cardiomyopathy (NICM) is challenging. We sought to standardize the characterization of septal substrates on late gadolinium enhancement (LGE) cardiac magnetic resonance (CMR) and to examine the association of that substrate with VT exit and isthmus sites on invasive mapping. METHODS LGE-CMR was performed before electroanatomic mapping and ablation for VT in 20 NICM patients. LGE extent and distribution were quantified using myocardial signal-intensity Z scores (SI-Z). The SI-Z thresholds correlating to previously validated voltage thresholds, for abnormal tissue and dense scar were defined. RESULTS Bipolar and unipolar (electrogram) voltage amplitude measurements from the LV and RV were negatively associated with SI-Z from LGE-CMR imaging (p < .05). SI-Z thresholds for appropriate CMR identification of septal substrates were determined to be greater than -.15 for border zone and greater than .03 for a dense scar. Among all patients, 34 critical VT sites were identified with SI-Z distribution in the range of -.97 to .06. Thirty (88.2%) critical sites were located in the dense LGE, 1 (2.9%) in the border zone, and 3 (8.9%) in healthy tissue but within 7 mm of LGE. Of note, critical VT sites were all located at the basal septum close to valves (distance to aortic valve: 17.5 ± 31.2 mm, mitral valve: 21.2 ± 8.7 mm) in nonsarcoidosis cases. CONCLUSIONS Critical sites of septal VT in NICM patients are predominantly in the CMR defined dense scar when using standardized signal-intensity thresholds.
-
outcomes of simultaneous unipolar radiofrequency catheter ablation for intramural septal ventricular tachycardia in Nonischemic Cardiomyopathy
Heart Rhythm, 2019Co-Authors: Francis E Marchlinski, David J Callans, Fermin C Garcia, Yasuhiro Shirai, Daniele Muser, Jackson J Liang, Jiandu Yang, Pasquale SantangeliAbstract:Background Radiofrequency (RF) ablation of intramural septal ventricular tachycardia (VT) in patients with Nonischemic Cardiomyopathy (NICM) is challenging. Objective The purpose of this study was to investigate the outcomes of simultaneous unipolar RF ablation for intramural septal VT in NICM. Methods We included patients with NICM and mid-myocardial septal substrate referred for VT ablation. After failed prolonged sequential unipolar RF lesions, simultaneous unipolar RF was delivered using 2 open-irrigated catheters at the site of earliest activation and/or best entrainment or pace mapping and at an anatomically adjacent/opposite site (up to 40 W for up to 3 minutes; RF energy independently titrated for each catheter to achieve an impedance drop of at least 15% from the baseline values). Results A total of 6 patients (mean age 62±13 years; mean left ventricular ejection fraction 38%±17%) were included. The clinical VTs were mapped at the anterior interventricular septum in 2 (33%) patients and at the inferior septum in 4 (67%). In all patients, prolonged sequential unipolar RF at the best activation/entrainment/pace-mapping site and at an anatomically opposite/adjacent site failed to eliminate VT. In 3 cases (50%), late VT termination with VT reinducibility was observed after sequential unipolar RF. Simultaneous unipolar ablation was then delivered, resulting in VT elimination and noninducibility in all patients. No procedural complications and no steam pops were observed. After a median follow-up of 20 months (range 13–20 months), 4 patients (67%) remained free of VT recurrence. Conclusion In patients with NICM and intramural septal VT refractory to conventional RF ablation, simultaneous unipolar RF ablation is a safe and effective alternative ablation approach to improve long-term VT control.
-
ecg criteria to identify epicardial ventricular tachycardia in Nonischemic Cardiomyopathy
Circulation-arrhythmia and Electrophysiology, 2010Co-Authors: Ermengol Valles, Victor Bazan, Francis E MarchlinskiAbstract:Background— ECG criteria identifying epicardial (EPI) origin for ventricular tachycardia (VT) in Nonischemic Cardiomyopathy have not been determined. Endocardial (ENDO) and EPI basal left ventricle fibrosis characterizes the VT substrate. Methods and Results— We assessed the QRS from 102 basal-superior/lateral EPI and 67 comparable ENDO pace maps in 14 patients with Nonischemic Cardiomyopathy. Pace mapping focused on low bipolar voltage areas. Published morphology criteria: q wave in lead I (QWLI) and no q waves in inferior leads and interval criteria: pseudo-delta wave ≥34 ms, intrinsicoid deflection time ≥85 ms, shortest RS complex ≥121 ms, and maximum deflection index ≥0.55 were assessed for ability to identify EPI origin. Sixteen EPI and 8 ENDO of the 34 mapped VTs (71%) in the study population and 14 EPI and 7 ENDO VTs from an 11-patient validation cohort were localized to basal-superior/lateral left ventricle and corroborated pacing data. A QWL1 was seen in EPI but not ENDO pace maps (91% versus 4%; P <0.001), identified 14 of 16 EPI VTs (sensitivity, 88%), and was seen in 1 of 8 ENDO VTs (specificity, 88%). None of the remaining criteria achieved similar sensitivity without specificity <50%. We identified 4 criteria (q waves in inferior leads, pseudo-delta wave ≥75 ms, maximum deflection index ≥0.59, and QWL1) having ≥95% specificity and ≥20% sensitivity in identifying EPI/ENDO origin for pace maps. This 4-step algorithm identified the origin in 109 of 115 pace maps (95%), 21 of 24 VTs (88%) in the study population, and 19 of 21 VTs (90%) in validation cohort. Conclusions— Morphological ECG features that describe the initial QRS vector can help identify basal-superior/lateral EPI VTs in Nonischemic Cardiomyopathy. Received February 22, 2009; accepted December 3, 2009.
-
perivalvular fibrosis and monomorphic ventricular tachycardia toward a unifying hypothesis in Nonischemic Cardiomyopathy
Circulation, 2007Co-Authors: Francis E MarchlinskiAbstract:The basis for arrhythmogenesis in patients with Nonischemic Cardiomyopathy and ventricular tachycardia (VT) needs further elucidation. Cardiac arrest and/or nonsustained VT are common arrhythmia presentations in the setting of Nonischemic Cardiomyopathy, with sustained monomorphic VT being relatively uncommon.1,2 Importantly, bundle-branch reentrant VT is identified as the VT mechanism in a significant percentage of patients with monomorphic VT in the setting of Nonischemic Cardiomyopathy.3,4 However, even in patients with Nonischemic left ventricular (LV) or right ventricular (RV) Cardiomyopathy, the majority of VT appears to originate from the myocardium and is not due to bundle-branch reentry.4–11 Detailed substrate, activation, and entrainment mapping has begun to provide some valuable clues related to the mechanism and pathophysiology of scar-based VT in the setting of Nonischemic Cardiomyopathy resulting from a variety of causes.4–11 Although not focusing on VT after valve surgery, these data have been helpful in identifying likely regions of origin for VT and facilitating ablative therapy in other Nonischemic settings. Article p 2005 When dealing with uncommon disease processes, one looks to centers with sizable clinical experience to review their results and provide important insight. In this issue of Circulation , the report by Eckart and colleagues12 answers that charge. Six years of clinical experience with VT ablation resulted in the identification of 20 patients who developed VT after prior cardiac valve surgery and underwent catheter ablative therapy. Importantly, most of the patients demonstrated mildly to moderately depressed LV function with a median LV ejection fraction of 45%. Characterization of the substrate, mechanism, and outcome of ablative therapy provides important insight in terms of pathogenesis. Such detailed information should be compared with findings at the time of VT ablation in a variety of other Nonischemic cardiomyopathies to attempt to identify common and potentially important pathophysiological links.4–11 Indeed, …
-
characterization of endocardial electrophysiological substrate in patients with Nonischemic Cardiomyopathy and monomorphic ventricular tachycardia
Circulation, 2003Co-Authors: Henry H Hsia, David J Callans, Francis E MarchlinskiAbstract:Background— Although catheter mapping has been used to define the endocardial electrogram characteristics in patients with ventricular tachycardia (VT) and coronary disease, characterization of the electrophysiological substrate in patients with VT and Nonischemic Cardiomyopathy is limited. Methods and Results— Left ventricular endocardial electroanatomical mapping was performed in 19 patients with Nonischemic Cardiomyopathy and monomorphic VT with an average of 178±83 sites per chamber mapped. Abnormal bipolar electrogram was defined as endocardial voltage signal amplitude of <1.8 mV. The extent and location of abnormal endocardium was estimated by measuring areas of abnormal electrogram recordings from 3D voltage maps. The origin of VT was approximated by identifying sites of entrainment with concealed fusion or early presystolic activity and/or by pace mapping. Abnormal electrograms were recorded over a 41±28 cm2 area that represented 20±12% of total endocardial surface. The majority of patients (14/19...
Erica S Zado - One of the best experts on this subject based on the ideXlab platform.
-
association of septal late gadolinium enhancement on cardiac magnetic resonance with ventricular tachycardia ablation targets in Nonischemic Cardiomyopathy
Journal of Cardiovascular Electrophysiology, 2020Co-Authors: Pasquale Santangeli, David J Callans, David S Frankel, Erica S Zado, Ling Kuo, Jackson J Liang, Yuchi Han, Francis E MarchlinskiAbstract:BACKGROUND Ablation of septal substrate-associated ventricular tachycardia (VT) in patients with Nonischemic Cardiomyopathy (NICM) is challenging. We sought to standardize the characterization of septal substrates on late gadolinium enhancement (LGE) cardiac magnetic resonance (CMR) and to examine the association of that substrate with VT exit and isthmus sites on invasive mapping. METHODS LGE-CMR was performed before electroanatomic mapping and ablation for VT in 20 NICM patients. LGE extent and distribution were quantified using myocardial signal-intensity Z scores (SI-Z). The SI-Z thresholds correlating to previously validated voltage thresholds, for abnormal tissue and dense scar were defined. RESULTS Bipolar and unipolar (electrogram) voltage amplitude measurements from the LV and RV were negatively associated with SI-Z from LGE-CMR imaging (p < .05). SI-Z thresholds for appropriate CMR identification of septal substrates were determined to be greater than -.15 for border zone and greater than .03 for a dense scar. Among all patients, 34 critical VT sites were identified with SI-Z distribution in the range of -.97 to .06. Thirty (88.2%) critical sites were located in the dense LGE, 1 (2.9%) in the border zone, and 3 (8.9%) in healthy tissue but within 7 mm of LGE. Of note, critical VT sites were all located at the basal septum close to valves (distance to aortic valve: 17.5 ± 31.2 mm, mitral valve: 21.2 ± 8.7 mm) in nonsarcoidosis cases. CONCLUSIONS Critical sites of septal VT in NICM patients are predominantly in the CMR defined dense scar when using standardized signal-intensity thresholds.
-
association of scar distribution with epicardial electrograms and surface ventricular tachycardia qrs duration in Nonischemic Cardiomyopathy
Journal of Cardiovascular Electrophysiology, 2020Co-Authors: Jaeseok Park, Benoit Desjardins, Pasquale Santangeli, David S Frankel, Erica S Zado, Jackson J Liang, Tarek Zghaib, Shuanglun Xie, Irene Lucenapadros, David J CallansAbstract:INTRODUCTION The association of late gadolinium enhancement (LGE) on cardiac magnetic resonance (CMR) with epicardial and surface ventricular tachycardia (VT) electrogram features, in Nonischemic Cardiomyopathy (NICM), is unknown. We sought to define the association of LGE and viable wall thickness with epicardial electrogram features and exit site paced QRS duration in patients with NICM. METHODS A total of 19 patients (age 53.5 ± 11.5 years) with NICM (ejection fraction 40.2 ± 13.2%) underwent CMR before VT ablation. LGE transmurality was quantified on CMR and coregistered with 2294 endocardial and 2724 epicardial map points. RESULTS Both bipolar and unipolar voltage were associated with transmural signal intensity on CMR. Longer electrogram duration and fractionated potentials were associated with increased LGE transmurality, but late potentials or local abnormal ventricular activity were more prevalent in nontransmural versus transmural LGE regions (p < .05). Of all critical VT sites, 19% were located adjacent to regions with LGE but normal bipolar and unipolar voltage. Exit site QRS duration was affected by LGE transmurality and intramural scar location, but not by wall thickness, at the impulse origin. CONCLUSIONS In patients with NICM and VT, LGE is associated with epicardial electrogram features and may predict critical VT sites. Additionally, exit site QRS duration is affected by LGE transmurality and intramural location at the impulse origin or exit.
-
characterization of trans septal activation during septal pacing criteria for identification of intramural ventricular tachycardia substrate in Nonischemic Cardiomyopathy
Circulation-arrhythmia and Electrophysiology, 2013Co-Authors: Brian P Betensky, Benoit Desjardins, David J Callans, Sanjay Dixit, Fermin C Garcia, Mathew D Hutchinson, Suraj Kapa, David S Frankel, Gregory E Supple, Erica S ZadoAbstract:Background— Identification of intramural basal-septal ventricular tachycardia (VT) substrate is challenging in Nonischemic Cardiomyopathy. We sought to (1) characterize normal/abnormal trans-septal right ventricular (RV) to left ventricular activation; (2) assess the effect of opposite RV pacing on left ventricular septal bipolar electrograms (EGMs); and (3) establish criteria for the identification of intramural septal VT substrate. Methods and Results— Endocardial activation mapping and local EGM assessment of the left interventricular septum was performed during RV basal septal pacing in 40 patients undergoing VT ablation with no evidence of septal scar (group 1, n=14) and with septal scar (group 2, n=26) defined by low septal unipolar voltage ( 40 ms (sensitivity 60%, specificity 100%; P 95 ms during pacing (sensitivity 22%, specificity 91%; P <0.001) identified septal scar (13/26 pts). Conclusions— In patients with Nonischemic Cardiomyopathy, VT and septal scar, delayed transmural conduction time (>40 ms) and fractionated, late, split, and wide (>95 ms) bipolar EGMs during RV basal pacing identify intramural VT substrate. In select cases, the basal septum appears compartmentalized as the stimulated wavefront is rerouted to the scar border.
-
sinus rhythm ecg criteria associated with basal lateral ventricular tachycardia substrate in patients with Nonischemic Cardiomyopathy
Journal of Cardiovascular Electrophysiology, 2011Co-Authors: Wendy S Tzou, Rupa Bala, David J Callans, Sanjay Dixit, Fermin C Garcia, Mathew D Hutchinson, David Lin, Erica S Zado, Joshua M Cooper, Michael P RileyAbstract:ECG Criteria Associated with NICM VT. Introduction: Patients with Nonischemic Cardiomyopathy (NICM) and ventricular tachycardia (VT) usually have basal-lateral scar in the left ventricle (LV). We sought to determine electrocardiogram (ECG) characteristics that may help identify NICM patients with basal-lateral scar and VT. Methods and Results: Phase I, study patients (n = 25) had NICM, VT, and endocardial/epicardial basal-lateral LV low voltage consistent with scar on detailed mapping. ECGs were compared to controls (n = 18) with NICM, and comparable age and gender without VT/known scar. All patients had either sinus or paced atrial rhythm ECGs without bundle-branch block or ventricular pacing. In phase II, criteria were evaluated prospectively, blinded to clinical data, using ECGs from 15 NICM patients, of which 7 patients had VT and endocardial/epicardial basal-lateral LV scar on detailed mapping. Of ECG characteristics studied, V1 R and R:S ratio, and V6 S and S:R ratio were univariately associated with basal-lateral-scar associated VT. Controlling for LVEF and multicollinearity in multivariate analyses, V1 R ≥ 0.15 mV (P = 0.001) and V6 S ≥ 0.15 mV (P < 0.001), or V6 S:R ≥ 0.2 mV (P < 0.001), best predicted presence of basal-lateral scar. In Phase II, the former criteria best identified those with NICM and VT because of basal-lateral scar, with sensitivity and specificity 0.86 and 0.88, respectively. Conclusions: Among patients with NICM, VT, and normal QRS duration, V1 R ≥ 0.15 mV and V6 S ≥ 0.15 mV predicted presence of basal-lateral LV areas of bipolar low voltage. This ECG information may have important value in defining presence of LV scar and possible risk for VT in NICM patients. (J Cardiovasc Electrophysiol, Vol. 22, pp. 1351-1358, December 2011)
-
electroanatomic substrate and ablation outcome for suspected epicardial ventricular tachycardia in left ventricular Nonischemic Cardiomyopathy
Journal of the American College of Cardiology, 2009Co-Authors: Oscar Cano, Rupa Bala, Fermin C Garcia, Mathew D Hutchinson, Michael Riley, David Lin, Erica S Zado, Joshua M Cooper, Sanjay DixitAbstract:Objectives The aim of the study was to define the epicardial substrate and ablation outcome in patients with left ventricular Nonischemic Cardiomyopathy (NICM) and suspected epicardial ventricular tachycardia (VT). Background Ventricular tachycardia in NICM often originates from the epicardium. Methods Twenty-two patients with NICM underwent detailed endocardial and epicardial bipolar voltage maps and VT ablation for suspected epicardial VT. Eight patients with normal hearts and idiopathic VT served to define normal epicardial electrograms. Low-voltage regions were also assessed for wide (>80 ms), split, or late electrograms. Results Normal epicardial bipolar voltage was identified as >1.0 mV on the basis of the reference population. Confluent low-voltage areas were present in 18 epicardial (82%) and 12 endocardial (54%) maps and were typically over basal lateral LV. In the 18 patients with epicardial VT on the basis of activation/pacemapping, the mean epicardial area was greater than the endocardial low-voltage area (55.3 ± 33.5 cm2vs. 22.9 ± 32.4 cm2, p 80 ms), split, and/or late electrograms rarely seen in the reference patients (2.3%). During follow-up of 18 ± 7 months, ablation resulted in VT elimination in 15 of 21 patients (71%) including 14 of 18 patients (78%) with epicardial VT. Conclusions In patients with NICM and VT of epicardial origin, the substrate is characterized by areas of basal LV epicardial > endocardial bipolar low voltage. The electrograms in these areas are not only small ( 80 ms), split, and/or late, and help identify the substrate targeted for successful ablation.
Roderick Tung - One of the best experts on this subject based on the ideXlab platform.
-
prognostic value of cardiac magnetic resonance septal late gadolinium enhancement patterns for periaortic ventricular tachycardia ablation heterogeneity of the anteroseptal substrate in Nonischemic Cardiomyopathy
Heart Rhythm, 2021Co-Authors: Takuro Nishimura, Gaurav A Upadhyay, Hena Patel, Shuo Wang, Heather L Smith, Cevher Ozcan, Dalise Y Shatz, Hemal M Nayak, Amit R Patel, Roderick TungAbstract:Background Ventricular tachycardia (VT) from the anteroseptal subtype of Nonischemic Cardiomyopathy has a high probability of recurrence after catheter ablation. Objective The purpose of this study was to determine the predictive value of septal scar patterns by late gadolinium enhancement (LGE) cardiac magnetic resonance (CMR) on ablation outcomes in patients with VT arising from an anteroseptal substrate. Methods Patients with periaortic VT arising from an anteroseptal substrate with preprocedural wideband LGE-CMR were divided into 2 groups by the degree of longitudinal septal LGE extension as full-length septal (≥80% anteroposterior length) or partial septal ( Results Among 234 patients referred for scar-related VT ablation between 2017 and 2020, 25 patients (92% male; age 64 ± 8 years) and a total of 108 VTs were analyzed. A greater number of VT morphologies were induced in patients with full-length septal LGE compared to partial septal LGE (median [interquartile range]: 5 [3–9] vs 2 [1–4]; P = .005). Patients with VT recurrence had larger septal LGE volumes compared to those without recurrence (11.4 mL [8.8–13.9] vs 4.2 mL [0–9.5]; P = .012). At median follow-up of 16 months (5–22), overall freedom from VT recurrence was 52% and significantly higher in patients with partial septal LGE than in those with full-length septal LGE (80% vs 20%; P = .005). Conclusion VT originating from an anteroseptal substrate is associated with heterogeneous patterns and extent of CMR septal scar. Preprocedural imaging may substratify this challenging patient population for the propensity for multiple induced VT morphologies and recurrence after catheter ablation.
-
cardiac resynchronization therapy in patients with Nonischemic Cardiomyopathy using left bundle branch pacing
JACC: Clinical Electrophysiology, 2020Co-Authors: Weijian Huang, Kenneth A Ellenbogen, Pugazhendhi Vijayaraman, Xueying Chen, Bingni Cai, Jiangang Zou, Rongfang Lan, Guangyun Mao, Zachary I Whinnett, Roderick TungAbstract:Abstract Objectives The aim of this study was to assess the feasibility and efficacy of left bundle branch pacing (LBBP) using a novel intraseptal technique to deliver cardiac resynchronization therapy (CRT) in patients with left bundle branch block (LBBB) and Nonischemic Cardiomyopathy. Background His bundle pacing to correct LBBB is a viable alternative approach to achieve CRT but is limited by suboptimal lead delivery and high thresholds. Methods This was a prospective, multicenter study performed between June 2017 and August 2018 at 6 centers. Patients with Nonischemic Cardiomyopathy, complete LBBB, and left ventricular ejection fractions (LVEFs) ≤50% who had indications for CRT and/or ventricular pacing in whom LBBP was attempted were included. Success rates, QRS duration, LVEF, left ventricular end-systolic volume, and improvement in functional class were assessed. Results LBBP was successful in 61 of 63 patients (97%, mean age 68 ± 11 years, 52.4% men). During LBBP, QRS duration narrowed from 169 ± 16 to 118 ± 12 ms (p Conclusions LBBP is a feasible and effective method for achieving electric resynchronization of LBBB, with resultant improvements in left ventricular structure and function. Low and stable pacing thresholds may be advantageous over His bundle pacing for CRT in patients with LBBB and Nonischemic Cardiomyopathy.
-
characterization of the arrhythmogenic substrate in ischemic and Nonischemic Cardiomyopathy implications for catheter ablation of hemodynamically unstable ventricular tachycardia
Journal of the American College of Cardiology, 2010Co-Authors: Shiro Nakahara, Roderick Tung, Rafael Ramirez, Yoav Michowitz, Marmar Vaseghi, Eric Buch, Jean Gima, Isaac Wiener, Aman Mahajan, Noel G BoyleAbstract:Catheter ablation of hemodynamically unstable ventricular tachycardia (VT) relies on substrate mapping of sites critical for reentry. Late potentials (LP), commonly seen in post-infarction scars, reflect areas of myocardium where conduction is slowed and interrupted by fibrosis (1,2). Although LPs are not specific for critical isthmuses, they are highly sensitive as a guide for targeting ablation in patients with ischemic Cardiomyopathy (ICM) (3–5). The prevalence and value of LPs as ablation targets in patients with Nonischemic Cardiomyopathy (NICM) remains unknown. Analysis of human explanted hearts with dilated Cardiomyopathy has revealed fibrosis, myocyte disarray, and membrane abnormalities.(6,7) Fractionated electrograms in patients with NICM have been attributed to lines of activation block from fibrosis, resulting in nonuniform conduction.(8) However, scar in NICM differs from infarct scar with less confluence, a basal predilection, and less endocardial involvement.(9–11) The purpose of this study was to compare the characteristics and prevalence of LPs within scar tissue in patients with NICM and ICM and to assess their value as ablation targets.
Pasquale Santangeli - One of the best experts on this subject based on the ideXlab platform.
-
association of septal late gadolinium enhancement on cardiac magnetic resonance with ventricular tachycardia ablation targets in Nonischemic Cardiomyopathy
Journal of Cardiovascular Electrophysiology, 2020Co-Authors: Pasquale Santangeli, David J Callans, David S Frankel, Erica S Zado, Ling Kuo, Jackson J Liang, Yuchi Han, Francis E MarchlinskiAbstract:BACKGROUND Ablation of septal substrate-associated ventricular tachycardia (VT) in patients with Nonischemic Cardiomyopathy (NICM) is challenging. We sought to standardize the characterization of septal substrates on late gadolinium enhancement (LGE) cardiac magnetic resonance (CMR) and to examine the association of that substrate with VT exit and isthmus sites on invasive mapping. METHODS LGE-CMR was performed before electroanatomic mapping and ablation for VT in 20 NICM patients. LGE extent and distribution were quantified using myocardial signal-intensity Z scores (SI-Z). The SI-Z thresholds correlating to previously validated voltage thresholds, for abnormal tissue and dense scar were defined. RESULTS Bipolar and unipolar (electrogram) voltage amplitude measurements from the LV and RV were negatively associated with SI-Z from LGE-CMR imaging (p < .05). SI-Z thresholds for appropriate CMR identification of septal substrates were determined to be greater than -.15 for border zone and greater than .03 for a dense scar. Among all patients, 34 critical VT sites were identified with SI-Z distribution in the range of -.97 to .06. Thirty (88.2%) critical sites were located in the dense LGE, 1 (2.9%) in the border zone, and 3 (8.9%) in healthy tissue but within 7 mm of LGE. Of note, critical VT sites were all located at the basal septum close to valves (distance to aortic valve: 17.5 ± 31.2 mm, mitral valve: 21.2 ± 8.7 mm) in nonsarcoidosis cases. CONCLUSIONS Critical sites of septal VT in NICM patients are predominantly in the CMR defined dense scar when using standardized signal-intensity thresholds.
-
association of scar distribution with epicardial electrograms and surface ventricular tachycardia qrs duration in Nonischemic Cardiomyopathy
Journal of Cardiovascular Electrophysiology, 2020Co-Authors: Jaeseok Park, Benoit Desjardins, Pasquale Santangeli, David S Frankel, Erica S Zado, Jackson J Liang, Tarek Zghaib, Shuanglun Xie, Irene Lucenapadros, David J CallansAbstract:INTRODUCTION The association of late gadolinium enhancement (LGE) on cardiac magnetic resonance (CMR) with epicardial and surface ventricular tachycardia (VT) electrogram features, in Nonischemic Cardiomyopathy (NICM), is unknown. We sought to define the association of LGE and viable wall thickness with epicardial electrogram features and exit site paced QRS duration in patients with NICM. METHODS A total of 19 patients (age 53.5 ± 11.5 years) with NICM (ejection fraction 40.2 ± 13.2%) underwent CMR before VT ablation. LGE transmurality was quantified on CMR and coregistered with 2294 endocardial and 2724 epicardial map points. RESULTS Both bipolar and unipolar voltage were associated with transmural signal intensity on CMR. Longer electrogram duration and fractionated potentials were associated with increased LGE transmurality, but late potentials or local abnormal ventricular activity were more prevalent in nontransmural versus transmural LGE regions (p < .05). Of all critical VT sites, 19% were located adjacent to regions with LGE but normal bipolar and unipolar voltage. Exit site QRS duration was affected by LGE transmurality and intramural scar location, but not by wall thickness, at the impulse origin. CONCLUSIONS In patients with NICM and VT, LGE is associated with epicardial electrogram features and may predict critical VT sites. Additionally, exit site QRS duration is affected by LGE transmurality and intramural location at the impulse origin or exit.
-
comparison of the arrhythmogenic substrate between men and women with Nonischemic Cardiomyopathy
Heart Rhythm, 2019Co-Authors: Pasquale Santangeli, Gregory E Supple, Ling Kuo, Yasuhiro Shirai, Daniele Muser, Jackson J Liang, Simon A Castro, Robert D Schaller, David LinAbstract:Background Outcomes of ventricular tachycardia (VT) ablation in structural heart disease have been reported to differ by sex. Whether this is due to differences in the underlying arrhythmogenic substrates among patients with Nonischemic Cardiomyopathy (NICM) remains unclear. Objective The purpose of this study was to compare the characteristics of arrhythmogenic substrates between women and men with NICM. Methods We analyzed 160 consecutive patients (26 women) with NICM who were undergoing VT ablation at the Hospital of the University of Pennsylvania. Of these 160 patients, 59 (13 women) underwent cardiac magnetic resonance (CMR) before the ablation procedure. The arrhythmogenic substrate was analyzed qualitatively and quantitatively by CMR and/or detailed electroanatomic mapping. Results There were no significant differences in left ventricular scar percentage as defined by CMR (9.5% ± 7.8% in women vs 11.2% ± 8.6% in men; P = .5), endocardial bipolar voltage ( Conclusion Scar percentage, transmurality, and distribution are similar between women and men with NICM.
-
outcomes of simultaneous unipolar radiofrequency catheter ablation for intramural septal ventricular tachycardia in Nonischemic Cardiomyopathy
Heart Rhythm, 2019Co-Authors: Francis E Marchlinski, David J Callans, Fermin C Garcia, Yasuhiro Shirai, Daniele Muser, Jackson J Liang, Jiandu Yang, Pasquale SantangeliAbstract:Background Radiofrequency (RF) ablation of intramural septal ventricular tachycardia (VT) in patients with Nonischemic Cardiomyopathy (NICM) is challenging. Objective The purpose of this study was to investigate the outcomes of simultaneous unipolar RF ablation for intramural septal VT in NICM. Methods We included patients with NICM and mid-myocardial septal substrate referred for VT ablation. After failed prolonged sequential unipolar RF lesions, simultaneous unipolar RF was delivered using 2 open-irrigated catheters at the site of earliest activation and/or best entrainment or pace mapping and at an anatomically adjacent/opposite site (up to 40 W for up to 3 minutes; RF energy independently titrated for each catheter to achieve an impedance drop of at least 15% from the baseline values). Results A total of 6 patients (mean age 62±13 years; mean left ventricular ejection fraction 38%±17%) were included. The clinical VTs were mapped at the anterior interventricular septum in 2 (33%) patients and at the inferior septum in 4 (67%). In all patients, prolonged sequential unipolar RF at the best activation/entrainment/pace-mapping site and at an anatomically opposite/adjacent site failed to eliminate VT. In 3 cases (50%), late VT termination with VT reinducibility was observed after sequential unipolar RF. Simultaneous unipolar ablation was then delivered, resulting in VT elimination and noninducibility in all patients. No procedural complications and no steam pops were observed. After a median follow-up of 20 months (range 13–20 months), 4 patients (67%) remained free of VT recurrence. Conclusion In patients with NICM and intramural septal VT refractory to conventional RF ablation, simultaneous unipolar RF ablation is a safe and effective alternative ablation approach to improve long-term VT control.
-
scar homogenization versus limited substrate ablation in patients with Nonischemic Cardiomyopathy and ventricular tachycardia
Journal of the American College of Cardiology, 2016Co-Authors: Yalci Gokogla, Sanghamitra Mohanty, Carola Gianni, Pasquale Santangeli, Chinta Trivedi, Mahmu F Gunes, Ami Alahmad, Joseph G Gallinghouse, Rodney Horto, Patrick HranitzkyAbstract:Abstract Background Scar homogenization improves long-term ventricular arrhythmia–free survival compared with standard limited-substrate ablation in patients with post-infarction ventricular tachycardia (VT). Whether such benefit extends to patients with Nonischemic Cardiomyopathy and scar-related VT is unclear. Objectives The aim of this study was to assess the long-term efficacy of an endoepicardial scar homogenization approach compared with standard ablation in this population. Methods Consecutive patients with dilated Nonischemic Cardiomyopathy (n = 93), scar-related VTs, and evidence of low-voltage regions on the basis of pre-defined criteria on electroanatomic mapping (i.e., bipolar voltage Results Acute procedural success rates were 69.4% and 42.1% after scar homogenization and standard ablation, respectively (p = 0.01). During a mean follow-up period of 14 ± 2 months, single-procedure success rates were 63.9% after scar homogenization and 38.6% after standard ablation (p = 0.031). After multivariate analysis, scar homogenization and left ventricular ejection fraction were predictors of long-term success. During follow-up, the rehospitalization rate was significantly lower in the scar homogenization group (p = 0.035). Conclusions In patients with dilated Nonischemic Cardiomyopathy, scar-related VT, and evidence of low-voltage regions on electroanatomic mapping, endoepicardial homogenization of the scar significantly increased freedom from any recurrent ventricular arrhythmia compared with a standard limited-substrate ablation. However, the success rate with this approach appeared to be lower than previously reported with ischemic Cardiomyopathy, presumably because of the septal and midmyocardial distribution of the scar in some patients.
