3692 A novel algorithm for determining endocardial ventricular tachycardia exit site location from surface 12-lead electrocardiogram morphology in human, infarct related ventricular tachycardia

Verapamil-sensitive fascicular ventricular tachycardia (VT) is the most common form of idiopathic left VT. According to the QRS morphology and the successful ablation site, left fascicular VT can be classified into three subgroups: left posterior fascicular VT, whose QRS morphology shows right bundle branch block (RBBB) configuration and superior axis (common form); left anterior fascicular VT, whose QRS morphology shows RBBB configuration and right-axis deviation (uncommon form), and upper septal fascicular VT, whose QRS morphology shows narrow QRS configuration and normal or right-axis deviation (rare form). Posterior and anterior fascicular VT can be successfully ablated at the posterior or anterior mid-septum with a diastolic Purkinje potential during VT or at the VT exit site with a fused pre-systolic Purkinje potential. Upper septal fascicular VT can also be ablated at the site with diastolic Purkinje potential at the upper septum. Recognition of the heterogeneity of this VT and its unique characteristics should facilitate appropriate diagnosis and therapy.

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Abstract 16187: Validation of Novel Algorithm to Automate Detection of Fractionated Electrograms During Ventricular Tachycardia (VT) Ablation

Circulation ◽

10.1161/circ.132.suppl_3.16187 ◽

2015 ◽

Vol 132 (suppl_3) ◽

Author(s):

Pouria Alipour ◽

Yaariv Khaykin ◽

Meysam Pirbaglou ◽

Paul Ritvo ◽

Gal Hayam ◽

...

Keyword(s):

Ventricular Tachycardia ◽

Area Under The Curve ◽

High Sensitivity ◽

Left Ventricular ◽

Target Area ◽

Automate Detection ◽

Noise Threshold ◽

Vt Ablation ◽

Patient At Risk ◽

Novel Algorithm

Introduction: Ablation of ventricular tachycardia (VT) substrate in patient at risk for VT in the setting of ischemic heart disease is a technically challenging procedure. We thought to evaluate a novel algorithm used to automatically identify target electrograms. Methods: 16 consecutive patients (70±10 years of age, 90% male, 34±18% LV EF) had 20 ablations for ischemic VT using CARTO 3 mapping system over 2 years. Left ventricular (LV) substrate was mapped during right ventricular (RV) apical stimulation. Navistar Thermocool 3.5 mm irrigated tip catheters were used in all patients. A novel algorithm counting the number of electrogram deflections (NOD) crossing the 0.05mV noise threshold and duration of time from first to last such deflection during the window of interest (total fractionation time, TFT) was applied to all acquired maps after ablation was complete. Snapshots of 200 electrograms representing the high and low end of TFT and NOD values were presented to a group of 8 electrophysiologists experienced in VT ablation who were asked to select electrograms they would target for substrate ablation. The diagnostic accuracy of TFT and NOD values was then analysed. Results: Across the range of TFT values (0.0-281.0 ms), a cut-off value of 49.0 ms (81.6% sensitivity, 57% specificity) was established as an optimal indicator of an ablation target. Area under the curve for TFT was 0.675 (95% CI: 0.59-0.75, p=0.001). For NOD values (0.0-70.0 deflections), a cut off of 4.5 deflections (88.0% Sensitivity, 57 % specificity) was established as an optimal indicator of an ablation target. The area under the curve for NOD yielded an area of 0.75 (95% CI: 0.68-0.82, P=0.001). For TFT-NOD product as a variable, a cut-off value of 64 (91.0% Sensitivity, 52.4 % specificity) an optimal indicator of an ablation target. The Area under the curve for NOD and TFT multiple was 0.72 (95% CI: 0.65-0.80, P=0.001). Conclusion: A novel algorithm may be able to automatically classify LV substrate during mapping and ablation of ischemic VT with high sensitivity and acceptable specificity.

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Comparative Analysis of Two-Piece Extended Peritoneal Dialysis Catheters with Remote Exit-Site Locations and Conventional Abdominal Catheters

Peritoneal Dialysis International ◽

10.3747/pdi.2009.00004 ◽

2010 ◽

Vol 30 (1) ◽

pp. 46-55 ◽

Cited By ~ 17

Author(s):

John H. Crabtree ◽

Raoul J. Burchette

Keyword(s):

Poisson Regression ◽

Coagulase Negative Staphylococcus ◽

Site Location ◽

Exit Site ◽

Exit Site Infection ◽

Catheter Survival ◽

Patient Demographics ◽

Kaplan Meier ◽

Included Patient ◽

Upper Abdomen

BackgroundAn alternative peritoneal catheter exit-site location is sometimes needed in patients with obesity, floppy skin folds, intestinal stomas, urinary and fecal incontinence, and chronic yeast intertrigo. Two-piece extended catheters permit remote exit-site locations away from problematic abdominal conditions.ObjectiveThe effect on clinical outcomes by remotely locating catheter exit sites to the upper abdomen or chest was compared to conventional lower abdominal sites.MethodsIn a nonrandomized design, peritoneal access was established with 158 extended catheters and 270 conventional catheters based upon body habitus and special clinical needs. Prospective data collection included patient demographics, infectious and mechanical complications, and catheter survival.ResultsKaplan–Meier survival time until first exit-site infection was longer for extended catheters ( p = 0.03). Poisson regression showed no difference in exit site, subcutaneous tunnel, and peritonitis infection rates; however, the proportion of catheters lost during peritonitis episodes was significantly greater for extended catheters ( p = 0.007) and appeared to be due primarily to coagulase-negative staphylococcus organisms. Poisson regression showed interactions of body mass index (BMI) and diabetic status in determining catheter loss from peritonitis for both catheter types ( p = 0.02). Extended catheter patients had higher BMI and diabetes prevalence ( p < 0.0001). Overall extended catheter survival at 1, 2, and 3 years (92%, 80%, 71%) trended lower than conventional devices (93%, 87%, 80%; p = 0.0505).ConclusionsExtended catheters enable peritoneal access for patients in whom conventional catheter placement would be difficult or impossible. Certain patient and extended-catheter characteristics may contribute to loss from peritonitis.

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A Prospective Study on the Risk-Stratification for Patients With Non-Sustained Ventricular Tachycardia Using a Novel Algorithm

Circulation Journal ◽

10.1253/circj.71.1107 ◽

2007 ◽

Vol 71 (7) ◽

pp. 1107-1114 ◽

Cited By ~ 4

Author(s):

Akira Ueno ◽

Yoshinori Kobayashi ◽

Kenji Yodogawa ◽

Yasushi Miyauchi ◽

Toshimi Yajima ◽

...

Keyword(s):

Ventricular Tachycardia ◽

Risk Stratification ◽

Prospective Study ◽

Sustained Ventricular Tachycardia ◽

A Prospective Study ◽

Novel Algorithm

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Automatic Supporting System for Regionalization of Ventricular Tachycardia Exit Site in Implantable Defibrillators

PLoS ONE ◽

10.1371/journal.pone.0124514 ◽

2015 ◽

Vol 10 (4) ◽

pp. e0124514

Author(s):

Margarita Sanromán-Junquera ◽

Inmaculada Mora-Jiménez ◽

Jesús Almendral ◽

Arcadio García-Alberola ◽

José Luis Rojo-Álvarez

Keyword(s):

Ventricular Tachycardia ◽

Implantable Defibrillators ◽

Exit Site ◽

Supporting System

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Localization of Ventricular Tachycardia Exit Site and Subsequent Contraction Sequence and Functional Effects With Bedside Radionuclide Angiography

JACC Cardiovascular Imaging ◽

10.1016/j.jcmg.2008.05.013 ◽

2008 ◽

Vol 1 (5) ◽

pp. 605-613 ◽

Cited By ~ 6

Author(s):

Elias Botvinick ◽

Jesse Davis ◽

Michael Dae ◽

John O'Connell ◽

Norberto Schechtmann ◽

...

Keyword(s):

Ventricular Tachycardia ◽

Radionuclide Angiography ◽

Exit Site

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Exit-Site Location Does Not Influence Peritoneal Catheter Infection Rate

Peritoneal Dialysis International ◽

10.1177/089686088900900210 ◽

1989 ◽

Vol 9 (2) ◽

pp. 127-129 ◽

Cited By ~ 10

Author(s):

Beth Piraino ◽

Judith Bernardini ◽

James R. Johnston ◽

Michael I. Sorkin

Keyword(s):

Risk Factors ◽

Infection Rate ◽

Important Determinant ◽

Patient Comfort ◽

Infection Rates ◽

Site Location ◽

Exit Site ◽

Peritoneal Catheter ◽

Catheter Infection ◽

Catheter Infections

Peritoneal catheter infections are a cause of peritonitis, catheter loss, and permanent transfer of continuous ambulatory peritoneal dialysis (CAPO) patients to hemodialysis. Risk factors for catheter infections have not been delineated. We investigated the location of the peritoneal exit-site location as a risk factor for catheter infection and loss. There was no relationship between catheter infection rates and exit location. Catheters exiting on the beltline had a median infection rate of 0.5 episodesl year, as opposed to 1.2 episodes/year for catheters exiting above the beltline and 0.9 episodes/ year for catheters exiting below the beltline (ns). The percentage of catheters that became infected and required removal was the same for catheters exiting above, below, or on the beltline. Although we recommend avoiding the beltline for patient comfort, exit-site location is not an important determinant of infection rates or catheter outcome.

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