Efficacy and Myocardial Injury With Subcutaneous Implantable Cardioverter Defibrillators　– Computer Simulation of Defibrillation Shock Conduction –

Noro, Mahito; Zhu, Xin; Enomoto, Yoshinari; Asami, Masatoshi; Ishii, Rina; Toyoda, Yasutake; Sahara, Naohiko; Takagi, Takahito; Narabayasi, Yuriko; Hashimoto, H; Ito, Naoshi; Kujime, Shingo; Oikawa, Yasuhiro; Tatsunami, Hiroyuki; Sakai, Tsuyoshi; Nakamura, K; Saruta, Takao; Sugi, Kaoru

doi:10.1253/circj.cj-15-0883

Cited by 8 publications

(5 citation statements)

References 20 publications

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“…An in silico study reported a lower defibrillation threshold for right-sided than for left-sided S-ICD lead placement. 29 An observational study in a general S-ICD population 30 demonstrated similar rates of successful defibrillation with the first 65J shock (79% left-sided and 73% right-sided lead; P=NS), and similar rates of ineffective shocks (2.9% left-sided and 1.9% right-sided lead; P=NS). A randomized controlled trial is needed before right-sided S-ICD lead placement can be recommended as preferential in ACHD.…”

Section: Nearly Half Of the Contemporary Achd Population Is Ineligiblmentioning

confidence: 93%

Eligibility for Subcutaneous Implantable Cardioverter Defibrillator in Congenital Heart Disease

Wang

Javadekar

Rajagopalan

et al. 2019

Preprint

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Background: The goals of this study were: assess left-and right-sided subcutaneous implantable cardioverter-defibrillator (SICD) eligibility in adult congenital heart disease (ACHD) patients, use machine learning to predict SICD eligibility in ACHD patients, and transform 12-lead ECG to S-ICD 3-lead ECG, and vice versa. Methods: ACHD outpatients (n=101; age 42±14 y; 52% female; 85% white; left ventricular ejection fraction (LVEF) 56±9%) were enrolled in a prospective study. Supine and standing 12-lead ECG was recorded simultaneously with a right- and left-sided S-ICD 3-lead ECG. Peak-to-peak QRS and T amplitudes, RR, PR, QT, QTc, QRS intervals, Tmax, and R/Tmax (31 predictor variables) were tested. Model selection, training, and testing were performed using supine ECG datasets. Validation was performed using standing ECG datasets and out-of-sample non-ACHD population (n=68; age 54±16 y; 54% female; 94% white; LVEF 61±8%). Results: A 40% of participants were ineligible for S-ICD. Tetralogy of Fallot patients passed right-sided screening (57%) more often than left-sided (21%; McNemar's χ2 P=0.025). The ridge model demonstrated the best cross-validation function. Validation of the ridge models was satisfactory for standing left-sided [ROC AUC 0.687 (95%CI 0.582-0.791)] and right-sided [ROC AUC 0.655(95%CI 0.549-0.762)] SICD eligibility prediction. Out-of-sample validation in the non-ACHD population yielded a 100% sensitivity of the pre-selected threshold for the elastic net model. Validation of the transformation matrices showed satisfactory agreement (<0.1 mV difference). Conclusion: Nearly half of the contemporary ACHD population is ineligible for S-ICD. Machine-learning prediction of SICD eligibility can be used for screening of SICD candidates. Clinical Trial Registration: URL: www.clinicaltrials.gov Unique identifier: NCT03209726

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Section: Nearly Half Of the Contemporary Achd Population Is Ineligiblmentioning

confidence: 93%

Eligibility for Subcutaneous Implantable Cardioverter Defibrillator in Congenital Heart Disease

Wang

Javadekar

Rajagopalan

et al. 2019

Preprint

View full text Add to dashboard Cite

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“…31 A study on defibrillation efficacy of S-ICD using a computer simulation model reported that DFT for the coil lead paced at the right parasternal margin may be lower than that for the coil lead placed at the left parasternal margin. 37 Additionally, a screening ECG test result cannot guarantee the absence of inappropriate shock due to T-wave oversensing after S-ICD implantation. We tested screening ECG in the supine and standing positions only at rest; screening ECG during exercise may be helpful to detect T-wave oversensing.…”

Section: Study Limitationsmentioning

confidence: 99%

Right Parasternal Lead Placement Increases Eligibility for Subcutaneous Implantable Cardioverter Defibrillator Therapy in Adults With Congenital Heart Disease

Okamura

McLeod

DeSimone

et al. 2016

Circ J

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Background:The subcutaneous implantable cardioverter defibrillator (S-ICD) provides an attractive option for patients with congenital heart disease (CHD) in whom a transvenous defibrillator is contraindicated. Given the unusual cardiac anatomy and repolarization strain, the surface electrocardiogram (ECG) is frequently abnormal, potentially increasing the screen failure rate. Methods and Results:We prospectively screened 100 adult CHD patients regardless of the presence of clinical indication for ICD utilizing a standard left sternal lead placement, as well as a right parasternal position. Baseline patient and 12-lead ECG characteristics were examined to assess for predictors of screen failure. Average patient age was 48±14 years, average QRS duration was 134±37 ms, and 13 patients were pacemaker dependent. Using the standard left parasternal electrode position, 21 patients failed screening. Of these 21 patients with screen failure, 9 passed screening with the use of right parasternal electrode positioning, reducing screening failure rate from 21% to 12%. QT interval and inverted T wave anywhere in V2-V6 leads were found to be independent predictors of left parasternal screening failure (P=0.01 and P=0.04, respectively). Conclusions:Utilization of both left and right parasternal screening should be used in evaluation of CHD patients for S-ICD eligibility. ECG repolarization characteristics were also identified as novel predictors of screening failure in this group. (Circ J 2016; 80: 1328 -1335

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“…The DFT used in most of the previous simulation studies using static electrostatic field analysis was defined as the minimum energy output of the ICD generator, which generates a potential gradient > 5 V/cm in > 90% of the myocardium based on the critical mass hypothesis. 7,8,25 Because the potential distribution of conventional rod-like electrodes shows an exponential distribution, it is inevitable that the potential gradient between the electrodes becomes non-uniform, as shown in…”

Section: Mechanisms Of the Low-energy Defibrillationmentioning

confidence: 99%

“…This simulator integrates the molecular and cellular mechanisms of cardiac excitation and contraction to reproduce the cardiac electrophysiology and hemodynamics at the organ level based on a finite element method with parallel computation. 6 Although there have been many simulation studies on defibrillation, most of them are based on static electrostatic field analysis, 7,8 a small region model, 9,10 or a small animal model. 11,12 Furthermore, there are few studies that have actually calculated the defibrillation threshold (DFT) of the human ventricle.…”

Section: Introductionmentioning

confidence: 99%

Low‐energy defibrillation using a base–apex epicardial electrode

Okada,

Washio,

Sugiura

et al. 2023

Pacing Clinical Electrophis

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BackgroundCurrent implantable cardioverter defibrillators (ICDs) require electric conduction with high voltage and high energy, which can impair cardiac function and induce another malignant arrhythmia. As a result, there has been a demand for an ICD that can effectively operate with lower energy to mitigate the risks of a strong electric shock.MethodsA pair of sheet‐shaped electrodes covering the heart were analyzed in three configurations (top–bottom, left–right, and front–back) using a heart simulator. We also varied the distance between the two electrodes (clearance) to identify the electrode shape with the lowest defibrillation threshold (DFT). We also investigated the ICD shock waveform, shock direction, and the effect of the backside insulator of the electrode.ResultsThe DFT was high when the clearance was too small and the DFT was high even when the clearance was too large, suggesting that an optimal value clearance. The top–bottom electrodes with optimal clearance showed the lowest DFT when the biphasic shocks set the top electrode to a high potential first and then the bottom electrode was set to a high potential. An interval between a first shock waveform and a second shock waveform should be provided for low‐energy defibrillation. Because the insulator prevents unnecessary current flow to the backside, the DFT of the electrodes with insulators is less than those without insulators.ConclusionPainless defibrillation using sheet‐shaped electrodes on the epicardium is predicated on the basis of results using a heart simulator.

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Efficacy and Myocardial Injury With Subcutaneous Implantable Cardioverter Defibrillators　– Computer Simulation of Defibrillation Shock Conduction –

Cited by 8 publications

References 20 publications

Eligibility for Subcutaneous Implantable Cardioverter Defibrillator in Congenital Heart Disease

Eligibility for Subcutaneous Implantable Cardioverter Defibrillator in Congenital Heart Disease

Right Parasternal Lead Placement Increases Eligibility for Subcutaneous Implantable Cardioverter Defibrillator Therapy in Adults With Congenital Heart Disease

Low‐energy defibrillation using a base–apex epicardial electrode

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Efficacy and Myocardial Injury With Subcutaneous Implantable Cardioverter Defibrillators – Computer Simulation of Defibrillation Shock Conduction –

Cited by 8 publications

References 20 publications

Eligibility for Subcutaneous Implantable Cardioverter Defibrillator in Congenital Heart Disease

Eligibility for Subcutaneous Implantable Cardioverter Defibrillator in Congenital Heart Disease

Right Parasternal Lead Placement Increases Eligibility for Subcutaneous Implantable Cardioverter Defibrillator Therapy in Adults With Congenital Heart Disease

Low‐energy defibrillation using a base–apex epicardial electrode

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Efficacy and Myocardial Injury With Subcutaneous Implantable Cardioverter Defibrillators　– Computer Simulation of Defibrillation Shock Conduction –