Karoly Kaszala | Virginia Commonwealth University (original) (raw)

Papers by Karoly Kaszala

Research paper thumbnail of Resolution of Bundle Branch Block During Cryoablation: Continue Ablating or Not?

Journal of Cardiovascular Electrophysiology, 2014

ABSTRACT A 65-year-old man with recurrent palpitations and documented supraventricular tachycardi... more ABSTRACT A 65-year-old man with recurrent palpitations and documented supraventricular tachycardia was referred for electrophysiology study and catheter ablation. His baseline ECG is shown in Figure 1 suggesting a parahisian accessory pathway. This article is protected by copyright. All rights reserved.

Research paper thumbnail of Hemodynamic Optimization Following Biventricular Device Implant: Do We Still Need an Echocardiogram?

JACC. Cardiovascular imaging, Jan 11, 2018

Research paper thumbnail of Fluoroscopy Reduction During Device Implantation by Using Three‐Dimensional Navigation. A single‐center experience

Journal of Cardiovascular Electrophysiology

Research paper thumbnail of Epicardial injection of nanoformulated calcium into cardiac ganglionic plexi suppresses autonomic nerve activity and postoperative atrial fibrillation

Research paper thumbnail of Fix What is Broken: Scar Homogenization in Persistent Atrial Fibrillation

Journal of Cardiovascular Electrophysiology

Research paper thumbnail of How do you want your pocket? Well done or medium rare?

Journal of Cardiovascular Electrophysiology

Research paper thumbnail of Scar Homogenization in Atrial Fibrillation Ablation: Evolution and Practice

Journal of atrial fibrillation

Atrial fibrillation (AF) ablation has emerged as the preferred rhythm control strategy for sympto... more Atrial fibrillation (AF) ablation has emerged as the preferred rhythm control strategy for symptomatic paroxysmal AF refractory or intolerant to at least one class I or III antiarrhythmic medication. Since the initial observation by Haissaguerre and colleagues, of pulmonary vein triggers initiating atrial fibrillation (AF), pulmonary vein isolation (PVI) has become the cornerstone for paroxysmal AF ablation therapy.

Research paper thumbnail of Evaluation, Troubleshooting, and Management of Pacing System Malfunctions

Cardiac Pacing and ICDs, 2014

Research paper thumbnail of Electromagnetic Interference and CIEDs

Clinical Cardiac Pacing, Defibrillation and Resynchronization Therapy, 2011

Research paper thumbnail of Abstract 13430: ‘Dyads’ Function as Ion Channel Hubs in Cardiac Myocytes and Junctophilin-2 Plays a Critical Role in Stabilizing Channel Expression in Dyads

Circulation, Nov 25, 2014

Research paper thumbnail of Abstract 15020: A Placebo-Controlled, Double-Blind, Randomized, Multicenter Study to Assess the Effects of Dronedarone on Atrial Fibrillation Burden in Subjects with Permanent Pacemakers (HESTIA)

Circulation, Nov 20, 2012

Research paper thumbnail of Septic pulmonary embolism in a patient with defibrillator lead endocarditis

American Journal of Respiratory and Critical Care Medicine, Jan 15, 2012

... Pacing Clin Electrophysiol 2007;30:12–19. Medline. 2.↵: Sohail MR,; Uslan DZ,; Khan AH,; Frie... more ... Pacing Clin Electrophysiol 2007;30:12–19. Medline. 2.↵: Sohail MR,; Uslan DZ,; Khan AH,; Friedman PA,; Hayes DL,; Wilson WR,; Steckelberg JM,; Stoner SM,; Baddour LM. . Risk factor analysis of permanent pacemaker infection. Clin Infect Dis 2007;45:166–173. ...

Research paper thumbnail of Abstract 15776: Determination of Maximum Isotherm to Achieve Conduction Block During Cryoablation

Circulation, Nov 25, 2014

Research paper thumbnail of Impact of Ventricular Ectopic Burden in a Premature Ventricular Contraction-induced Cardiomyopathy Animal Model

Heart Rhythm, 2015

Frequent premature ventricular contractions (PVC) have been associated with PVC-induced cardiomyo... more Frequent premature ventricular contractions (PVC) have been associated with PVC-induced cardiomyopathy (CM) in some patients. Understand the cardiac consequences of different PVC burden and minimum burden required to induce LV dysfunction. RV apical PVCs at a coupling interval of 240ms were introduced at different PVC burden in 9 mongrel canines. A stepwise increase in PVC burden was implemented every 8 weeks from 0% (baseline), 7%, 14%, 25%, 33% to 50% using our premature pacing algorithm. Echocardiogram and 24-hr Holter were obtained at 4- and 8-week period at each PVC burden with a single blinded reader assessing all echocardiographic parameters including speckle tracking imaging (GE EchoPAC). CM was defined as LVEF < 50% or a decrease >10% points. IL-6 and pro-BNP levels were obtained at the end of each PVC burden. LVEF±SD (mean heart rate ± SD) for 0%, 7%, 14%, 33%, and 50% at 8 weeks for each PVC burden were 57±2.9% (85±13bpm); 54.4±3% (81±10bpm); 53.3±5% (77±12bpm); 51.1±4.2% (79±14bpm); 47.7±3.8% (80±14bpm); 44.7±1.9% (157±43bpm). PVC-induced CM was present in 11.1%, 44.4%, and 100% of animals with 25%, 33% and 50% PVC burden, respectively. E/A ratio and radial strain decreased while LA size increased beyond 33% PVC burden. No changes in pro-BNP and IL-6 levels were noted at any PVC burden. LV systolic function (LVEF, and radial strain) declined linearly as PVC burden increased. PVC-induced CM developed in some canines with 25% and 33% PVC burden, but developed in all animals with 50% PVC burden.

Research paper thumbnail of Sustained Multiple Railroad Tracks on Implantable Cardiac Defibrillator Interval Plots: Mechanisms and Management

Circulation. Arrhythmia and electrophysiology, 2015

Research paper thumbnail of Application of Excimer Laser for Percutaneous Extraction of Pacemaker and Defibrillator Leads: Experience from the Hunter Holmes McGuire Veterans Administration Medical Center and the Virginia Commonwealth University

Lasers in Cardiovascular Interventions, 2015

Research paper thumbnail of Abnormal Left Ventricular Mechanics of Ventricular Ectopic Beats: Insights into Origin and Coupling Interval in Premature Ventricular Contraction-Induced Cardiomyopathy

Circulation. Arrhythmia and electrophysiology, Jan 21, 2015

-Left ventricular (LV) dyssynchrony caused by premature ventricular contractions (PVCs) has been ... more -Left ventricular (LV) dyssynchrony caused by premature ventricular contractions (PVCs) has been proposed as a mechanism of PVC-induced cardiomyopathy (CM). We sought to understand the impact of different PVC locations and coupling intervals (prematurity) on LV regional mechanics and global function of the PVC beat itself. -Using our premature pacing algorithm, pentageminal PVCs at coupling intervals of 200-375ms were delivered from the epicardial right ventricular (RV) apex, RV outflow tract (RVOT), and LV free wall, as well as premature atrial contractions (PACs) from the left atrial (LA) appendage at a coupling interval of 200ms in seven healthy canines. LV short axis echocardiographic images, LV stroke volume (SV) and dP/dtmax were obtained during all ectopic beats and VP. LV dyssynchrony was assessed by dispersion of QRS-to-peak strain (earliest - last QRS-to-peak strain) between 6 different LV segments during each of the aforementioned beats (GE, EchoPac). LV dyssynchrony was greater during long- rather than short-coupled PVCs and PVCs at 375ms compared with rapid VP at 400ms (P<0.0001), whereas, no difference was found between PVC locations. Longer PVC coupling intervals were associated with greater SV and dP/dtmax despite more pronounced dyssynchrony (P<0.001). -PVCs with longer coupling intervals demonstrate more pronounced LV dyssynchrony, whereas PVC location has minimal impact. LV dyssynchrony cannot be attributed to prematurity or abnormal ventricular activation alone, but rather to a combination of both. This study suggests that late-coupled PVCs may cause a more severe cardiomyopathy if dyssynchrony is the leading mechanism responsible for PVC-induced CM.

Research paper thumbnail of Implantable cardioverter defibrillators: function and troubleshooting

Indian heart journal

As a result of large, multicenter trials supporting ICDs for prevention of sudden cardiac arrest,... more As a result of large, multicenter trials supporting ICDs for prevention of sudden cardiac arrest, there has been an exponential increase in ICD device therapy. Cardiologists and general practitioners are increasingly faced with the challenge to evaluate and troubleshoot device problems. In this review, we provide an overview of basic ICD function and malfunction and show examples of common ICD problems and troubleshooting.

Research paper thumbnail of Disparity in left ventricular stimulation among different pacing configurations in cardiac resynchronization therapy

Circulation. Arrhythmia and electrophysiology, 2012

Cardiac resynchronization therapy (CRT) demands high energy utilization due to continuous biventr... more Cardiac resynchronization therapy (CRT) demands high energy utilization due to continuous biventricular pacing. Current technology allows 6 pacing configurations for a bipolar left ventricular (LV) lead. Understanding the energy requirements for each configuration will allow optimization of pacing output. Pacing impedance, LV voltage threshold at 1.5 ms (rheobase) and 0.4 ms and chronaxie were obtained in 6 LV configurations in 49 consecutive patients undergoing CRT implantation or replacement. Strength-duration curves were derived using the Lapicque formula. Pacing impedances and voltage thresholds at 1.5 and 0.4 ms, calculated minimum threshold energy at chronaxie, current drain, energy thresholds at 0.4 ms, and strength-duration curves were statistically different between LV configurations (P<0.05). The lowest threshold energy requirements were found in Tip→right ventricular (RV) coil and Tip→Can configuration. Energy strength-duration curves involving the ring as the cathode ...

Research paper thumbnail of Biophysics of the Second-Generation Cryoballoon: Cryobiology of the Big Freeze

Circulation: Arrhythmia and Electrophysiology, 2015

Dr. Karoly Kaszala has received research grant from Medtronic. Dr Kenneth Ellenbogen has received... more Dr. Karoly Kaszala has received research grant from Medtronic. Dr Kenneth Ellenbogen has received honorarium, consulting and research grants from Medtronic. 17. Mazur P. Physical and temporal factors involved in the death of yeast at subzero temperatures. Biophys J. 1961;1:247-264.

Research paper thumbnail of Resolution of Bundle Branch Block During Cryoablation: Continue Ablating or Not?

Journal of Cardiovascular Electrophysiology, 2014

ABSTRACT A 65-year-old man with recurrent palpitations and documented supraventricular tachycardi... more ABSTRACT A 65-year-old man with recurrent palpitations and documented supraventricular tachycardia was referred for electrophysiology study and catheter ablation. His baseline ECG is shown in Figure 1 suggesting a parahisian accessory pathway. This article is protected by copyright. All rights reserved.

Research paper thumbnail of Hemodynamic Optimization Following Biventricular Device Implant: Do We Still Need an Echocardiogram?

JACC. Cardiovascular imaging, Jan 11, 2018

Research paper thumbnail of Fluoroscopy Reduction During Device Implantation by Using Three‐Dimensional Navigation. A single‐center experience

Journal of Cardiovascular Electrophysiology

Research paper thumbnail of Epicardial injection of nanoformulated calcium into cardiac ganglionic plexi suppresses autonomic nerve activity and postoperative atrial fibrillation

Research paper thumbnail of Fix What is Broken: Scar Homogenization in Persistent Atrial Fibrillation

Journal of Cardiovascular Electrophysiology

Research paper thumbnail of How do you want your pocket? Well done or medium rare?

Journal of Cardiovascular Electrophysiology

Research paper thumbnail of Scar Homogenization in Atrial Fibrillation Ablation: Evolution and Practice

Journal of atrial fibrillation

Atrial fibrillation (AF) ablation has emerged as the preferred rhythm control strategy for sympto... more Atrial fibrillation (AF) ablation has emerged as the preferred rhythm control strategy for symptomatic paroxysmal AF refractory or intolerant to at least one class I or III antiarrhythmic medication. Since the initial observation by Haissaguerre and colleagues, of pulmonary vein triggers initiating atrial fibrillation (AF), pulmonary vein isolation (PVI) has become the cornerstone for paroxysmal AF ablation therapy.

Research paper thumbnail of Evaluation, Troubleshooting, and Management of Pacing System Malfunctions

Cardiac Pacing and ICDs, 2014

Research paper thumbnail of Electromagnetic Interference and CIEDs

Clinical Cardiac Pacing, Defibrillation and Resynchronization Therapy, 2011

Research paper thumbnail of Abstract 13430: ‘Dyads’ Function as Ion Channel Hubs in Cardiac Myocytes and Junctophilin-2 Plays a Critical Role in Stabilizing Channel Expression in Dyads

Circulation, Nov 25, 2014

Research paper thumbnail of Abstract 15020: A Placebo-Controlled, Double-Blind, Randomized, Multicenter Study to Assess the Effects of Dronedarone on Atrial Fibrillation Burden in Subjects with Permanent Pacemakers (HESTIA)

Circulation, Nov 20, 2012

Research paper thumbnail of Septic pulmonary embolism in a patient with defibrillator lead endocarditis

American Journal of Respiratory and Critical Care Medicine, Jan 15, 2012

... Pacing Clin Electrophysiol 2007;30:12–19. Medline. 2.↵: Sohail MR,; Uslan DZ,; Khan AH,; Frie... more ... Pacing Clin Electrophysiol 2007;30:12–19. Medline. 2.↵: Sohail MR,; Uslan DZ,; Khan AH,; Friedman PA,; Hayes DL,; Wilson WR,; Steckelberg JM,; Stoner SM,; Baddour LM. . Risk factor analysis of permanent pacemaker infection. Clin Infect Dis 2007;45:166–173. ...

Research paper thumbnail of Abstract 15776: Determination of Maximum Isotherm to Achieve Conduction Block During Cryoablation

Circulation, Nov 25, 2014

Research paper thumbnail of Impact of Ventricular Ectopic Burden in a Premature Ventricular Contraction-induced Cardiomyopathy Animal Model

Heart Rhythm, 2015

Frequent premature ventricular contractions (PVC) have been associated with PVC-induced cardiomyo... more Frequent premature ventricular contractions (PVC) have been associated with PVC-induced cardiomyopathy (CM) in some patients. Understand the cardiac consequences of different PVC burden and minimum burden required to induce LV dysfunction. RV apical PVCs at a coupling interval of 240ms were introduced at different PVC burden in 9 mongrel canines. A stepwise increase in PVC burden was implemented every 8 weeks from 0% (baseline), 7%, 14%, 25%, 33% to 50% using our premature pacing algorithm. Echocardiogram and 24-hr Holter were obtained at 4- and 8-week period at each PVC burden with a single blinded reader assessing all echocardiographic parameters including speckle tracking imaging (GE EchoPAC). CM was defined as LVEF &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; 50% or a decrease &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;gt;10% points. IL-6 and pro-BNP levels were obtained at the end of each PVC burden. LVEF±SD (mean heart rate ± SD) for 0%, 7%, 14%, 33%, and 50% at 8 weeks for each PVC burden were 57±2.9% (85±13bpm); 54.4±3% (81±10bpm); 53.3±5% (77±12bpm); 51.1±4.2% (79±14bpm); 47.7±3.8% (80±14bpm); 44.7±1.9% (157±43bpm). PVC-induced CM was present in 11.1%, 44.4%, and 100% of animals with 25%, 33% and 50% PVC burden, respectively. E/A ratio and radial strain decreased while LA size increased beyond 33% PVC burden. No changes in pro-BNP and IL-6 levels were noted at any PVC burden. LV systolic function (LVEF, and radial strain) declined linearly as PVC burden increased. PVC-induced CM developed in some canines with 25% and 33% PVC burden, but developed in all animals with 50% PVC burden.

Research paper thumbnail of Sustained Multiple Railroad Tracks on Implantable Cardiac Defibrillator Interval Plots: Mechanisms and Management

Circulation. Arrhythmia and electrophysiology, 2015

Research paper thumbnail of Application of Excimer Laser for Percutaneous Extraction of Pacemaker and Defibrillator Leads: Experience from the Hunter Holmes McGuire Veterans Administration Medical Center and the Virginia Commonwealth University

Lasers in Cardiovascular Interventions, 2015

Research paper thumbnail of Abnormal Left Ventricular Mechanics of Ventricular Ectopic Beats: Insights into Origin and Coupling Interval in Premature Ventricular Contraction-Induced Cardiomyopathy

Circulation. Arrhythmia and electrophysiology, Jan 21, 2015

-Left ventricular (LV) dyssynchrony caused by premature ventricular contractions (PVCs) has been ... more -Left ventricular (LV) dyssynchrony caused by premature ventricular contractions (PVCs) has been proposed as a mechanism of PVC-induced cardiomyopathy (CM). We sought to understand the impact of different PVC locations and coupling intervals (prematurity) on LV regional mechanics and global function of the PVC beat itself. -Using our premature pacing algorithm, pentageminal PVCs at coupling intervals of 200-375ms were delivered from the epicardial right ventricular (RV) apex, RV outflow tract (RVOT), and LV free wall, as well as premature atrial contractions (PACs) from the left atrial (LA) appendage at a coupling interval of 200ms in seven healthy canines. LV short axis echocardiographic images, LV stroke volume (SV) and dP/dtmax were obtained during all ectopic beats and VP. LV dyssynchrony was assessed by dispersion of QRS-to-peak strain (earliest - last QRS-to-peak strain) between 6 different LV segments during each of the aforementioned beats (GE, EchoPac). LV dyssynchrony was greater during long- rather than short-coupled PVCs and PVCs at 375ms compared with rapid VP at 400ms (P&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt;0.0001), whereas, no difference was found between PVC locations. Longer PVC coupling intervals were associated with greater SV and dP/dtmax despite more pronounced dyssynchrony (P&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt;0.001). -PVCs with longer coupling intervals demonstrate more pronounced LV dyssynchrony, whereas PVC location has minimal impact. LV dyssynchrony cannot be attributed to prematurity or abnormal ventricular activation alone, but rather to a combination of both. This study suggests that late-coupled PVCs may cause a more severe cardiomyopathy if dyssynchrony is the leading mechanism responsible for PVC-induced CM.

Research paper thumbnail of Implantable cardioverter defibrillators: function and troubleshooting

Indian heart journal

As a result of large, multicenter trials supporting ICDs for prevention of sudden cardiac arrest,... more As a result of large, multicenter trials supporting ICDs for prevention of sudden cardiac arrest, there has been an exponential increase in ICD device therapy. Cardiologists and general practitioners are increasingly faced with the challenge to evaluate and troubleshoot device problems. In this review, we provide an overview of basic ICD function and malfunction and show examples of common ICD problems and troubleshooting.

Research paper thumbnail of Disparity in left ventricular stimulation among different pacing configurations in cardiac resynchronization therapy

Circulation. Arrhythmia and electrophysiology, 2012

Cardiac resynchronization therapy (CRT) demands high energy utilization due to continuous biventr... more Cardiac resynchronization therapy (CRT) demands high energy utilization due to continuous biventricular pacing. Current technology allows 6 pacing configurations for a bipolar left ventricular (LV) lead. Understanding the energy requirements for each configuration will allow optimization of pacing output. Pacing impedance, LV voltage threshold at 1.5 ms (rheobase) and 0.4 ms and chronaxie were obtained in 6 LV configurations in 49 consecutive patients undergoing CRT implantation or replacement. Strength-duration curves were derived using the Lapicque formula. Pacing impedances and voltage thresholds at 1.5 and 0.4 ms, calculated minimum threshold energy at chronaxie, current drain, energy thresholds at 0.4 ms, and strength-duration curves were statistically different between LV configurations (P<0.05). The lowest threshold energy requirements were found in Tip→right ventricular (RV) coil and Tip→Can configuration. Energy strength-duration curves involving the ring as the cathode ...

Research paper thumbnail of Biophysics of the Second-Generation Cryoballoon: Cryobiology of the Big Freeze

Circulation: Arrhythmia and Electrophysiology, 2015

Dr. Karoly Kaszala has received research grant from Medtronic. Dr Kenneth Ellenbogen has received... more Dr. Karoly Kaszala has received research grant from Medtronic. Dr Kenneth Ellenbogen has received honorarium, consulting and research grants from Medtronic. 17. Mazur P. Physical and temporal factors involved in the death of yeast at subzero temperatures. Biophys J. 1961;1:247-264.