Daniel Lustgarten - Academia.edu (original) (raw)

Papers by Daniel Lustgarten

Heart Rhythm, May 1, 2016

Additional Supporting Information may be found in the online version of this article. Copies: Thi... more Additional Supporting Information may be found in the online version of this article. Copies: This document is available on the World Wide Web sites of the American College of Cardiology (www.acc.org), the Society for Cardiovascular Angiography and Interventions (scai.org), and the Heart Rhythm Society (hrsonline.org). This article is copublished in Catheterization and Cardiovascular Interventions and the Journal of the American College of Cardiology. This document was approved by the American College of Cardiology Board of Trustees and Executive Committee, the Society for Cardiovascular Angiography and Interventions Board of Trustees, and the Heart Rhythm Society Board of Trustees in December 2015.

Critical Care Medicine, Dec 1, 2004

Current Treatment Options in Cardiovascular Medicine, Nov 1, 2004

Heart Rhythm, Mar 1, 2022

The Journal of innovations in cardiac rhythm management, Apr 19, 2016

There has been a recent upsurge of interest in permanent His bundle pacing, given increased under... more There has been a recent upsurge of interest in permanent His bundle pacing, given increased understanding and appreciation of the role dyssynchronous ventricular activation plays in congestive heart failure and atrial fibrillation. Permanent His bundle pacing gives implanters the ability to avoid causing ventricular dyssynchrony in patients dependent on ventricular pacing, and can provide an alternative means to implementing cardiac resynchronization therapy in patients with bundle branch disease and congestive heart failure. This paper describes a step-wise approach to implanting permanent His bundle pacing leads, with a clear demonstration of techniques and observations encountered during the course of typical His bundle lead implantations, including consideration of potential pitfalls and workarounds.

Journal of the American Heart Association, Sep 1, 2020

Background Increases in heart rate are thought to result in incomplete left ventricular (LV) rela... more Background Increases in heart rate are thought to result in incomplete left ventricular (LV) relaxation and elevated filling pressures in patients with heart failure with preserved ejection fraction (HFpEF). Experimental studies in isolated human myocardium have suggested that incomplete relaxation is a result of cellular Ca 2+ overload caused by increased myocardial Na + levels. We tested these heart rate paradigms in patients with HFpEF and referent controls without hypertension. Methods and Results In 22 fully sedated and instrumented patients (12 controls and 10 patients with HFpEF) in sinus rhythm with a preserved ejection fraction (≥50%) we assessed left‐sided filling pressures and volumes in sinus rhythm and with atrial pacing (95 beats per minute and 125 beats per minute) before atrial fibrillation ablation. Coronary sinus blood samples and flow measurements were also obtained. Seven women and 15 men were studied (aged 59±10 years, ejection fraction 61%±4%). Patients with HFpEF had a history of hypertension, dyspnea on exertion, concentric LV remodeling and a dilated left atrium, whereas controls did not. Pacing at 125 beats per minute lowered the mean LV end‐diastolic pressure in both groups (controls −4.3±4.1 mm Hg versus patients with HFpEF −8.5±6.0 mm Hg, P =0.08). Pacing also reduced LV end‐diastolic volumes. The volume loss was about twice as much in the HFpEF group (controls −15%±14% versus patients with HFpEF −32%±11%, P =0.009). Coronary venous [Ca 2+ ] increased after pacing at 125 beats per minute in patients with HFpEF but not in controls. [Na + ] did not change. Conclusions Higher resting heart rates are associated with lower filling pressures in patients with and without HFpEF. Incomplete relaxation and LV filling at high heart rates lead to a reduction in LV volumes that is more pronounced in patients with HFpEF and may be associated with myocardial Ca 2+ retention.

Heart Rhythm, May 1, 2006

Coronary Artery Disease, Feb 1, 2003

Introduction The placement and manipulation of standard intravascular electrode catheters has all... more Introduction The placement and manipulation of standard intravascular electrode catheters has allowed remarkable success for mapping and ablation of a variety of arrhythmias [1]. These arrhythmias, such as AV nodal reentrant tachycardia, reentry using an accessory pathway and typical atrial flutter, involve anatomic substrates that can be readily interpreted utilizing biplane fluoroscopic information coupled with basic electrophysiological data. Multielectrode mapping catheters in the right atrial appendage, bundle of His, right ventricular septum and coronary sinus make it readily possible to identify structures such as the slow pathway inputs into the AV node, the atrioventricular annuli and the cavotricuspid isthmus. The fact that arrhythmias involving these structures tend to be sustained, hemodynamically well tolerated and constrained by readily definable anatomic barriers, allows diagnosis and treatment to be achieved relatively efficiently on the basis of fluoroscopic and electrophysiological data alone.

Journal of Cardiac Failure, Aug 1, 2009

diastolic dysfunction, the corresponding BNP levels were lower following sildenafil therapy (193 ... more diastolic dysfunction, the corresponding BNP levels were lower following sildenafil therapy (193 6 253 to 141 6 192 pg/mL, p!0.001). Echocardiographic Parameter observed n Before sildenafil After sildenafil P value Left Atrial diameter (diastolic) 64 3.72 cm 3.83 cm !0.05 Left Atrial Area 57 18.0 cm sq 19.1cm sq !0.05 Left Ventricular Internal Diameter (diastolic) 72 3.89 cm 4.07 cm !0.05 Left Ventricular Monoplane Volume (diastolic) 71 69.1 ml 76.4 ml !0.05 Left Ventricular Ejection Fraction 76 58% 57% NS Right Ventricular Systolic Pressure 69 78 mm Hg 75 mm Hg NS Tricuspid Regurgitant Jet Velocity 66 421 cm/ second 415 cm/ second NS NS 5 Not Significant. Conclusion: In patients with PAH, sildenafil therapy provided no significant reduction in estimated pulmonary artery systolic pressure but noticeable improvement in left-sided chamber dimensions and corresponding lower BNP levels, implying an improvement in preload delivery rather than directly reducing pulmonary artery pressures.

Pacing and Clinical Electrophysiology, Feb 1, 2007

A 55-year-old man without structural heart disease underwent electrophysiology study (EPS) to eva... more A 55-year-old man without structural heart disease underwent electrophysiology study (EPS) to evaluate recurrent episodes of sustained palpitations that reliably terminated with adenosine. At EPS, there was no evidence of preexcitation, and programmed stimulation from the right ventricular (RV) revealed a concentric activation pattern and decremental conduction. Parahisian pacing revealed a concentric atrial activation sequence and a longer stim-A interval with the loss of His capture (AVN response).1 Programmed stimulation from the high right atrium (RA) revealed dual antegrade atrioventricular (AV) node physiology. Rapid atrial pacing induced sustained supraven-

Journal of Electrocardiology, Oct 1, 2001

Atrial fibrillation (AF) is the most common arrhythmia seen in clinical practice and results in t... more Atrial fibrillation (AF) is the most common arrhythmia seen in clinical practice and results in the largest number of arrhythmia related hospital admissions. Despite the enormity of its impact on patients and the health care system, current medical therapy for AF is inadequate. Therapeutic approaches have been guided by understanding of fibrillation mechanisms. AF results from multiple simultaneous reentrant wavefronts. This is a diffuse and dynamic substrate with no discrete anatomic target. The catheter mediated "Maze" procedure employs creation of linear lesions to divide the atria into segments too small to support reentrant activation. Using current catheter technology this is a challenging procedure with low success rates and high complication rates. The observation that rapid focal firing of atrial myocytes within the pulmonary veins initiates fibrillation in the majority of paroxysmal AF patients has led to an entirely new ablation strategy. The sites of firing that initiate AF are targeted for ablation. Thus the paradigm for AF ablation has changed dramatically from altering the substrate of ongoing fibrillation to elimination of the triggers that initiate fibrillation. Initial experience revealed that multiple sites in the pulmonary veins are capable of rapid firing. Unfortunately not all sites fire during an ablation procedure. Sites that are quiescent during an ablation procedure may result in AF recurrence despite acute success. Ablation strategy has thus changed yet again to electrical isolation of all pulmonary venous tissue from the left atrium. The evolution of ablation strategies has paralleled our understanding of AF mechanisms. Elucidation of the mechanisms responsible for venous firing may lead to more specific therapy for the prevention of AF in the future.

Cold Spring Harbor Symposia on Quantitative Biology, 1989

Pacing and Clinical Electrophysiology, Sep 1, 2011

Background: Ablation of atrial autonomic inputs exerts antifibrillatory effects. However, because... more Background: Ablation of atrial autonomic inputs exerts antifibrillatory effects. However, because ablation destroys both myocardium and nerve cells, the effect of autonomic withdrawal alone remains unclear. We therefore examined the effects of pharmacologic autonomic blockade (PAB) on frequency and fractionation in patients with atrial fibrillation (AF). Methods: Esmolol and atropine were administered and electrograms were recorded simultaneously from both atria and the coronary sinus. In 17 patients, AF was recorded for 5 minutes and dominant frequency (DF) and continuous activity (CA) were compared before and during PAB. Results: Examination of the pooled data (537 sites, 17 patients) revealed a statistically significant decrease in mean DF (5.61-5.43Hz, P < 0.001) during PAB. Site-by-site analysis showed that 67% of sites slowed (0.45 ± 0.59 Hz), whereas 32% accelerated (0.49 ± 0.59Hz). Fractionation was reduced: median CA decreased from 31% to 26% (P < 0.001). In patient-by-patient analysis, mean DF/median CA decreased in 13 of 17 patients and increased in four. The spatial heterogeneity of DF decreased in nine of 17 patients (spatial coefficient of variation of DF at "nondriver sites" decreased by a mean of 2%). Conclusion: PAB decreases DF and CA in the majority of sites. Given the complexity of interactions between atrial cells during AF, the effects of PAB on DF and fractionation are more heterogeneous than the effects of PAB on isolated cells.

Pacing and Clinical Electrophysiology, Jul 1, 2009

Background: It has been proposed that microbubble (MB) monitoring can be used to safely titrate r... more Background: It has been proposed that microbubble (MB) monitoring can be used to safely titrate radiofrequency (RF) power. However, MB formation has been found to be an insensitive indicator of tissue temperature during RF delivery. We hypothesized that MB formation corresponds to surface-not tissue-temperature, and therefore would be an insensitive predictor of steam pops. Methods: An in vitro bovine heart model was used to measure surface and tissue temperatures during RF delivery under conditions designed to cause steam pops. Sensitivity of type II MB (MBII) formation as a predictor of steam pops and for surface temperatures more than 80 • C was calculated. Results: Of 105 lesions delivered, 99 steam pops occurred. Twenty-one steam pops were preceded by MBII. MBII were seen in 26 lesions, five of which were not associated with steam pop. Surface temperature at onset of MBII was 87 ± 9 • C versus a tissue temperature of 78 ± 23 • C (P = 0.044). Surface temperature at the time of steam pops was 71 ± 17 • C versus a tissue temperature of 102 ± 17 • C (P < 0.0001). The sensitivity of MBII for steam pops was 21%, and 58% for detecting surface temperature in excess of 80 • C. Conclusions: MBII correlated better with surface temperature than with tissue temperature; steam pops, on the other hand, correlated better with tissue temperature. MBII was an insensitive marker of steam pops and surface temperature in excess of 80 • C. Therefore, MBII should not be used to titrate RF power.

Physiological Reports

Intracellular calcium (Ca 2+) ion levels control cardiomyocyte contraction and relaxation (Ringer... more Intracellular calcium (Ca 2+) ion levels control cardiomyocyte contraction and relaxation (Ringer, 1883). Triggered by the action potential and facilitated by its concentration gradient, Ca 2+ enters cardiomyocytes mainly through voltage-dependent L-type Ca 2+-channels to initiate excitation-contraction coupling (Ebashi & Endo, 1968). Cumulative Ca 2+-entry depends on a variety of factors and conditions. Chief among them is the frequency with

Circulation, 2017

Background: It is a common concern that higher heart rates (HR) reduce coronary flow due to a sho... more Background: It is a common concern that higher heart rates (HR) reduce coronary flow due to a shortened diastolic interval and increase left atrial and ventricular filling pressures. Translational ...

His bundle pacing has the advantage of restoring physiologic ventricular activation, rather than ... more His bundle pacing has the advantage of restoring physiologic ventricular activation, rather than mimicking it as is the case with biventricular pacing. Engaging intact His-Purkinje fibers distal to conduction disease reestablishes multisite simultaneous endo-to-epicardial activation, resulting in normal torsional contraction and optimal cardiac output.

Cardiac Arrhythmias 1999 - Vol.1, 2000

Page 248. Treatment of Tachyarrhythmias Using Cryothermal Energy DL LUSTGARTEN, D. KEANE AND J. R... more Page 248. Treatment of Tachyarrhythmias Using Cryothermal Energy DL LUSTGARTEN, D. KEANE AND J. RUSKIN Introduction There are several energy sources available for the ablation of abnormally con-ducting cardiac ...