Krit Jongnarangsin

Inducibility of Paroxysmal Atrial Fibrillation by Isoproterenol and its Relation to the Mode of Onset of Atrial Fibrillation

Background: Isoproterenol has been used to assess inducibility during catheter ablation for paroxysmal PAF. However, no studies have determined the sensitivity and specificity of isoproterenol for the induction of AF. It also is not clear whether isoproterenol is equally effective in inducing AF in the clinical subtypes of vagotonic, adrenergic, and random AF.

Effect of catheter ablation on progression of paroxysmal atrial fibrillation.

Ablation and Progression of Atrial Fibrillation. Objective: The objective was to determine the effect of radiofrequency catheter ablation (RFA) on progression of paroxysmal atrial fibrillation (AF).

Clinical Value of Noninducibility by High‐Dose Isoproterenol Versus Rapid Atrial Pacing After Catheter Ablation of Paroxysmal Atrial Fibrillation

Noninducibility by High‐Dose Isoproterenol.u2002Objective: To determine the relative clinical value of noninducibility of atrial fibrillation (AF) by isoproterenol (ISO) and by rapid atrial pacing (RAP) in patients with paroxysmal AF (PAF).

Utility of atrial and ventricular cycle length variability in determining the mechanism of paroxysmal supraventricular tachycardia.

Introduction: No prior studies have systematically investigated the diagnostic value of cycle length (CL) variability in differentiating the mechanism of paroxysmal supraventricular tachycardia (PSVT).

Complex electrograms within the coronary sinus: time- and frequency-domain characteristics, effects of antral pulmonary vein isolation, and relationship to clinical outcome in patients with paroxysmal and persistent atrial fibrillation.

Background: The mechanistic and clinical significance of complex fractionated atrial electrograms (CFAE) in the coronary sinus (CS) has been unclear.

Prevalence of fever in patients undergoing left atrial ablation of atrial fibrillation guided by barium esophagraphy.

Background: Real‐time esophageal imaging is critical in avoiding esophageal injury. However, the safety of esophageal imaging with barium has not been specifically explored.

Time- and Frequency-Domain Characteristics of Atrial Electrograms During Sinus Rhythm and Atrial Fibrillation

Ablation and Spectral Characteristics of Fibrillation. Background: Complex fractionated atrial electrograms (CFAE) have been considered to be helpful during catheter ablation of atrial fibrillation (AF). The purpose of this study was to analyze the characteristics of CFAEs recorded during sinus rhythm (SR) and AF, and to determine their relationship to perpetuation of AF and clinical outcome.

Electromagnetic Interference in an Implantable Loop Recorder Caused by a Portable Digital Media Player

The implantable loop recorder has been shown to be a cost‐effective tool for diagnosis of intermittent cardiovascular symptoms such as syncope and palpitations. Electromagnetic interference in these recorders may be caused by commonly encountered electronic devices such as antitheft electronic surveillance systems and magnetic resonance imaging cameras. In this report, we describe interference in two patients with implantable loop recorders from a portable digital media player.

Characteristics of Telemetry Interference with Pacemakers Caused by Digital Media Players

Background: Contemporary implantable heart rhythm devices communicate multiple complex data simultaneously using radiofrequency telemetry. Interference in communication can expose them to the risk of potential corruption, leading to adverse clinical consequences.

1:1 AV tachycardia: what is the mechanism?

A 53-year-old man with nonischemic cardiomyopathy, left bundle branch block QRS morphology, and congestive heart failure underwent biventricular implantable cardioverter defibrillator (ICD) (Model V365; St. Jude Medical Corporation, Sunnyvale, CA, USA) placement for primary prevention of sudden cardiac death. The device was programmed with two zones: ventricular fibrillation (VF) zone at 210 bpm (285 ms) and ventricular tachycardia (VT) zone at 170 bpm (352 ms). Detection enhancement was programmed on to diagnose VT if any of the discriminators (“Rate Branch,” “Morphology,” and “Sudden Onset”) indicated VT. ICD interrogation during the routine follow-up visit revealed an episode of tachycardia with 1:1 atrioventricular (AV) relationship (Fig. 1). The tachycardia cycle length was initially slightly longer than the VT detection limit and gradually became shorter than VT detection limit. “Rate Branch” and “Sudden Onset” discriminators indicated supraventricular tachycardia (SVT). However, none of eight tachycardia beats matched the template as indicated by the “X” markers. Therefore, VT was detected and successfully terminated by antitachycardia pacing (ATP) therapy. What is the mechanism of the tachycardia?