James P. Daubert

Multicenter Automatic Defibrillator Implantation Trial–Cardiac Resynchronization Therapy (MADIT‐CRT): Design and Clinical Protocol

The planned MADIT‐CRT trial is designed to determine if CRT‐D will reduce the risk of mortality and HF events by approximately 25% in subjects with ischemic (NYHA class I‐II) and non‐ischemic (NYHA class II) cardiomyopathy, left ventricular dysfunction (EF ≤ 0.30), and prolonged intraventricular conduction (QRS duration ≥ 130 ms).

Initial independent outcomes from focal impulse and rotor modulation ablation for atrial fibrillation: multicenter FIRM registry.

The success of pulmonary vein isolation (PVI) for atrial fibrillation (AF) may be improved if stable AF sources identified by Focal Impulse and Rotor Mapping (FIRM) are also eliminated. The long‐term results of this approach are unclear outside the centers where FIRM was developed; thus, we assessed outcomes of FIRM‐guided AF ablation in the first cases at 10 experienced centers.

Safety and Efficacy of Flecainide in Subjects with Long QT‐3 Syndrome (ΔKPQ Mutation): A Randomized, Double‐Blind, Placebo‐Controlled Clinical Trial

Background: We conducted a study of chronic therapy with flecainide versus placebo in a small group of LQT‐3 patients with the ΔKPQ deletion to evaluate the safety and efficacy of flecainide in this genetic disorder. In vitro studies have shown that flecainide provides correction of the impaired inactivation associated with the ΔKPQ deletion.

Stability of rotors and focal sources for human atrial fibrillation: focal impulse and rotor mapping (FIRM) of AF sources and fibrillatory conduction.

Several groups report electrical rotors or focal sources that sustain atrial fibrillation (AF) after it has been triggered. However, it is difficult to separate stable from unstable activity in prior studies that examined only seconds of AF. We applied phase‐based focal impulse and rotor mapping (FIRM) to study the dynamics of rotors/sources in human AF over prolonged periods of time.

End‐of‐Life Care in Patients with Implantable Cardioverter Defibrillators: A MADIT‐II Substudy

Implantable cardioverter defibrillator (ICD)‐delivered shocks can cause substantial distress, warranting consideration of ICD deactivation at end of life. This study was designed to describe the patterns of end‐of‐life management in patients with ICDs.

Catheter ablation for ventricular tachycardia in patients with an implantable cardioverter defibrillator (CALYPSO) pilot trial.

We conducted this pilot randomized clinical trial to determine the feasibility of a large clinical trial aimed at testing whether early use of catheter ablation of ventricular tachycardia (VT) is superior to antiarrhythmic medications at reducing mortality.

Impact of using a telescoping-support catheter system for left ventricular lead placement on implant success and procedure time of cardiac resynchronization therapy.

Proper positioning of the left ventricular (LV) lead improves clinical outcomes and survival in patients receiving cardiac resynchronization therapy (CRT). Techniques of LV lead insertion using contrast injection and a telescoping system of delivery catheters to support advancement of the lead into the target branch may allow more efficient, targeted lead placement. We sought to evaluate the impact of an LV lead implant approach using telescoping‐support catheters (group TS) on success rate, lead location, and procedural time compared to standard over‐the‐wire implant techniques (group OTW).

ECG Quantification of Myocardial Scar and Risk Stratification in MADIT‐II

Low left ventricular ejection fraction (LVEF) increases risk for both sudden cardiac death (SCD) and for heart failure (HF) death; however, implantable cardioverter‐defibrillators (ICDs) reduce the incidence of SCD, not HF death. Distinguishing individuals at risk for HF death (non‐SCD) versus SCD could improve ICD patient selection.

Preprocedural ECG‐Gated Computed Tomography for Prevention of Complications during Lead Extraction

Preprocedural multidetector computed tomography (MDCT) may identify patients at risk for mechanical complications during lead extraction.

Adverse Effects of First‐Degree AV‐Block in Patients with Sinus Node Dysfunction: Data from the Mode Selection Trial

Patients with a pacing indication and first‐degree atrioventricular (AV)‐block pose a clinical challenge. The prognostic impact of first‐degree AV‐block in patients with sinus node dysfunction and the impact of pacing in this setting are not known.