Auto-entrainment risk assessment in heart failure.

Background: Risk assessment studies use a suite of nominally independent noninvasive heart rate metrics, often brought together in a statistical model to compute a risk score. The ongoing need to noninvasively identify the higher risk patients requiring more invasive investigations/interventions drives the search for better noninvasive predictive metrics, with increased sensitivity. Many varieties of autoregulatory malfunction occur within the cardiovascular system; thus, it seems a daunting challenge to build predictive models that account for all potential modes of failure.

Impact of atrial antitachycardia pacing and atrial pace prevention therapies on atrial fibrillation burden over long-term follow-up.

Aims: Selective atrial pacing algorithms have been developed for prevention of atrial tachycardia/atrial fibrillation (AT/AF). Although short-term studies have shown modest to minimal incremental benefit of these algorithms compared with conventional dual-chamber (DDD/R) pacing for prevention of AT/AF, the long-term effects of these algorithms are unknown. Accordingly, we compared atrial antitachycardia pacing (ATP) therapy and combined atrial ATP and atrial pace prevention (ATP + Prevention) algorithms to conventional DDD/R pacing for prevention of AT/AF over long-term follow-up.

Beneficial effects of statin therapy for prevention of atrial fibrillation following DDDR pacemaker implantation.

Aims: Data suggest that atrial pacing, statins, angiotensin-converting enzyme-inhibitors and angiotensin receptor blocking drugs prevent atrial tachycardia/atrial fibrillation (AT/AF) in some patients. The clinical predictors of at/af recurrence following dual-chamber pacemaker insertion were examined in 185 consecutive patients with paroxysmal AF.

Methods And Results: Predictors of AT/AF recurrence were evaluated in this observational cohort study.

High atrial antitachycardia pacing therapy efficacy is associated with a reduction in atrial tachyarrhythmia burden in a subset of patients with sinus node dysfunction and paroxysmal atrial fibrillation.

Background: Atrial tachycardia (AT) and atrial flutter that occur in association with paroxysmal atrial fibrillation (AF) can be successfully terminated by antitachycardia pacing (ATP) therapy. We hypothesized that atrial ATP therapy reduces AT/AF burden in a subset of patients with symptomatic bradycardia and frequent paroxysmal AT/AF.

Objectives: This study evaluated the effect of atrial ATP therapy on AT/AF burden in a pacemaker population with paroxysmal AF.

Ventricular high-rate episodes in pacemaker diagnostics identify a high-risk subgroup of patients with tachy-brady syndrome.

Objectives: The purpose of this study was to evaluate the frequency and clinical significance of ventricular high-rate (VHR) episodes (ventricular rate >162 bpm) in patients with symptomatic bradycardia and paroxysmal atrial fibrillation (AF).

Background: Newer pacemakers have enhanced diagnostic features that permit detection and storage of detailed information about the frequency, duration, and time of onset of multiple episodes of AF, atrial tachycardia (AT), and ventricular tachycardia (VT). However, the prevalence and prognostic value of AF associated with rapid ventricular rates in the pacemaker population are unknown.

Randomized controlled trial of fixed rate versus rate responsive pacing after radiofrequency atrioventricular junction ablation: quality of life, ventricular refractoriness, and paced QT dispersion.

Introduction: Ablation of the AV junction is a widely accepted treatment of drug-refractory atrial fibrillation. Long-term pacing of the right ventricular (RV) apex following AV junction ablation can result in adverse cardiac remodeling. However, anecdotal studies report that pacing too slowly following AV junction ablation was associated with propensity to sudden cardiac death.

Paced QT dispersion and QT morphology after radiofrequency atrioventricular junction ablation: impact of left ventricular function.

Catheter ablation of the atrioventricular junction (AVJ) is a widely accepted treatment for drug refractory atrial fibrillation. Unfortunately, there have been some reports of pause dependent ventricular arrhythmias associated with QT interval prolongation, mainly in patients with reduced LV function. The present investigation evaluates the association of LV function with QT dispersion in response to a sudden rate drop.

Antitachycardia pacing therapies and arrhythmia monitoring diagnostics for the treatment of atrial fibrillation.

The case of a patient with frequent episodes of atrial fibrillation that organizes into atrial flutter following implantation of a dual chamber, rate adaptive pacemaker is reported. The atrial flutter was effectively pace-terminated following activation of the atrial antitachycardia pacing therapies in the pacemaker. This resulted in a decrease in atrial fibrillation burden over time.

Atrial fibrillation after DDDR pacemaker implantation.

Introduction: Newer implantable pulse generators have data storage capabilities that permit detection of multiple episodes of atrial fibrillation (AF). This study evaluated the clinical predictors and time course of AF development in a general pacemaker population.

Methods And Results: Patients (n = 231) received DDDR pacemakers with features that permit detection and storage of information about the date, time of onset, and duration of multiple, sequential episodes of AF.