Efficacy Of Atrial Antitachycardia Pacing Research Articles

P5655Efficacy of new-generation atrial antitachycardia pacing for atrial tachyarrhythmias in patients with left ventricular dysfunction

Abstract Background The progression to persistent atrial fibrillation (AF) is associated with a worse clinical outcome in patients with previous atrial tachyarrhythmias. New-generation atrial antitachycardia pacing (ATP) (Reactive ATP) reduced the progression to persistent AF in patients with pacemaker and preserved left ventricular (LV) function. However, little is known about the efficacy of Reactive ATP in patients with cardiac implantable electronic devices (CIED) and LV dysfunction. Purpose We aimed to investigate the efficacy of Reactive ATP for atrial tachyarrhythmias in patients with LV dysfunction (LV ejection fraction [LVEF] <40%). Methods This study included 423 patients with CIED and previous atrial tachyarrthythmias. Reactive ATP was programmed in 284 patients (ATP group) and 139 were implanted with a dual-chamber device without ATP function (control group). The differences in the success rate of ATP and incidence of progression to persistent AF (≥7 days) between the ATP and control groups were evaluated in 108 patients with LVEF <40% (reduced LVEF) and 315 with LVEF ≥40% (preserved LVEF). Patients with persistent AF were excluded from this study. Results During 710±337 days of follow-up period, 16 patients (15%) with reduced LVEF and 51 (16%) with preserved LVEF progressed to persistent AF (p=0.88). The mean ATP success rate was lower in patients with reduced LVEF than in those with preserved LVEF, although not statistically significant (reduced LVEF: 27.2±19.4% and preserved LVEF: 35.1±29.2%, p=0.12). The incidence of progression to persistent AF was significantly lower in the ATP group than in the control group both in patients with reduced and preserved LVEF (log-rank, reduced LVEF: p=0.0070 and preserved LVEF: p<0.0001) (Figure). Multivariate analysis showed that use of Reactive ATP and smaller left atrium were associated with lower incidences of persistent AF, while LVEF was not predictive of progression to persistent AF (Reactive ATP: hazard ratio [HR] 0.28, 95% confidence interval [CI] 0.17–0.46, p<0.0001, left atrium diameter: HR 1.03, 95% CI 1.00–1.07, p=0.030). Figure 1 Conclusions Reactive ATP was effective in preventing AF progression in patients with LV dysfunction.

1355Real-world observational data confirm the efficacy of atrial antitachycardia pacing in terminating slow and regular atrial tachyarrhythmias in patients wearing implantable cardiac electronic devices

1355Real-world observational data confirm the efficacy of atrial antitachycardia pacing in terminating slow and regular atrial tachyarrhythmias in patients wearing implantable cardiac electronic devices

P894Real-world observational data confirm the efficacy of atrial antitachycardia pacing in terminating slow and regular atrial tachyarrhythmias in patients wearing implantable cardiac electronic devices

P894Real-world observational data confirm the efficacy of atrial antitachycardia pacing in terminating slow and regular atrial tachyarrhythmias in patients wearing implantable cardiac electronic devices

Safety and efficacy of atrial antitachycardia pacing in congenital heart disease

Intra-atrial reentrant tachycardia (IART) is a common sequela in the congenital heart disease (CHD) population, and it significantly increases morbidity and mortality. Atrial antitachycardia devices (ATDs) capable of atrial antitachycardia pacing (ATP) therapy have been used to manage IART in the CHD population, but there are limited data on their safety and efficacy. To determine whether ATD implantation was associated with reduced direct current (DC) cardioversions and to compare ATP success between different CHD diagnoses and ATP programs. A single-center retrospective chart review was performed on CHD patients with ATDs. Demographic data were collected in addition to the number of DC cardioversions required before and after ATD implantation; data on ATP efficacy and the specific ATP program utilized; and adverse events related to ATD implantation or subsequent ATP treatments. ATD implantation in 91 CHD patients was associated with a significant reduction in DC cardioversions (P < .01). Overall, 72% of IART episodes were successfully terminated by ATP. Patients with levo-transposition of the great arteries experienced lower rates of ATP success than the remainder of the cohort (P < .01). There was no evidence of degeneration to ventricular arrhythmia or death directly attributed to ATP. ATD implantation was associated with reduced DC cardioversion burden. Patients with levo-transposition of the great arteries may experience lower ATP efficacy than patients with other CHDs; however, a larger patient population is required to better determine subgroup efficacy. These results support the safety and efficacy of ATP in the CHD population.

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

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. This study evaluated the effect of atrial ATP therapy on AT/AF burden in a pacemaker population with paroxysmal AF. We compared AT/AF burden in 261 patients who received a Medtronic AT500 pacemaker for treatment of AT/AF in the setting of symptomatic bradycardia based on device-classified atrial ATP efficacy < 60% and > or = 60%. Patients with > or = 10 device-detected episodes of AT/AF before and after atrial ATP therapy initiation were identified from four clinical studies performed in 72 centers worldwide. The high efficacy group comprised 75 patients with atrial ATP efficacy > or = 60%. The low efficacy group comprised 186 patients with atrial ATP efficacy < 60%. AT/AF episode frequency was similar in both groups prior to ATP activation and decreased in the low efficacy group following ATP activation. Following atrial ATP initiation, total AT/AF burden increased slightly in the low ATP efficacy group (median 2.77 [25th-75th percentiles 0.84-5.86] hours/day vs 2.92 [0.59-8.12] hours/day, P = .01). In contrast, total AT/AF burden decreased significantly in the high efficacy group (median 2.46 [0.29-8.88] hours/day vs 0.68 [0.13-2.97] hours/day, P < .001). Up to 30% of patients with frequent episodes of paroxysmal AF and symptomatic bradycardia experience a reduction in AT/AF burden from atrial ATP therapy over time.

711 Predictors of atrial antitachycardia pacing efficacy in patients affected by brady-tachy form of sick sinus syndrome and implanted with a DDDRP device

711 Predictors of atrial antitachycardia pacing efficacy in patients affected by brady-tachy form of sick sinus syndrome and implanted with a DDDRP device

711 Predictors of atrial antitachycardia pacing efficacy in patients affected by brady-tachy form of sick sinus syndrome and implanted with a DDDRP device

711 Predictors of atrial antitachycardia pacing efficacy in patients affected by brady-tachy form of sick sinus syndrome and implanted with a DDDRP device

Comparison of immediate and delayed automatic antitachycardia pacing for the termination of atrial tachyarrhythmias

Automatic atrial antitachycardia pacing (ATP) can terminate atrial tachyarrhythmias (ATs) in patients with an implanted device. We investigated if the programmable delay between AT onset and ATP influences therapy efficacy. Patients with intermittent ATs and an implanted DDDRP pacemaker were randomized to receive ATP either immediately or 30min after AT detection. After four months stored data were interrogated, AT-related symptoms were assessed, and patients crossed over to the alternative treatment arm for another four months. Stored atrial electrograms were analyzed for degree of AT organization and ATP success. In 22 patients (64% male; 72+/-7 years), ATP success rates were higher during immediate than during delayed ATP (device classification: 59+/-7% vs. 22+/-5%, P<0.01; manual analysis: 36+/-6% vs. 12+/-5%, P<0.01). Higher efficacy of immediate ATP was associated with a larger proportion of organized (Type I) AT prior to therapy (71% vs. 44% during delayed ATP). No difference was found in total AT numbers and duration, AT burden or related symptoms. The programmable delay between arrhythmia onset and therapy delivery significantly influences the success-rate of ATP. However, a higher efficacy of immediate compared with delayed ATP does not translate into a reduction of AT burden or related symptoms.

1091-225 Atrial antitachycardia pacing efficacy based on time and rhythm

1091-225 Atrial antitachycardia pacing efficacy based on time and rhythm

P-031 efficacy of atrial antitachycardia pacing for termination of atrial tachyarrythmias

P-031 efficacy of atrial antitachycardia pacing for termination of atrial tachyarrythmias

Efficacy of atrial antitachycardia pacing using the Medtronic AT500 pacemaker in patients with congenital heart disease

Patients with congenital heart disease are vulnerable to atrial tachyarrhythmias, especially after atrial surgeries. We evaluated the efficacy of atrial arrhythmia detection and antitachycardia pacing (ATP) using the Medtronic AT500 pacemaker in 28 patients with congenital heart disease (age 30 ± 18 years). Of 15 patients with atrial arrhythmias, 14 had atrial tachycardia events that were appropriately detected. ATP was enabled for 167 treatable episodes, successfully converting 90 (54%). Rhythms classified as ventricular tachycardia were detected 127 times, yet most were actually atrial or sinus tachycardia with 1:1 atrioventricular conduction. Atrial tachycardias in congenital heart disease are amenable to ATP alogorithms in the AT500 pacemaker.

Safety and efficacy of advanced atrial pacing therapies for atrial tachyarrhythmias in patients with a new implantable dual chamber cardioverter-defibrillator

ObjectivesThis study evaluated the safety and efficacy of atrial pacing therapies for the treatment and prevention of atrial tachycardia (AT) or atrial fibrillation (AF) in a new dual chamber implantable cardioverter defibrillator (ICD). BackgroundPatients with an ICD may also experience AT or AF that is amenable to pace termination. MethodsThe efficacy of atrial antitachycardia pacing (ATP) therapies for atrial tachycardia or atrial fibrillation (AT/AF) was determined in 151 patients after implantation of a GEM III AT ICD (Medtronic Inc., Minneapolis, Minnesota). The percentage of episodes successfully terminated was adjusted for multiple episodes per patient. ResultsA total of 717 of 728 (96%) episodes classified as AT or AF were judged to be appropriate detections. By device classification, atrial ATP terminated 187 of 383 (40% adjusted) episodes classified as AT compared with 65 of 240 episodes classified as AF (26% adjusted, p = 0.013). Atrial Ramp or Burst+ ATP terminated 184 of 378 episodes of AT (39% adjusted), whereas 50-Hz Burst pacing therapy terminated only 12 of 109 episodes of AT (12% adjusted) and 65 of 240 episodes of AF (26% adjusted). If efficacy was defined as termination of AT/AF within 20 s of delivery of the pacing therapy, ATP therapies terminated 139 of 383 (32% adjusted) episodes of AT compared with 34 of 240 episodes of AF (15% adjusted, p = 0.003). Efficacy was dependent on AT cycle length. Frequent transitions between AT and AF predicted inefficacy of atrial ATP (p < 0.001). Ventricular proarrhythmia secondary to atrial ATP was not observed. ConclusionsAtrial ATP therapies terminate many episodes of AT without ventricular proarrhythmia. The addition of 50-Hz Burst pacing has minimal efficacy for AT/AF.

Antitachycardia pacing therapy to treat spontaneous atrial tachyarrhythmias: the 7250 dual defibrillator Italian Registry

Background The dual defibrillator is a new device that can deliver atrial antitachycardia pacing (ATP) and shock therapies to treat atrial tachyarrhythmias in patients with and without life-threatening ventricular tachyarrhythmias. The aims of the present study were to investigate the efficacy of ATP and to identify factors that may impact on success of treatment. Method A total of 105 patients (80 male, mean age 64 ± 10 years) implanted with a dual defibrillator were enrolled in the study; 66% had documented atrial fibrillation (AF) before implantation a nd 14% had no history of prior ventricular tachyarrhythmias.

Worldwide clinical experience with a new dual-chamber implantable cardioverter defibrillator system.

Management of atrial tachyarrhythmias represents a significant challenge in patients with implantable cardioverter defibrillators (ICDs). Drug therapy of these arrhythmias is limited by moderate efficacy, ventricular proarrhythmia, and drug-device interactions. This study tested the safety and efficacy of a new dual-chamber ICD to detect and treat atrial as well as ventricular tachyarrhythmias. A dual-chamber ICD (Medtronic 7250 Jewel AF) was implanted in 293 of 303 patients at 49 centers in Europe, Canada, and North America. Specific data were collected at implant and during a mean follow-up period of 7.9+/-4.7 months. There were no clinically evident failures to detect and treat ventricular arrhythmias. In patients with at least one of the dual-chamber detection criteria activated, 1,056 of 1,192 episodes of ventricular tachycardia or fibrillation detected were judged to be appropriate (89% positive predictive accuracy). Therapy efficacy was 100% in the ventricular fibrillation zone and 98% in the ventricular tachycardia zone. Positive predictive accuracy for detection of atrial episodes was 95% (1,052/1,107). For episodes classified as atrial tachycardia by the device, the efficacy of atrial antitachycardia pacing and high-frequency (50-Hz) burst pacing was 55% and 17%, respectively. High-frequency burst pacing terminated 16.8% of episodes classified as atrial fibrillation, and atrial defibrillation had an estimated efficacy of 76%. The actuarial estimates of 6-month complication-free survival and total survival were 88% and 94%, respectively. This novel dual-chamber ICD is capable of safely and effectively discriminating atrial from ventricular tachyarrhythmias and of treating atrial tachyarrhythmias without compromising detection and treatment of ventricular tachyarrhythmias.