Abstract
Introduction and objectives: Since physiological pacing systems have become available, a debate has raged about the merits of atrial versus ventricular pacing in the sick sinus syndrome. The goal of this retrospective report was to study the long term incidence and the independent predictors for atrial fibrillation and stroke in 153 paced patients with sick sinus syndrome, adjusting for differences in baseline clinical variables with multivariate analysis.
Method and results: From 1980 to 1994, we implanted 32 dualchamber, 33 atrial, and 88 ventricular pacemakers to treat patients with sick sinus syndrome. After a maximum follow-up of 177 months (median 30 months for paroxismal atrial fibrillation, 45 months for chronic atrial fibrillation and 43,5 months for stroke) the actuarial incidence of paroximal atrial fibrillation was 7.8% at 1 year, 29% at 5 years and 42% at 10 years. The actuarial incidence of chronic atrial fibrillation was 1.3% at 1 year, 9.8% at 5 years and 22% at 10 years. Independent predictors for paroxismal AF from Cox's model was history of atrial tachyarrhythmias (p < 0.0001), chronic obstructive pulmonary disease (p = 0,006) and age (> 70 years-old) (p = 0.035). Only a history of atrial tachyarrhythmias before pacemaker implant was an independent predictor for chronic atrial fibrillation (p < 0.0001). The odd ratio for paroxismal atrial fibrillation in patients with previous atrial tachyarrhythmias and chronic atrial fibrillation were 6 (2.8-12) and 4 (1.6-9.7) (95% confiance limits). Actuarial incidence of stroke was 3% at 1 year, 10% at 5 years and 14% at 10 years. Independent predictors for stroke were history of peripheral vascular disease (p = 0.033) and hypertensive cardiomyopathy (p = 0.015). Development of paroxysmal and chronic atrial fibrillation during the follow-up were higher in patients with stroke (p < 0.001 and p < 0.05).
Conclusions: Development of atrial fibrillation and stroke in paced patients with sick sinus syndrome are strongly determined by clinical variables. Preimplant paroxysmal atrial tachyarrhythmias is the most important predictor for atrial fibrillation in the follow-up.*1
Abstract
Several studies reported that the annual incidence of stroke in patients with sick sinus syndrome ranges from 6 to 10% while the incidence of stroke in patients with atrial fibrillation is about 2-4% and about 0.1% in the normal population. We evaluated the prevalence of cerebral ischemia and peripheral embolism and investigated the predictor factors in a population of 80 patients paced for sick sinus syndrome. The implanted pacemakers were 40 ventricular and 40 physiological stimulation mode was based on the physicians judgement. All patients had cerebral computed tomography scan at the time of implant and after 24 months. Statistical analysis included log-rank test and actuarial curve calculated with Mantel-Haenszel method. At the end of follow-up the end-point occurred in 15 patients: 2 patients had asymptomatic cerebral infarction, 2 had fatal stroke, 2 developed peripheral embolysm, 1 to the lower limb and 1 abdominal; in 4 patients a transient ischemic attack occurred, in 2 a minor stroke and in 3 a non invalidant stroke. No statistically significant difference was found among the subgroups; with different pacing modality. In conclusion, multivariate analysis underlines the role of age > 65 years, history of cerebral ischemia, low atrial ejection force and spontaneous echo contrast in the development of embolic episodes.*2
Abstract
Sinus node disease (SND), a common indication to implant a pacemaker, is frequently associated with atrial fibrillation (AF), either at implantation (paroxysmal AF) or during follow-up, which often evolves to persistent or permanent AF. Pacemakers with an atrial lead allow continuous monitoring of the atrial rhythm and enable detection of the burden of AF. Asymptomatic atrial tachyarrhythmias, being associated with increased risk of stroke, have important prognostic implications, and their detection could guide decision-making about antithrombotic prophylaxis. Pacing mode and pacing algorithms can influence the occurrence of AF and atrial tachyarrhythmias. In DDD/DDDR pacing mode, reduction of unnecessary right ventricular pacing positively affects the occurrence and evolution of AF, but patients with a history of atrial tachyarrhythmias maintain an increased risk of arrhythmic events. In the MINERVA study, the use of algorithms that act in the atrium for preventive pacing and atrial antitachycardia pacing while minimizing right ventricular pacing was beneficial in patients with SND and previous atrial tachyarrhythmias, and was associated with a significant reduction in evolution to permanent AF. New information available on therapies delivered at the atrial level by implanted devices suggests clinical advantages that could improve current guidelines for the management of AF and atrial tachyarrhythmias.*3
Abstract
Purpose of review: The goal of this paper is to review present knowledge regarding preventive and antitachycardia pacing algorithms, aimed to reduce atrial fibrillation (AF) burden in patients when pacing is indicated.
Recent findings: Reactive antitachycardia pacing (ATP), the new generation of ATP, is significantly associated with a reduced risk of AF. In patients with indication for pacing and history of AF, pacemakers endowed with atrial preventive pacing and atrial ATP combined with managed ventricular pacing proved superior to standard dual-chamber pacing. Managed ventricular pacing is an algorithm that minimizes unnecessary right ventricular pacing. Progression to persistent AF is prevented by ventricular pacing minimization in patients with normal PR interval. The synergistic effect of pacemakers that combine atrial preventive pacing with reactive ATP and with algorithms that minimize ventricular pacing can reduce AF incidence and decrease the combined endpoint of permanent AF, hospital admissions, and mortality.
Keywords: Antitachycardia pacing; Atrial fibrillation; Atrial pacing therapies; Pacing minimization algorithms. *4
Abstract
Background: Atrial fibrillation (AF) is a frequent comorbidity in patients with pacemaker and is a recognized cause of mortality, morbidity, and quality-of-life impairment. The international MINimizE Right Ventricular pacing to prevent Atrial fibrillation and heart failure trial established that atrial preventive pacing and atrial antitachycardia pacing (DDDRP) in combination with managed ventricular pacing (MVP) reduce permanent AF occurrence in comparison with standard dual-chamber pacing (DDDR).
Objective: We aimed to determine the role of new-generation atrial antitachycardia pacing (Reactive ATP) in preventing AF disease progression.
Methods: Patients with dual-chamber pacemaker and with previous atrial tachyarrhythmias were randomly assigned to DDDR (n = 385 (33%)), MVP (n = 398 (34%)), or DDDRP+MVP (n = 383 (33%)) group. The incidence of permanent AF, as defined by the study investigator, or persistent AF, defined as ≥7 consecutive days with AF, was estimated using the Kaplan-Meier method, while its association with patients' characteristics was evaluated via multivariable Cox regression.
Results: At 2 years, the incidence of permanent or persistent AF was 26% (95% confidence interval [CI] 22%-31%) in the DDDR group, 25% (95% CI 21%-30%) in the MVP group, and 15% (95% CI 12%-20%) in the DDDRP+MVP group (P < .001 vs. DDDR; P = .002 vs. MVP). Generalized estimating equation-adjusted Reactive ATP efficacy was 44.4% (95% CI 41.3%-47.6%). Multivariate modeling identified high Reactive ATP efficacy (>44.4%) as a significant predictor of reduced permanent or persistent AF risk (hazard ratio 0.32; 95% CI 0.13-0.781; P = .012) and episodes' characteristics, such as long atrial arrhythmia cycle length, regularity, and the number of rhythm transitions, as predictors of high ATP efficacy.
Conclusion: In patients with bradycardia, DDDRP+MVP delays AF disease progression, with Reactive ATP efficacy being an independent predictor of permanent or persistent AF reduction.
Keywords: Antitachycardia pacing; Atrial fibrillation; Pacemaker; Reactive ATP. *5
*1Auricular fibrillation and stroke in patients with sick sinus syndromeusing permanent pacemakers]
[Article in Spanish]
R Sanjuán Máñez et al. Rev Esp Cardiol. 1996 Jul.
*2Stroke in pacemaker users for sinus disease. Relevance of atrial function and clinical characteristics].
*3Management of atrial fibrillation in bradyarrhythmias
Giuseppe Boriani et al. Nat Rev Cardiol. 2015 Jun.
*4 Programming Pacemakers to Reduce and Terminate Atrial Fibrillation
Margarida Pujol-López et al. Curr Cardiol Rep. 2019.
*5New-generation atrial antitachycardia pacing (Reactive ATP) is associated with reduced risk of persistent or permanent atrial fibrillation in patients with bradycardia: Results from the MINERVA randomized multicenter international trial
Luigi Padeletti et al. Heart Rhythm. 2015 Aug.
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