BACKGROUND—Among patients with implantable pacemakers and defibrillators, subclinical atrial fibrillation (SCAF) is associated with an increased risk of stroke; however, there is limited ...understanding of their temporal relationship.
METHODS AND RESULTS—The Asymptomatic Atrial Fibrillation and Stroke Evaluation in Pacemaker Patients and the Atrial Fibrillation Reduction Atrial Pacing Trial (ASSERT) enrolled 2580 pacemaker and defibrillator patients aged ≥65 years with a history of hypertension but without a history of atrial fibrillation. Pacemakers and implantable cardioverter-defibrillators precisely logged the time and duration of all episodes of SCAF and recorded electrograms that were adjudicated by experts. We examined the temporal relationship between SCAF >6 minutes in duration and stroke or systemic embolism. Of 51 patients who experienced stroke or systemic embolism during follow-up, 26 (51%) had SCAF. In 18 patients (35%), SCAF was detected before stroke or systemic embolism. However, only 4 patients (8%) had SCAF detected within 30 days before stroke or systemic embolism, and only 1 of these 4 patients was experiencing SCAF at the time of the stroke. In the 14 patients with SCAF detected >30 days before stroke or systemic embolism, the most recent episode occurred at a median interval of 339 days (25th to 75th percentile, 211–619) earlier. Eight patients (16%) had SCAF detected only after their stroke, despite continuous monitoring for a median duration of 228 days (25th to 75th percentile, 202–719) before their event.
CONCLUSIONS—Although SCAF is associated with an increased risk of stroke and embolism, very few patients had SCAF in the month before their event.
CLINICAL TRIAL REGISTRATION—URLhttp://www.clinicaltrials.gov. Unique identifierNCT00256152.
Cardiac pacemakers are an extremely effective treatment for bradycardia but can, however, cause desynchronization of ventricular contraction leading to cardiomyopathy. Pacing of the conduction system ...can prevent and even reverse desynchronization, which is impressively visible in echocardiography with speckle tracing. His' bundle and left bundle branch pacing requires a specific implantation technique, sheaths and leads which can achieve successful stimulation of the conduction system in up to 98% of cases. Data on conduction system pacing have been acquired in numerous studies but only a few randomized outcome studies. Therefore, in the current European guidelines His' bundle and left bundle branch pacing only have a low level recommendation. The guidelines recommend His' bundle pacing in patients in whom a coronary sinus lead cannot be implanted and in patients with permanent atrial fibrillation and planned atrioventricular (AV) node ablation for heart rate control. Additionally, conduction system pacing appears to be meaningful in patients with an AV block who require pacing of the ventricle for ≥20% of the time or who already show a slightly or moderately reduced left ventricular ejection fraction (36-50%). Even in patients scheduled for generator replacement who have developed a cardiac pacemaker-induced cardiomyopathy, the opportunity should not be missed to upgrade the system by implantation of a His' bundle electrode.
Subclinical Atrial Fibrillation and the Risk of Stroke Healey, Jeff S; Connolly, Stuart J; Gold, Michael R ...
New England journal of medicine/The New England journal of medicine,
01/2012, Letnik:
366, Številka:
2
Journal Article
Recenzirano
Odprti dostop
A cohort of 2580 patients with pacemakers or defibrillators were monitored for 3 months to detect subclinical atrial tachyarrhythmias. Patients with subclinical atrial tachyarrhythmias had a ...significantly increased risk of subsequent ischemic stroke.
Atrial fibrillation may be asymptomatic and consequently subclinical.
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Epidemiologic studies indicate that many patients with atrial fibrillation on screening electrocardiograms had not previously received a diagnosis of atrial fibrillation.
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About 15% of strokes are attributable to documented atrial fibrillation, and 50 to 60% to documented cerebrovascular disease,
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but in about 25% of patients who have ischemic strokes, no etiologic factor is identified.
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Subclinical atrial fibrillation is often suspected to be the cause of stroke in these patients.
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However, the prevalence and prognostic value of subclinical atrial fibrillation has been difficult to assess.
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An . . .
Zusammenfassung
Herzschrittmacher stellen eine extrem effektive Therapie von Bradykardien dar, können jedoch über eine Desynchronisation der ventrikulären Kontraktion eine Kardiomyopathie ...verursachen. Die Stimulation des Leitungssystems kann diese Desynchronisation verhindern und rückgängig machen, was echokardiographisch im „speckle tracking“ eindrucksvoll sichtbar wird. His-Bündel- und Linksschenkelstimulation erfordern eine spezielle Implantationstechnik, Schleusen und Elektroden, wodurch eine erfolgreiche Stimulation des Leitungssystems in bis zu 98 % der Fälle erreicht werden kann. Bislang liegen zahlreiche Studiendaten, jedoch nur wenige randomisierte Outcome-Studien vor. In den aktuellen europäischen Leitlinien ist die His-Bündel‑/Linksschenkelstimulation daher nur mit einem geringen Empfehlungsgrad versehen. In den Leitlinien wird die His-Bündel-Stimulation für Patienten, bei denen keine Koronarsinuselektrode implantiert werden kann, und für Patienten mit permanentem Vorhofflimmern, bei denen eine Atrioventrikular(AV)-Knoten-Ablation zur Frequenzkontrolle geplant ist, empfohlen. Darüber hinaus erscheint sie sinnvoll für Patienten mit AV-Blockierungen, bei denen die Notwendigkeit besteht, den Ventrikel für 20 % der Zeit oder länger zu stimulieren, oder die bereits eine leicht- bis mittelgradig reduzierte linksventrikuläre Ejektionsfraktion (36–50 %) zeigen. Auch bei Patienten, bei denen sich zum Zeitpunkt des Aggregatwechsels eine schrittmacherinduzierte Kardiomyopathie zeigt, sollte die zusätzliche Implantation einer His-Bündel-Elektrode erwogen werden.
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