Natural history of 'silent' atrial fibrillation from subclinical to asymptomatic: State of the art and need for research

Detection of subclinical atrial fibrillation with cardiac implanted electronic devices: What decision making on anticoagulation after the NOAH and ARTESiA trials?

Atrial fibrillation (AF) may be asymptomatic and the extensive monitoring capabilities of cardiac implantable electronic devices (CIEDs) revealed asymptomatic atrial tachi-arrhythmias of short duration (minutes-hours) occurring in patients with no prior history of AF and without AF detection at a conventional surface ECG. Both the terms "AHRE" (Atrial High-Rate Episodes) and subclinical AF were used in a series of prior studies, that evidenced the association with an increased risk of stroke. Two randomized controlled studies were planned in order to assess the risk-benefit profile of anticoagulation in patients with AHRE/subclinical AF: the NOAH and ARTESiA trials. The results of these two trials (6548 patients enrolled, overall) show that the risk of stroke/systemic embolism associated with AHRE/subclinical AF is in the range of 1-1.2 % per patient-year, but with an important proportion of severe/fatal strokes occurring in non-anticoagulated patients. The apparent discordance between ARTESiA and NOAH results may be approached by considering the related study-level meta-analysis, which highlights a consistent reduction of ischemic stroke with oral anticoagulants vs. aspirin/placebo (relative risk [RR] 0.68, 95 % CI 0.50-0.92). Oral anticoagulation was found to increase major bleeding (RR 1.62, 95 % CI 1.05-2.5), but no difference was found in fatal bleeding (RR 0.79, 95 % CI 0.37-1.69). Additionally, no difference was found in cardiovascular death or all-cause mortality. Taking into account these results, clinical decision-making for patients with AHRE/subclinical AF at risk of stroke, according to CHA2DS2-VASc, can now be evidence-based, considering the benefits and related risks of oral anticoagulants, to be shared with appropriately informed patients.

Anticoagulation in Patients with Atrial High-rate Episodes Detected by Cardiac Implantable Electronic Devices

Atrial high-rate episodes (AHRE) are atrial tachyarrhythmias that are identified by the use of continuous rhythm monitoring devices such as pacemakers, defibrillators, or implantable cardiac monitors. Nevertheless, the therapeutic implications of these rhythm disturbances remain uncertain. The presence of AHRE is associated with an increased risk of stroke as compared to patients who do not exhibit AHRE. The utilisation of oral anticoagulation has the ability to mitigate the likelihood of stroke occurrence in patients with AHRE. However, it is important to note that this treatment approach is also linked to a severe bleeding rate of approximately 2% per year. The stroke rate among individuals diagnosed with AHRE appears to be comparatively lower when compared to patients diagnosed with atrial fibrillation. The efficacy and safety of anticoagulation in patients with AHRE have yet to be definitively established. Further research is required to provide a comprehensive understanding of the effectiveness and safety of oral anticoagulation in individuals with AHRE.

Atrial fibrillation and stroke prevention: 25 years of research at EP Europace journal

Stroke prevention in patients with atrial fibrillation (AF) is one pillar of the management of this common arrhythmia. Substantial advances in the epidemiology and associated pathophysiology underlying AF-related stroke and thrombo-embolism are evident. Furthermore, the introduction of the non-vitamin K antagonist oral anticoagulants (also called direct oral anticoagulants) has clearly changed our approach to stroke prevention in AF, such that the default should be to offer oral anticoagulation for stroke prevention, unless the patient is at low risk. A strategy of early rhythm control is also beneficial in reducing strokes in selected patients with recent onset AF, when compared to rate control. Cardiovascular risk factor management, with optimization of comorbidities and attention to lifestyle factors, and the patient's psychological morbidity are also essential. Finally, in selected patients with absolute contraindications to long-term oral anticoagulation, left atrial appendage occlusion or exclusion may be considered. The aim of this state-of-the-art review article is to provide an overview of the current status of AF-related stroke and prevention strategies. A holistic or integrated care approach to AF management is recommended to minimize the risk of stroke in patients with AF, based on the evidence-based Atrial fibrillation Better Care (ABC) pathway, as follows: A: Avoid stroke with Anticoagulation; B: Better patient-centred, symptom-directed decisions on rate or rhythm control; C: Cardiovascular risk factor and comorbidity optimization, including lifestyle changes.

Single-lead VDD pacing: a literature review on short-term and long-term performance

INTRODUCTION

VDD pacing system was introduced more than 30 years ago. Its use is considered by the 2021 European Society of Cardiology guidelines on cardiac pacing as a potential alternative to dual chambers system for patients with atrioventricular block and normal sinus node function.

AREAS COVERED

In this article, we performed a narrative review of current literature in order to identify the strengths and weaknesses of this pacing system. VDD system allows the maintenance of AV synchronous pacing and its hemodynamic advantages. Some disadvantages may be related to the non-negligible incidence of atrial undersensing and the possible subsequent need for upgrade to DDD system. On the other hand, shorter implantation time and lower complications rate may be advantages.

EXPERT OPINION

In the modern pacing era, VDD pacing system struggles to find its own space. However, it may still be considered as a valuable alternative to a dual-chamber pacemaker for selected patients, in specific clinical scenarios.