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Cardiac Electrophysiology Clinics Dec 2021Delayed atrioventricular (AV) conduction most commonly occurs in the AV node, resulting from AH prolongation on an intracardiac electrocardiogram and PR prolongation on... (Review)
Review
Delayed atrioventricular (AV) conduction most commonly occurs in the AV node, resulting from AH prolongation on an intracardiac electrocardiogram and PR prolongation on a surface electrocardiogram. AV conduction may be blocked in a 2:1 manner, with a normal PR interval and wide QRS suggesting infranodal disease, whereas a prolonged PR interval and narrow QRS are more suggestive of AV nodal disease. Block within the His is suspected when there is 2:1 AV block with normal PR and QRS intervals. Complete heart block occurs when the atrial rhythm is totally independent of a junctional or lower escape rhythm.
Topics: Atrioventricular Block; Atrioventricular Node; Electrocardiography; Humans
PubMed: 34689889
DOI: 10.1016/j.ccep.2021.07.001 -
Trends in Cardiovascular Medicine Jul 2020Bradycardia is a commonly observed arrhythmia and a frequent occasion for cardiac consultation. Defined as a heart rate of less than 50-60 bpm, bradycardia can be... (Review)
Review
Bradycardia is a commonly observed arrhythmia and a frequent occasion for cardiac consultation. Defined as a heart rate of less than 50-60 bpm, bradycardia can be observed as a normal phenomenon in young athletic individuals, and in patients as part of normal aging or disease (Table 1). Pathology that produces bradycardia may occur within the sinus node, atrioventricular (AV) nodal tissue, and the specialized His-Purkinje conduction system. Given the overlap of heart rate ranges with non-pathologic changes, assessment of symptoms is a critical component in the evaluation and management of bradycardia. Treatment should rarely be prescribed solely on the basis of a heart rate lower than an arbitrary cutoff or a pause above certain duration. In the 2018 ACC/AHA/HRS Guideline on the Evaluation and Management of Patients with Bradycardia and Cardiac Conduction Delay (referred to hereafter as the 2018 Bradycardia Guideline), there was a significant shift in emphasis from prior guidelines that emphasized device-based implantation recommendations to a focus on evaluation and management of disease states [1,2]. In this review, we will highlight the changes in the new guideline as well as describe the key elements in evaluation and management of patients presenting with bradycardia.
Topics: Action Potentials; Atrioventricular Block; Bradycardia; Cardiac Pacing, Artificial; Clinical Decision-Making; Heart Conduction System; Heart Rate; Humans; Pacemaker, Artificial; Patient Selection; Sick Sinus Syndrome; Treatment Outcome
PubMed: 31311698
DOI: 10.1016/j.tcm.2019.07.001 -
Journal of Cardiovascular... Oct 2022Catheter-based cardioneuroablation is increasingly being utilized to improve outcomes in patients with vasovagal syncope and atrioventricular block due to vagal... (Review)
Review
Catheter-based cardioneuroablation is increasingly being utilized to improve outcomes in patients with vasovagal syncope and atrioventricular block due to vagal hyperactivity. There is now increasing convergence among enthusiasts on its various aspects, including patient selection, technical steps, and procedural end-points. This pragmatic review aims to take the reader through a step-by-step approach to cardioneuroablation: we begin with a brief overview of the anatomy of intrinsic cardiac autonomic nervous system, before focusing on the indications, preprocedure and postprocedure management, necessary equipment, and its potential limitations.
Topics: Atrioventricular Block; Catheter Ablation; Heart; Humans; Syncope, Vasovagal; Vagus Nerve
PubMed: 35362165
DOI: 10.1111/jce.15480 -
Cardiology Clinics Aug 2023Congenital complete heart block (CCHB) defines atrioventricular conduction abnormalities diagnosed in utero or within the first 27 days of life. Maternal autoimmune... (Review)
Review
Congenital complete heart block (CCHB) defines atrioventricular conduction abnormalities diagnosed in utero or within the first 27 days of life. Maternal autoimmune disease and congenital heart defects are most commonly responsible. Recent genetic discoveries have highlighted our understanding of the underlying mechanism. Hydroxychloroquine shows promise in preventing autoimmune CCHB. Patients may develop symptomatic bradycardia and cardiomyopathy. The presence of these and other specific findings warrants placement of a permanent pacemaker to relieve symptoms and prevent catastrophic events. The mechanisms, natural history, evaluation, and treatment of patients with or at risk for CCHB are reviewed.
Topics: Humans; Heart Block; Pacemaker, Artificial; Heart Defects, Congenital; Atrioventricular Block
PubMed: 37321690
DOI: 10.1016/j.ccl.2023.03.002 -
Cardiology Clinics Aug 2023Iatrogenic atrioventricular (AV) block can occur in the context of cardiac surgery, percutaneous transcatheter, or electrophysiologic procedures. In cardiac surgery,... (Review)
Review
Iatrogenic atrioventricular (AV) block can occur in the context of cardiac surgery, percutaneous transcatheter, or electrophysiologic procedures. In cardiac surgery, patients undergoing aortic and/or mitral valve surgery are at the highest risk for developing perioperative AV block requiring permanent pacemaker implantation. Similarly, patients undergoing transcatheter aortic valve replacement are also at increased risk for developing AV block. Electrophysiologic procedures, including catheter ablation of AV nodal re-entrant tachycardia, septal accessory pathways, para-Hisian atrial tachycardia, or premature ventricular complexes, are also associated with risk of AV conduction system injury. In this article, we summarize the common causes for iatrogenic AV block, predictors for AV block, and general management considerations.
Topics: Humans; Atrioventricular Block; Heart Conduction System; Tachycardia, Atrioventricular Nodal Reentry; Transcatheter Aortic Valve Replacement; Iatrogenic Disease; Catheter Ablation
PubMed: 37321692
DOI: 10.1016/j.ccl.2023.03.009 -
Cardiac Electrophysiology Clinics Dec 2021Congenital complete heart block (CCHB) defines atrioventricular conduction abnormalities diagnosed in utero or within the first 27 days of life. Maternal autoimmune... (Review)
Review
Congenital complete heart block (CCHB) defines atrioventricular conduction abnormalities diagnosed in utero or within the first 27 days of life. Maternal autoimmune disease and congenital heart defects are most commonly responsible. Recent genetic discoveries have highlighted our understanding of the underlying mechanism. Hydroxychloroquine shows promise in preventing autoimmune CCHB. Patients may develop symptomatic bradycardia and cardiomyopathy. The presence of these and other specific findings warrants placement of a permanent pacemaker to relieve symptoms and prevent catastrophic events. The mechanisms, natural history, evaluation, and treatment of patients with or at risk for CCHB are reviewed.
Topics: Atrioventricular Block; Bradycardia; Heart Block; Heart Defects, Congenital; Humans; Pacemaker, Artificial
PubMed: 34689896
DOI: 10.1016/j.ccep.2021.07.006 -
Cardiology Clinics Aug 2023Delayed atrioventricular (AV) conduction most commonly occurs in the AV node, resulting from AH prolongation on an intracardiac electrocardiogram and PR prolongation on... (Review)
Review
Delayed atrioventricular (AV) conduction most commonly occurs in the AV node, resulting from AH prolongation on an intracardiac electrocardiogram and PR prolongation on a surface electrocardiogram. AV conduction may be blocked in a 2:1 manner, with a normal PR interval and wide QRS suggesting infranodal disease, whereas a prolonged PR interval and narrow QRS are more suggestive of AV nodal disease. Block within the His is suspected when there is 2:1 AV block with normal PR and QRS intervals. Complete heart block occurs when the atrial rhythm is totally independent of a junctional or lower escape rhythm.
Topics: Humans; Atrioventricular Block; Atrioventricular Node; Electrocardiography; Heart Rate
PubMed: 37321683
DOI: 10.1016/j.ccl.2023.03.007 -
Internal Medicine (Tokyo, Japan) Mar 2021
Topics: Atrioventricular Block; Electrocardiography; Heart Conduction System; Humans; Pacemaker, Artificial
PubMed: 33087679
DOI: 10.2169/internalmedicine.6150-20 -
JAMA Internal Medicine May 2021
Topics: Atrioventricular Block; Humans
PubMed: 33555309
DOI: 10.1001/jamainternmed.2020.8595 -
Cardiology Clinics Aug 2023Atrioventricular blocks may be caused by a variety of potentially reversible conditions, such as ischemic heart disease, electrolyte imbalances, medications, and... (Review)
Review
Atrioventricular blocks may be caused by a variety of potentially reversible conditions, such as ischemic heart disease, electrolyte imbalances, medications, and infectious diseases. Such causes must be always ruled out to avoid unnecessary pacemaker implantation. Patient management and reversibility rates depend on the underlying cause. Careful patient history taking, monitoring of vital signs, electrocardiogram, and arterial blood gas analysis are crucial elements of the diagnostic workflow during the acute phase. Atrioventricular block recurrence after the reversal of the underlying cause may pose an indication for pacemaker implantation, because reversible conditions may actually unmask a preexistent conduction disorder.
Topics: Humans; Atrioventricular Block; Pacemaker, Artificial; Electrocardiography; Myocardial Ischemia
PubMed: 37321691
DOI: 10.1016/j.ccl.2023.03.004