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Heart (British Cardiac Society) Jul 2013Vagally mediated atrioventricular (AV) block is defined as a paroxysmal AV block, localised within the AV node, associated with slowing of the sinus rate. All types of... (Review)
Review
Vagally mediated atrioventricular (AV) block is defined as a paroxysmal AV block, localised within the AV node, associated with slowing of the sinus rate. All types of second-degree AV block, including pseudo-Mobitz II block, and complete AV block, may be present. Most of the patients have normal AV conduction. Differential diagnosis with intrinsic AV block is based on the behaviour of the sinus rate. Vagally mediated AV block is benign; it can be recorded as an asymptomatic or symptomatic event (syncope/presyncope). Syncope due to this form of AV block should be diagnosed and managed as neurally mediated syncope. When this block is fortuitously recorded in asymptomatic patients, pacemaker implantation is not indicated.
Topics: Animals; Atrioventricular Block; Atrioventricular Node; Diagnosis, Differential; Electrocardiography; Electrophysiologic Techniques, Cardiac; Humans; Predictive Value of Tests; Prognosis; Syncope, Vasovagal; Vagus Nerve
PubMed: 23286970
DOI: 10.1136/heartjnl-2012-303220 -
Pacing and Clinical Electrophysiology :... Nov 2012Complete atrioventricular block is a relatively uncommon arrhythmia that is nonetheless increasingly seen in elderly people of developed countries, due to the increase... (Review)
Review
Complete atrioventricular block is a relatively uncommon arrhythmia that is nonetheless increasingly seen in elderly people of developed countries, due to the increase in life expectancy. Congenital and degenerative etiologies are the most commonly seen among young and old patients, respectively. However, scientific literature is surprisingly scarce regarding the etiology of complete atrioventricular block in the asymptomatic otherwise healthy young and middle-aged adult population. Coronary artery disease, autoimmune disorders such as systemic lupus erythematosus or rheumatoid arthritis, history of acute or chronic infectious or hypersensitivity myocarditis, infiltrative processes, hypothyroidism, congenital cardiopathies such as left ventricular noncompaction or Ebstein anomaly, lamin A/C mutations, and pathologic hypervagotony and idiopathic degenerative scleroatrophy of the atrioventricular junctional specialized tissue (Lenegre-Lev disease) are among the most frequent etiologies of complete atrioventricular block in young or middle-aged adults. To our knowledge, no comprehensive review on the specificities of the investigation warranted in this age group has ever been developed, nor have the implications of particular diagnoses on treatment modalities been appropriately addressed. We aim at reviewing the most frequent differential diagnoses of advanced atrioventricular block in otherwise healthy asymptomatic or mildly symptomatic young or middle-aged adults and their impact on therapeutic options. Additionally, we suggest a diagnostic algorithm that may be helpful in this group of patients.
Topics: Adult; Algorithms; Atrioventricular Block; Humans; Middle Aged; Young Adult
PubMed: 22897386
DOI: 10.1111/j.1540-8159.2012.03489.x -
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 -
Heart Rhythm Aug 2009Paroxysmal atrioventricular block (AVB) is a poorly defined clinical entity characterized by abrupt and unexpected change from 1:1 atrioventricular conduction to... (Review)
Review
Paroxysmal atrioventricular block (AVB) is a poorly defined clinical entity characterized by abrupt and unexpected change from 1:1 atrioventricular conduction to complete heart block, leading to syncope and potential sudden cardiac death. Although a dangerous condition because of unreliable escape mechanism, proper diagnosis of paroxysmal AVB is often missed and overlooked because of its unfamiliarity, unpredictability, and in some cases, no clear evidence of atrioventricular conduction disease during normal 1:1 conduction.
Topics: Adult; Aged; Aged, 80 and over; Atrioventricular Block; Death, Sudden, Cardiac; Female; Heart Conduction System; Humans; Male; Middle Aged; Prognosis; Risk Factors; Sinoatrial Node; Syncope
PubMed: 19632639
DOI: 10.1016/j.hrthm.2009.04.001 -
Internal Medicine (Tokyo, Japan) Mar 2021
Topics: Atrioventricular Block; Electrocardiography; Heart Conduction System; Humans; Pacemaker, Artificial
PubMed: 33087679
DOI: 10.2169/internalmedicine.6150-20 -
Heart, Lung & Circulation Dec 2023The widespread use of disparate definitions of atrioventricular block has created important diagnostic problems. Adherence to the correct definitions provides a logical... (Review)
Review
The widespread use of disparate definitions of atrioventricular block has created important diagnostic problems. Adherence to the correct definitions provides a logical and simple framework for clinical evaluation. This review focuses on the clinical importance of the definitions in the diagnosis of the various types of atrioventricular (AV) block and the associated diagnostic pitfalls.
Topics: Humans; Atrioventricular Block; Electrocardiography
PubMed: 37926640
DOI: 10.1016/j.hlc.2023.09.018 -
JAMA Internal Medicine May 2021
Topics: Atrioventricular Block; Humans
PubMed: 33555309
DOI: 10.1001/jamainternmed.2020.8595 -
JAMA Internal Medicine Aug 2021
Topics: Accidental Falls; Aged, 80 and over; Atrioventricular Block; Confusion; Diagnosis, Differential; Echocardiography; Electrocardiography; Electrophysiologic Techniques, Cardiac; Humans; Male; Pacemaker, Artificial; Prosthesis Implantation; Syncope
PubMed: 34125143
DOI: 10.1001/jamainternmed.2021.2526 -
British Journal of Pharmacology Mar 2022Ventricular cardiac arrhythmia is a life threating condition arising from abnormal functioning of many factors in concert. Animal models mirroring human... (Review)
Review
Ventricular cardiac arrhythmia is a life threating condition arising from abnormal functioning of many factors in concert. Animal models mirroring human electrophysiology are essential to predict and understand the rare pro- and anti-arrhythmic effects of drugs. This is very well accomplished by the canine chronic atrioventricular block (CAVB) model. Here we summarize canine models for cardiovascular research, and describe the development of the CAVB model from its beginning. Understanding of the structural, contractile and electrical remodelling processes following atrioventricular (AV) block provides insight in the many factors contributing to drug-induced arrhythmia. We also review all safety pharmacology studies, efficacy and mechanistic studies on anti-arrhythmic drugs in CAVB dogs. Finally, we compare pros and cons with other in vivo preclinical animal models. In view of the tremendous amount of data obtained over the last 100 years from the CAVB dog model, it can be considered as man's best friend in preclinical drug research. LINKED ARTICLES: This article is part of a themed issue on Preclinical Models for Cardiovascular disease research (BJP 75th Anniversary). To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v179.5/issuetoc.
Topics: Animals; Anti-Arrhythmia Agents; Arrhythmias, Cardiac; Atrioventricular Block; Dogs; Heart; Humans
PubMed: 33684961
DOI: 10.1111/bph.15436 -
The Journal of International Medical... Jan 2024Atrioventricular block (AVB) is a rare cardiac manifestation of hyperthyroidism (HTH). The scientific literature contains multiple reports of AVB in patients with HTH,... (Review)
Review
Atrioventricular block (AVB) is a rare cardiac manifestation of hyperthyroidism (HTH). The scientific literature contains multiple reports of AVB in patients with HTH, ranging from subclinical to overt HTH and even thyroid storm. However, much remains unknown about the true prevalence, clinical course, optimal management, and outcomes of AVB in patients with HTH. Such patients are possibly overtreated with pacemakers because of a lack of understanding that AVB might be secondary to the hyperthyroid state and thus reversible. This narrative review discusses the pathophysiology of AVB in patients with HTH in the context of the available evidence.
Topics: Humans; Atrioventricular Block; Hyperthyroidism; Patients; Heart
PubMed: 38206211
DOI: 10.1177/03000605231223040