-
Journal of the American Society of... Jul 2020
Topics: Atrial Fibrillation; Cardiomyopathies; Cardiomyopathy, Hypertrophic; Genetic Diseases, Inborn; Heart Atria; Heart Block; Humans
PubMed: 32305175
DOI: 10.1016/j.echo.2020.02.011 -
Journal of the American Society of... Oct 2019
Topics: Adult; Atrial Fibrillation; Cardiomyopathies; Cardiomyopathy, Hypertrophic; Echocardiography, Doppler; Genetic Diseases, Inborn; Heart Atria; Heart Block; Humans; Male; Middle Aged
PubMed: 31351793
DOI: 10.1016/j.echo.2019.05.024 -
HeartRhythm Case Reports Jun 2019
PubMed: 31285994
DOI: 10.1016/j.hrcr.2019.03.008 -
SAGE Open Medical Case Reports 2019Atrial standstill is a rare arrhythmia defined by the absence of mechanical and electrical activity in the atria. Few cases of atrial standstill have been described in...
Atrial standstill is a rare arrhythmia defined by the absence of mechanical and electrical activity in the atria. Few cases of atrial standstill have been described in children, none of which have presented with cerebral infarction confirmed by imaging. We report a unique case of a 7-year-old girl presenting with expressive aphasia, central facial palsy and irregular pulse with cerebral infarction secondary to atrial standstill. This case illustrates that cardiogenic cerebral embolism in children can be caused by rare conditions like atrial standstill and should be considered in paediatric patients undergoing evaluation for stroke. There are no established treatment guidelines for atrial standstill. We recommend that treatment be directed towards any potential underlying cause. All patients with atrial standstill should receive long-term oral anticoagulation treatment and a permanent cardiac pacemaker implant to reduce the risk of further strokes or other cardiac events.
PubMed: 30783526
DOI: 10.1177/2050313X19827735 -
Journal of Veterinary Cardiology : the... Apr 2019Pacemaker implantation is considered as a standard procedure for treatment of symptomatic bradycardia in both dogs and cats. Advanced second-degree and third-degree... (Review)
Review
Pacemaker implantation is considered as a standard procedure for treatment of symptomatic bradycardia in both dogs and cats. Advanced second-degree and third-degree atrioventricular blocks, sick sinus syndrome, persistent atrial standstill, and vasovagal syncope are the most common rhythm disturbances that require pacing to either alleviate clinical signs or prolong survival. Most pacemakers are implanted transvenously, using endocardial leads, but rarely epicardial leads may be necessary. To decide whether a patient is a candidate for pacing, as well as which pacing modality should be used, the clinician must have a clear understanding of the etiology, the pathophysiology, and the natural history of the most common bradyarrhythmias, as well as what result can be achieved by pacing patients with different rhythm disturbances. The goal of this review was, therefore, to describe the indications for pacing by evaluating the available evidence in both human and veterinary medicine. We described the etiology of bradyarrhythmias, clinical signs and electrocardiographic abnormalities, and the choice of pacing modality, taking into account how different choices may have different physiological consequences to selected patients. It is expected that this review will assist veterinarians in recognizing arrhythmias that may require permanent pacing and the risk-benefit of each pacing modality and its impact on outcome.
Topics: Animals; Bradycardia; Cardiac Pacing, Artificial; Cat Diseases; Cats; Dog Diseases; Dogs; Pacemaker, Artificial
PubMed: 30709617
DOI: 10.1016/j.jvc.2018.12.003 -
International Heart Journal Jan 2019Emery-Dreifuss muscular dystrophy (EDMD) is a group of hereditary muscular dystrophy syndrome caused by deficiency of genes encoding nuclear envelope proteins. Patients... (Review)
Review
Emery-Dreifuss muscular dystrophy (EDMD) is a group of hereditary muscular dystrophy syndrome caused by deficiency of genes encoding nuclear envelope proteins. Patients having EDMD show the triad of muscle dystrophy, joint contracture, and cardiac disease. In almost all patients, cardiac involvement is prevalent and is the most severe aspect of EDMD. Cardiac disease is predominantly shown by conduction defects, atrial fibrillation/flutter, and atrial standstill. Sudden death and heart failure because of left ventricular dysfunction are important causes of mortality, particularly in those patients that have the LMNA mutation. Medical treatment of EDMD is limited to addressing symptoms and ambulation support; moreover, pacemaker implantation is necessary when there are severe conduction defects and bradycardia occurs. Note that automated defibrillation devices may be considered for those patients who have a high risk of sudden death, rate, or rhythm control. Also, anticoagulation should be initiated in those patients who have atrial fibrillation/flutter. Thus, for optimal management, a multidisciplinary approach is required.
Topics: Abnormalities, Multiple; Anticoagulants; Atrial Fibrillation; Cardiomyopathies; Cleft Palate; Contracture; Death, Sudden; Female; Genetic Diseases, Inborn; Heart Atria; Heart Block; Heart Diseases; Humans; Hydrocephalus; Interdisciplinary Communication; Limb Deformities, Congenital; Male; Muscular Dystrophies; Muscular Dystrophy, Emery-Dreifuss; Pacemaker, Artificial; Ventricular Dysfunction, Left
PubMed: 30518714
DOI: 10.1536/ihj.17-604 -
Journal of Cardiology Cases May 2018The long-term effects of enzyme replacement therapy (ERT) on cardiac function and the conduction system in Fabry disease are not clearly understood. We report a case of...
The long-term effects of enzyme replacement therapy (ERT) on cardiac function and the conduction system in Fabry disease are not clearly understood. We report a case of a 48-year-old man with non-classical Fabry disease treated with ERT for 11 years. He was diagnosed with Fabry disease at age 27 years based on the presence of decreased alpha-galactosidase A activity in the peripheral leukocytes and of the causal alpha-galactosidase A mutation (Val339Gln). Subsequently, peritoneal dialysis was initiated for renal failure at age 35 years. ERT was initiated at age 39 years to halt the progression of cardiac dysfunction. Electrical conduction disturbances progressed gradually to complete atrioventricular block with atrial standstill during 9 years of ERT despite the lack of progression of ventricular hypertrophy. Although he underwent permanent pacemaker implantation to prevent sudden cardiac death, the atrioventricular junctional rhythm remained, thereby lowering the ventricular pacing rate. Based on this case, we recognize that the effects of ERT are limited for inhibiting the progression of Fabry disease and especially for inhibiting arrhythmia and conduction disturbances. Early diagnosis of Fabry disease and early initiation of ERT might be the key to further improvements in this disease and its associated conditions. < We encountered a patient with Fabry disease treated with long-term enzyme replacement therapy (ERT) in whom conduction disturbances progressed without progression of left ventricular hypertrophy. This case suggests that ERT is limited for inhibiting the progression of Fabry disease and especially of arrhythmia and conduction disturbances. Early diagnosis of Fabry disease and initiation of ERT may be important for providing further improvements of this condition.>.
PubMed: 30279886
DOI: 10.1016/j.jccase.2018.01.004 -
Nucleus (Austin, Tex.) 2018Lamin A/C gene mutations can be associated with cardiac diseases, usually referred to as 'cardiolaminopathies' characterized by arrhythmic disorders and/or left... (Review)
Review
Lamin A/C gene mutations can be associated with cardiac diseases, usually referred to as 'cardiolaminopathies' characterized by arrhythmic disorders and/or left ventricular or biventricular dysfunction up to an overt picture of heart failure. The phenotypic cardiac manifestations of laminopathies are frequently mixed in complex clinical patterns and specifically may include bradyarrhythmias (sinus node disease or atrioventricular blocks), atrial arrhythmias (atrial fibrillation, atrial flutter, atrial standstill), ventricular tachyarrhythmias and heart failure of variable degrees of severity. Family history, physical examination, laboratory findings (specifically serum creatine phosphokinase values) and ECG findings are often important 'red flags' in diagnosing a 'cardiolaminopathy'. Sudden arrhythmic death, thromboembolic events or stroke and severe heart failure requiring heart transplantation are the most dramatic complications of the evolution of cardiolaminopathies and appropriate risk stratification is clinically needed combined with clinical follow-up. Treatment with cardiac electrical implantable devices is indicated in case of bradyarrhythmias (implant of a device with pacemaker functions), risk of life-threatening ventricular tachyarrhythmias (implant of an ICD) or in case of heart failure with wide QRS interval (implant of a device for cardiac resynchronization). New technologies introduced in the last 5 years can help physicians to reduce device-related complications, thanks to the extension of device longevity and availability of leadless pacemakers or defibrillators, to be implanted in appropriately selected patients. An improved knowledge of the complex pathophysiological pathways involved in cardiolaminopathies and in the determinants of their progression to more severe forms will help to improve clinical management and to better target pharmacological and non-pharmacological treatments.
Topics: Arrhythmias, Cardiac; Clinical Decision-Making; Heart Diseases; Humans; Lamin Type A; Musculoskeletal Diseases
PubMed: 30130999
DOI: 10.1080/19491034.2018.1506680 -
HeartRhythm Case Reports Aug 2018
PubMed: 30116708
DOI: 10.1016/j.hrcr.2018.04.015 -
Pacing and Clinical Electrophysiology :... May 2018Atrial standstill is an arrhythmogenic condition characterized by the absence of spontaneous electrical and mechanical atrial activity or in response to stimulation....
BACKGROUND
Atrial standstill is an arrhythmogenic condition characterized by the absence of spontaneous electrical and mechanical atrial activity or in response to stimulation. There are few reported familial cases which have been associated with SCN5A mutations cosegregating with GJA5 or RYR2; however, isolated SCN5A mutations are rare.
OBJECTIVE
The purpose of this study was to determine the clinical and biophysical consequence of a novel SCN5A mutation identified in a family with progressive atrial standstill and sudden death.
METHODS
The family of a sporadic case of congenital atrial standstill underwent genetic screening. Human Embryonic Kidney 293 cells were transfected with wild-type (WT) or mutant SCN5A cDNAs. Biophysical properties were studied using whole-cell using patch clamp methods.
RESULTS
A novel homozygous SCN5A mutation, p.V1340L, was identified in the proband and her sister. The proband had complete atrial standstill whereas the sister had partial atrial standstill. Heterozygous mutations were identified in the mother, father, and brother. All three had normal sinus rhythm and were asymptomatic. The mutant Nav1.5(V1340L) reduced Nav1.5 current density as well as showed a depolarizing shift in the voltage-dependent steady-state activation (WT: -35.3 ± 1.62 mV; V1340L: -22.4 ± 2.59 mV; P = 0.001).
CONCLUSIONS
A homozygous loss-of-function SCN5A mutation likely results in atrial standstill and sudden death due to suppression of initiation of action potential.
PubMed: 29781517
DOI: 10.1111/pace.13386