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European Heart Journal. Case Reports Jun 2023Anti-mitochondrial antibody (AMA)-associated myopathy is known to be concomitant with primary biliary cirrhosis and to cause both skeletal muscle disorders and...
BACKGROUND
Anti-mitochondrial antibody (AMA)-associated myopathy is known to be concomitant with primary biliary cirrhosis and to cause both skeletal muscle disorders and arrhythmias, myocardium disorders, and respiratory muscle disorders. We report a case of AMA-associated myopathy in which the bradycardia-related symptoms preceded the skeletal muscle symptoms.
CASE SUMMARY
A 59-year-old woman visited the emergency room in our hospital following a syncopal event. The patient was bradycardiac (45 b.p.m.) with a junctional rhythm resulting from sick sinus syndrome (SSS) and was suffering from heart failure. Blood tests revealed elevated creatine kinase (CK) and hepatic enzymes. She underwent permanent pacemaker implantation. However, it proved difficult to detect the electrical potential in the right atrium. Although successful atrial pacing was achieved at the lower right atrial septum, the atrial threshold was markedly high and she depended on ventricular pacing. One year later, neurological examination and muscle biopsy confirmed the diagnosis of AMA-associated myopathy. Following this diagnosis, steroid pulse therapy was initiated. Steroid administration relieved her symptoms and lowered the CK levels but the atrial standstill persisted. The patient takes low-dose prednisolone and has had an uneventful course for 3 years.
DISCUSSION
To the best of our knowledge, this is the first case of AMA-associated myopathy diagnosed by the first symptom related to bradycardia due to SSS. Patients with AMA-associated myopathy can experience a variety of cardiac symptoms, including arrhythmias, and initially complain of cardiac symptoms without symptoms of skeletal myopathy. This disease should be considered when diagnosing patients with arrhythmia and elevated CK.
PubMed: 37323533
DOI: 10.1093/ehjcr/ytac158 -
Journal of Clinical Medicine Feb 2021Cardiac involvement in patients with muscular dystrophy associated with Lamin A/C mutations () is characterized by atrioventricular conduction abnormalities and...
INTRODUCTION
Cardiac involvement in patients with muscular dystrophy associated with Lamin A/C mutations () is characterized by atrioventricular conduction abnormalities and life-threatening cardiac arrhythmias. Little is known about cardiac involvement in patients with emerin mutation (). The aim of our study was to describe and compare the prevalence and time distribution of cardiac arrhythmias at extended follow-up.
PATIENTS AND METHODS
45 consecutive patients affected by muscular dystrophy associated to laminopathy or emerinopathy were examined. All patients underwent clinical evaluation, 12-lead surface electrocardiogram (ECG), 24 h electrocardiographic monitoring, and cardiac implanted device interrogation.
RESULTS
At the end of 11 (5.0-16.6) years of follow-up, 89% of the patients showed cardiac arrhythmias. The most prevalent was atrial standstill (AS) (31%), followed by atrial fibrillation/flutter (AF/Afl) (29%) and ventricular tachycardia (22%). patients presented more frequently AF/AFl compared to (50% vs. 20%, ). Half of the patients presented with AS, whilst there was no occurrence of such in the ( = 0.001). Ventricular arrhythmias were found in 60% of patients with laminopathy compared to 3% in patients with emerinopathy ( < 0.001). The age of AVB occurrence was higher in the group (32.8 +/- 10.6 vs. 25.1 +/- 9.1, = 0.03).
CONCLUSIONS
Atrial arrhythmias are common findings in patients with muscular dystrophy associated with / mutations; however, they occurred earlier in patients. Ventricular arrhythmias were very common (60%) in and occurred definitely earlier compared to the group.
PubMed: 33673224
DOI: 10.3390/jcm10040732 -
CEN Case Reports Nov 2023Amyloid light chain (AL) amyloidosis is a rare hematologic disease that may involve multiple organs. Amongst the organs, cardiac involvement causes the greatest concern...
Cardiac and renal AL amyloidosis controlled by autologous stem cell transplantation for 17 years accompanying late onset atrial fibrillation and complete atrioventricular block.
Amyloid light chain (AL) amyloidosis is a rare hematologic disease that may involve multiple organs. Amongst the organs, cardiac involvement causes the greatest concern as its treatment is challenging. Diastolic dysfunction rapidly progresses to decompensated heart failure, pulseless electrical activity, and atrial standstill due to electro-mechanical dissociation resulting in death. High-dose melphalan plus autologous stem cell transplantation (HDM-ASCT) is the most radical treatment but its risk is very high and thus only less than 20% of patients can receive this therapy under criteria that can suppress treatment-related mortality. In substantial proportion of patients, levels of M protein remain elevated, and organ response cannot be achieved. Moreover, relapse may occur, making prediction of treatment response and judgement of disease eradication very difficult. Herein we report a case of AL amyloidosis who was treated with HDM-ASCT, resulting in preserved cardiac function and resolution of proteinuria for more than 17 years after HDM-ASCT ensuing atrial fibrillation and complete atrioventricular block required management by catheter ablation and pacemaker implantation 10 years and 12 years after transplantation, respectively.
Topics: Humans; Amyloidosis; Atrial Fibrillation; Atrioventricular Block; Hematopoietic Stem Cell Transplantation; Immunoglobulin Light-chain Amyloidosis; Melphalan; Neoplasm Recurrence, Local; Transplantation, Autologous
PubMed: 36795309
DOI: 10.1007/s13730-023-00777-8 -
Journal of the American Heart... Oct 2017There is increasing interest in the concept of atrial cardiomyopathy, but the underlying molecular and mechanistic determinants remain poorly defined. We identified a...
Dysfunction of Myosin Light-Chain 4 (MYL4) Leads to Heritable Atrial Cardiomyopathy With Electrical, Contractile, and Structural Components: Evidence From Genetically-Engineered Rats.
BACKGROUND
There is increasing interest in the concept of atrial cardiomyopathy, but the underlying molecular and mechanistic determinants remain poorly defined. We identified a family with heritable atrial cardiomyopathy manifesting as progressive atrial-selective electromechanical dysfunction, tachyarrhythmias, and bradyarrhythmias requiring pacemaker implantation. Myosin light-chain 4 (), encoding the atrial-selective essential myosin light chain, was identified as a candidate gene. We used genetically modified rat models to investigate the role of in atrial cardiomyopathy.
METHODS AND RESULTS
Exome sequencing and systematic bioinformatic analyses identified a rare missense variant of (c.31G>A []) in a large multiplex atrial cardiomyopathy family pedigree. The mutation cosegregated with atrial standstill (selected as the principal presenting trait) with a logarithm of the odds score of 5.3. The phenotype of rats with mutation knock-in confirmed the causative role of the mutation. knockout rats showed a similar atrial cardiomyopathy phenotype, whereas rats with an adjacent 4-amino-acid deletion showed no phenotype. Both knock-in rats and knockout rats showed progressive atrial electrophysiological, contractile, and fibrotic abnormalities, similar to affected patients. Biochemical analyses of mutation rats showed activation of proapoptotic and profibrotic signaling, along with increased atrial-cardiomyocyte terminal deoxynucleotidyl transferase dUTP nick end labeling staining, suggesting enhanced apoptotic cell death, findings that were mimicked by in vitro adenoviral transfer of the mutant gene to neonatal-rat cardiomyocytes.
CONCLUSIONS
Loss-of-function gene variants cause progressive atrial cardiomyopathy in humans and rats. Our findings identify as a key gene required for atrial contractile, electrical and structural integrity. These results improve our understanding of the molecular basis of atrial cardiomyopathy and introduce new models for further mechanistic analysis.
Topics: Action Potentials; Adult; Animals; Apoptosis; Arrhythmias, Cardiac; Atrial Remodeling; Cardiomyopathies; Disease Models, Animal; Female; Fibrosis; Genetic Predisposition to Disease; Heart Atria; Heart Conduction System; Heart Rate; Heredity; Humans; Male; Mutation, Missense; Myocardial Contraction; Myocytes, Cardiac; Myosin Light Chains; Phenotype; Rats, Transgenic; Signal Transduction; Young Adult
PubMed: 29080865
DOI: 10.1161/JAHA.117.007030 -
JFMS Open Reports 2022In this report, we provide detailed clinical, laboratory, electrocardiographic and echocardiographic descriptions of two -positive cats diagnosed with transient...
CASE SERIES SUMMARY
In this report, we provide detailed clinical, laboratory, electrocardiographic and echocardiographic descriptions of two -positive cats diagnosed with transient myocardial thickening (TMT) and acute myocardial injury (MI). In both cases, aetiological diagnosis was based on the antibody screening test (all cats had IgM titres ⩾1:64) and MI was demonstrated by a concomitant severe increase of the serum concentration of cardiac troponin I (5.1-23.6 ng/ml; upper hospital limit <0.2 ng/ml). In both cats, TMT and MI were aggravated by left atrial dilation and dysfunction, as well as congestive heart failure. In one cat, atrial standstill was also documented, while the other cat showed an intracardiac thrombus. Both cats underwent an extensive diagnostic work-up aimed at excluding additional comorbidities that could contribute to able to contribute to TMT and MI, and received appropriate antiprotozoal (ie, clindamycin) and cardiovascular therapy (eg, furosemide, pimobendan and clopidogrel). This was followed by a simultaneous decline in serology titres, normalisation of troponin level and the resolution of clinical, electrocardiographic, radiographic and echocardiographic abnormalities. In the light of these results, therapies were interrupted and subsequent controls ruled out any disease relapse.
RELEVANCE AND NOVEL INFORMATION
Although represents an often-cited cause of myocarditis in feline medicine, the existing literature on the demonstration of -associated cardiac compromise in cats is extremely limited. Accordingly, this report provides a useful contribution to pertinent scientific literature since it describes TMT and acute MI in two -positive cats.
PubMed: 36339325
DOI: 10.1177/20551169221131266 -
British Heart Journal Jun 1985Persistent atrial standstill occurred in a father and his youngest son with familial Ebstein's anomaly. In both cases routine electrocardiograms showed no atrial...
Persistent atrial standstill occurred in a father and his youngest son with familial Ebstein's anomaly. In both cases routine electrocardiograms showed no atrial electrical activity and cross sectional echocardiograms showed inferior displacement of the septal tricuspid leaflet and tethering of the tricuspid leaflets to the right ventricle. The father had a cerebral embolism and died of a myocardial infarction. Necropsy showed attachment of the septal tricuspid leaflet below the membranous septum. On serial histological examination fibrofatty infiltration of the right atrial wall, the atrioventricular node, and the inferior part of the His bundle up to the bifurcation was present. The son had haemodynamic and electrophysiological findings consistent with mild Ebstein's anomaly and persistent atrial standstill, for which permanent cardiac pacing was necessary. The persistent atrial standstill with slow escape rhythm was most probably a consequence of the abnormalities in both the atrial wall and the His bundle which, together with the abnormal attachment of the tricuspid valve, may be features of the same congenital cardiac anomaly.
Topics: Adult; Arrhythmias, Cardiac; Atrioventricular Node; Bundle of His; Ebstein Anomaly; Electrocardiography; Heart Atria; Humans; Male
PubMed: 4005080
DOI: 10.1136/hrt.53.6.594 -
Internal Medicine (Tokyo, Japan) 2017Objective Supraventricular arrhythmias are commonly detected in patients with anti-mitochondrial antibody M2 (AMA-M2)-associated myopathy. However, the prevalence of...
Objective Supraventricular arrhythmias are commonly detected in patients with anti-mitochondrial antibody M2 (AMA-M2)-associated myopathy. However, the prevalence of supraventricular arrhythmias in unselected AMA-M2-positive patients and the impact of AMA-M2 on supraventricular arrhythmias have yet to be fully investigated. Methods We analyzed 384 patients (116 men; age, 60 [48-69] years), who underwent AMA-M2 testing following the detection of elevated hepatobiliary enzymes. Supraventricular arrhythmias involving atrial fibrillation, atrial flutter, atrial tachycardia, sick sinus syndrome, and atrial standstill were confirmed by a 12-lead electrocardiogram, 24-hour ambulatory monitoring, and physician-assigned diagnoses within the three years before and two years after the AMA-M2 test. Results Seventy-seven (20%) patients were positive for AMA-M2. The prevalence of supraventricular arrhythmias among AMA-M2-positive patients was higher than that among AMA-M2-negative patients (14% vs. 6%, p=0.008). A univariate analysis showed that supraventricular arrhythmias were associated with AMA-M2 positivity, aging, congestive heart failure, and the CHADS score. The multivariate analysis determined that AMA-M2 positivity was an independent risk factor for supraventricular arrhythmias (odds ratio 3.52, p=0.011). Among the AMA-M2-positive patients, the AMA-M2 titer did not differ to a statistically significant extent, regardless of the presence or absence of supraventricular arrhythmias. Multiple supraventricular arrhythmias with extremely low atrial deflections was a characteristic finding in AMA-M2-positive patients with supraventricular arrhythmias. Conclusion AMA-M2 enhances the risk of supraventricular arrhythmias, indicating the possible involvement of the atrial myocardium and the formation of an arrhythmogenic substrate. The results highlight the need for clinical attention to supraventricular arrhythmias in AMA-M2-positive patients.
Topics: Aged; Antibodies; Atrial Fibrillation; Atrial Flutter; Electrocardiography; Enzymes; Humans; Male; Middle Aged; Mitochondria; Multivariate Analysis; Prevalence; Risk Factors; Tachycardia, Supraventricular
PubMed: 28717071
DOI: 10.2169/internalmedicine.56.8183 -
Korean Circulation Journal Sep 2015Isolated left ventricular noncompaction (LVNC) is a rare cardiomyopathy with morphologic characteristics of two distinct myocardial layers i.e., thin compacted...
Isolated left ventricular noncompaction (LVNC) is a rare cardiomyopathy with morphologic characteristics of two distinct myocardial layers i.e., thin compacted epicardial and thick noncompacted endocardial layers. The noncompacted myocardium consists of prominent ventricular trabeculae and deep intertrabecular recesses. It can lead to arrhythmias, heart failure or systemic embolisms. Electrocardiographic patterns of patients with LVNC are various and non-specific; however, the most common findings are intraventricular conduction delay, left ventricular hypertrophy, and repolarization abnormalities. We reported the first case, to the best of our knowledge, of a 29-year-old man who had recent cerebral infarction and incidental LVNC with spontaneous left atrial standstill.
PubMed: 26413113
DOI: 10.4070/kcj.2015.45.5.432 -
Frontiers in Cardiovascular Medicine 2023A pregnant patient had symptomatic atrial standstill and indications for pacing therapy with an expected high ventricular pacing ratio. With the consideration of...
A pregnant patient had symptomatic atrial standstill and indications for pacing therapy with an expected high ventricular pacing ratio. With the consideration of potential pacing-induced cardiomyopathy in the future we conducted zero-fluoro left bundle branch pacing (zLBBP) implantation for heart failure prevention. An ex vivo 3D cardiac model (Medtronic, USA) was used preoperatively to simulate the zLBBP implantation to improve procedure safety and efficiency. Intraoperatively, the simulation steps were followed, and a combination of electroanatomic navigation systems (EANS) and intracardiac echocariography (ICE) were used to ensure that the procedure was performed efficiently and safely.
PubMed: 38130689
DOI: 10.3389/fcvm.2023.1325442 -
HeartRhythm Case Reports Sep 2022
PubMed: 36147716
DOI: 10.1016/j.hrcr.2022.06.010