Objective: To review the clinical data of 7 patients with Danon disease and analyze their clinical characteristics. Methods: The medical records of 7 patients with Danon disease, who were hospitalized in Peking Union Medical College Hospital of Chinese Academy of Medical Sciences from April 2008 to July 2021, were reviewed and summarized, of which 6 cases were diagnosed as Danon disease by lysosomal-associated membrane protein-2 (LAMP-2) gene mutation detection and 1 case was diagnosed by clinicopathological features. Clinical manifestations, biochemical indexes, electrocardiogram, echocardiography, skeletal muscle and myocardial biopsy and gene detection results were analyzed, and patients received clinical follow-up after discharge. Results: Six patients were male and average age was (15.4±3.5) years and the average follow-up time was (27.7±17.0) months. The main clinical manifestations were myocardial hypertrophy (6/7), decreased myodynamia (2/7) and poor academic performance (3/7). Electrocardiogram features included pre-excitation syndrome (6/7) and left ventricular hypertrophy (7/7). Echocardiography examination evidenced myocardial hypertrophy (6/7), and left ventricular dilatation and systolic dysfunction during the disease course (1/7). The results of skeletal muscle biopsy in 6 patients were consistent with autophagy vacuolar myopathy. Subendocardial myocardial biopsy was performed in 3 patients, and a large amount of glycogen deposition with autophagosome formation was found in cardiomyocytes. LAMP-2 gene was detected in 6 patients, and missense mutations were found in all these patients. During the follow-up period, implantable cardioverter defibrillator implantation was performed in 1 patient because of high atrioventricular block 4 years after diagnosis, and there was no death or hospitalization for cardiovascular events in the other patients. Conclusion: The main clinical manifestations of Danon disease are cardiomyopathy, myopathy and mental retardation. Pre-excitation syndrome is a common electrocardiographic manifestation. Autophagy vacuoles can be seen in skeletal muscle and myocardial pathological biopsies. LAMP-2 gene mutation analysis is helpful in the diagnose of this disease.
Adolescent ; Child ; Female ; Humans ; Male ; Cardiomyopathies/etiology* ; Glycogen Storage Disease Type IIb/complications* ; Hypertrophy, Left Ventricular/etiology* ; Lysosomal-Associated Membrane Protein 2/genetics* ; Pre-Excitation Syndromes/genetics*

Wide QRS complex tachycardia with a left bundle branch block pattern can be caused by supraventricular tachycardia with aberrant conduction, preexcitation syndrome mediated through a right-sided accessory pathway, and/or ventricular tachycardia. The use of atrial pacing maneuvers can be beneficial for unmasking minimal preexcitation to differentiate between these conditions. Here, we report a case of successful radiofrequency catheter ablation of a Mahaim fiber in a patient with wide QRS complex tachycardia.
Bundle-Branch Block ; Catheter Ablation ; Humans ; Pre-Excitation Syndromes* ; Tachycardia ; Tachycardia, Supraventricular ; Tachycardia, Ventricular

Among patients with Wolff-Parkinson-White syndrome, atrioventricular reciprocating tachycardia (AVRT) and atrioventricular nodal reentrant tachycardia (AVNRT) can coexist in a single patient. Direct transition of both tachycardias is rare; however, it can occur after premature atrial or ventricular activity if the cycle lengths of the two tachycardias are similar. Furthermore, persistent atrial activation by an accessory pathway (AP) located outside of the AV node during ongoing AVNRT is also rare. This article describes a case of uncommon atrial activation by an AP during AVNRT and gradual transition of the two supraventricular tachycardias without any preceding atrial or ventricular activity in a patient with preexcitation syndrome.
Atrioventricular Node ; Humans ; Pre-Excitation Syndromes ; Tachycardia* ; Tachycardia, Atrioventricular Nodal Reentry ; Tachycardia, Paroxysmal ; Tachycardia, Reciprocating ; Tachycardia, Supraventricular ; Wolff-Parkinson-White Syndrome*

Pre-excitation-syndrome has not been reported as a phenotypic feature of facio-scapulo-humeral muscular dystrophy (FSH-MD). In a 39-year-old male with FSH-MD due to a reduced tandem repeat size in the D4Z4-locus on chromosome 4q35, cardiac involvement, manifesting as an incomplete right bundle-branch-block, tall T-waves in V 3-5, ST-elevation in V 2-4, and mild thickening of the left ventricular myocardium, was first recognised 10 years earlier. Follow-up at age 39 years revealed mild myocardial thickening, two intra-ventricular aberrant bands, and, surprisingly, intermittent pre-excitation on a routine electrocardiography. Cardiac involvement in FSH-MD may manifest as hypertrophic cardiomyopathy or various arrhythmias, of which one may be pre-excitation-syndrome.
Adult ; Arrhythmias, Cardiac ; Cardiomyopathies ; Cardiomyopathy, Hypertrophic ; Electrocardiography ; Follow-Up Studies ; Heart ; Humans ; Male ; Muscular Dystrophies* ; Myocardium ; Pre-Excitation Syndromes ; Tandem Repeat Sequences

Adult ; Child, Preschool ; Heart Ventricles ; pathology ; Humans ; Male ; Myocardium ; pathology ; Pre-Excitation Syndromes ; etiology ; pathology

OBJECTIVEThe gamma(2) subunit of AMP-activated protein kinase (PRKAG2) located in chromosome 7 plays an important role in regulating metabolic pathways, and patients with PRKAG2 mutations are associated with familial ventricular pre-excitation, hypertrophic cardiomyopathy and AV block. We observed the difference on the phenotypes in a large family with same PRKAG2 mutation.

METHODDirect DNA sequence was performed to screen the exons and exon-intron boundaries of PRKAG2 gene in a large family with 13 affected persons detected by electrocardiography (ECG).

RESULTSSinus bradycardia, short PR interval, right bundle bunch block (RBBB), complete AV block, atrial flutter, atrial fibrillation and sudden cardiac death were identified in this family. Hypertrophic cardiomyopathy was found in one family member. Genetic analysis revealed a missense mutation (Arg302Glu) in all affected family members. This mutation was previous described in patients with Wolff-Parkinson-White (WPW) syndrome and hypertrophic cardiomyopathy.

CONCLUSIONSBesides WPW syndrome and hypertrophic cardiomyopathy, PRKAG2 mutations are responsible also for a diverse phenotypes. PRKAG2 gene mutation should be suspected with familial occurrence of RBBB, sinus bradycardia, and short PR interval.

AMP-Activated Protein Kinases ; genetics ; Arrhythmias, Cardiac ; genetics ; Brazil ; Female ; Genotype ; Humans ; Male ; Mutation ; Pedigree ; Phenotype ; Pre-Excitation Syndromes ; etiology

We report a case in which WPW (Wolff-Parkinson-White)-type preexcitation syndrome arose unexpectedly immediately after induction of general anesthesia on a 25-yr-old man who had another rare cardiac arrhythmia, parasystole. His preoperative ECG showed ventricular bigeminy and a delta wave was observed after induction of anesthesia with fentanyl, midazolam and propofol. Anesthesia was maintained with propofol, fentanyl and nitrous oxide. The intraoperative ECG showed varying and temporary responsiveness to drugs such as atropine, lidocaine and ephedrine. After we started to infuse the dobutamine, the delta wave, ventricular bigeminy disappeared on the intraoperative ECG. We should consider the influence of anesthesia-related agents on arrhythmia, and aim to prevent and manage tachyarrhythmias caused by this syndrome.
Anesthesia ; Anesthesia, General* ; Arrhythmias, Cardiac ; Atropine ; Dobutamine ; Electrocardiography ; Ephedrine ; Fentanyl ; Humans ; Lidocaine ; Midazolam ; Nitrous Oxide ; Parasystole* ; Pre-Excitation Syndromes* ; Propofol ; Tachycardia ; Wolff-Parkinson-White Syndrome

PURPOSE: This study was conducted to establish the prevalence and clinical features of WPW- type ventricular preexcitation syndrome in children. METHODS: Eighteen patients were discovered by the mass heart disease screening using ECG on 47,691 elementary school children in Kwangju from September 1992 to December 1994 (group 1), and 14 patients were diagnosed at the Department of Pediatrics, Chonnam University Hospital from 1991 to August 1995 (group 2). We retrospectively reviewed patients' medical records. RESULTS: The prevalence rate was 4 per 10,000 elementary school children and there was no sexual difference. All patients in group 1 were asymptomatic, but 5 patients in group 2 had symptoms related to tachyarrhythmias. Three patients with WPW syndrome and paroxysmal supraventricular tachycardia who underwent radiofrequency catheter ablation have been well without recurrence of tachyarrhythmias during the follow-up period of 29-45 months. Two cases in group 2 had structural cardiac lesion (ventricular septal defect in 1, mitral valve prolapse in 1). CONCLUSION: The prevalence rate of Koreans was lower than that of foreigners. The radiofrequency catheter ablation seemed to be relatively safe and effective for the treatment of atrioventricular reentrant tachycardia utilizing accessory pathway in childhood patients if this procedure is technically feasible. However, continuous longitudinal studies are needed to evaluate the long-term natural history and prognosis of the WPW-type ventricular preexcitation syndrome.
Catheter Ablation ; Child* ; Electrocardiography ; Emigrants and Immigrants ; Follow-Up Studies ; Gwangju ; Heart Diseases ; Humans ; Jeollanam-do ; Longitudinal Studies ; Mass Screening ; Medical Records ; Mitral Valve Prolapse ; Natural History ; Pediatrics ; Pre-Excitation Syndromes* ; Prevalence* ; Prognosis ; Recurrence ; Retrospective Studies ; Tachycardia ; Tachycardia, Supraventricular ; Wolff-Parkinson-White Syndrome

The Wolff-Parkinson-White syndrome (WPW syndrome) and its variants are called the preexcitation syndrome. Anesthetic management of the patient with WPW syndrome requires the minimizing or avoidance of tachyarrythmias. Various anesthetic plans are employed for this purpose. For example, N2O, oxygen and narcotic technique, neuroleptanalgesia, deep inhalation anesthesia are included in this category. We have recently anesthetized a patient with preexcitation syndrome, performing continuous epidural anesthesia with 2% lidocaine and single bolus injection of Innovar followed by general endotracheal inhalation anesthesia with enflurane, and our experience suggested that this anesthetic method might be useful for the patients with WPW syndrome and below-lower abdomen operation.
Abdomen ; Anesthesia, Epidural ; Anesthesia, Inhalation* ; Enflurane ; Humans ; Inhalation* ; Lidocaine ; Neuroleptanalgesia ; Oxygen ; Pre-Excitation Syndromes ; Tachycardia ; Wolff-Parkinson-White Syndrome*

In order to determine the electrophysiologic properties of aberrant ventricular conduction we analyzed the electrophysiologic studies done for various reasons in SNUH(1983.3 -1987.8). All patients did not have underlying heart disease and were in sinus rhythm with normal PR intervals & no intraventricular conduction delay at the time of study. The patients of preexcitation syndrome were excluded. Only aberrant ventricular conduction induced by premature atrial stimulation at the high right atrium or(HRA) during sinus rhythm or HRA pacing was analyzed. 1) Aberrant ventricular conuction was induced by premature atrial extrastimulation in 34 subjects of 156 cases reviewed(21.8%). The patients were 16 to 70 years old(sixteen males and eighteen females). 2) The longest atrial coupling(A1S2) interval resulting in aberrant ventricular conduction approximated 45%(600-280) of the basic cycle length(450-1550 msec). 3) As a prerequisite for aberrant ventricular conduction, the functional refractory period(FRP) of the AV node should be less than the relative refractory period(RRP) of the His Purkinje System and the most important determinant of aberrant ventricular conduction by atrial extreastimulation was resultant H1H2 interval, which should be between RRP and effective refractory period(ERP) of HPS. 4) There was good linear correlation between the basic cycle length(BCL) and RRP of the HPS(RRP=0.247xBCL+247.048, r=0.885, p-value<0.001). 5) 155 different configurations of aberrant ventricular conduction were recorded during atrial extrastimulation till atrial ERP. The pattern frequencies were as follows : left anterior hemiblock, 6(3.9%) ; right bundle brach block, 92(59.4%) ; left bundle branch block, 28(18.0%) ; left anterior hemiblock combined with right bundle branch block, 14(9.0%) ; left posterior hemiblock combined with right bundle branch block, 9(5.8%) ; unclassified intraventricular conduction disturbances, 6(3.9%). 6) As the atrial coupling intervals were further shortened, aberrant conduction persisted up to the point of atrial ERP at 19/41 BCL's(46.3%). Other patterns of atrioventricular conduction were as follows : atrio-His block, 7(17.1%) ; His-ventricular block, 6(14.6%) ; normal conduction due to prolonged A2H2, 9(22.0%). But there was no statistical significance between the pattern of A-V conduction and the longest S2H2 & H2V2 intervals during VAB (p-value=0.235>0.050). In conclusion, atrial extrastimulation which is routinely done during clinical EPS is an effective method to induce aberrant ventricular conduction and to study the electrophysiologic characteristics of atrioventricular conduction. Further study with recording of bundle branch electrogram, after infusion of cardioactive drugs and pacing of HRA at fixed rate should be done to determine the electrophysiologic properties of VAB more completely.
Atrioventricular Node ; Bundle-Branch Block ; Heart Atria ; Heart Diseases ; Humans ; Male ; Pre-Excitation Syndromes