No abstract available.
Pre-Excitation Syndromes*

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

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

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

Since its initial description in 1930, the preexcitation or Wolff-Parkinson-White(W-P-W) syndrome is characterized by a special electrocardiographic pattern and various paroxysmal tachyarrhythmia, which was found to have reciprocating tachycardia frequently. The W-P-W syndrome develops when some part of a ventricle is activated earlier than normal conduction pathway, and described as one type of ventricular preexcitation syndromes by Durrer (1974). The diagnostic criteria of the W-P-W syndrome are 1) initial slurring (delta wave) of the QRS complex, 2) short P-R interval, 3) widened QRS complex and 4) secondary T wave change. The initial slurring of the QRS complex (delta wave) which is the most important finding of preexcitation syndrome results from a premature activation of a portion of the ventricle through an accessary pathway which bypasses the A-V node and bundle. These accessary conduction fiber includes Kent's bundle, Jame's fibers, Mahaim's fibers and its combination. Recent developments in the field of electrophysiology and surgical therapy became to support the concept of anomalous pathways and the possible determination of the re-entry circuit of paroxysmal tachycardia. Total 12 cases including 9 cases of classical W-P-W syndromes and 3 cases of L-G-L syndromes were followed with special interest of pre-excitation phenomenon and paroxysmal tachyarrhythmia at the National medical Center during the period of Jan. 1975 to Feb. 1979 and found to have paroxysmal tachyarrhythmia in 8 cases out of 12 cases. His bundle electrogram (HBE) and right atrial pacing were recoded in 2 cases of W-P-W type B to support the existance of an anomalous pathway. Treatment was instituted in accordance with recent advanced knowledge for the paroxysmal tachyarrhymia and pre-excitation and references were reviewed.
Atrioventricular Node ; Electrocardiography ; Electrophysiologic Techniques, Cardiac ; Electrophysiology ; Pre-Excitation Syndromes ; Tachycardia ; Tachycardia, Paroxysmal ; Tachycardia, Reciprocating ; 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*

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

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

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*