1/300. AV reentrant and idiopathic ventricular double tachycardias: complicated interactions between two tachycardias.An electrophysiological study was performed in a 61 year old man with Wolff- Parkinson-White (WPW) syndrome. At baseline, neither ventricular nor supraventricular tachycardias could be induced. During isoprenaline infusion, ventricular tachycardia originating from the right ventricular outflow tract (RVOT) with a cycle length of 280 ms was induced and subsequently atrioventricular reentrant tachycardia (AVRT) with a cycle length of 300 ms using an accessory pathway in the left free wall appeared. During these tachycardias, AVRT was entrained by ventricular tachycardia. The earliest ventricular activation site during the ventricular tachycardia was determined to be the RVOT site and a radiofrequency current at 30 W successfully ablated the ventricular tachycardia at this site. The left free wall accessory pathway was also successfully ablated during right ventricular pacing. The coexistence of WPW syndrome and cathecolamine sensitive ventricular tachycardia originating from the RVOT has rarely been reported. Furthermore, the tachycardias were triggered by previous tachycardias.- - - - - - - - - - ranking = 1keywords = accessory (Clic here for more details about this article) |
2/300. catheter ablation in a patient with a congenital giant right atrial diverticulum presented as wolff-parkinson-white syndrome.A young woman symptomatic for tachycardia showed right ventricular preexcitation on the surface ECG with a pattern during induced atrial fibrillation suggestive of multiple APs. Noninvasive imaging techniques performed prior to catheter ablation demonstrated the presence of a giant right atrial diverticulum confirmed by hemodynamic procedure. This structure functioned as an enormous accessory AP. We performed catheter ablation of this pathway using a special 4-mm multipolar catheter inside the diverticulum. This is the first case of such as anomaly being successfully treated with catheter ablation.- - - - - - - - - - ranking = 0.5keywords = accessory (Clic here for more details about this article) |
3/300. Antidromic reciprocating tachycardia in patients with paraseptal accessory pathways: importance of critical delay in the reentry circuit.Previous studies in patients with antidromic reciprocating tachycardia (ART) have observed a critical anatomic requirement (> 4 cm) between an antegrade bypass tract limb and a retrograde AV nodal limb. We report two patients with ART utilizing a paraseptal accessory pathway. In both cases, a critical degree of slow conduction within the circuit provides unusual electrophysiologic substrate to overcome the expected anatomical constraints.- - - - - - - - - - ranking = 2.5keywords = accessory (Clic here for more details about this article) |
4/300. ST segment elevation in the right precordial leads induced with class IC antiarrhythmic drugs: insight into the mechanism of brugada syndrome.We evaluated two patients without previous episodes of syncope who showed characteristic ECG changes similar to brugada syndrome following administration of Class IC drugs, flecainide and pilsicainide, but not following Class IA drugs. Patient 1 had frequent episodes of paroxysmal atrial fibrillation resistant to Class IA drugs. After treatment with flecainide, the ECG showed a marked ST elevation in leads V2 and V3, and the coved-type configuration of ST segment in lead V2. A signal-averaged ECG showed late potentials that became more prominent after flecainide. Pilsicainide, a Class IC drug, induced the same ST segment elevation as flecainide, but procainamide did not. Patient 2 also had frequent episodes of paroxysmal atrial fibrillation. Pilsicainide changed atrial fibrillation to atrial flutter with 2:1 ventricular response, and the ECG showed right bundle branch block and a marked coved-type ST elevation in leads V1 and V2. After termination of atrial flutter, ST segment elevation in leads V1 and V2 continued. In this patient, procainamide and quinidine did not induce this type of ECG change. In conclusion, strong Na channel blocking drugs induce ST segment elevation similar to brugada syndrome even in patients without any history of syncope or ventricular fibrillation.- - - - - - - - - - ranking = 0.049371180298069keywords = bundle (Clic here for more details about this article) |
5/300. Right coronary artery occlusion as a complication of accessory pathway ablation in a 12-year-old treated with stenting.We describe a complication of radiofrequency ablation of a posteroseptal pathway that resulted in acute occlusion of a distal right coronary artery in a pediatric patient. The complication was treated with coronary stenting after unsuccessful angioplasty.- - - - - - - - - - ranking = 2keywords = accessory (Clic here for more details about this article) |
6/300. Radiofrequency ablation of a concealed nodoventricular Mahaim fiber guided by a discrete potential.INTRODUCTION: We present the case of a 17-year-old woman who underwent an electrophysiological study and radiofrequency (RF) ablation of supraventricular tachycardia refractory to medical treatment. Two right-sided, concealed, nondecremental atrioventricular accessory pathways (AV-APs) involved in orthodromic circus movement tachycardias were identified. After RF ablation of both AV-APs, evidence of bidirectional dual AV nodal conduction was demonstrated and regular narrow complex tachycardia was induced. methods AND RESULTS: During the tachycardia, retrograde slow and fast AV nodal pathway conduction with second-degree ventriculoatrial (VA) block and VA dissociation were observed. During the tachycardia with second-degree VA block, ventricular extrastimuli elicited during His-bundle refractoriness advanced the next His potential or terminated the tachycardia. Mapping the right atrial mid-septal region, a distinct high-frequency activation P potential was recorded in a discrete area, two thirds of the way from the His bundle toward the os of the coronary sinus. Detailed electrophysiologic testing with the recordable P potential demonstrated that the tachycardia utilized a concealed nodoventricular AP arising from the proximal slow AV nodal pathway. CONCLUSION: The tachycardia with slow 1:1 VA conduction could be reset by ventricular extrastimuli elicited during His-bundle refractoriness advancing the subsequent activation P potential and atrial activation. RF ablation guided by recording of the activation P potential resulted in elimination of both the slow AV nodal pathway and the nodoventricular connection with preservation of the normal AV conduction system.- - - - - - - - - - ranking = 0.64811354089421keywords = accessory, bundle (Clic here for more details about this article) |
7/300. Electrophysiologic characteristics of accessory atrioventricular connections in an inherited form of wolff-parkinson-white syndrome.INTRODUCTION: A familial form of wolff-parkinson-white syndrome (WPW) occurs in association with hypertrophic cardiomyopathy and intraventricular conduction abnormalities. This syndrome, demonstrating autosomal dominant inheritance and segregating with a high degree of penetrance but variable expressivity, has been genetically linked to chromosome 7q3. The purpose of this study is to detail the electrophysiologic characteristics of accessory atrioventricular connections (AC) in four members of a kindred with this syndrome. methods AND RESULTS: We clinically evaluated 32 members of a single kindred and identified 20 individuals with ventricular preexcitation, abnormal intraventricular conduction including complete AV block and/or ventricular hypertrophy. genetic linkage analysis mapped the disease gene in this kindred to the chromosome 7q3 locus (maximum logarithm of the odds score = 6.88, theta = 0); recombination events in affected individuals reduced the genetic interval from 7 centimorgans (cM) to 5 cM. Electrophysiologic study of four individuals with preexcitation, identified seven AC (1 right sided, 3 septal, and 3 left sided). All four individuals had inducible orthodromic tachycardia; while three had multiple AC. Bidirectional conduction was demonstrated in 6 of 7 AC. Successful ablation was accomplished in 5 of 7 AC. CONCLUSION: The electrophysiologic characteristics and location of AC in family members having this complex cardiac phenotype are similar to those seen in individuals with isolated WPW. Identification of WPW in more than one family member should prompt clinical evaluation of relatives for additional findings of ventricular hypertrophy or conduction abnormalities.- - - - - - - - - - ranking = 2.5keywords = accessory (Clic here for more details about this article) |
8/300. Coexisting preexcitation syndrome and intermittent heart block presenting as neonatal seizures.An infant presented with neonatal syncope and seizures. An ECG showed a preexcitation pattern, most compatible with Wolff-Parkinson-White (WPW) syndrome. Rhythm monitoring during an event demonstrated prolonged periods of complete AV block with no ventricular escape mechanism. We postulated that ventricular asystole was initiated by mechanical or autonomic influences on the accessory pathway and sustained by electrophysiologic interactions between the accessory pathway and the junctional escape focus. This is the first case report of a newborn having coexisting congenital AV block and WPW syndrome.- - - - - - - - - - ranking = 1keywords = accessory (Clic here for more details about this article) |
9/300. Ebstein's anomaly of the tricuspid valve associated with congenital deafmutism.Ebstein's anomaly is the most common congenital abnormality of the tricuspid valve and accounts for about 0.5% of cases of the congenital heart diseases. It has occasionally been associated with other syndromes but not with the congenital deafmutism. The first case of Ebstein's anomaly associated with the congenital deafmutism is reported. The patient remained asymptomatic until the age of 35 years and presented with palpitations and dizzy spells. This patient also manifested mitral valve prolapse and wolff-parkinson-white syndrome with right-sided accessory conduction pathway.- - - - - - - - - - ranking = 0.5keywords = accessory (Clic here for more details about this article) |
10/300. electrocardiography in the patient with the wolff-parkinson-white syndrome: diagnostic and initial therapeutic issues.The wolff-parkinson-white syndrome (WPW), estimated to occur in approximately 0.1% to 3% of the general population, is a form of ventricular preexcitation involving an accessory conduction pathway. The definition of WPW relies on the following electrocardiographic features: (1) a PR interval less than 0.12 seconds (2) with a slurring of the initial segment of the QRS complex, known as a delta wave, (3) a QRS complex widening with a total duration greater than 0.12 seconds, and (4) secondary repolarization changes reflected in ST segment-T wave changes that are generally directed opposite (discordant) to the major delta wave and QRS complex changes. The accessory pathway bypasses the atrioventricular (AV) node, creating a direct electrical connection between the atria and ventricles. The majority of patients with preexcitation syndromes remain asymptomatic throughout their lives. When symptoms do occur they are usually secondary to tachyarrhythmias; the importance of recognizing this syndrome is that these patients may be at risk to develop a variety of supraventricular tachyarrhythmias which cause disabling symptoms and, in the extreme, sudden cardiac death. The tachyarrhythmias encountered in the WPW patient include paroxysmal supraventricular tachycardia (both the narrow QRS and wide QRS complex varieties), atrial fibrillation, atrial flutter, and ventricular fibrillation. Diagnostic and urgent, initial therapeutic issues based on initial electrocardiographic information are presented via 5 illustrative cases.- - - - - - - - - - ranking = 1keywords = accessory (Clic here for more details about this article) |
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