Adenosine-sensitive decremental conduction over short non-decremental atrioventricular accessory pathways after radiofrequency ablation: case series.

Introduction: Decremental conduction in short anterograde atrioventricular accessory pathways (AV-APs) is rare.

Case Presentation: We report on two cases with radiofrequency (RF) ablation of anterograde fast non-decremental AV-AP conduction. In Case 1, electrophysiological testing revealed fast non-decremental conduction over an anterograde short right posteroseptal AV-AP.

A Retrograde Transaortic/Transmitral Approach for Radiofrequency Ablation of Adenosine-Sensitive Atrial Tachycardia Arising Near the Apex of Koch's Triangle: A Case Study Approach and Review of the Literature.

Atrial tachycardias (ATs) are relatively uncommon and their mechanisms include reentry or may be focal. The characteristics and radiofrequency (RF) ablation of adenosine-sensitive AT arising near the apex of Koch's triangle have been reported. We report a case of successful RF ablation of this tachycardia by using a retrograde transaortic/transmitral approach.

Nonfluoroscopic Imaging as Guidance for Radiofrequency Ablation of Atrioventricular Nodal Reentrant Tachycardia after Mustard Repair.

Most tachycardias in the pulmonary venous atrium are inaccessible by direct means and require either a retrograde approach or a transseptal approach for ablation. We present a case in which successful radiofrequency ablation of common atrioventricular nodal reentrant tachycardia was accomplished via a retrograde transaortic approach guided by nonfluoroscopic mapping with use of the NavX mapping system. The patient was a 49-year-old woman who at the age of 4 years had undergone Mustard repair for complete dextrotransposition of the great arteries.

Radiofrequency ablation of a left lateral atrioventricular accessory pathway in a 13-year-old boy with a criss-cross heart guided by nonfluoroscopic imaging.

We present the first description of successful radiofrequency (RF) ablation of a bidirectional atrioventricular accessory pathway (AP) guided by nonfluoroscopic mapping with use of three-dimensional magnetic resonance imaging integrated into the Nav-X system (MRI/Nav-X fusion) in a 13-year-old boy with remote surgical palliation for cyanotic criss-cross heart with atrioventricular discordance, double-outlet right ventricle, and a large ventricular septal defect. Due to complex anatomy, a unique finding was that the eliminated left lateral AP electrically connected the left atrium to the antero-superior morphologic right ventricle prior to ablation.

Decremental conduction properties in overt and concealed atrioventricular accessory pathways.

Aim: Most atrioventricular accessory pathways (AV-APs) exhibit Kent bundle physiology characterized by fast and non-decremental conduction properties. In contrast, atriofascicular APs, which are only capable of reaching slow levels of long antegrade decremental conduction, are uncommon. The aim of this study was to describe antegrade and/or retrograde AV-APs with unusual decremental properties.

Mahaim fibers: electrophysiologic characteristics and radiofrequency ablation.

Mahaim fibers that exhibit decremental atrioventricular (AV) node-like conduction properties are unusual, comprising < 3% of accessory pathways. They are involved in antidromic AV reciprocating (Mahaim) tachycardia with a left bundle branch block morphology. There is a frequent association of Mahaim pathways with Ebstein's anomaly, additional AV accessory pathways (Kent) and dual AV nodal pathway conduction.

Electrophysiologic characteristics and radiofrequency ablation of concealed nodofascicular and left anterograde atriofascicular pathways.

Introduction: True nodoventricular or nodofascicular pathways and left-sided anterograde decremental accessory pathways (APs) are considered rare findings.

Methods And Results: Two unusual patients with paroxysmal supraventricular tachycardia were referred for radiofrequency (RF) ablation. Both patients had evidence of dual AV nodal conduction.

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.

Inhibition of muscarinic K+ current in guinea-pig atrial myocytes by PD 81,723, an allosteric enhancer of adenosine binding to A1 receptors.

1. PD 81,723 has been shown to enhance binding of adenosine to A1 receptors by stabilizing G protein-receptor coupling ('allosteric enhancement'). Evidence has been provided that in the perfused hearts and isolated atria PD 81,723 causes a sensitization to adenosine via this mechanism.

Atrial double potentials associated with a left-sided accessory pathway having a single ventricular and two remote atrial insertions.

This paper reports the case of a 63-year-old female patient with Wolff-Parkinson-White syndrome who underwent an electrophysiologic study (EPS) and ablation using temperature-guided radiofrequency current for atrial fibrillation with a shortest preexcited RR interval of 160 ms. Detailed EPS and mapping demonstrated an unusual, complex left-sided accessory pathway, with the two distinct branches having two remote atrial insertions and a narrow common ventricular isthmus associated with the manifestation of atrial double potentials recorded from the coronary sinus. Simple ablation at the left lateral side from the ventricular aspect completely eliminated complex accessory pathway conduction, resulting in the disappearance of atrial double potentials.

Radiofrequency catheter ablation of a right atriofascicular (Mahaim) and two atrioventricular (Kent) accessory pathways in a single session.

This report describes the case of a 19-year-old patient with Ebstein's anomaly, who had an unusual combination of a right atriofascicular (Mahaim) and two ipsilateral right atrioventricular (Kent) accessory pathways participating in three types of antidromic and orthodromic reciprocating tachycardias in the absence of retrograde conduction over the bundle of His-atrioventricular node axis. All three pathways were ablated in a single session using temperature-guided radiofrequency current.

[Electrocardiographic Holter monitoring in patients with ventricular pre-excitation: possibilities of its uses and pitfalls].

Holter monitoring (HM) of the electrocardiogram (ECG) is used currently for the management of patients with ventricular preexcitation (PE). It makes it possible to detect inconstant PE which is considered a marker of a favourable clinical development. HM of ECG is not suitable for the detection of paroxysmal supraventricular tachycardias (PSVT) in patients with PE, as their presence is detected only exceptionally during HM.

[Analysis of arrhythmias using Holter electrocardiographic monitoring in patients with ventricular preexcitation].

Background: It is known that patients with preexcitation of ventricles (PE) have a predisposition to paroxysmal supraventricular tachyarrhythmias (PSVT). There is a relatively small amount of knowledge concerning the occurrence and clinical significance of other disturbances of the cardiac rhythm in these patients.

Objectives: 1.

Areas of slow conduction in atrial re-entrant tachycardia: a case report and review of the literature.

An electrophysiologic study of atrial tachycardia is presented. During tachycardia, transient entrainment and sinus rhythm, two patterns of persistent double potentials in the high right atrium and fragmented activity in the low atrial septum were observed. No activity was recorded from multiple areas of the right atrium with endocardial mapping during sinus rhythm.

[Is Helicobacter pylori gastritis a macroscopic diagnosis?].

In a prospective study, gastroscopy and biopsies from the gastric antrum and body were undertaken in 100 consecutive patients (67 women, 33 men; mean age 58.6 [11-90] years) with unknown Helicobacter pylori status. None had been on any bacteria-suppressing drugs.

Triggered activity as the proposed mechanism of left atrial tachycardia induced by premature ventricular beats.

In a 57-year-old woman with complex ventricular ectopy, a paroxysmal supraventricular tachycardia initiated by premature ventricular beats is presented. She underwent an electrophysiologic study. The tachycardia origin was localised to the left atrium.

Parasympathetic overactivity and its evaluation in patients with sinus nodal dysfunction.

In 17 controls, and 17 patients with sinus nodal dysfunction, an electrophysiologic study was made of sinus nodal function and atrioventricular nodal conduction in the basal state. The study was then repeated in all patients after atropine. The heart rate, mean sinus cycle length, variations of sinus cycle length, sinus node recovery times, sinuatrial conduction time, AH interval, and atrioventricular nodal Wenckebach threshold were significantly different in patients from those of controls.

[Ventricular tachycardia in patients with arrhythmogenic right ventricular dysplasia. Electrophysiologic characteristics and testing of the effectiveness of anti-arrhythmia therapy].

The authors present a clinical and electrophysiological characteristic in two cases of symptomatic sustained ventricular tachycardia (VT) with a QRS morphology of left bundle branch block, refractory to common antiarrhythmic treatment. It was confirmed that the mechanism of this arrhythmia associated with a high risk of sudden death is the reentry phenomenon and the authors analyzed its relationship to arrhythmogenic dysplasia of the right ventricle. In a way uncommon in our literature the authors demonstrate the importance of comprehensive electrophysiological examination in these serious cases and its usefulness in confirming the origin of VT in the right ventricle, its importance for mapping the accurate localization of tachycardia and the investigation of effectiveness of drugs and the evaluation of aptness of non-pharmacological treatment.

Retrograde dual atrioventricular nodal pathway in patients with atrioventricular reciprocating tachycardia using concealed accessory pathways.

We present electrophysiological studies in two patients with atrioventricular reciprocating tachycardias. The first patient had anterograde dual atrioventricular nodal pathways with a right-sided concealed accessory pathway. The retrograde atrioventricular nodal pathway showed evidence suggestive of slow pathway properties.

Comparison of indirect and direct methods for determination of sinoatrial conduction time.

We have performed an electrophysiologic study (EPS) in 18 subjects (mean age 21 +/- 17 years) with normal sinus node function (group A) and in 15 patients (mean age 43 +/- 26 years) with sinus node dysfunction (group B). Three extrastimulus methods (both Strauss and Kirkorian methods and our modification of the extrastimulus method) were carried out in 31 patients of both groups and sinoatrial conduction times (SACTSTR, SACTKIR,SACTMOD) could be estimated in 27 of them. SACT by the Narula method (SACTNAR) was assessed in 25 patients of both groups.