J.A. Salerno-Uriarte

Fast pathway ablation in a patient with iterative atrioventricular nodal reentrant tachycardia and prolonged PR interval

A safe approach to radiofrequency catheter ablation is still unclear and not well defined in patients with AV nodal reentrant tachycardia and prolonged PR interval. In our study, a patient with iterative AV nodal reentrant tachycardia and prolonged PR interval underwent fast pathway radiofrequency catheter ablation. By mapping Kochs triangle, the earliest retrograde atrial activation area was localized. Radiofrequency energy was delivered here with the interruption of tachycardia with no complications.

Spontaneous incessant AV reentrant tachycardia related to left bundle branch block and concealed left-sided accessory AV pathway.

Incessant Tachycardia in WPW Syndrome. Three patients in whom permanent AV reentrant tachycardia became the clinical manifestation of Wolff‐Parkinson‐White syndrome are described. The substrate for the arrhythmia was created by coexistence of a concealed left‐sided accessory pathway and an ipsilateral bundle branch block. Pharmacology therapy in all three patients failed to control the tachycardia, which in two cases led to severe left ventricular failure. After successful radio frequency ablation of the accessory pathway (in two) or A V junction (in one), left ventricular function gradually returned to normal.

12-Lead Remote ECG Monitoring in Follow-Up of Pulmonary Vein Ablation

Aim to assess usefulness of a 12-lead remote ECG monitoring system (12LRECG) in the follow-up of pts after pulmonary vein ablation (PVA) for atrial fibrillation (AF). Method 5 consecutive pts (4 M, age 52±13 yrs) who underwent PVA for recurrent, drug refractory AF. Four pts with idiopathic AF, one with postsurgical AF for atrial septal defect closure. The 12LRECG is a portable recording device (Aerotel, Heart View 12), transtelephonically downloadable through a call center (Tesan, Vicenza) to a server (Globalcardio), accessible via Internet to authorized personnel. The pts recorded an ECG every day for 40 days after discharge, and in case of palpitations. Results 222 ECG were recorded, all of good quality. AF was documented in 3/5 pts. Pt 1, in a single 12LRECG, with spontaneous sinus rhythm restoration. Pt 2, recurrence of asymptomatic persistent AF preceded by atrial bigeminism from the right superior pulmonary vein. Pt 3, with postsurgical AF, multiple recurrences of paroxysmal AF with few symptoms. Conclusions The 12LRECG is a useful system for the follow-up of pts after PVA, easy to use and with a quality good enough in discriminating arrhythmia morphology.

7. Pulmonary Veins: Anatomy and Transcatheter Electrical Isolation

Aim to assess usefulness of a 12-lead remote ECG monitoring system (12LRECG) in the follow-up of pts after pulmonary vein ablation (PVA) for atrial fibrillation (AF). Method 5 consecutive pts (4 M, age 52±13 yrs) who underwent PVA for recurrent, drug refractory AF. Four pts with idiopathic AF, one with postsurgical AF for atrial septal defect closure. The 12LRECG is a portable recording device (Aerotel, Heart View 12), transtelephonically downloadable through a call center (Tesan, Vicenza) to a server (Globalcardio), accessible via Internet to authorized personnel. The pts recorded an ECG every day for 40 days after discharge, and in case of palpitations. Results 222 ECG were recorded, all of good quality. AF was documented in 3/5 pts. Pt 1, in a single 12LRECG, with spontaneous sinus rhythm restoration. Pt 2, recurrence of asymptomatic persistent AF preceded by atrial bigeminism from the right superior pulmonary vein. Pt 3, with postsurgical AF, multiple recurrences of paroxysmal AF with few symptoms. Conclusions The 12LRECG is a useful system for the follow-up of pts after PVA, easy to use and with a quality good enough in discriminating arrhythmia morphology.

Complex Supraventricular Tachycardia Ablation: What Is the Role of Alternative Technology?

Radiofrequency catheter ablation is a safe and effective treatment for curing supraventricular tachycardias (SVT), including those related to different forms of atrioventricular (AV) nodal reentry and to the Wolff-Parkinson-White syndrome. Although this treatment is largely considered as a first-line therapy for these tachycardias, under some circumstances the safety and/or the effectiveness of the procedure might be endangered. This review will focus on the difficulties that can be met during SVT catheter ablations, and on the role of special tools and new technologies in improving the success rate and reducing the complications.

Ablation of Antero-Septal and Intermediate Septal Accessory Pathways: How Safe Is It? How Can One Minimize the Risk of AV Block?

The current goal of radiofrequency catheter ablation of supraventricular tachycardias is to cure a large cohort of patients with a primary success rate close to 100% and a complication and recurrence rate close to 0%. In this setting, the ablation of the atrioventricular (A-V) accessory pathway in the triangle of Koch may still represent a grey area, since the strict anatomical relationship between the bypass tract and the A-V node-His bundle may affect the feasibility and safety of the procedure. Consequently, the only rationale for successful ablation with no complication in this area relies on the assumption that the accessory pathway is more sensitive to radiofrequency energy delivery than the normal A-V conduction system [1]. The risk of damaging the normal A-V conduction pathway and of inducing a complete A-V block requiring a permanent pacemaker has been pointed out by both early [2, 3] and recent [4–6] reports, although successful and safe ablation has been described in limited series of cases [7, 8], even with “para-hissian” accessory pathways [1]. Moreover, in the risk/benefit ratio of ablation of by-pass tracts in the Koch’s triangle one must consider not only failure and the risk of permanent complete A-V block, but also the theoretical possibility of creating an incessant reentrant circuit by partially damaging both the accessory pathway and the A-V node conduction.

“Incisional” Reentrant Atrial Tachycardia: How to Prevent and Treat It?

Patients submitted to cardiac surgery for correction of congenital or acquired heart diseases may subsequently experience several types of atrial tachyarrhythmias [1–4]. Most of these are macroreentrant atrial tachycardias strictly related to the presence of scars, prosthetic materials, or conduits and have therefore been named “incisional” or “scar-related” atrial tachycardias. Although their electrocardiographic characteristics may resemble those of atrial flutter, slight differences in P wave morphology and tachycardia cycle length are present and should be identified in order to formulate the correct diagnosis. “Incisional” atrial tachycardia may occur at widely variable times after the operation, most frequently in patients submitted to septal atrial defect repair and Fontan or Mustard procedures for tricuspid atresia or great vessel transposition correction, respectively. The true prevalence of these arrhythmias is unknown; small retrospective series reported a prevalence of 32–57% after the Fontan procedure [4, 6, 7] and about 15% after the Mustard operation [3, 8].

Prolonged or Failed Attempts at RF Ablation of Accessory Pathways: What Are the Causes?

In 1997 almost the entire population with arrhythmias related to the presence of an anomalous AV pathway (AP) is treated successfully by radiofrequency catheter ablation (RF-CA) without excessive difficulty, but in some cases a very prolonged procedure or a second session or both are required to obtain a successful outcome [1].