Catheter ablation of idiopathic left ventricular tachycardia associated with a false tendon

Catheter ablation of premature ventricular complexes associated with left ventricular false tendons

BACKGROUND

Clinical studies have suggested that there is a significant correlation between left ventricular (LV) false tendon and premature ventricular complexes (PVCs).

OBJECTIVE

This study aimed to investigate the electrophysiological characteristics and the outcome of radiofrequency catheter ablation (RFCA) for this category of PVCs.

METHODS

From a total of 2284 patients with idiopathic PVCs who underwent catheter ablation at 6 institutions in China, intracardiac echocardiography (ICE) was used during the procedure in 346 cases; 10 patients (2.9%) with PVCs associated with false tendon were retrospectively reviewed and enrolled in the present study. Activation mapping and pace mapping were performed to localize the origin of PVCs. ICE was used in all patients. If the false tendon was directly visualized and identified, we attempted to identify the distinct relationship with the PVC origin.

RESULTS

The PVCs were successfully eliminated by ablation in all patients. The target sites were confirmed to be related to false tendon. The origin of PVCs was located at the attachment of the false tendon to the papillary muscle, LV septum, or LV apex. At the target site, high-frequency Purkinje potentials were observed preceding local ventricular activation in 7 patients.

CONCLUSION

LV false tendon can be associated with PVCs, which can be cured by RFCA. An ICE-guided electroanatomical approach should be considered to improve the safety and feasibility of this procedure.

Anatomical Basis for the Cardiac Interventional Electrophysiologist

The establishment of radiofrequency catheter ablation techniques as the mainstay in the treatment of tachycardia has renewed new interest in cardiac anatomy. The interventional arrhythmologist has drawn attention not only to the gross anatomic details of the heart but also to architectural and histological characteristics of various cardiac regions that are relevant to the development or recurrence of tachyarrhythmias and procedural related complications of catheter ablation. In this review, therefore, we discuss some anatomic landmarks commonly used in catheter ablations including the terminal crest, sinus node region, Koch's triangle, cavotricuspid isthmus, Eustachian ridge and valve, pulmonary venous orifices, venoatrial junctions, and ventricular outflow tracts. We also discuss the anatomical features of important structures in the vicinity of the atria and pulmonary veins, such as the esophagus and phrenic nerves. This paper provides basic anatomic information to improve understanding of the mapping and ablative procedures for cardiac interventional electrophysiologists.

Positional Ventricular Tachycardia

A 60-year-old man showed nonsustained repetitive monomorphic VT in the left lateral position, but this was terminated by deep inspiration. Echocardiography and MRI demonstrated a false tendon extending from the apex to the basal septum where the VT could have originated. Spontaneous remission occurred during the 16-year follow-up.

Ventricular arrhythmias in normal hearts

Idiopathic ventricular tachycardia (VT) is characterized by two predominant forms. The most common form originates from the right ventricular outflow tract and presents as repetitive monomorphic VT or exercise-induced VT. The tachycardia is adenosine sensitive and is thought to be because of cAMP-mediated triggered activity. The other major form of idiopathic VT is owing to verapamil-sensitive intrafascicular re-entrant tachycardia, which most often originates in the region of the left posterior fascicle. Both forms of idiopathic VT can be readily treated with radiofrequency catheter ablation.