Idiopathic premature ventricular contractions and ventricular tachycardias originating from the vicinity of tricuspid annulus: results of radiofrequency catheter ablation in thirty-five patients

Abstract

Background: In recent years, catheter ablation has increasingly been used for ablation of idiopathic premature ventricular complexes (PVCs) or ventricular tachycardias (IVTs). However, the mapping and catheter ablation of the arrhythmias originating from the vicinity of tricuspid annulus (TA) may not be fully understood. This study aimed to investigate electrophysiologic characteristics and effects of radiofrequency catheter ablation (RFCA) for patients with symptomatic PVCs and IVTs originating from the vicinity of TA.

Methods: Characteristics of body surface electrocardiogram (ECG) and electrophysiologic recordings were analyzed in 35 patients with symptomatic PVCs/ IVTs originating from the vicinity of TA. RFCA was performed using pace mapping and activation mapping.

Results: Among the 35 patients with PVCs/IVTs arising from the vicinity of TA, complete elimination of PVCs/IVTs could be achieved by RFCA in 32 patients (success rate 91.43%) during a median follow-up period of 21 months. PVCs/IVTs originating from the vicinity of TA had distinctive ECG characteristics that were useful for identifying the precise origin. An rS pattern was recorded in lead V1 in 93.1% of patients with PVCs/IVTs from the free wall of TA, vs 16.7% of patients with PVCs/IVTs from the septal TA, whereas a QS pattern in lead V1 occurred in 83.3% of patients with PVCs/IVTs from the septal TA vs 6.9% of patients with PVCs from the free wall of the TA. The precordial R wave transition occurred by lead V3 or earlier in all patients with PVCs/IVTs originating from the septal portion of the TA, as compared to transition beyond V3 in all patients with PVCs/IVTs from the free wall of the TA.

Conclusions: RFCA is an effective curative therapy for symptomatic PVCs/IVTs originating from the vicinity of TA. There are specific characteristics in ECG and the ablation site could be located by ECG analysis.

Figure 1

In the left anterior oblique (LAO) projection, the tricuspid annulus was viewed as a clock face, that was divided into 6 portions: anteroseptum (approximately 12 o’clock to 2 o’clock), midseptum (approximately 2 o’clock to 4 o’clock), posteroseptum (approximately 4 o’clock to 6 o’clock position), anterolateral portion (approximately 10 o’clock to 12 o’clock position), midlateral portion (approximately 8 o’clock to 10 o’clock position), posterolateral portion (approximately 6 o’clock to 8 o’clock position).

Figure 2

Recordings obtained at the ablation site for patient number 19 in the Table 2. (A) 12-lead ECG characteristic. (B) The local ventricular activation time recorded at the successful ablation site that preceded the onset of the QRS complex was 30 ms. (C) Pace map at the successful ablation site. (D) The fluoroscopic position of the successful ablation site. ABL, ablation catheter; CS, coronary sinus; RAO, right anterior oblique projection; LAO, left anterior oblique projection.

Figure 3

Recordings obtained at the ablation site for patient number 3 in the Table 2. (A) 12-lead ECG characteristic. (B) Pace map at the successful ablation site. (C)The local ventricular activation time recorded at the successful ablation site that preceded the onset of the QRS complex was 33 ms. (D) The fluoroscopic position of the successful ablation site. ABL, ablation catheter; RAO, right anterior oblique projection; LAO, left anterior oblique projection.

Figure 4

Recordings obtained at the ablation site for patient number 4 in the Table 2. (A) 12-lead ECG characteristic at a paper speed of 25 mm/s. (B) 12-lead ECG characteristic at a paper speed of 100 mm/s. (C) Pace map at the successful ablation site. (D) The fluoroscopic position of the successful ablation site. ABL, ablation catheter; RAO, right anterior oblique projection; LAO, left anterior oblique projection

Figure 5

Representative 12-lead ECG characteristics of ventricular arrhythmia originating from Tricuspid annulus.

Figure 6

Differences in (A) rS pattern in lead V1, (B) QS pattern inlead V1, and (C) precordial R-wave transition occurring by lead V3 between PVCs/IVTs originating from the septal portion of the tricuspid annulus (Septal origin) and those originating from the free-wall portion of tricuspid annulus (FW origin).