Idiopathic ventricular arrhythmia originating from the para‐Hisian area: Prevalence, electrocardiographic and electrophysiological characteristics

Abstract

Background We investigated the prevalence and the electrocardiographic and electrophysiological characteristics of ventricular arrhythmias (VAs) originating from the para‐Hisian area. Methods Among 250 patients with idiopathic VAs, 8 (3.2%) had an ablation site in the para‐Hisian region. For comparison with right ventricular (RV) para‐Hisian VAs (n=6), 27 patients with VAs originating from the posterior RV outflow tract (RVOT) were studied. Results Para‐Hisian VAs had an R wave in leads I and aVL. The VAs originating from the site below the His bundle region were determined to have a superior axis (n=4, 50%). A His potential was recorded at the proximal bipole of the successful ablation site in 6 patients. RV para‐Hisian VAs had a narrower QRS width (114±12 ms vs. 139±12 ms, P=0.003), as well as a higher incidence of R waves in lead aVL (83.3% vs. 0%, P<0.001) and QS waves in lead V1 (83.3% vs. 22.2%, P=0.004) compared to posterior RVOT VAs. A greater R wave amplitude in lead I (1.15±0.34 mV vs. 0.34±0.18 mV, P=0.001) and a smaller R wave amplitude in the inferior leads (0.68±0.23 mV vs. 1.58±0.55 mV, P<0.001), with a higher R wave amplitude ratio in leads II/III (4.2±2.0 vs. 1.1±0.2, P=0.01) were the major ECG characteristics. Conclusions Para‐Hisian VAs have distinctive electrocardiographic features and can be successfully eliminated without disturbance of atrioventricular conduction.

Successful catheter cryoablation for premature ventricular contractions originating from the para‐Hisian region

“…The 12‐lead electrocardiography (ECG) showed tall R waves in I and aVL, in addition to a near‐QS pattern in V1, relatively narrow QRS waves in V1‐2, and a precordial transition zone between V3 and V4 (Figure ). All these findings strongly suggested that the PVCs originated from the right ventricular septum close to the His bundle …”

“…All these findings strongly suggested that the PVCs originated from the right ventricular septum close to the His bundle. 1,2,4,[9][10][11] After informed consent was obtained, a cardiac electrophysiological study was performed with the patient fasting and not taking antiarrhythmic drugs. A 4-Fr hexapolar electrode catheter (Supreme ™ , St. Jude Medical, Inc) was positioned in the His bundle region.…”

Inferior lead discordance in ventricular arrhythmias: A specific marker for certain arrhythmia locations

“…reported that the voltage ratio of leads II and III was 65% versus 97% in patients with RVOT VAs (P < 0.0001) . In another study comparing VAs from the parahisian region (n = 6) and posterior RVOT (n = 27), a greater R wave amplitude in lead I (1.15 ± 0.34 mV vs. 0.34 ± 0.18 mV, P = 0.001), a smaller R wave amplitude in the inferior leads (0.68 ± 0.23 mV vs. 1.58 ± 0.55 mV, P < 0.001), and a higher R wave amplitude ratio in leads II/III (4.2 ± 2.0 vs. 1.1 ± 0.2, P = 0.01) were the major ECG predictors of a parahisian origin . Other distinctive characteristics include a relatively narrow QRS duration, explained by the early engagement of the His Purkinje network, and an RSR’ or RR’ pattern in aVL, a finding that was present in 28.6% of our patients.…”

“…Poor tissue-catheter contact F I G U R E 3 Examples of PVCs with positive/negative (1-6) and negative/positive (7-9) discordance. Mapping showed origin from the parahisian region (1-3), RV moderator band (4-6), and ALPM (7)(8)(9). In comparison with parahisian PVCs, MB PVCs exhibited a wider QRS duration, later precordial transition, and higher prevalence of notching in the inferior leads [Color figure can be viewed at wileyonlinelibrary.com] limits power delivery and may induce frequent ectopy that further complicates catheter stability.…”

“…9% of idiopathic VAs7,8 and share common ECG characteristics with RVOT arrhythmias, such as a LBBB pattern, QS in V1, and an inferior axis. Some additional characteristics may favor an origin from the parahisian area,[7][8][9] including prominent R waves in leads I and aVL and a lower R wave amplitude in lead III than lead II, which are a manifestation of the more posterior and rightward location of the His region within the outflow tract, with subsequent leftward shift of the depolarization vector. In a group of 10 patients with VAs originating near the His bundle, Yamauchi et al reported that the voltage ratio of leads II and III was 65% versus 97% in patients with RVOT VAs (P < 0.0001) 9.…”