Open AccessElectrocardiographic predictors of validated right ventricular outflow tract septal pacing for correct localization of transthoracic echocardiography
Author(s) -
Wei Huiqiang,
Tang Jiaojiao,
Chen Dongli,
Zhang Qianhuan,
Liang Yuanhong,
Liu Lie,
Wu Shulin,
Lin Chunying,
Yang Zhiming,
Chai Chanjuan
Publication year - 2018
Publication title -
clinical cardiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.263
H-Index - 72
eISSN - 1932-8737
pISSN - 0160-9289
DOI - 10.1002/clc.22873
Subject(s) - medicine , qrs complex , cardiology , ventricular outflow tract , lead (geology) , electrocardiography , ventricular pacing , heart failure , geomorphology , geology
Background Electrocardiographic (ECG) characteristics of true right ventricular outflow tract (RVOT) septal pacing have not been clearly demonstrated. Hypothesis We hypothesized that ECG parameters would help operators differentiate true RVOT septum from non‐septal septum. Methods We analyzed 151 patients who underwent pacemaker implantation with a ventricular lead in the RVOT. Transthoracic echocardiographic (TTE) determination of pacing sites was applied in all patients after implantation. A 12‐lead ECG was recorded during forced ventricular pacing. Results According to TTE orientation, pacing at the RVOT septum was achieved in 94 patients (62.3%). Compared with nonseptal pacing, septal pacing had significantly shorter QRS duration (139.2 ± 18.5 ms vs 155.5 ± 14.7 ms; P < 0.001). More frequent negative or isoelectric QRS vector in lead I (76% vs 32%; P < 0.001), lead II/III R‐wave amplitude ratio < 1 (52% vs 25%; P = 0.001), and aVR/aVL QS‐wave amplitude ratio < 1 (59% vs 32%; P = 0.001) were observed in septal pacing. Transitional zone (TZ) score (3.8 ± 0.96 vs 4.2 ± 0.90; P = 0.004) and TZ index (0.3 ± 0.5 vs 0.6 ± 0.7; P = 0.008) were significantly lower in septal pacing than in nonseptal pacing, respectively. In multivariate analysis, paced QRS duration and negative or isoelectric QRS vector in lead I independently predicted RVOT septal pacing ( P < 0.001). At ROC curve analysis, paced QRS duration ≤145 ms identified RVOT septal pacing with 85.1% sensitivity and 78.9% specificity. Conclusions This study reveals the heterogeneity of lead placement within the RVOT. Narrower paced QRS duration and negative or isoelectric QRS vector in lead I independently predict RVOT septal pacing.