Diagnostic Value of the Modified Limb Lead System in Localizing the Origin of Outflow PVCs

Document Type : Original Article

Authors

1 Department of Cardiac Electrophysiology, Rajaie Cardiovascular Medical and Research Center, Iran University of Medical Sciences, Tehran, IR Iran.

2 Department of Cardiology, Mousavi Hospital, Zanjan University of Medical Sciences, Zanjan, IR Iran.

3 Department of Community Medicine, School Medicine, Zanjan University of Medical Sciences, Zanjan, IR Iran.

4 Department of Pacemaker and Electrophysiology, Rajaie Cardiovascular Medical and Research Center, Iran University of Medical Sciences, Tehran, IR Iran.

Abstract

Background: The most common subgroup of premature ventricular contractions (PVCs) is the idiopathic outflow tract premature ventricular contraction (IOT-PVC). The radiofrequency catheter ablation of PVCs is the choice of treatment in drug-resistant or intolerant patients. There are many different ways to localize PVC origins, some of which pose a challenge. We hypothesized that changing limb electrode locations can help us localize IOT-PVCs.
 
Methods: This cross-sectional study was done in Rajaie Cardiovascular Medical and Research Center, Tehran, Iran, from 2019 through 2020. In all patients, in addition to surface electrography, 3 limb electrodes were placed at 3 spaces: right parasternal at the second intercostal space, left parasternal at the second intercostal space, and the tip of the left scapula. Three new vectors were achieved, which were then compared with the same-named limb vectors.
 
Results: The study population consisted of 102 patients. The voltage of the R and S waves of PVCs were compared in modified and conventional leads. All the formulas used had a statistically significant relationship (P<0.007) with the origin of PVCs other than IMR/ICR and IMR-S/ICR-S.
 
Conclusions: Comparison of the R and S waves of PVCs in modified lead II and III with the same-named conventional leads can yield the best results to estimate the origin of PVCs. The most useful formulas concerning sensitivity and specificity are IIMR/IICR and IIIMR/IIICR. The absence of notching at modified lead II can be a predictor of successful PVC ablation. (Iranian Heart Journal 2022; 23(4): 29-37)

Keywords


  1. Ahn MS. Current Concepts of Premature Ventricular Contractions. Journal of lifestyle medicine. 2013; 3(1):26-33.
  2. Park KM, Im SI, Park SJ, Kim JS, On YK. Risk factor algorithm used to predict frequent premature ventricular contraction-induced cardiomyopathy. International journal of cardiology. 2017; 233:37-42.
  3. Wang JS, Shen YG, Yin RP, Thapa S, Peng YP, Ji KT, et al. The safety of catheter ablation for premature ventricular contractions in patients without structural heart disease. BMC cardiovascular disorders. 2018; 18(1):177.
  4. Zheng J, Fu G, Anderson K, Chu H, Rakovski C. A 12-Lead ECG database to identify origins of idiopathic ventricular arrhythmia containing 334 patients. Scientific Data. 2020; 7(1):98.
  5. Qin F, Zhao Y, Bai F, Ma Y, Sun C, Liu N, et al. Coupling interval variability: A new diagnostic method for distinguishing left from right ventricular outflow tract origin in idiopathic outflow tract premature ventricular contractions patients with precordial R/S transition at lead V3. International journal of cardiology. 2018; 269:126-32.
  6. Svehlikova J, Teplan M, Tysler M. Geometrical constraint of sources in noninvasive localization of premature ventricular contractions. Journal of electrocardiology. 2018; 51(3):370-7.
  7. Lin D, Ilkhanoff L, Gerstenfeld E, Dixit S, Beldner S, Bala R, et al. Twelve-lead electrocardiographic characteristics of the aortic cusp region guided by intracardiac echocardiography and electroanatomic mapping. Heart rhythm. 2008; 5(5):663-9.
  8. Dixit S, Gerstenfeld EP, Callans DJ, Marchlinski FE. Electrocardiographic patterns of superior right ventricular outflow tract tachycardias: distinguishing septal and free-wall sites of origin. Journal of cardiovascular electrophysiology. 2003; 14(1):1-7.
  9. Shimizu W. Arrhythmias originating from the right ventricular outflow tract: how to distinguish "malignant" from "benign"? Heart rhythm. 2009; 6(10):1507-11.
  10. Hachiya H, Aonuma K, Yamauchi Y, Harada T, Igawa M, Nogami A, et al. Electrocardiographic characteristics of left ventricular outflow tract tachycardia. Pacing and clinical electrophysiology: PACE. 2000; 23(11 Pt 2):1930-4.
  11. Yoshida N, Yamada T, McElderry HT, Inden Y, Shimano M, Murohara T, et al. A novel electrocardiographic criterion for differentiating a left from right ventricular outflow tract tachycardia origin: the V2S/V3R index. Journal of cardiovascular electrophysiology. 2014; 25(7):747-53.
  12. Xie S, Kubala M, Liang JJ, Hayashi T, Park J, Padros IL, et al. Lead I R-wave amplitude to differentiate idiopathic ventricular arrhythmias with left bundle branch block right inferior axis originating from the left versus right ventricular outflow tract. Journal of cardiovascular electrophysiology. 2018; 29(11):1515-22.
  13. Yamada T, Yoshida N, Murakami Y, Okada T, Muto M, Murohara T, et al. Electrocardiographic characteristics of ventricular arrhythmias originating from the junction of the left and right coronary sinuses of Valsalva in the aorta: the activation pattern as a rationale for the electrocardiographic characteristics. Heart rhythm. 2008; 5(2):184-92.
  14. Bala R, Garcia FC, Hutchinson MD, Gerstenfeld EP, Dhruvakumar S, Dixit S, et al. Electrocardiographic and electrophysiologic features of ventricular arrhythmias originating from the right/left coronary cusp commissure. Heart rhythm. 2010; 7(3):312-22.
  15. Alasady M, Singleton CB, McGavigan AD. Left ventricular outflow tract ventricular tachycardia originating from the noncoronary cusp: electrocardiographic and electrophysiological characterization and radiofrequency ablation. Journal of cardiovascular electrophysiology. 2009; 20(11):1287-90.