Clinical Investigation
Native and Paced QRS Duration in Right Ventricular Apex Paced Patients

https://doi.org/10.1016/j.cardfail.2009.10.021Get rights and content

Abstract

Background

The value between paced QRS duration (pQRSd) and native QRS duration (nQRSd) in paced population has not been compared. The relation between nQRSd and pQRSd remains undefined now.

Methods and Results

A total of 310 right ventricular apex (RVA) paced patients were enrolled. The correlation coefficients between nQRSd and pQRSd to left ventricular (LV) dimensions and ejection fraction (LVEF) were calculated and then compared. The association between pQRSd and nQRSd was examined. pQRSd was better correlated with LVDD, LVDS, and LVEF than nQRSd in all patients or patients with no intraventricular conduction block (NIVCB, n = 136) or complete right bundle-branch block (CRBB, n = 86) (all P < .01). pQRSd was positively correlated with nQRSd in NIVCB, CRBB, and complete left bundle-branch block (CLBB, n = 45) patients (r = 0.408, 0.465, and 0.766, respectively; all P < .001). However, pQRSd was not different between NIVCB, CRBB, and CLBB patients (P > .05) after adjusting for LVEF and LV dimensions.

Conclusions

pQRSd is superior to nQRSd in terms of reflecting LV structures and function in RVA-paced patients. Bundle branch block (BBB) has no significant effect on pQRSd and thus further studies are needed to clarify whether BBB is an independent risk factor for the development of heart failure after RVA pacing.

Section snippets

Patients Selection

Consecutive patients referred to our department for routine pacemaker interrogation from November 2007 to May 2009 were enrolled in study. The inclusion criteria were as follows: the ventricular pacemaker lead should be placed at the RVA; paced QRS complex could be seen in each lead in standard electrocardiography (ECG) for correct pQRSd measurement; patients with VVI(R) pacemakers or patients implanted with DDD(R) pacemakers having high or third-degree atrioventricular block; in patients with

Patients' Characteristics

From 1124 patients referred to our department for routine pacemaker interrogation, 310 patients who met the inclusion criteria were enrolled in this study. The patients' characteristics were given in Table 1. On the aspect of native QRS complex, 136 patients had NIVCB, 86 had CRBB, 45 had CLBB, 13 had incomplete right bundle-branch block, 8 had incomplete left bundle-branch block, and 21 had unclassified intraventricular conduction block. The nQRSd, pQRSd, LV diameters, and LVEF in NIVCB, CRBB,

Discussion

Our study confirmed that pQRSd and nQRSd were correlated with LV structures and function in RVA-paced patients and found that pQRSd was superior to nQRSd in terms of reflecting LV structures and function, particularly in NIVCB and CRBB patients. These results can be explained by the difference between pQRSd caused by RVA pacing and nQRSd activated by normal sinus rhythm. During normal sinus rhythm, the electrical activation conducts through the His Purkinje System (HPS) and then ventricular

Conclusion

In RVA paced patients, both pQRSd and nQRSd are correlated with LV structures and function, but pQRSd is superior to nQRSd in terms of reflecting LV structures and function. nQRSd is positively correlated with pQRSd in NIVCB or CRBBB or CLBBB patients. However, BBB has no significant effect on pQRSd after adjustment for LVEF and LV dimensions. Further studies are needed to clarify whether BBB is an independent risk factor for the development of HF after RVA pacing.

References (21)

There are more references available in the full text version of this article.

Cited by (6)

  • Prolonged Ventricular Conduction and Repolarization During Right Ventricular Stimulation Predicts Ventricular Arrhythmias and Death in Patients With Cardiomyopathy

    2017, JACC: Clinical Electrophysiology
    Citation Excerpt :

    RV-paced QRS duration has been associated with the degree of myocardial disease. Sumiyoshi et al. (21) evaluated paced QRS duration in patients with pacemakers and found that a paced QRS duration >180 ms was associated with decreased LV function compared with patients with a paced QRS duration ≤180 ms. Similarly, other investigators reported that in patients with implantable devices, longer paced QRS duration is associated with more severe cardiac dysfunction and is a better marker of subjacent cardiomyopathy than is baseline QRS duration (22). In addition, patients with cardiomyopathy, heart block, and a paced QRS duration >190 ms were more likely to have clinical heart failure events than those with a shorter paced QRS duration (23), and a prolonged paced QRS duration at pacemaker implantation was associated with a higher incidence of heart failure hospitalization (24).

The authors have no conflicts to disclose.

Drs Wenzhi Pan and Yangang Su contributed equally to this work.

View full text