Septal Lead Implantation for the Reduction of Paced QRS Duration Using Passive‐Fixation Leads

Abstract

In 120 consecutive patients with standard pacing indications, we tested the feasibility of RV septal lead implantation technique guided by surface ECG and the degree to which this technique reduces paced QRS duration compared to RV apical stimulation when passive-fixation leads are used. During implantation, an ECG was recorded with a paper speed of 100 mm/s using the orthogonal Frank leads, and QRS was measured from the earliest to the latest deflection in any of the Frank leads. Pace-mapping of the septum was performed until QRS was minimal. The lead was attached, where QRS, pacing threshold, lead impedance, and EGM amplitude provided the best compromise. An average of 3.7 +/- 2.5 attempts (range 1-18, median 7) was needed until a final implantation site was found. There were no technical problems during implantation. QRS could be reduced by 5-55 ms (mean delta QRS 19 +/- 11 ms) in 83 (69%) of 120 patients. In 22 (18%) patients, QRS was identical with apical and septal pacing, and in 15 (13%) patients, QRS was 5-20 ms (10 +/- 4) longer despite septal stimulation. Average QRS was significantly shorter during septal pacing compared with apical pacing (151 +/- 20 vs 162 +/- 23 ms, P < 0.001). There was a tendency towards greatest QRS reduction when the high septum was stimulated (22 +/- 11 ms reduction) as compared with mid- (18 +/- 11 ms) or apical parts of the RV septum (16 +/- 10 ms). QRS reduction was most likely if apical QRS width was > 170 ms (P = 0.0002), and there was an inverse correlation between apical QRS and delta QRS (r = 0.53, P < 10(-7)). During a mean follow-up of 14 months, there was no pacing or sensing problem and no lead dislodgment occurred.

Optimizing the pacing site in the ventricular septum by fluoroscopy and morphology of the paced QRS complex

“…The criteria for the final selection of the septal site are the paced QRS vector or duration. The appropriateness of the decision to implant the lead in the RVOT septum based on paced QRS morphology was confirmed by the results of clinical trials 3,7,18 . In both the short and medium term, pacing navigated in the RVOT by paced QRS morphology, compared with standard RVA pacing, was more beneficial, as confirmed by the lower incidence of myocardial perfusion defects and the absence of negative trends in LV ejection fraction 3 .…”

Permanent Cardiac Pacing in Adults with High Grade Atriovetricular Block and Preserved Left Ventricular Function: Optimal Mode and Site of Pacing

“…Previous investigations of alternative pacing sites have yielded inconsistent results (Mera et al, 1999;Giudici et al, 1997;Bourke et al, 2002;Victor et al, 2006;Kypta et al, 2008;Dabrowska-Kugacka et al, 2009;Tse et al Europace 2009;Victor et al, 1999) which may be attributable, in part, to the fact that the pacing site was determined on a topological rather than functional basis (Giudici & Karpawich, 1999). Many previous studies (Schwaab et al, 1999;Victor et al, 2006;Yu et al, 2007;Ng et al, 2009;Takemoto et al, 2009;Tse et al, Europace 2009, Gong et al, 2009Leong et al, 2010;Schwaab et al, 2001), have showed that septal pacing induced shorter paced QRS duration than RVA pacing did. These results indicated that RVS pacing resulted in better electric synchrony compared with RVA pacing.…”

“…Indeed from experience, it is very hard to manipulate leads with fluoroscopy at 40° either from the left or right sided approach. However, electrocardiographic criteria such as negative deflection of lead I and positive initial R-waves of the paced ventricular complex in leads II and III ( Schwaab et al, 2001;McGavigan et al,2006;Lieberman et al, 2004;Balt et al, 2010) or the narrowest paced QRS complex available during the mapping of the interventricular septum (Tse et al, 2002;Tse et al, 2009a;Tse et al, 2009b;Schwaab et al, 2001), were not used uniformly. Tse et al and Mera et al (Mera et al, 1999) have postulated that the paced QRS duration is a practical indicator for determining the optimal RV pacing site.…”

“…Tse et al and Mera et al (Mera et al, 1999) have postulated that the paced QRS duration is a practical indicator for determining the optimal RV pacing site. However, Schwab et al (Schwaab et al, 2001) have found the detailed mapping of the RV with precise measurements of QRS duration has been found to be impractical. This lack of uniform definitions of where the alternate RV sites actually lie and the inadequacy of tools to consistently reach these locations and verify correct placement may account for the variability in lead positioning within the RVS and may have contributed to the mixed results regarding the long-term hemodynamic benefits of RVS pacing (Lieberman et al, 2004;Balt et al, 2010;Iaizzo et al, 2004).…”

“…In the daily practice, the standard approach of septal site is based generally on only fluoroscopic images during the implantation procedure. Several studies have demonstrated the feasibility, and the safety of alternative pacing sites (Rosso et al, 2010;Vlay et al, 2006;Medi & Mond, 2009, Schwaab et al, 2001). With active fixation technology, lead placement and stability in the RVS are no longer a problem.…”