Article Text

PDF
Original article
Dyssynchrony, contraction efficiency and regional function with apical and non-apical RV pacing
  1. Makoto Saito1,
  2. Gerry Kaye2,3,
  3. Kazuaki Negishi1,
  4. Nick Linker4,
  5. Michael Gammage5,
  6. Wojciech Kosmala1,6,
  7. Thomas H Marwick1,
  8. on behalf of the Protect-Pace investigators
  1. 1Menzies Institute for Medical Research, Hobart, Tasmania, Australia
  2. 2Princess Alexandra Hospital, Brisbane, Queensland, Australia
  3. 3University of Queensland, Brisbane, QLD 4072
  4. 4James Cook University Hospital, Cleveland, UK
  5. 5University of Birmingham, Birmingham, UK
  6. 6Wroclaw Medical University, Wroclaw, Poland
  1. Correspondence to Dr Thomas H Marwick, Menzies Institute for Medical Research, Private Bag 23, Hobart, TAS 7000, Australia; Tom.Marwick{at}utas.edu.au

Abstract

Background Recent work has shown no difference in change of LVEF between RV apical (RVA) pacing and non-RVA pacing in patients with normal LV function. We hypothesised that a more sensitive marker (global longitudinal strain, GLS) could identify a detrimental effect of RVA and that assessment of deformation could identify whether dyssynchrony, contraction inefficiency and regional LV impairment were responsible for functional changes.

Methods In this substudy of Protect-PACE (The Protection of Left Ventricular Function During Right Ventricular Pacing. Does Right Ventricular High-septal Pacing Improve Outcome Compared With Right Ventricular Apical Pacing?), a randomised controlled trial of RVA and non-RVA pacing in pacemaker-dependent patients with preserved EF, 145 patients (76 with RVA) with echocardiograms of sufficient quality underwent measurement of LV longitudinal strain (GLS) from speckle tracking just after implantation and at 2 years. LV dyssynchrony, discoordination and regional apical longitudinal strain were also measured.

Results Pacing was associated with reduced GLS after 2 years, although 2-year GLS was lower in RVA (−13.9±4.1 vs −15.5±4.6, p=0.02). RVA was an independent correlate of ΔGLS, although there was a minor difference in ΔGLS between the RVA and non-RVA groups (−1.8±3.6 vs −0.8±3.4%, p=0.07), reflecting impairment of GLS at baseline in RVA. Apical strain was significantly lower in RVA than those in non-RVA at baseline and 2 years (both p<0.01). Dyssynchrony and discoordination parameters at 2 years also showed significant deterioration in RVA. Apical strain, dyssynchrony and discoordination parameters at 2 years were significantly associated with ΔGLS.

Conclusions Inefficient dyssynchronous contraction and the decrease in apical strain appear to be associated with global LV impairment in RVA.

Trial registration number PROTECT-PACE ClinicalTrials.gov number NCT00461734.

Statistics from Altmetric.com

Request permissions

If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.