Acute effects of dual-chamber pacing on the left ventricular systolic function and relaxation in patients with advanced AV block and sick sinus syndrome

Hsiang Chiang Hsiao, Chen Huan Chen*, Chi Woon Kong, Chun Peng Liu

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

1 Scopus citations

Abstract

Background: Abnormal activation of the ventricles via right ventricular apical pacing deteriorates cardiac function, which may explain the increased mortality of patients with congestive heart failure receiving permanent pacemakers. We hypothesized that pacing at alternative sites may cause less detrimental effects on the cardiac function. Methods: Five symptomatic patients with either advanced AV block (n = 4) or sick sinus syndrome with normal left ventricular (LV) function (n = 1) were studied. During cardiac catheterization, LV pressure was recorded with a high-fidelity catheter-tipped transducer. Baseline rhythms were sinus rhythm or VVI pacing. Sequential VDD pacing with variable AV intervals was performed at the right ventricular apex (RVA), right ventricular septum (RVS), right ventricular outflow tract (RVOT) and coronary sinus (CS). LV systolic function was assessed by calculating dP/dtmax and LV diastolic function was indexed by calculating the exponential isovolumic relaxation constant (Tau). Percentage changes (mean ± SE) from baseline to pacing were measured. Results: RVA pacing reduced dP/dtmax (-0.8 ± 8.4%) and prolonged Tau (7.0 ± 5.6%); RVS pacing enhanced dP/dtmax (20.7 ± 15.3%) and shortened Tau (-10.4 ± 9%); RVOT pacing reduced dP/dtmax (-8.0 ± 20.0%) and shortened Tau (-6.0 ± 12.2%); CS pacing reduced dP/dtmax (-11.7 ± 13.0%) and prolonged Tau (10.5 ± 11.9%). Our results demonstrated that different pacing sites have different effects on LV contractility and relaxation in patients with normal LV function. Conclusion: Since pacing at the RVS preferably increased LV dP/dtmax and shortened Tau, it may be a better alternative than the RVA.

Original languageEnglish
Pages (from-to)32-36
Number of pages5
JournalJournal of the Chinese Medical Association
Volume69
Issue number1
DOIs
StatePublished - Jan 2006

Keywords

  • Left ventricular function
  • Left ventricular relaxation
  • Pacing therapy

Fingerprint

Dive into the research topics of 'Acute effects of dual-chamber pacing on the left ventricular systolic function and relaxation in patients with advanced AV block and sick sinus syndrome'. Together they form a unique fingerprint.

Cite this