These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


Pubmed for Handhelds

PUBMED FOR HANDHELDS

Search MEDLINE/PubMed

  • Title: Biventricular pacing attenuates T-wave alternans and T-wave amplitude compared to other pacing modes.
    Author: Anh D, Srivatsa U, Bui HM, Vasconcellos S, Narayan SM.
    Journal: Pacing Clin Electrophysiol; 2008 Jun; 31(6):714-21. PubMed ID: 18507544.
    Abstract:
    BACKGROUND: The impact of altered ventricular activation, including biventricular (BV) pacing, on T-wave alternans (TWA) and arrhythmic substrates is unclear. We studied how differing ventricular activation sequence alters TWA; the interval from peak-to-end of the T-wave (TpTe) and T-wave amplitude during right (RV), left (LV), and biventricular (BV) pacing; and right atrial (RA) pacing in patients with preexisting conduction delay. METHODS AND RESULTS: We measured TWA during RA, RV, LV, and BV pacing in 33 patients receiving cardiac-resynchronization-therapy-defibrillators. TWA magnitude (V(alt)) was lower during BV than RV (P < 0.01), RA (P < 0.01), or LV pacing. As a result, BV-TWA was more often negative than RV-TWA (P < 0.01), LV-TWA, and RA-TWA, particularly when discordant between pacing modes (P < 0.01). Overall, 83% of TWA recordings were abnormal (25% indeterminate), and 17% negative. BV pacing reduced T-wave amplitude (P < 0.05) and TpTe (P < 0.005) compared to RV pacing and LV pacing (P < 0.05; P < 0.005 respectively). Notably, TWA magnitude varied linearly with T-wave amplitude for all pacing modes (P < 0.001). Over 410 +/- 252 days' follow-up, RV-TWA predicted the combined endpoint of death and ICD therapy with 86% negative predictive value (P < 0.05). BV-TWA, RA-TWA, and other repolarization indices were not predictive. CONCLUSIONS: BV pacing attenuates TWA in tandem with reduced T-wave magnitude. In these patients with baseline QRS prolongation, RV-TWA predicted events more effectively than BV-TWA and RA-TWA. Further studies are required to understand how altered ventricular activation influences repolarization dynamics and arrhythmic tendency.
    [Abstract] [Full Text] [Related] [New Search]