Will a partial posterior annuloplasty ring prevent acute ischemic mitral regurgitation?

Tomasz A. Timek, Paul Dagum, David T. Lai, Frederick Tibayan, David Liang, George T. Daughters, Motoya Hayase, Neil B. Ingels, D. Craig Miller

    Research output: Contribution to journalArticle

    22 Scopus citations

    Abstract

    Background - Acute posterolateral ischemia in sheep results in ischemic mitral regurgitation (IMR). While complete ring annuloplasty prevents acute IMR, partial annuloplasty rings may offer a more physiologic repair, but are untested in animal models of IMR. Methods - Radiopaque markers were placed on the LV, mitral annulus (MA), and leaflets in 13 sheep. Seven sheep served as controls, and 6 had a St. Jude Tailor partial flexible ring implanted (29 mm in 5, 31 mm in 1). After 8±1 day, the animals were studied with biplane videofluoroscopy and echocardiography before and during acute posterolateral LV ischemia (balloon occlusion of circumflex artery). Mitral annular area (MAA), septal-lateral annular diameter (SL), annular perimeters, and leaflet edge separation were calculated from 3-D marker coordinates. Results - The average degree of mitral regurgitation increased from 0.0±0.0 to 2.1-0.7 (P=0.0006) in the control group during acute ischemia but remained unchanged in the Tailor group (0.1±0.2 for both conditions). The change in MAA throughout the cardiac cycle before ischemia was 17±4% in control animals, but only 5±2% (P=0.0002) in the Tailor ring group. Unlike the control animals, there was no increase in MAA (5.4±0.8 and 5.5±0.7 cm2, respectively; p=NS) nor dilatation of the muscular annulus (6.2±0.3 and 6.2±0.4, respectively; p=NS) during ischemia with the Tailor ring. Mitral SL dimension increased slightly with ischemia (2.3±0.2 versus 2.2±0.2 cm, P=0.03). Although posterior leaflet motion was limited, as observed with complete rings, normal annular flexion was maintained with the Tailor ring before and during acute ischemia. Conclusions - The Tailor partial annuloplasty ring prevented acute IMR probably by limiting SL diameter dilatation during acute ischemia. In this animal model of acute IMR, a partial, flexible posterior annuloplasty ring is as effective as a complete ring.

    Original languageEnglish (US)
    Pages (from-to)I33-I39
    JournalCirculation
    Volume106
    Issue number13 SUPPL.
    StatePublished - Sep 24 2002

      Fingerprint

    Keywords

    • Ischemia
    • Mitral valve
    • Regurgitation
    • Valvuloplasty

    ASJC Scopus subject areas

    • Cardiology and Cardiovascular Medicine
    • Physiology (medical)

    Cite this

    Timek, T. A., Dagum, P., Lai, D. T., Tibayan, F., Liang, D., Daughters, G. T., Hayase, M., Ingels, N. B., & Miller, D. C. (2002). Will a partial posterior annuloplasty ring prevent acute ischemic mitral regurgitation? Circulation, 106(13 SUPPL.), I33-I39.