TY - JOUR
T1 - Atrial contraction and mitral annular dynamics during acute left atrial and ventricular ischemia in sheep
AU - Timek, Tomasz A.
AU - Lai, David T.
AU - Tibayan, Frederick
AU - Daughters, George T.
AU - Liang, David
AU - Dagum, Paul
AU - Lo, Sidney
AU - Craig Miller, D.
AU - Ingels, Neil B.
PY - 2002/11/1
Y1 - 2002/11/1
N2 - In six sheep, radiopaque markers were placed on the left ventricle (LV), the mitral annulus, the left atrium (LA), and the central edge of both mitral leaflets to investigate the effects of acute LV ischemia on atrial contraction, mitral annular area (MAA), and mitral regurgitation (MR). Animals were studied with biplane videofluoroscopy and transesophageal echocardiography before and during balloon occlusion of the left anterior descending (LAD), distal circumflex (dLCX), and proximal circumflex (pLCX) coronary arteries. MAA and LA area were calculated from the corresponding markers. LAD occlusion did not alter LA area reduction or presystolic MAA reduction, whereas dLCX occlusion resulted in a mild decrease in the former with no change in the latter. Neither occlusion resulted in MR. pLCX occlusion, however, significantly decreased LA area and presystolic MAA reduction and resulted in increased end-diastolic MAA, delayed valve closure from end diastole, and MR. Decreased atrial contractile function, as observed during acute posterolateral ischemia, is linked to diminished presystolic mitral annular reduction, a larger mitral annular size at end diastole, and MR.
AB - In six sheep, radiopaque markers were placed on the left ventricle (LV), the mitral annulus, the left atrium (LA), and the central edge of both mitral leaflets to investigate the effects of acute LV ischemia on atrial contraction, mitral annular area (MAA), and mitral regurgitation (MR). Animals were studied with biplane videofluoroscopy and transesophageal echocardiography before and during balloon occlusion of the left anterior descending (LAD), distal circumflex (dLCX), and proximal circumflex (pLCX) coronary arteries. MAA and LA area were calculated from the corresponding markers. LAD occlusion did not alter LA area reduction or presystolic MAA reduction, whereas dLCX occlusion resulted in a mild decrease in the former with no change in the latter. Neither occlusion resulted in MR. pLCX occlusion, however, significantly decreased LA area and presystolic MAA reduction and resulted in increased end-diastolic MAA, delayed valve closure from end diastole, and MR. Decreased atrial contractile function, as observed during acute posterolateral ischemia, is linked to diminished presystolic mitral annular reduction, a larger mitral annular size at end diastole, and MR.
KW - Left ventricular ischemia
KW - Mitral annulus
KW - Mitral regurgitation
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U2 - 10.1152/ajpheart.00149.2002
DO - 10.1152/ajpheart.00149.2002
M3 - Article
C2 - 12384471
AN - SCOPUS:0036838627
SN - 0363-6135
VL - 283
SP - H1929-H1935
JO - American Journal of Physiology - Heart and Circulatory Physiology
JF - American Journal of Physiology - Heart and Circulatory Physiology
IS - 5 52-5
ER -