[Assessment of abnormal left ventricular systolic blood flow in atrial fibrillation].
In atrial fibrillation, it is known that hemodynamics vary according to the preceding R-R intervals. However, the informations of blood flow dynamics have not been available because of the methodological limitations. In this study, blood flow dynamics of atrial fibrillation were assessed using pulsed Doppler echocardiography. The subjects were 160 consecutive patients with atrial fibrillation and without left ventricular asynergy. Using a commercially-available pulsed Doppler instrument (Aloka SSD-910), blood flow patterns in the left ventricle were investigated from the apical long-axis view. The results were as follows: 1. In 22 of the 160 cases (14%), systolic blood flow in the central or apical region of the left ventricle directed towards the apex (termed "back flow"). 2. In the cardiac cycle with "back flow", the preceding R-R interval was shorter; whereas it was longer when "back flow" was absent (591 +/- 103 vs 817 +/- 179 msec, p less than 0.01). Moreover, when a long R-R interval (PPI) followed by a short R-R interval (PI) was observed (greater PPI/PI ratios), the next beat showed distinct "back flow". 3. Left ventricular ejection fraction decreased significantly in patients with "back flow" compared to those without it (42 +/- 15 vs 66 +/- 12%, p less than 0.01). 4. On left ventriculography, the motion of the base of the heart was preserved; however, with "back flow", the motion of the apical area was abnormal, extending towards the apex along the longitudinal axis. 5. Left ventricular ejection flow at the outflow tract disappeared in 13 of the 22 cases with "back flow" in cardiac cycles with short preceding R-R intervals.(ABSTRACT TRUNCATED AT 250 WORDS)
Mawatari
K
K
Second Department of Internal Medicine, Kagoshima University School of Medicine.
Kuroiwa
N
N
Sanada
J
J
Kawahira
M
M
Kawagoe
H
H
Nakamura
K
K
Hashimoto
S
S
D001281:Atrial Fibrillation / Q000503:physiopathology*; D004452:Echocardiography / Q000379:methods; D006352:Heart Ventricles / Q000503:physiopathology; D006439:Hemodynamics; D006801:Humans; D009200:Myocardial Contraction; D013599:Systole