田中 康博, 真田 純一, 尾立 源晴, 徳留 昌幸, 馬渡 浩介, 中村 一彦, 有馬 證牙享

Yasuhiro TANAKA, Jun-ichi SANADA, Motoharu ODACHI, Masayuki TOKUDOME, Kousuke MAWATARI, Kazuhiko NAKAMURA, Terukatsu ARIMA

鹿児島大学医学部第二内科

The Second Department of Internal Medicine, Faculty of Medicine, University of Kagoshima

キーワード : Pulsed Doppler echocardiography, Isovolumic relaxation flow, Old myocardial infarction

We have previously reported that left ventricular blood flow in normal subjects during isovolumic relaxation period (isovolumic relaxation flow: IRF) is directed toward the apex from the center on pulsed Doppler echocardiography. In some patients with old myocardial infarction (OMI), IRF showed reversed flow from the center to the base. The purpose of this study is to determine the factors which affect the velocity of reversed IRF and to clarify its pathophysiological significance.
Out of 175 consecutive patients with OMI examined by cardiac catheterization, 30 patients had completely reversed IRF as shown by pulsed Doppler echocardiograpy. They were subdivided into two groups according to flow velocity: 13 patients with velocity not less than 20 cm/sec. (Group I), and 17 patients less than 20 cm/sec. (Group II).
The results were as follows: 1) All of these patients had apical wall motion abnormalities on left ventriculogram. 2) The percent abnormally contracting segments (%ACS) on left ventriculogram was significantly larger in Group I than in Group II (20±7% vs. 10±5%, PIn conclusion, reversed flow during relaxation period was shown in the limited patients with apical wall motion abnormalities. The velocity of this flow was affected by the size of the apical wall motion abnormality or by the relaxation at the basal site. In other words, reversed IRF with high velocity occurred when the wall motion abnormality was large and the basal remaining myocardium had good relaxation in patients with apical infarction. Determinating the velocity of reversed IRF is helpful in noninvasively predicting the size of wall motion abnormality noninvasively in patients with apical OMI.