造影剤が左室造影後の心機能に及ぼす影響—IohexolとDiatrizoateの比較

Effects of contrast media on left ventricular function.:Comparison with Iohexol and Diatrizoate

　〔目的〕左室造影における非イオン性低浸透圧造影剤（Iohexol：I群）の左室機能に及ぼす影響について従来のイオン性高浸透圧造影剤（Diatrizoate：D群）と比較検討し，その特性および有用性を明らかにすること。〔対象および方法〕対象は虚血性心疾患18例（1：8例，D：10例）で，カテ先マノメーターにて左室圧同時記録による左室造影を各造影剤（毎秒12ml計40ml）4分間隔で2回施行した。RAO 30°の左室像を1 frame（20msec）ごとにトレースして容積を算出し左室圧・容量曲線を作成した。〔結果〕①造影後の左室拡張末期圧，容量の増加はI群に比しD群で大であった（1：9ml,3mmHg増加，D：13ml，7mmHg増加）。②左室駆出率はD群で造影後増加したがI群では変化がなかった。③左室拡張期圧・容量曲線はI，D群ともに上方へ偏位したがI群でその程度は軽かった。〔結語〕IohexolはDiatrizoateと比較してその低浸透圧性によって左室拡張機能への影響は軽微であり，臨床上有用な造影剤と考えられた。

To investigate the effects of a low-osmolar non-ionic (Iohexol: I) and a high osmolar ionic contrast media (Diatrizoate: D) on left ventricular (LV) func-tion after left ventriculography (LVG), we studied 19 patients with coronary artery disease (I: 9 cases, D: 10 cases) during diagnostic cardiac catheterization. The first LVG was performed by injecting 40ml of I or D at a rate of 12ml/sec, measuring simultaneous LV pressure with a catheter tip manometer (Millar instruments). At 4 minutes after the first LVG, we repeated hemodynamic measurements and LVG. Si-ngle-plane volumes (RAO 30°) were calculated every 20msec (50 frame/sec) using the area-length method. LV systolic function was estimated by ejection frac-tion (EF), ratio of end-systolic pressure to end-systo-lic volume (ESP/ESV) and maximal (+) dP/dt LV relaxation was assessed by the time constant (T) of LV pressure decay. LV diastolic compliance was evaluated by the diastolic pressure-volume (PV) rela-tionship. Results. 1. LV end-diastolic pressure and volume were augmented more significantly in D than in I group, probably due to the difference of their osmolarity. 2. EF increased in D group with incr-ease of LV preload after the first LVG, but didn't change in I group. ESP/ESV and maximal (+) dP/dt were not changed after the first LVG in both groups. 3. LV isovolumic relaxation remained unchanged with I and D. 4. LV diastolic PV relation curve shifted upward more in D than I group. We con-clude that Iohexol has less influences on LV function than Diatrizoate and may be used in high risk pati-ents.