Yoshikazu Tsuruhara

Analysis of determinants of ventricular fibrillation induced by reperfusion: Dissociation between electrical instability and myocardial damage

To assess the underlying mechanisms of ventricular fibrillation induced by myocardial reperfusion after cardioplegic arrest, 62 patients undergoing an open heart operation were divided into two groups based on the absence (group 1, n = 37) or the development (group 2, n = 25) of reperfusion-induced ventricular fibrillation. There was no close relationship between the incidence of reperfusion-induced ventricular fibrillation and aortic clamp time. On reperfusion, the time to onset of cardiac activity was similar in groups 1 (2.4 +/- 1.8 minutes) and 2 (1.9 +/- 1.1 minutes). At that time, there was no significant difference in values of arterial oxygen and bicarbonate contents, pH, or base excess between the two groups, but myocardial temperature was significantly higher in group 2 (25.6 degrees +/- 3.4 degrees versus 27.6 degrees +/- 2.4 degrees C; p less than 0.05). In addition, serum levels of sodium (123.9 +/- 4.2 versus 126.1 +/- 3.7 mmol/L; p less than 0.05) and calcium (0.80 +/- 0.07 versus 0.84 +/- 0.05 mmol/L; p less than 0.05) were significantly higher and serum potassium levels (3.98 +/- 0.58 versus 3.55 +/- 0.61 mmol/L; p less than 0.02) and the serum potassium to calcium ratio (4.94 +/- 0.90 versus 4.29 +/- 0.72; p less than 0.01) significantly lower in group 2. Postoperative serum levels of the myocardial-specific isoenzyme of creatine kinase and myoglobin were similar in both groups. By multivariate analysis, shorter ischemic time, higher myocardial temperature, higher serum sodium concentration, and lower serum potassium to calcium ratio were found to influence induction of reperfusion-induced ventricular fibrillation.(ABSTRACT TRUNCATED AT 250 WORDS)

Combined Method of Antegrade and Retrograde Cardioplegia in Double Valve Replacement.

大動脈弁と僧帽弁の二弁置換症例を対象に, 心筋保護液の順行性投与 (Ante) 法と逆行性投与 (Retro) 法の心筋保護効果を比較した. Ante 群15例, Retro 群 (Ante 法併用 Retro 法) 13例について, 術前および術中因子, 再灌流後CPK-MB値の推移, 術周期心筋梗塞の頻度, 術後血行動態を検討した. 術前因子は両群間に差を認めなかった. 大動脈遮断中の心筋保護液投与の間隔は Ante 群29.2±4.8分, Retro 群24.0±3.8分と Retro 群にて有意に (p<0.01) 短く, また大動脈遮断時間も Ante 群134±27分, Retro 群119±25分と Retro 群にて短い傾向を認めた. 再灌流6時間でのCPK-MB値はAnte 群120±80IU/l, Retro 群78±50IU/lと Retro 群にて少ない傾向を認めた. 術周期心筋梗塞の頻度と術後血行動態には両群間に差を認めなかった. 以上より弁膜症症例においても, Ante 法併用 Retro 法は Ante 法と同等以上の心筋保護効果を有し, 症例によっては推奨される有用な心筋保護法と考えられた.