Hisateru Nishizawa

Coronary artery bypass grafting in octogenarians

Preoperative profiles, postoperative complications, and the early and late results in 32 patients 80 yrs. of age and older (elderly group) who underwent coronary artery bypass grafting were compared with those in patients under 80 yrs. of age (control group). In the elderly group, the prevalence of patients with preoperative creatinine clearance (Ccr.) <50 l/day (34.4%), unstable angina pectoris (78.1%) and left main trunk disease (40.1%) was significantly higher than those in the control group. The incidences of arrhythmia and intensive care unit(ICU) syndrome were also significantly higher in the elderly group than in the control group, however, there was no death due to these complications. In the elderly group, one patient (3.1%) died in the hospital due to low cardiac output syndrome (LOS), while three patients (2.4%) of the control group died in the hospital. As for the long-term results, the 5-yr. survival rates for the elderly group and the control group were 82.6% and 85.2%, respectively, and the effectiveness of surgery was remarkable, with improved postoperative activity in 96.9% of the elderly group. These findings indicate that although the elderly patients have higher risks by undergoing surgery and have a disadvantage in the rate of postoperative complications, the postoperative improvement in activity and survival rate can be similar to those in the younger patients.

Reactivity of the Internal Thoracic Artery Graft to Drugs in Coronary Artery Bypass Grafting.

冠動脈バイパス術(CABG)において,われわれは左内胸動脈(LITA)採取時にphosphodiesterase III (PDE III)阻害剤をLITAへ直接注入し拡張させ,攣縮を予防することで血流量を増加させるよう,工夫している.今回,PDE III阻害剤とともに,塩酸パパベリン,硝酸イソソルビド(ISDN)を用い,LITAの薬剤反応性について比較検討した.CABG 42例を対象とし,各薬剤14例において薬剤投与前後のgraft free flow (GFF)と体血圧を計測し,血管抵抗(R)値を算出した.各薬剤でGFFIは有意に増加し,R値,体血圧は有意に低下した.いっぽう,各薬剤間の体血圧変化率に有意差はなく,PDE III阻害剤はほかの薬剤よりGFF変化率が有意に増加し,R値変化率が有意に低下した.この結果より,動脈グラフトの血流量増加にPDE III阻害剤はより有用であることが示唆された.