[Efficacy of coronary artery reconstruction in maintaining myocardial viability: quantitative determination of local myocardial circulation with 13NH3 myocardial positron emission tomography].
Thirty patients (280 areas) whose bypass grafts remained patent after surgical reconstruction of the coronary artery were examined. Before and after reconstruction, local myocardial blood circulation in infarcted regions and post-stenotic regions was measured by 13 NH(3) myocardial positron emission computed tomography (PET) at rest of during physical exercise in order to evaluate the efficacy of coronary artery reconstruction. Before operation, mean blood flow in post-stenotic regions (n = 198) was 65 +/- 15 ml/min/100 g at rest and 85 +/- 23 ml/min/100 g during exercise. After coronary artery bypass grafting (CABG), mean blood flow was increased to 78 +/ 21 ml/min/100 g at rest (p, 0.01) and 105 +/- 32 ml/min/100 g during exercise (p < 0.01). In infarcted regions (n = 82), mean blood flow before operation was 51 +/- 23 ml/min/100 g at rest and 69 +/- 23 ml/min/100 g during exercise. After CABG, it increased to 62 +/- 19 ml/min/100 g at rest (p < 0.01) and 81 +/- 29 ml/min/100 g during exercise (p < 0.01). Thus, significant increases in blood flow were observed in both post-stenotic and infarcted regions at rest and physical exercise after operation. The regions of infarction were divided into three groups based on local myocardial blood flow at rest before operation: Group I: greater than 45 ml/min/100 g (n = 35); Group II: less than 45 ml/min/100 g (n = 30) but greater than 30 ml/min/100 g; and Group III: less than 30 ml/min/100 g (n = 30). The efficacy of reconstruction was compared among these groups. The group with preoperative myocardial blood flow greater than 30 ml/min/100 g had increased blood flow after operation, indicating myocardial viability.
Kobayashi
S
S
Department of Surgery, Showa University School of Medicine, Tokyo, Japan.
Takaba
T
T
Kume
M
M
Kashima
T
T
Michihata
T
T
D000328:Adult; D000368:Aged; D001026:Coronary Artery Bypass; D003326:Coronary Circulation; D005260:Female; D006321:Heart / Q000000981:diagnostic imaging*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000473:pathology / Q000503:physiopathology / Q000601:surgery; D009206:Myocardium / Q000473:pathology*; D011184:Postoperative Period; D012501:Saphenous Vein / Q000637:transplantation; D013895:Thoracic Arteries / Q000637:transplantation; D014022:Tissue Survival; D014055:Tomography, Emission-Computed; D014654:Vascular Patency