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Familial hypercholesterolemia is characterized by a high plasma level of cholesterol and is frequently associated with rapidly progressing coronary heart disease. The internal thoracic artery is recognized as the conduit of choice for coronary artery bypass grafting. This study was performed to determine whether multiple arterial grafting was associated or not with additional benefits for patients with familial hypercholesterolemia. Between June 1980 and March 1998, 95 patients with familial hypercholesterolemia. underwent a total of 103 coronary artery bypass procedures with one hospital death. The patients were divided into 3 groups according to the type of bypass graft. Group 1 included 31 patients with only saphenous vein grafts; Group 2,48 patients with one arterial graft and supplemental vein grafts; and Group 3, 24 patients with multiple arterial grafts. The overall actuarial survival rate was 90.9% at 10 years and 81.8% at 18 years. The overall actuarial freedom from recurrent angina was 68.9% at 10 years and 55.8% at 16 years. The actuarial survival rate in group 2 was higher than that in Group 1 (p < 0.05). There was no difference in the actuarial survival or in the freedom from cardiac events between Group 2 and Group 3. Single arterial grafting improved the long-term survival in patients with familial hypercholesterolemia. However, no additional benefit from multiple arterial grafting was identified.

Left ventricular function was compared in 14 patients who underwent mitral valve replacement with preservation of the posterior leaflet, chordae tendineae and papillary muscle (preserved group) and 14 patients who underwent conventional mitral valve replacement (non-preserved group). 99mTc radionuclide ventriculography was performed before surgery and one month after surgery. The early diastolic filling rate, an indicator of the efficiency of diastolic function, was measured. The patients in the non-preserved group showed an anteroseptal ejection fraction of 28 +/- 10% before surgery and 32 +/- 10% after surgery, an apical ejection fraction (71 +/- 10% vs 73 +/- 16%), and an inferolateral ejection fraction (56 +/- 16% vs 53 +/- 16%). The global ejection fraction tended to decrease from 56 +/- 9% to 52 +/- 10%. The patients in the preserved group showed an anteroseptal ejection fraction of 37 +/- 13% before surgery and 43 +/- 19% after surgery, an apical ejection fraction (74 +/- 20% vs 77 +/- 17%) and an inferolateral ejection fraction (53 +/- 11% vs 68 +/- 16%). The global ejection fraction, reflecting improvement in the inferolateral ejection fraction, tended to increase from 53 +/- 11% to 58 +/- 11%. The early diastolic filling rate for the preserved group was 1.73 +/- 0.43 before surgery and 1.05 +/- 0.61 after surgery, while that for the nonpreserved group was 1.59 +/- 0.24 vs 0.97 +/- 0.48. Although the early diastolic filling rate normalized in both groups, there was no significant difference between the two groups.(ABSTRACT TRUNCATED AT 250 WORDS)

The hemodynamics of blood flow in internal thoracic artery (ITA) grafts were studied using transthoracic duplex imaging prior to and following coronary artery bypass grafting (CABG) in 37 patients. Transthoracic images of the ITA were obtained through the first intercostal space using a 7.5 MHz probe, and their diameter and area were measured by B-mode imaging. Systolic, diastolic, mean and end-diastolic blood flow velocity (Vs, Vd, Vm, and Ved) were determined based on Doppler signals and systolic, diastolic, and total blood flow (Fs, Fd, and Ftotal) were calculated by the following formula: Flow = Vm x area x 60/10(3). The diameter of the ITA increased following CABG. Prior to CABG, Vs, and Fs, were dominant, while following CABG, the hemodynamic pattern was diastolic dominant, although individual variation existed. The ITA blood flow was measured in 4 groups, in patients who had had a previous anterior myocardial infarction and no redistribution on myocardial scintigraphy (group I), in patients with 99-100% coronary artery stenosis who had not had an anterior myocardial infarction or who had an anterior myocardial infarction and had redistribution (group IIa), in patients with the same criteria as group IIa but who had 90% coronary stenosis (group IIb), and in patients with 75% coronary stenosis who had not had anterior myocardial infarction (group IIc). Blood flow was 57, 73, 44mL and 34 mL/min, and the percentage of diastolic flow was 72, 69, 61, 59% respectively. These results show that ITA blood flow competes with native coronary artery flow in patients with moderate coronary stenosis.(ABSTRACT TRUNCATED AT 250 WORDS)

High-dose aprotinin has been reported to reduce blood loss after extracorporeal circulation (ECC). However, the hemostatic mechanism of aprotinin remains unknown. We administered aprotinin to 25 patients during coronary artery bypass surgery and examined the blood loss in comparison with that in a control group of 25 patients. On the basis of an experimental study on the effects of aprotinin, 30,000 KIU/kg of aprotinin was infused as the initial ECC dose and 7,500 KIU/kg/h was continuously administered as the maintenance dose from the beginning to the end of ECC. Aprotinin was not used before ECC. Serial blood samples were collected during and after the operation in both groups to examine various coagulation and fibrinolysis system parameters. Blood loss during and 6 hours after the operation and the total blood requirement were significantly lower in the aprotinin group than in the control. There was no difference between the two groups in terms of hemoglobin, platelet count, ACT, and thrombin-antithrombin III complex level. The aprotinin group showed a significantly higher level of alpha 2 (total) plasmin inhibitor and a significantly lower level of plasmin-alpha 2 plasmin inhibitor complex and D-dimer during ECC. These findings indicated that although the coagulation system function was accelerated during ECC, the fibrinolysis function system was suppressed by the administration of aprotinin, which resulted in a reduction of blood loss.

Patients with hypopituitarism are prone to perioperative complications resulting from adrenal insufficiency or hypothyroidism. Coronary artery bypass grafting was performed safely in a 53-year-old woman with postinfarction unstable angina and hypopituitarism. Cortisol and thyroid hormone were administered to maintain normal adrenal and thyroid function during and after the operation. Hydrocortisone was administered intravenously the day before surgery and for 2 weeks postoperatively and then was administered orally. Perioperative replacement thyroxine therapy was administered to avoid acute myocardial ischemia. Optimal thyroid replacement was achieved after surgery. No perioperative complications were seen. The patient remains free of angina with postoperative cortisol and thyroid hormone replacement therapy.

Coronary artery bypass grafting (CABG) was performed in 48 patients with heterozygous familial hypercholesterolemia (FH). Seventy-nine percent of these patients had three-vessel disease or left main trunk disease. The internal thoracic artery was used for grafting in 26 patients and the right gastroepiploic artery was used in 4 patients. Although no patient died during surgery, one died subsequently from graft-versus-host disease. Graft patency at one month after CABG was 95% in vein grafts, 100% in arterial grafts, and 97% overall. Histological study revealed that arterial grafts in patients with FH had similar structures to those in non-FH patients, without evidence of atherosclerosis. All patients were prescribed anti-cholesterol drugs to control serum cholesterol levels, and 4 patients underwent LDL-apheresis because of poor control. Survival rate at 11 years after CABG was 83% without cardiac death. Cardiac event-free rate in 47 surviving patients was 53% at 10 years after CABG in vein bypass group, 93% at 5 years in the arterial graft group, and 58% at 10 years overall. Results of CABG were as good in FH as in non-FH patients, using arterial grafts and anticholesterol therapy.

Binovular twins with congenital supravalvular aortic stenosis underwent Doty's extended aortoplasty. Neither twins displayed signs of Williams syndrome. Peak systolic pressure gradients of 65 and 70 mmHg, respectively, were measured across the stenotic portion at the ascending aortae. After surgery, the pressure gradients were reduced to 15 and 20 mmHg, respectively, at the aortic valves. No new aortic regurgitation was observed postoperatively. It is important that the ascending aorta, including the stenotic part, is symmetrically incised into the noncoronary and the right coronary sinus of Valsalva. The fibrous ring should be removed as completely as possible. Doty's extended aortoplasty is a safe and effective procedure for supravalvular aortic stenosis.

The early diagnosis of intraoperative myocardial ischemia is important because such ischemia can lead to myocardial infarction. Clinical effectiveness of transesophageal echocardiography (TEE) was evaluated for detecting intraoperative myocardial ischemia and for observing the recovery of cardial motion at the end of cardiopulmonary bypass (CPB) in 20 patients who had undergone CABG. After endotracheal intubation, the TEE transducer was introduced into the esophagus to obtain a short axis cross-sectional view of the left ventricle at the level of the papillary muscles. Global LV function was assessed by measuring end-diastolic and end-systolic areas, which were calculated automatically, and the fractional area change (FAC). Regional endocardial wall motion was also analyzed by subdivision into four anatomical segments. The mean FACs were 48% after intubation, 47% after skin incision and 48% after sternotomy. Thereafter it increased significantly to 59% 30 minutes after CPB and 56% at the end of the operation. Thus, global LV function was improved significantly by revascularization. TEE could detect myocardial ischemia more sensitively than ECG. In 9 patients, FAC decreased significantly and new regional wall motion abnormality (RWMA) appeared around the time of sternotomy, but no ECG changes were detected. In another 7 patients, new RWMAs were detected without either a decrease in the FAC or ECG changes. It was found that myocardial ischemia took place more frequently before the initiation of CPB than expected. The recovery of left ventricular wall motion from cardioplegic arrest was able to be monitored visually during the period of weaning from CPB and the TEE could facilitated prompt and exact judgement of weaning from CPB.(ABSTRACT TRUNCATED AT 250 WORDS)

The response of left ventricular function during exercise and recovery after exercise was assessed in 52 patients with coronary artery bypass surgery by means of a radionuclide continuous ventricular function monitor. This system consists of 2 radionuclide detectors, recorder and a computer. After the equilibration of 20 mCi technetium 99m-labeled autologaous red blood cells into the intravascular space, the beat by beat radionuclide data were summed for 20-sec intervals to measure left ventricular ejection fraction (EF). Before surgery, the mean EF decreased with exercise from 51 +/- 9% to 45 +/- 11% (p less than 0.001). Cardiac response was divided into 4 types according to the profiles of the EFs during exercise. In 6 patients, EF continued to increase until maximal exercise (type A). In 10 patients, EF initially increased and then decreased in late exercise stages (type B). In 9 patients, EF did not change significantly during exercise (type C). In 27 patients, EF decreased throughout exercise (type D). After surgery, the mean EF increased with exercise from 53 +/- 10% to 60 +/- 13% (p less than 0.001). Thirty-five patients showed type A, 9 type B, 5 type C, and 3 type D. Two type D and 5 type B patients had occluded grafts or ungrafted coronary arteries. Four patients with complete revascularization including an internal thoracic artery and saphenous vein grafts showed type B. Three patients with extensive infarction and poor left ventricular function showed type C.(ABSTRACT TRUNCATED AT 250 WORDS)