Effect of long-term physical exercise of peripheral nerve: comparison of nerve conduction study and ultrasonography.

AIM: The aim of this study was to assess the effects of long-term physical exercise on peripheral nerve using both nerve conduction study (NCS) and ultrasonography (US). METHODS: The authors measured nerve conduction study and ultrasonography in 15 male (mean, 20±1.5 years) handball players and 13 male (mean, 21.3±1.9 years) control subjects. Cross-sectional area of the median nerve was evaluated using ultrasonography at the carpal tunnel and 6 cm proximal to the wrist, and the ulnar nerve at 6 cm proximal to the wrist crease, 2 cm proximal to the medial epicondyle, the epicondyle, and 2 cm distal to epicondyle. RESULTS: US shows significantly increased cross-sectional area of both median and ulnar nerve in the players compared with that in the controls, and the latency times in both nerves were significantly delayed in the players compared with that in the controls. Cross-sectional area of the median nerve showed a significant correlation with latency (r=0.330, P<0.01). CONCLUSION: This study suggests that the players have a tendency toward having both median and ulnar motor nerve damage in the wrist or elbow region although they are asymptomatic.

Association of elevated sulfatides and sulfotransferase activities with human renal cell carcinoma.

Lactosylceramide sulfate and galactosylceramide sulfate were found to increase markedly in human renal cell carcinoma (adenocarcinoma) as compared to uninvolved tissue. Activities of two sulfotransferases toward galactosylceramide and lactosylceramide as substrates were significantly elevated in the carcinoma compared to the uninvolved tissue resulting in enhanced synthesis of the two sulfatides in the carcinoma. The elevation of the two sulfotransferases was parallel in most tumors, suggesting that the same enzyme is responsible for the enhanced synthesis of two sulfatides. No consistent difference in the activity of arylsulfatase A, which desulfates the two sulfatides, was observed between the carcinoma and uninvolved tissue. Both the present and previous results show that the increased synthesis of the sulfatide(s) due to elevated sulfotransferase activity could be a biochemical characteristic common to adenocarcinomas derived from different tissues.

Prediction of acute left main coronary artery obstruction by 12-lead electrocardiography. ST segment elevation in lead aVR with less ST segment elevation in lead V(1).

OBJECTIVES: We sought to determine the electrocardiographic (ECG) features associated with acute left main coronary artery (LMCA) obstruction. BACKGROUND: Prediction of LMCA obstruction is important with regard to selecting the appropriate treatment strategy, because acute LMCA obstruction usually causes severe hemodynamic deterioration, resulting in a less favorable prognosis. METHODS: We studied the admission 12-lead ECGs in 16 consecutive patients with acute LMCA obstruction (LMCA group), 46 patients with acute left anterior descending coronary artery (LAD) obstruction (LAD group) and 24 patients with acute right coronary artery (RCA) obstruction (RCA group). RESULTS: Lead aVR ST segment elevation (>0.05 mV) occurred with a significantly higher incidence in the LMCA group (88% [14/16]) than in the LAD (43% [20/46]) or RCA (8% [2/24]) groups. Lead aVR ST segment elevation was significantly higher in the LMCA group (0.16 +/- 0.13 mV) than in the LAD group (0.04 +/- 0.10 mV). Lead V(1) ST segment elevation was lower in the LMCA group (0.00 +/- 0.21 mV) than in the LAD group (0.14 +/- 0.11 mV). The finding of lead aVR ST segment elevation greater than or equal to lead V(1) ST segment elevation distinguished the LMCA group from the LAD group, with 81% sensitivity, 80% specificity and 81% accuracy. A ST segment shift in lead aVR and the inferior leads distinguished the LMCA group from the RCA group. In acute LMCA obstruction, death occurred more frequently in patients with higher ST segment elevation in lead aVR than in those with less severe elevation. CONCLUSIONS: Lead aVR ST segment elevation with less ST segment elevation in lead V(1) is an important predictor of acute LMCA obstruction. In acute LMCA obstruction, lead aVR ST segment elevation also contributes to predicting a patient's clinical outcome.

Distinctive glycolipid patterns in Wilms' tumor and renal cell carcinoma.

Glycolipid patterns were analysed chromatographically in Wilms' tumor and renal cell carcinoma tissues and compared with those of uninvolved tissue. Ganglioside GM3 was found to be increased in both cancer tissues, whereas sulfatides accumulated only in renal cell carcinoma, as reported earlier. Neolactotetraosylceramide was detected in both cancer tissues, but not in the uninvolved kidney tissues. In four cases of Wilms' tumors, only a low level of sulfotransferase towards galactosylceramide was found in one case, while no activity was detected in the three other cases. Present results show that the increased sulfatide(s) in the renal cell carcinoma and the deficiency of the sulfatides in Wilms' tumors appear to be biochemical characteristics of histologically different carcinomas.

Coronary artery bypass surgery with arterial grafts in familial hypercholesterolemia.

OBJECTIVE: Familial hypercholesterolemia is a dominantly inherited disorder caused by mutations at the locus for the low-density lipoprotein receptor and is frequently associated with premature coronary artery disease. This study was performed to determine whether arterial grafting was associated with long-term benefits for patients with familial hypercholesterolemia. METHODS: During the past 18 years, 101 patients with heterozygous familial hypercholesterolemia underwent primary coronary artery bypass grafting, with one hospital death. Group 1 patients (n = 31) received only saphenous vein grafts. Group 2A patients (n = 47) received one internal thoracic artery graft and supplemental vein grafts, and group 2B patients (n = 23) had multiple arterial grafts. After operation, all patients received diet therapy and intensive cholesterol-lowering drug therapy. Thirteen patients received low-density lipoprotein apheresis. RESULTS: During a mean follow-up period of 95 months, 8 patients died, 9 underwent reoperation, and 12 received catheter intervention. The overall survival was 82% (95% confidence limits, 65%-97%) at 18 years after operation. The survival in group 2 was higher than that found in group 1 (P =.01). The overall freedom from major cardiac events (myocardial infarction, cardiac death, reoperation, and catheter intervention) was 57% (95% confidence limits, 40%-74%) at 16 years after operation. The freedom from reoperation in group 2 was higher than that found in group 1 (P =.03). There was no difference in the survival or freedom from major cardiac events between groups 2A and 2B. CONCLUSION: Arterial grafting improved the long-term freedom from reoperation in patients with familial hypercholesterolemia. Additional benefit of multiple arterial grafting could not be identified.

Coronary artery bypass grafting in familial hypercholesterolemia.

Familial hypercholesterolemia is an autosomal dominant disorder caused by a mutation of the gene for the low-density lipoprotein receptor and is characterized by rapidly progressing coronary atherosclerosis. We assessed the long-term results of coronary artery bypass grafting performed during the past 13 years in 62 patients with heterozygous familial hypercholesterolemia, whose mean plasma total and low-density lipoprotein cholesterol level was 327 mg/dl, respectively. The patients had severe coronary atherosclerosis, with coronary stenosis index of 19.7, and the prevalence of extracoronary atherosclerotic lesions was 27%. Sixty-one patients underwent successful coronary artery bypass operation, with an average of 2.5 grafts, and the coronary stenosis index decreased to 7.1. After operation, all patients consumed a cholesterol-lowering diet and received drug therapy with pravastatin, probucol, or cholestyramine. Seven patients who were resistant to drug therapy were treated with plasma low-density lipoprotein apheresis. The cholesterol-lowering therapy reduced plasma total cholesterol level by 37%, low-density lipoprotein cholesterol level by 42%, and low-density lipoprotein/high-density lipoprotein cholesterol ratio by 37% (p < 0.001). During the follow-up period (mean, 52 months; range, 10 to 157 months), there was no cardiac death, but three patients died of malignant disease. The actuarial survival rate was 95% at 5 years and 89% at 12 years after operation. The actuarial freedom from recurrent angina was 90% at 5 years and 53% at 11 years after operation. Four patients underwent reoperation, an average of 8 years postoperatively, because of vein graft atherosclerosis. In spite of severe coronary atherosclerosis, these patients with familial hypercholesterolemia showed good long-term outcome after coronary artery bypass operation. The present findings suggest that aggressive use of arterial grafts, intensive cholesterol-lowering drug therapy, and low-density lipoprotein apheresis may be useful in patients with familial hypercholesterolemia.

Is internal thoracic artery grafting suitable for a moderately stenotic coronary artery?

Grafting an internal thoracic artery to a coronary artery with moderate stenosis remains controversial. Competitive flow from the native coronary artery has been proposed as the cause of distal narrowing and ultimate failure of the internal thoracic artery graft. We investigated intraoperative phasic blood flow in internal thoracic arteries grafted to coronary arteries with various degrees of stenosis and the influence of stenosis on postoperative angiographic findings. One hundred patients who underwent coronary artery bypass grafting of an internal thoracic artery to the left anterior descending coronary artery were divided into three groups according to degree of coronary stenosis. Group 1 included 39 patients who had 75% or less stenosis, group 2 included 34 patients with stenosis from 76% to 90%, and group 3 included 27 patients with stenosis greater than 90%. Mean flow and peak systolic flow of internal thoracic artery graft in group 1 were lower than those in group 2 (p < 0.01, p < 0.05). Peak diastolic flow in group 1 showed no difference from flows in groups 2 and 3. In eight patients in group 1, internal thoracic artery flow showed a predominant diastolic peak with characteristic systolic reversal as a result of competitive flow from the native coronary artery. Angiography at 1 month showed that the internal thoracic artery graft was patent in every case. Relative contributions of native coronary artery and internal thoracic artery flow to distal perfusion differed among the three groups (p < 0.001). In group 1, 15% of patients showed native-dominant flow, 62% showed balanced flow, and 23% showed internal thoracic artery-dependent flow. In group 2, 9% of patients showed native-dominant flow, 29% showed balanced flow, and 62% showed internal thoracic artery-dependent flow. In group 3, 96% of patients showed internal thoracic artery-dependent flow. String sign of the internal thoracic artery graft developed in only three patients; in two of these patients internal thoracic arteries were grafted to coronary arteries with stenosis of 50% or less and in the other patient there was competitive flow from a diagonal vein graft. Eleven of 13 internal thoracic arteries grafted to coronary arteries with stenosis of 50% or less did not show string sign. Competitive flow from a moderately stenotic coronary artery did not predispose the patient toward string sign of the internal thoracic artery graft in the presence of substantial diastolic internal thoracic artery flow. We conclude that internal thoracic artery grafting is acceptable for a moderately stenotic coronary artery.

Effects of bilateral transvenous diaphragm pacing on hemodynamic function in patients after cardiac operations. Experimental and clinical study.

The effects of bilateral transvenous diaphragm pacing and intermittent positive-pressure ventilation on hemodynamic function were compared by animal experiment in 18 dogs and by clinical study in 14 patients during the postoperative period after cardiac operations. Aortic, pulmonary arterial, right atrial, and left atrial pressures (transmural) and aortic flow were increased by diaphragm pacing in the canine experiment. In dogs with induced tricuspid insufficiency, aortic pressure, right and left atrial pressures, and aortic blood flow increased, similar to the results obtained in the clinical study. Diaphragm pacing produced a sufficient tidal volume (7.2 to 12 ml/kg) for maintenance of normal blood gas levels in the patients, all of whom recovered spontaneous breathing without any weaning problems after 2 to 6 hours of diaphragm pacing. The catheter electrode used for stimulation was placed 30 mm away from the sinus node to avoid arrhythmias. Respiratory control by diaphragm pacing is hemodynamically superior to that by intermittent positive-pressure ventilation, and its efficacy is expected, especially in critical cases or in diseases or conditions in which the decrease in the load of the right heart affects the hemodynamic status of the patient.

Elevated plasma superoxide dismutase activity in patients with systemic sclerosis.

Injury to vessel walls, especially microvascular damage due to free radicals, has been a focus of interest concerning the pathogenesis of systemic sclerosis. Excess reactive oxygen species may induce antioxidant defenses. We therefore measured plasma superoxide dismutase (SOD) activity in patients with systemic sclerosis and found average SOD activity of plasma in 16 patients with systemic sclerosis (5.00 +/- 3.10 U/ml) to be significantly (P < 0.001) higher than those in 89 healthy volunteers (1.56 +/- 0.234 U/ml). Patients with Raynaud's phenomenon and/or skin sclerosis had particularly high SOD activity. These findings suggest that plasma SOD activity may serve as a useful parameter for assessment of sclerotic progression and the presence of Raynaud's phenomenon.

A preliminary report of the treatment of blue nevus with dermal injection of riboflavin and exposure to near-ultraviolet/visible radiation (ribophototherapy).

Dye lasers are useful for treating pigmented skin lesions, but their equipment is expensive and bulky. A simple and cheap phototherapy would be acceptable to dermatologists for treating pigmented skin lesions such as nevus of Ota. We investigated as a pilot study whether dermal injection of riboflavin and exposure to near-ultraviolet/visible radiation (ribophototherapy) decreases the dermal pigment of blue nevi which are recalcitrant to laser therapy. The therapeutic efficacy was assessed by comparison of the amount of dermal pigment in hematoxylin-eosin specimens taken before and after treatment. Pigmentation of the nevus became faint to the depth of 1 mm with little noticeable epidermal change after 21 treatments. At the deeper dermis somewhere between 3 and 4 mm from the epidermis, ballooning degeneration of the dermal cells was observed in hematoxylin-eosin specimens. Ribophototherapy is hopeful for treating pigmented skin lesions.

Coronary artery bypass grafting in a patient with antiphospholipid syndrome.

We report a 32-year-old female patient with antiphospholipid syndrome including severe coronary artery disease and multiple arterial and venous thrombosis. The patient had occlusion of the right internal thoracic artery, diffuse stenosis of the left internal thoracic artery, and occlusion of the left saphenous vein. The patient underwent successful coronary artery bypass grafting using the right gastroepiploic artery and a segment of the right saphenous vein. Antiphospholipid syndrome should be considered in young patients with myocardial infarction.

Coronary steal caused by a right gastroepiploic artery graft.

We report a patient with coronary artery steal after gastroepiploic artery grafting to the right coronary artery. The coronary artery steal syndrome involves reversed flow in the gastroepiploic artery, which siphons blood from the heart and results in myocardial ischemia.

Occlusion of the left coronary ostium due to fusion of the aortic cusp to the wall.

We report on a patient with occlusion of the left coronary ostium and aortic regurgitation due to fusion of the left aortic cusp to the aortic wall. The left coronary flow was restored by excision of the adherent left aortic cusp and aortic valve replacement.

Therapeutic angiogenesis with intramyocardial administration of basic fibroblast growth factor.

BACKGROUND: Basic fibroblast growth factor (bFGF) induces endothelial cell and smooth muscle cell proliferation and stimulates angiogenesis. This study was designed to evaluate the effects of intramyocardial administration of bFGF on myocardial blood flow, angiogenesis, and ventricular function in a canine acute infarction model. METHODS: Myocardial infarction was induced in 12 dogs by ligation of the left anterior descending coronary artery. Within 5 minutes after coronary occlusion, 100 microg of human recombinant bFGF in 1 mL of saline was injected into the infarct and border zone in 6 dogs, whereas saline alone was used in 6 control dogs. Myocardial blood flow was determined with colored microspheres before and immediately after coronary ligation and again 3, 7, 14, and 28 days after treatment and it was expressed as percent of normal. Angiogenesis was evaluated by immunohistochemical studies 28 days later. Cardiac function was evaluated by repeated echocardiographic measurement. RESULTS: Treatment with bFGF significantly increased the endocardial blood flow in the border zone (7 days after infarction, 75%+/-7% and 41% +/-7% in the bFGF and control groups, respectively, p<0.01) as well as epicardial blood flow in the infarcted zone. Treatment with bFGF significantly increased the capillary density (39.7+/-2.3 and 22.7+/-1.1 vessels per visual field in the bFGF and control groups, respectively, p<0.01) as well as arteriolar density in the border zone. Treatment with bFGF significantly reduced the change in ratio of thickness of the infarcted wall to the normal wall (44%+/-6% and 26% +/-5% in the bFGF and control groups, respectively, p<0.05). It improved the left ventricular ejection fraction (7 days after infarction, 0.54+/-0.02 and 0.37+/-0.03 in the bFGF and control groups, respectively, p<0.01). CONCLUSIONS: Intramyocardial administration of bFGF increased the regional myocardial blood flow, reduced thinning of the infarcted region, and improved ventricular function in acute myocardial infarction. Intramyocardial administration of bFGF may be a new therapeutic approach for patients with acute myocardial infarction.

Myocardial oxygenation during terminal warm blood cardioplegia.

BACKGROUND: Terminal warm blood cardioplegia accelerates myocardial metabolic recovery. The process of myocardial oxygenation during terminal warm blood cardioplegia and its optimal administration are not clear. METHODS: We measured the myocardial tissue oxygen saturation (SO2) during reperfusion using near-infrared spectroscopy. Twenty-four dogs underwent 1 hour of ischemic arrest with cold crystalloid cardioplegia. They were then divided into four equal groups. Group 1 dogs received normal blood reperfusion. The other dogs received 15 mL/kg of terminal warm blood cardioplegia at 80 mm Hg in group 2 or at 60 mm Hg in group 3, and 30 mL/kg of cardioplegia at 60 mm Hg in group 4, followed by blood reperfusion. RESULTS: In group 1, the SO2 increased gradually during the early reperfusion and decreased transiently during the late reperfusion. In group 2, the SO2 increased rapidly but it decreased transiently during blood reperfusion. In groups 3 and 4, the SO2 increased rapidly and remained at high levels during the blood reperfusion. Reperfusion ventricular fibrillation occurred along with a SO2 decrease only in groups 1 and 2. The postischemic troponin-T levels of groups 3 and 4 were lower than that of group 1. The functional recovery in group 4 was better than those in the other three groups. CONCLUSIONS: Terminal warm blood cardioplegia accelerates the early SO2 increase and abolishes the SO2 decrease during subsequent reperfusion and reduces the incidence of reperfusion arrhythmia, suggesting that it ameliorates reperfusion injury and consequently improves postischemic functional recovery.

Internal thoracic artery graft function during exercise assessed by transthoracic Doppler echography.

BACKGROUND: Noninvasive quantitative assessment of internal thoracic artery (ITA) graft function at rest and during exercise is important in patients who have undergone coronary artery bypass grafting. METHODS: Blood flow in the ITA graft was measured using transthoracic color Doppler echography before and after operation in 50 patients who underwent coronary artery grafting using an ITA to the left anterior descending artery. The patients were divided into three groups according to the degree of coronary stenosis and previous anterior myocardial infarction: Group 1 included 12 patients with severe (90% or more) coronary stenosis accompanied by anterior infarction. Group 2 included 26 patients with severe coronary stenosis without anterior infarction. Group 3 included 12 patients with moderate (75% or less) coronary stenosis without anterior infarction. Transthoracic echographic images of the ITA were obtained through the first intercostal space using a 7.5-MHz probe, and the diameter and cross-sectional area of the ITA were measured on B-mode imaging. Systolic, diastolic, and mean blood flow velocity and volume were measured by the Doppler method. RESULTS: Internal thoracic artery diameter increased significantly from 2.2 mm to 2.4 mm after operation. The ITA flow patterns in both flow velocity and volume changed from systolic-dominant to diastolic-dominant after operation. Postoperative ITA graft flow was 82 +/- 24 mL/min, 53 +/- 30 mL/min, and 31 +/- 15 mL/min (p < 0.01, group 1 versus 3; p < 0.05, group 1 versus 2) and percent diastolic fraction of ITA flow was 72%, 68%, and 62% (not significant) in groups 1, 2, and 3, respectively. Compared with intraoperative ITA flow, which was measured using an ultrasound transit-time flowmeter, postoperative ITA graft flow was increased in group 1, but not changed in group 2 or 3. The ITA graft flow was measured before and after exercise in 19 patients and was compared with ITA flow in 10 normal control subjects. The ITA graft flow increased significantly with exercise in all patients in the three groups. Percent diastolic fraction of ITA flow increased significantly with exercise in patients with severe coronary stenosis (groups 1 and 2), but decreased significantly in patients with moderate stenosis (group 3). CONCLUSIONS: Changes in native coronary artery and ITA graft may be predicted by assessing ITA flow pattern during exercise. Transthoracic color Doppler echography is a clinically useful noninvasive method of assessing ITA graft function at rest and during exercise.

Coronary bypass flow during use of intraaortic balloon pumping and left ventricular assist device.

BACKGROUND: Intraaortic balloon pumping (IABP) and left ventricular assist device (LVAD) are used for left ventricular support when low cardiac output occurs after a coronary bypass operation for serious coronary artery disease. There are hemodynamic differences in blood flow in various kinds of coronary artery bypass grafts, caused by their inherent physiologic characteristics. The hemodynamic effects of left ventricular assistance with IABP and LVAD on blood flow through various coronary artery bypass grafts were investigated. METHODS: An ascending aorta-coronary bypass graft (ACB), an internal thoracic artery, and a descending aorta-coronary bypass graft were anastomosed to the left anterior descending coronary artery in a canine model. In this experimental model, the blood flow to the same coronary bed in the three types of grafts could be evaluated. Blood flow in the left anterior descending coronary artery through the three types of coronary bypass grafts was studied in this model during or in the absence of ventricular assistance. RESULTS: In the control study, the systolic blood flow did not differ among the three types of grafts, but the diastolic flow decreased in the following order: with the ACB, the internal thoracic artery, and the descending aorta-coronary bypass graft. The systolic flow during IABP and LVAD was similar to the control flows. Use of IABP increased the diastolic flow by 75.3%+/-12.4% of the control value in the ACB, 37.9%+/-25.0% in the internal thoracic artery, and 21.2%+/-11.4% in the descending aorta-coronary bypass graft. The LVAD increased the diastolic flow by 97.7%+/-18.7% of the control value in the ACB, 64.5%+/-25.7% in the internal thoracic artery, and 63.0%+/-27.9% in the descending aorta-coronary bypass graft. The diastolic blood flows in the left anterior descending coronary artery and the three types of grafts were significantly greater with IABP than the control values, and significantly greater with LVAD than with IABP and the control values. The degrees of increase of diastolic flows in the left anterior descending coronary artery and the ACB with IABP and LVAD were significantly greater than in the arterial grafts (p < 0.01). CONCLUSIONS: The diastolic flows in the internal thoracic artery and descending aorta-coronary bypass graft increased less than in the native left anterior descending coronary artery and ACB during left ventricular assistance, particularly with IABP. It is important for the selection of tactics for the management of catastrophic status after coronary bypass grafting to consider the hemodynamic characteristics of the graft.

Effect of low-dose aprotinin on coagulation and fibrinolysis in cardiopulmonary bypass.

To study the effect of low-dose aprotinin on hemostasis in patients undergoing cardiopulmonary bypass (CPB) for coronary artery bypass operations and to elucidate the mechanism of aprotinin action, we randomized 14 of 27 patients to receive 30,000 KIU/kg aprotinin in the CPB priming volume and 7,500 KIU/kg aprotinin intravenously each hour during CPB (1 patient was excluded from the aprotinin group because of protamine shock). Intraoperative and postoperative blood loss was significantly reduced in the aprotinin group. Antithrombin III level was significantly decreased, and the levels of thrombin-antithrombin III complexes were significantly increased during CPB in both groups, indicating activation of the clotting system. The marked increase in fibrin(ogen) degradation products during CPB in the control group, indicating enhanced fibrinolytic activity, was significantly reduced in the aprotinin group. alpha 2-Plasmin inhibitor was significantly reduced during CPB in the control group. The marked increase in alpha 2-plasmin inhibitor-plasmin complexes in the control group, indicating plasmin activity, was significantly reduced in the aprotinin group. A marked decrease in the platelet count was observed during CPB similarly in both groups. These findings demonstrated that low-dose aprotinin administration was effective in reducing intraoperative and postoperative blood loss and that activation of the clotting system during CPB was not followed by hyperfibrinolysis in aprotinin-treated patients. The improved hemostasis is mainly attributable to the prevention of hyperfibrinolysis during CPB.

Physiologic characteristics of coronary artery bypass grafts.

To investigate the hemodynamic characteristics of arterial grafts for coronary artery bypass grafting, we measured phasic pressure and flow patterns in three types of grafts in a canine model (n = 18). A graft from the ascending aorta (AAG), a graft from the descending aorta at the first lumbar level (DAG), analogous to a right gastroepiploic artery, and an internal thoracic artery (ITA) were anastomosed to each other. The composite graft was anastomosed to the left anterior descending coronary artery, and then the left anterior descending coronary artery was ligated. Before grafting, the AAG showed high sustained diastolic pressure, but the ITA and DAG showed rapid fall of diastolic pressures. Mean diastolic pressures were 83 +/- 2, 72 +/- 3, and 57 +/- 2 mm Hg in the AAG, ITA, and DAG (p < 0.05). Free flow in the AAG was markedly greater than in the ITA or the DAG. After grafting to the left anterior descending coronary artery, no changes were observed in diastolic pressures compared with the pregrafting values. Total blood flows were 72 +/- 6, 80 +/- 7, 57 +/- 7, and 44 +/- 6 mL/min in the left anterior descending coronary artery, AAG, ITA, and DAG, respectively. There were no differences in systolic graft flow between the three types of grafts. Diastolic blood flow in the ITA (29 +/- 4 mL/min) and DAG (18 +/- 3 mL/min) was smaller than in the AAG (48 +/- 4 mL/min) (p < 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)

Flow capacities of arterial grafts for coronary artery bypass grafting.

The flow capacities of arterial and saphenous vein grafts in 100 patients who had coronary artery bypass grafting were compared under exercise conditions by continuous ventricular function monitoring, which records serial beat-to-beat radionuclide data and calculates left ventricular ejection fractions every 20 seconds. Ejection fraction profiles during graded bicycle exercise were divided into four types. In type A, the ejection fraction continued to increase. In type B, the ejection fraction initially increased, but decreased during the late exercise stage. In type C, the ejection fraction did not change. In type D, the ejection fraction continued to decrease throughout exercise. A decrease in ejection fraction, observed in type B or D, is an early indicator of myocardial ischemia. Before operation, 10 patients showed type A, 30 type B, 11 type C, and 49 type D responses. After operation, 68 patients showed type A, 21 type B, and 11 type C responses. Patients were divided into three groups according the type of bypass graft. Group 1 included 21 patients with two arterial grafts and vein grafts; group 2, 61 patients with an internal thoracic artery graft and vein grafts; group 3, 18 patients with only vein grafts. All of the grafts were patent on angiography. Eight patients (38%) in group 1 and 13 (21%) in group 2 showed a postoperative type B response, but none of the patients in group 3 had a postoperative type B response (p < 0.02). Seven of 8 patients in group 1 with postoperative type B responses had only arterial grafts to the left-side coronary arteries.(ABSTRACT TRUNCATED AT 250 WORDS)