A quantitative study of postoperative luminal narrowing of the internal thoracic artery graft in coronary artery bypass surgery.

We used quantitative angiography to determine the postoperative diameter of the internal thoracic artery graft at the point close to the anastomosed site in 147 patients who received the graft for the left anterior descending coronary artery. We performed generalized multiple linear regression analysis (Type I quantification method) to assess the effects of the following factors on the internal thoracic artery graft diameter: age, gender, time of angiography, laterality of the internal thoracic artery used, presence of an undivided major side branch of the internal thoracic artery, presence of a saphenous vein graft having blood flow competition with an internal thoracic artery graft, presence of distal stenosis of the recipient left anterior descending coronary artery, severity of postoperative left anterior descending coronary artery stenosis, and presence of coronary risk factors. The standardized category scores for 25% left anterior descending coronary artery stenosis, 50% left anterior descending coronary artery stenosis, and presence of a saphenous vein graft having blood flow competition with an internal thoracic artery graft were -1.418, -0.767 and -0.622, respectively. Thus, the internal thoracic artery diameter was smaller in patients with well-preserved flow of the recipient coronary artery. The internal thoracic artery diameter had a particularly strong correlation with the degree of left anterior descending coronary artery stenosis (partial correlation coefficient: 0.670). The other factors seemed to have little or no correlation with the postoperative internal thoracic artery diameter. With the criterion that the internal thoracic artery diameter below 1.0 mm represents the "string sign" of internal thoracic artery graft, this phenomenon was observed in nine patients (6.1%). In all of these patients, left anterior descending coronary artery flow was well-preserved, and no ischemia was disclosed in the left anterior descending coronary artery-perfused area. These results indicate that internal thoracic artery grafts have flow adaptability responding to the flow demand of the recipient coronary artery and that the string sign of internal thoracic artery grafts is mainly an outcome of its physiologic characteristics.     

Initial United States clinical trial of robotically assisted endoscopic coronary artery bypass grafting

OBJECTIVES: With traditional instruments, endoscopic coronary artery bypass grafting has not been possible. This study was designed to determine the clinical feasibility of using a robotically assisted microsurgical system to create endoscopic coronary anastomoses. Methods And Results: Ten patients underwent endoscopic coronary artery bypass grafting of the left internal thoracic artery to the left anterior descending artery. Subxiphoid endoscopic ports (2 for instruments, 1 for a camera) were placed, and a robotic system was used to perform the left internal thoracic artery-left anterior descending artery bypass graft. Conventional techniques were used to perform the other grafts. Blood flow through the left internal thoracic artery graft was measured in the operating room and was adequate in 8 of 10 patients. The 2 inadequate grafts were revised successfully by hand. Six weeks after the operation, selective coronary angiography demonstrated a graft patency of 100% (8/8). There were no technical failures of the robotic system. The only postoperative complication was mediastinal hemorrhage in 1 patient. CONCLUSIONS: This pilot study demonstrates the feasibility of robotically assisted endoscopic coronary artery bypass grafting.     

Benefits accruing to grafting of the right internal thoracic artery to the left anterior descending artery in coronary artery bypass grafting.

OBJECTIVES: We have investigated the effects and outcome from grafting the right internal thoracic artery to the left anterior descending artery in coronary artery bypass grafting. METHODS: We analyzed the findings in 185 patients who underwent coronary artery bypass grafting involving right internal thoracic artery-left anterior descending artery bypass. The survival rate, cardiac events related to the right internal thoracic artery-left anterior descending artery graft, and graft patency were investigated. In cardiac catheterization, the production of nitric oxide from the endothelium of the internal thoracic artery was measured as the plasma nitrite and nitrate levels by the Griess reaction. The reactions to acetylcholine infusion (5 micrograms) in the right internal thoracic artery (n = 4) were compared to those in the left internal thoracic artery (n = 9) grafts. RESULTS: The hospital mortality rate was 0.5%. The actuarial survival rate at 11 years after operation was 98.81%. The rate of freedom from cardiac events at 11 years after operation was 92.08%. The rate of patency of the right internal thoracic artery-left anterior descending artery was 97.0% in 133 patients. Nitric oxide production was calculated as (total nitrite plus nitrate production in response to stimulation by acetylcholine-total nitrite plus nitrate level before acetylcholine load)/(total nitrite plus nitrate level before acetylcholine load). There was no significant difference in changes in plasma concentration in response to acetylcholine stimulation between the right internal thoracic artery-left anterior descending artery and left internal thoracic artery-left anterior descending artery groups (20 +/- 29% versus 5 +/- 10%). CONCLUSIONS: The right internal thoracic artery-left anterior descending artery grafts exhibited good patency and release of nitric oxide in response to acetylcholine loading, similar to left internal thoracic artery-left anterior descending artery grafts.     

Benefits accruing to grafting of the right internal thoracic artery to the left anterior descending artery in coronary artery bypass grafting

Objectives: We have investigated the effects and outcome from grafting the right internal thoracic artery to the left anterior descending artery in coronary artery bypass grafting.Methods: We analyzed the findings in 185 patients who underwent coronary artery bypass grafting involving right internal thoracic artery-left anterior descending artery bypass. The survival rate, cardiac events related to the right internal thoracic artery-left anterior descending artery graft, and graft patency were investigated. In cardiac catheterization, the production of nitric oxide from the endothelium of the internal thoracic artery was measured as the plasma nitrite and nitrate levels by the Griess reaction. The reactions to acetylcholine infusion (5 μg) in the right internal thoracic artery (n = 4) were compared to those in the left internal thoracic artery (n = 9) grafts.Results: The hospital mortality rate was 0.5%. The actuarial survival rate at 11 years after operation was 98.81%. The rate of freedom from cardiac events at 11 years after operation was 92.08%. The rate of patency of the right internal thoracic artery-left anterior descending artery was 97.0% in 133 patients. Nitric oxide production was calculated as (total nitrite plus nitrate production in response to stimulation by acetylcholine-total nitrite plus nitrate level before acetylcholine load) / (total nitrite plus nitrate level before acetylcholine load). There was no significant difference in changes in plasma concentration in response to acetylcholine stimulation between the right internal thoracic artery-left anterior descending artery and left internal thoracic artery-left anterior descending artery groups (20 ± 29% versus 5 ± 10%).Conclusions: The right internal thoracic artery-left anterior descending artery grafts exhibited good patency and release of nitric oxide in response to acetylcholine loading, similar to left internal thoracic artery-left anterior descending artery grafts.     

Effect of target stenosis and location on radial artery graft patency.

OBJECTIVE: The purpose of this study was to evaluate the effect of target vessel characteristics on radial artery patency when used as a composite T graft. METHODS: Between October 1993 and March 2001, 1022 patients underwent coronary bypass with the internal thoracic artery-radial artery composite T graft. Of these, angiography has been performed on 109 patients at a mean 27.1 months (range, 2-70 months) postoperatively for symptoms of ischemia. By means of Cox proportional hazard models, the relationships between anastomotic patency and target vessel location, proximal stenosis, target diameter, and quality were assessed. RESULTS: A total of 231 radial artery anastomoses were evaluated. The mean stenosis for patent anastomoses was 82% compared with 71% for occluded anastomoses (P <.001). Anastomotic patency for targets with moderate stenosis (< or = 70%) was worse than that for vessels with critical stenosis (> or = 90%; relative risk, 1.7; 95% confidence interval, 1.3-2.2; P <.001). Patency for targets of the right coronary artery was statistically inferior to that for targets of the left anterior descending artery (relative risk, 1.8; 95% confidence interval, 1.2-2.9; P =.01) and bordered on significance versus that for the circumflex artery distribution (relative risk, 1.6; 95% confidence interval, 1.0-2.8; P =.06). When directed toward critically stenosed targets of the left anterior descending or circumflex arteries, radial artery patency was not statistically different that that of the internal thoracic artery (P =.19). CONCLUSION: Radial artery patency is sensitive to both target location and proximal target stenosis. Selective use of the radial artery to targets of the left anterior descending and circumflex distributions remains encouraging. Radial artery grafts to targets of the right coronary artery or those with moderate stenosis appear to be at particularly high risk of failure.     

Ulnar artery graft for myocardial revascularization.

We present a 60-year-old man who underwent coronary artery bypass grafting using an ulnar artery as one of the grafts intended to release angina pectoris. Previously, his right leg had been amputated following a traffic accident. The blood supply of his left leg was reduced due to atherosclerotic stenotic change (left ankle pressure index 0.6). He had been under treatment for severe diabetes mellitus for 4 years. Coronary angiography revealed severe stenosis in the triple coronary artery system. Immediate myocardial revascularization was considered necessary. We considered that saphenous vein grafts and bilateral internal thoracic artery grafts were unsuitable for this patient. Moreover, Allen's test was positive in the bilateral forearms. Coronary artery bypass surgery consisted of left internal thoracic artery grafting to the left anterior descending artery, right gastroepiploic artery grafting to the right coronary artery, and left ulnar artery grafting to the diagonal branch. No myocardial or hand complications were observed after surgery. Following a review of the Japanese literature, we conclude that our case is the first report of an ulnar artery graft for coronary artery bypass grafting in Japan.     

Angiographic 20-year follow-up of 61 consecutive patients with internal thoracic artery grafts.

OBJECTIVE: To assess the behavior of internal thoracic artery (ITA) grafts versus venous grafts in repeated angiograms up to 20 years. SUMMARY BACKGROUND DATA: Use of ITA grafts to bypass left anterior descending artery stenosis has been shown to be associated with improved survival in patients undergoing coronary artery bypass grafting. METHODS: Sixty-one consecutive patients who received one or two ITA grafts and who underwent surgery from Oct. 5, 1971, to Dec. 18, 1973, in Helsinki University Central Hospital, Finland, were included in this prospective follow-up series. Fifty-six of the patients (92%) also received at least one venous graft. The number of distal anastomoses was 157, of which 47.7% (75) were performed with ITA grafts. The median age of the patients was 47.7 years (range 30.0 to 63.1), and 85% (52) were men. RESULTS: After 20 years of follow-up, 18/20 (90%) of the survivors underwent angiography; the patency rate was 88.9% for ITA grafts and 47.8% for venous grafts. Cumulative graft patency at 20 years, using all the information obtained from repeated angiographic examinations and autopsies, was also calculated to eliminate selection bias. The cumulative 20-year patency rate was 81% for ITA-left anterior descending artery anastomoses, 53.8% for venous graft-right coronary artery anastomoses, and 48.5% for venous graft-left circumflex artery anastomoses. In paired comparisons between anastomoses, the patency time of the ITA-left anterior descending artery anastomoses was on average 2.8 years longer than the venous graft-left circumflex artery patency time and 2.6 years longer than the venous graft-right coronary artery. CONCLUSIONS: Internal thoracic artery grafts, especially in left anterior descending artery anastomoses, should be considered as a primary solution in coronary artery bypass grafting surgery in patients with >10 years of life expectancy; if venous grafting is preferred, further evidence is needed.     

Early experience with minimally invasive direct coronary artery bypass grafting with the internal thoracic artery

OBJECTIVE: Minimally invasive direct coronary artery bypass is performed under direct vision without sternotomy or cardiopulmonary bypass. The technique can be used in both primary and reoperative cases by employing the internal thoracic artery to perform arterial revascularization of the anterior surface of the heart. METHODS: Patients were selected who had significant coronary artery disease limited to 1 or 2 coronary distributions on the anterior surface of the heart. Coronary target vessels were grafted with the internal thoracic artery through a small anterior thoracotomy. After partial heparinization the anastomosis was facilitated by local coronary occlusion and handheld stabilization. RESULTS: Between August 1994 and July 1997, 162 patients underwent minimally invasive direct coronary artery bypass grafting with the internal thoracic artery. The left and right internal thoracic arteries were used for grafting of the left anterior descending artery in 142 patients (88%), the proximal right coronary artery in 7 patients (4%), existing saphenous vein grafts in 5 patients (3%), and diagonal branches in 2 patients (1%). Sequential grafting with the left internal thoracic artery was performed in 2 patients (1%) and bilateral internal thoracic artery grafting was performed in 4 patients (3%). Eight patients (4.9%) died within 30 days after the operation, 3 of cardiac causes. Seven additional patients died during the follow-up period. Nine patients (5.6%) required reintervention for graft stenosis or occlusion during follow-up. Of 141 patients seen 2 or more weeks after the operation, 135 (96%) had resolution of their anginal symptoms at a mean follow-up of 12 months (range 0-31 months). CONCLUSIONS: Anterior minimally invasive direct coronary artery bypass grafting with the internal thoracic artery avoids the risks of repeated sternotomy, aortic manipulation, and cardiopulmonary bypass. There was a low rate of reintervention, and patients had excellent resolution of anginal symptoms. Postoperative length of stay was comparatively short, and continued follow-up will be essential to evaluate long-term graft patency and patient survival.     

Clinical and six-month angiographic evaluation of coronary arterial graft interrupted anastomoses by use of a self-closing clip device: a multicenter prospective clinical trial

OBJECTIVES: To evaluate the safety and effectiveness of a self-closing surgical clip with an interrupted technique in left internal thoracic artery to left anterior descending artery bypass grafting. METHODS: Eighty-two patients were enrolled and treated (February 2000 through August 2001) in a prospective, nonrandomized, multicenter trial. Left internal thoracic artery to left anterior descending artery anastomoses were performed in 60 off-pump coronary artery bypasses (73%), 12 conventional coronary artery bypass grafting (15%), and 10 minimally invasive direct coronary artery bypass (12%) procedures. Angiograms (64 to 383 days, mean 200 days) were obtained on 63 patients (77%). Qualitative and quantitative angiographic assessment was performed by an independent core laboratory. RESULTS: The self-closing surgical clip was used for 82 left internal thoracic artery to left anterior descending artery interrupted anastomoses without the requirement for knot tying or primary suture management. Minimum left internal thoracic artery to left anterior descending artery anastomosis time was 3 minutes. There was one perioperative and one late death (both not heart related) and one reexploration for bleeding unrelated to the anastomotic site. FitzGibbon grades were as follows: A (n = 60, 95.2%), B (n = 3, 4.8%) including one kinked left internal thoracic artery, and O (n = 0, 0%). Quantitative analysis (n = 57) showed mean lumen diameters of left internal thoracic artery proximal to the anastomosis of 2.1 mm, at anastomosis of 2.0 mm, and in the left anterior descending artery distal to the anastomosis of 1.9 mm. The average ratio of the anastomosis to the left anterior descending artery diameter was 1.14 (0.45 to 1.93). Anastomotic stenosis as a percentage of average left internal thoracic artery to left anterior descending artery diameter was -2.3%, comparing favorably with results (23% to 24%) reported from the Patency, Outcomes, Economics, Minimally invasive direct coronary artery (POEM) bypass study. CONCLUSIONS: The interrupted technique, facilitated by a self-closing anastomotic clip, yields favorable 6-month angiographic results when compared with other published studies.     

Multiple coronary aneurysms due to Kawasaki disease in young man--successful triple coronary bypass grafting by utilizing the right gastroepiploic artery, internal thoracic artery and saphenous vein

A 28-year-old man developed acute anteroseptal myocardial infarction. Emergency coronary angiography revealed multiple coronary aneurysms, associated with complete obstruction of left anterior descending artery (LAD) and 50 to 99% stenosis of the right and the circumflex coronary artery (CX). Coronary artery bypass graftings were performed seven weeks after successful emergency intracoronary thrombolysis. The saphenous vein graft was anastomosed to CX, the internal thoracic artery to LAD, the right gastroepiploic artery to RCA just above the bifurcation. Post-operative course was uneventful. On sixth post operative week cardiac catheterization was performed. The study showed all three bypass grafts and native coronary artery to be patent. The patient is now followed up under anticoagulant therapy.     

Assessment of minimally invasive direct coronary artery bypass grafting of the left internal thoracic artery by means of magnetic resonance imaging

OBJECTIVES: We sought to evaluate graft patency, flow, and flow reserve in patients with minimally invasive direct coronary artery bypass surgery of internal thoracic artery grafts by a combined magnetic resonance protocol with a phase-contrast technique and magnetic resonance angiography. METHODS: At 1.5 T (Magnetom Sonata, Siemens), 30 symptomatic patients with 30 left internal thoracic artery grafts were examined 6 years after minimally invasive surgical intervention. Navigator-gated magnetic resonance angiography and contrast-enhanced FLASH-3D magnetic resonance angiography (0.2 mmol gadopentate-diethylene triamine pentetic acid [Gd-DTPA]/kg body weight) was used to assess bypass patency. Phase-contrast flow measurements with retrospective gating were performed in the internal thoracic artery grafts at rest and after stress induction with dipyridamole (0.57 mg/kg body weight). Graft patency was evaluated by means of multidetector computed tomography (Sensation 16, Siemens). RESULTS: Internal thoracic artery grafts were occluded in 5 of 30 patients. In 6 patients the anastomosis to the left anterior descending artery was highly stenotic (>70 % ) at multidetector computed tomography. In patients with regular grafts (multidetector computed tomography), a significant improvement of graft flow ( P < .001) and diastolic/systolic peak velocity ratio ( P < .001) after stress induction was detected. Magnetic resonance angiography combined with flow reserve measurements could differentiate between occluded-stenotic and regular minimally invasive direct coronary artery bypass grafts. CONCLUSIONS: Magnetic resonance imaging allows a combined assessment of bypass patency and flow with flow reserve in patients after the minimally invasive direct coronary artery bypass operation. The protocol of this study might be applicable for the evaluation of graft status in symptomatic patients after revascularization.     

Triple coronary bypass in a child with homozygous familial hypercholesterolemia

Here we report triple coronary bypass procedure in a 12-year-old girl with familial homozygous hypercholesterolemia and extensive coronary atherosclerosis. She had successful cardiopulmonary resuscitation at home by her father 4 months before the operation. Total cholesterol level was 1300 mg/dL initially without antilipidemic treatment. Extensive three vessel disease with right coronary proximal stenosis and left coronary ostial stenoses was determined by angiography. Left internal thoracic artery, left radial artery, and saphenous vein grafts were used for coronary revascularization. Saphenous vein graft to right posterior descending artery, radial artery graft to obtuse marginal artery, and LITA to left anterior descending artery anastomoses were performed consecutively. Ten months after the operation, she is in good condition under intensive antilipidemic therapy and weekly lipid apheresis.     

Comparative analysis of the patency of the internal thoracic artery in the CABG of left anterior descending artery: 6-month postoperative coronary CT angiography evaluation

Objective

To assess the patency of the pedicled right internal thoracic artery with an anteroaortic course and compare it to the patency of the left internal thoracic artery , in anastomosis to the left anterior descending artery in coronary artery bypass grafting by using coronary CT angiography at 6 months postoperatively.

Methods

Between December 2008 and December 2011, 100 patients were selected to undergo a prospective coronary artery bypass grafting procedure without cardiopulmonary bypass. The patients were randomly divided by a computer-generated list into Group-1 (G-1) and Group-2 (G-2), comprising 50 patients each, the technique used was known at the beginning of the surgery. In G-1, coronary artery bypass grafting was performed using the left internal thoracic artery for the left anterior descending and the free right internal thoracic artery for the circumflex, and in G-2, coronary artery bypass grafting was performed using the right internal thoracic artery pedicled to the left anterior descending and the left internal thoracic artery pedicled to the circumflex territory.

Results

The groups were similar with regard to the preoperative clinical data. A male predominance of 75.6% and 88% was observed in G-1 and G-2, respectively. Five patients migrated from G-1 to G-2 because of atheromatous disease in the ascending aorta. The average number of distal anastomoses was 3.48 (SD=0.72) in G-1 and 3.20 (SD=0.76) in G-2. Coronary CT angiography in 96 re-evaluated patients showed that all ITAs, right or left, used in situ for the left anterior descending were patent. There were no deaths in either group.

Conclusion

Coronary artery bypass grafting surgery involving anastomosis of the anteroaortic right internal thoracic artery to the left anterior descending artery has an outcome similar to that obtained using the left internal thoracic artery for the same coronary site.     

Large saphenous vein graft aneurysm with a fistula to the right atrium.

We report on a case of a 65-year-old man who was admitted for anterior chest pain on effort. He had received coronary artery bypass grafting (CABG) surgery 20 years ago with saphenous vein grafts (SVGs) to the left anterior descending artery (LAD) and right coronary artery (RCA). An angiography demonstrated large aneurysmal dilatation of both grafts and a fistulous communication between the middle portion of the right SVG and the right atrium (RA). The aneurysm was excised surgically, and the fistula was closed with the right atrial wall with additional bypass grafts of the left internal thoracic artery (LITA) and gastroepiploic artery (GEA).     

Effect of coronary artery bypass grafting on native coronary artery stenosis. Comparison of internal thoracic artery and saphenous vein grafts

BACKGROUND: The purpose of this study was to investigate the influence of coronary artery bypass grafting on the degree of stenosis of the native coronary artery. METHODS: Experimental design: retrospective data analysis. Setting: University hospital. Patients: consecutive patients undergoing coronary artery bypass grafting (n=52). Bypasses using internal thoracic artery grafts (n=26) and saphenous vein grafts (n=37) to incompletely occluded coronary arteries were studied. Interventions: coronary artery bypass grafting using internal thoracic artery or saphenous vein grafts. Measures: stenosis of the native coronary artery on angiography. RESULTS: Three recipient coronary arteries bypassed with internal thoracic artery grafts (12%) and 14 recipient coronary arteries bypassed with saphenous vein grafts (38%) showed progression of narrowing (p=0.024). Two recipient coronary arteries bypassed with internal thoracic artery grafts (8%) and 13 recipient coronary arteries bypassed with saphenous vein grafts (35%) showed total occlusion (p=0.016). Hypertension, hyperlipidemia, diabetes mellitus, and smoking history did not correlate with progression of stenosis of the native coronary arteries. Graft flow measured during surgery in the saphenous vein grafts was not significantly different between the group that exhibited progression of the native stenosis and the group that did not. CONCLUSIONS: Coronary artery bypass grafting with saphenous vein grafts may result in progression of stenosis of the recipient coronary artery. This is less likely after coronary artery bypass grafting with internal thoracic artery grafts. This difference may be due to the ability of the pedicled internal thoracic artery graft to regulate flow. Thus competitive flow in the native coronary artery is minimized. This has significant clinical implications.     

Reoperative coronary artery bypass grafting without cardiopulmonary bypass

Between October 1995 and Feburary 1997, 2 men and 4 women aged 53 to 75 years (mean, 66.3) underwent reoperative coronary artery bypass grafting without cardiopulmonary bypass. Isolated reoperative circumflex or intermediate artery bypass was performed through a left thoracotomy (n=2), reoperative bypass to the left anterior descending coronary aretery was performed through a median sternotomy (n=3), and bypass to the right coronary artery was performed through an upper median laparotomy (n=1). Single coronary bypass grafting utilizing arterial grafts (left internal thoracic artery: 3, right gastroepiploic artery: 3) was performed in all cases. There were no operative deaths. All cases required neither cathecolamine nor intraaortic balloon pumping). Peri/post operative blood transfusion was necessary in only one case. Postoperative coronary angiography revealed that the 6 arterial grafts were patent. Reoperative coronary artery bypass grafting without cardiopulmonary bypass can be performed with low perioperative morbidity and mortality, easy postoperative management, satisfactory graft patency, and good symptomatic improvement.     

Thoracic endovascular aortic repair and off-pump coronary artery bypass grafting after renal transplantation: a case report

Twelve years after receiving a renal transplant, a 50-year-old woman developed asthmatic symptoms. Chest CT revealed a descending thoracic aortic aneurysm. She had undergone percutaneous coronary intervention to treat the left anterior descending artery 10 years earlier. Coronary artery angiography revealed restenosis of the left anterior descending artery (99%, #6 in-stent). Because cardiopulmonary bypass may cause problems for transplanted kidney, we performed off-pump coronary artery bypass grafting (left internal thoracic artery to left anterior descending artery) and thoracic endovascular graft placement to treat the aortic aneurysm. Considering that the artery of the transplanted kidney was attached to the right iliac artery, and then the left common femoral artery was selected as the access root for GORE TAG(?) endografts (34 × 200 and 34 × 150 mm) (stentgrafts were deployed for the descending aortic artery). Postoperative angiography showed a patent bypass graft. Postoperative CT confirmed the absence of endoleaks. The postoperative course was uneventful, and she was discharged without complications. Ischemic heart disease and descending thoracic aortic aneurysm in recipients of kidney transplants can be treated using off-pump coronary bypass grafting and thoracic endovascular graft placement. The transplanted kidney was protected without using cardiopulmonary bypass (CPB).     

川崎病冠状动脉病变及搭桥手术

目的 探讨川崎病后严重冠状动脉病变及搭桥手术（ＣＡＢＧ）后的近期及远期效果。方法随访发现,６例川崎病后严重冠状动脉病变的病儿均有左冠状动脉前降支（ＬＡＤ）病变,右冠状动脉（ＲＣＡ）病变５例,左冠状动脉回旋支（ＬＣＸ）病变３例,左冠状动脉主干（ＬＭＴ）病变２例,心肌梗死３例。共行１５支ＣＡＢＧ;单支２例,３支３例,４支１例;左胸廓内动脉（ＬＩＴＡ）至ＬＡＤ６例;右胸廓内动脉（ＲＩＴＡ）至ＬＡＤ１例。     

Effect of flow competition on internal thoracic artery graft: postoperative velocimetric and angiographic study

OBJECTIVES: To assess the effects of competitive blood flow on internal thoracic artery grafts, we investigated postoperative flow velocity characteristics and angiographic findings of the grafts with various grades of native coronary artery stenosis. METHODS: Fifty patients who had an internal thoracic artery graft to the left anterior descending artery underwent intravascular Doppler graft velocimetry during postoperative angiography. Patients were divided into 3 groups according to the grade of native coronary stenosis: group H (28 patients), 80% stenosis or greater; group M (16 patients), 60% to 79% stenosis; and group L (6 patients), 40% to 59% stenosis. Phasic flow velocity of the grafts was measured with an intravascular Doppler ultrasound-tipped guide wire during angiography. Graft flow volume was calculated from the diameter and the average peak velocity. RESULTS: Average peak velocity (group H, 27.1 +/- 8.6 cm/s; group M, 16.9 +/- 3.9 cm/s; group L, 7.2 +/- 3.7 cm/s), distal graft diameter (group H, 2.27 +/- 0.23 mm; group M, 2. 00 +/- 0.28 mm; group L, 1.07 +/- 0.27 mm), and calculated graft flow volume (group H, 33.1 +/- 12.0 mL/min; group M, 16.2 +/- 5.8 mL/min; group L, 2.3 +/- 2.0 mL/min) significantly differed among the 3 groups. Graft flow in diastole and systole also differed among the 3 groups. CONCLUSIONS: Competitive blood flow reduces internal thoracic artery graft flow and diameter according to the grade of the native coronary artery stenosis. These data suggest that grafting the internal thoracic artery to the coronary artery with stenosis of a low grade can cause graft atrophy and failure.     

Reoperative Coronary Artery Bypass Grafting Via a Left Thoracotomy and a Small Laparotomy Without Cardiopulmonary Bypass: Report of a Case

A 66-year-old woman with aortic stenosis underwent an aortic root replacement with a composite graft and coronary artery reconstruction 2 years before presentation. On coronary angiography performed 2 years after operation, saphenous vein graft (SVG) to right coronary artery and SVG to first diagonal branch had both become totally occluded. SVG to left anterior descending artery showed 75% stenosis on the heel side of the distal anastomosis. The patient underwent a second coronary artery bypass via a left thoracotomy (the left internal thoracic artery was anastomosed to the first diagonal branch by interposing it with the left radial artery) and a small laparotomy (the right gastroepiploic artery was anastomosed to the right coronary artery) without a cardiopulmonary bypass. This approach is preferable to avoiding both a resternotomy and cardiopulmonary bypass in patients requiring repeat surgery. Received: September 29, 2000 / Accepted: May 15, 2001