Influence of Aspirin and Dipyridamole on Patency of Coronary Artery Bypass Grafts

A prospective randomized trial was performed to determine if the administration of inhibitors of platelet function would improve the patency of coronary artery bypass grafts. Patients were operated on for intractable angina with angiographically demonstrable lesions. The left internal mammary artery (IMA) was used for bypass of lesions of the left anterior descending coronary artery (LAD). Saphenous vein grafts were used for the LAD if the IMA was inadequate and for all other vessels. Treated patients received 1,300 mg of aspirin and 100 mg of dipyridamole (Persantine) orally each day. Control patients received neither drug. Patients returned 3 to 6 months after operation for repeat angiography. Results were analyzed by chi-square.One hundred seventy-four patients entered the study from June, 1973, through December, 1975, and 113 were analyzed. In the control group, 66 patients had 27 IMA-LAD grafts and 93 saphenous vein grafts. In the treatment group, 47 patients underwent 18 IMA-LAD grafts and 75 saphenous vein grafts. Ninety-eight of the 120 grafts (82%) were patent in the control group, and 87 of 93 grafts (94%) were patent in the treatment group (x² = 6.34, p < 0.02). Of the 45 IMA-LAD grafts in both groups, only 1 was occluded, a patency of 98%. In the control group, 72 of 93 saphenous vein grafts (77%) were patent. In the treatment group, 69 of 75 (92%) were patent (x² = 6.54, p < 0.02). The results of the study show a 15% difference between the two groups in the early patency of saphenous vein grafts. We continue to use aspirin and dipyridamole to improve the patency of saphenous vein bypass grafts.     

Acetylsalicylic acid and dipyridamole improve the early patency of aorta-coronary bypass grafts. A double-blind, placebo-controlled, randomized trial

A total of 125 patients undergoing aorta-coronary bypass grafting for disabling angina were randomized to receive either 330 mg of acetylsalicylic acid (aspirin) plus 75 mg of dipyridamole three times daily or a placebo for 6 months postoperatively. In addition, all patients were given warfarin for 3 months. Repeat angiography was performed at 6 months in 103 patients. In the treatment group 95 grafts were implanted in 48 patients, of which 87 were patent (91.6% patency rate). This figure compares with 88 grafts patent out of 118 implanted in 55 patients in the placebo group (74.6% patency rate) (p less than 0.01). We conclude that antiplatelet therapy improves the early patency of saphenous vein aorta-coronary bypass grafts.     

Pleuropulmonary morbidity: internal thoracic artery versus saphenous vein graft

Although use of the internal thoracic artery (ITA) for coronary artery bypass grafting results in superior graft patency and improved patient survival, our initial clinical observations suggested an increased incidence of pleuropulmonary morbidity with its use. One hundred consecutive patients with left ITA grafts were studied prospectively and compared with a consecutive retrospective group of 100 patients undergoing coronary artery bypass grafting with saphenous vein grafts only. Preoperative, postoperative day (POD) 2, POD 6, and postoperative week 8 chest roentgenograms were analyzed for atelectasis and effusion. Postoperative left lower lobe atelectasis was common in both groups on both POD 2 (saphenous vein, 43%, versus ITA, 53%; not significant) and POD 6 (saphenous vein, 40%, versus ITA, 41%; not significant). There was a significantly higher incidence of pleural effusion on POD 6 in the ITA group (84% versus 47%; p less than 0.05) but most of these were small. There was more chest tube drainage (1,413 versus 1,028 mL; p less than 0.01) and a greater need for secondary thoracostomy or thoracentesis (4% versus 0%) in the ITA group. The left pleural space was opened in 67 of the 100 ITA patients but pleurotomy did not appear to influence postoperative morbidity. We conclude that use of the internal thoracic artery for coronary artery bypass grafting results in a small but significant increase in pleuropulmonary morbidity.     

Results of internal thoracic artery grafting over 15 years: single versus double grafts

One hundred consecutive patients who had coronary artery bypass grafting using both internal thoracic arteries (ITAs) and saphenous veins, operated on during a 3-year period between 1972 and 1975, have been compared retrospectively with a series of 100 patients operated on during the same period who had one ITA graft along with saphenous vein grafts. The two groups were similar with respect to age, sex, risk factors for coronary artery disease, angina class, extent of coronary artery disease, left ventricular function, number of coronary bypass grafts performed, and completeness of revascularization. Single ITA operative mortality was 2% and double ITA, 9% (p = NS). The mean follow-up of hospital survivors was 14.4 +/- 2.7 years; all but 7 patients had follow-up for at least 10 years. At 13 years, the actuarial patency of the right ITA was 85% and the left ITA, 82%. These data strongly suggest a survival benefit for patients with double ITA grafts among hospital survivors (74% versus 59%; p = 0.05). Patients receiving two ITA grafts had a significant freedom from subsequent myocardial infarction (75% versus 59%, p less than 0.025), recurrent angina pectoris (36% versus 27%, p less than 0.025), and subsequent total ischemic events (32% versus 18%, p less than 0.01). These data also suggest improved freedom from coronary artery interventional therapy (percutaneous transluminal coronary angioplasty and reoperation) when two ITA grafts were used. These results support the use of bilateral internal thoracic artery grafting in selected patients.     

Long-term results of coronary artery bypass grafting: comparison of angiographic evaluation of internal thoracic artery and saphenous vein grafts

The long term (10 to 15 years) results of coronary artery bypass grafting (CABG) were studied in 20 patients. The duration of follow-up was ranged from 130 to 170 months with mean 146.4 months. Ten out of 20 patients underwent coronary angiography (CAG), which disclosed that the late patency of saphenous vein (SV) grafts was 68.8% (11/16), but 54.5% (6/11) of patent SV grafts showed atherosclerotic changes such as irregularity and localized narrowing. On the other hand, internal thoracic artery (ITA) grafts were all patent without any atherosclerotic luminal changes. We recognized that ITA grafts were superior to SV grafts from an angiographic standpoint of view in the long term in Japan.     

Utility and limitation of sequential saphenous vein graft for complete revascularization in coronary artery surgery

Multiple bypass grafting in complete myocardial revascularization requires frequently the use of sequential saphenous vein grafts as well as arterial grafts. To expect the favorable good clinical results of revascularization, therefore, refined surgical technique for saphenous vein grafting and proper selection of suitable coronary arteries for bypass are important. Between January 1989 and April 1990, 91 patients underwent CABG utilizing internal thoracic arteries (ITA) in 79% and SVG in 99% of the patients with an average of 3.3 anastomoses per patients. Postoperative angiography was performed 4 or 8 weeks after surgery. Early patency rates were 92% (204/221) in overall anastomotic sites, 96% (52/54) in ITA and 91% (152/167) in SVG respectively. There was no difference in patency rates between individual (90%) and sequential (92%) grafts. In sequential grafting, however, patency rate of side-to-side anastomosis was higher than that of end-to-side anastomosis. Patency rates of the grafts were also evaluated in terms of the sizes of coronary arteries and intraoperative graft flows. These studies lead to the following conclusions: In individual grafting, the acceptable patency rate can be expected when the graft flow exceeds 30 ml/min even if the internal diameter of coronary artery is less than 1.5 mm. In sequential grafting, on the other hand, a diameter more than 1.5 mm is desirable for the coronary artery at the site of end-to-side anastomosis.     

Internal mammary artery grafts: technical factors influencing patency

Eight hundred fourteen patients with internal mammary artery (IMA) coronary artery bypass grafts have been restudied 961 times with coronary arteriography, primarily to evaluate the patency of the grafts in the setting of symptomatic coronary occlusive disease. Their records were reviewed to assess graft patency as related to the technical aspects of coronary artery bypass surgery. Patency was evaluated using life-table analysis of the data. The method of harvesting the IMA played no role in patency. The left anterior descending coronary artery was the recipient coronary artery with the highest patency rate. The left IMA had a significantly higher patency rate than the right IMA. As a group, the IMAs had a significantly higher patency rate than saphenous vein grafts. However, there was no difference between right IMA grafts and saphenous vein grafts. The mammary artery grafts that remained patent throughout the study had a significantly higher blood flow after bypass than did those that became occluded (43.0 +/- 0.9 versus 28.9 +/- 1.8 ml/min; p less than .001).     

Long-term (5 to 12 years) serial studies of internal mammary artery and saphenous vein coronary bypass grafts

Serial arteriograms were obtained in 501 patients after coronary bypass grafting. Study I within 5 years of operation (mean interval 15 months) and Study II more than 5 years after (mean interval 88 months, range 60 to 147 months). One hundred patients received both internal mammary artery and saphenous vein grafts: 37, mammary artery grafts only, and 364, vein grafts only. In Study I, 645 (82%) of 786 vein grafts were patent, 42 (5%) stenotic or irregular, and 99 (13%) occluded. Of 140 mammary artery grafts, 136 (97%) were patent, two (2%) stenotic, and two (2%) occluded. Of the 645 vein grafts patent in Study I, 357 (55%) remained patent in Study II, 119 (18%) were stenotic or irregular, and 169 (26%) were occluded. Of 136 mammary artery grafts patent in Study I, 130 (96%) were unchanged, one was stenotic, and five (4%) were occluded in Study II. Early vein graft patency was influenced by the coronary artery grafted and by angina. Progression of vein grafts patent at Study I to stenosis or occlusion at Study II was associated with increasing postoperative interval (p less than 0.00001), interval myocardial infarction (p less than 0.001), angina (p less than 0.001), diabetes (p less than 0.004), hypercholesterolemia (p less than 0.006), and hypertriglyceridemia (p less than 0.02); it was not influenced by the coronary artery grafted. Within 5 years of operation, mammary artery graft patency exceeded vein graft patency. Between 5 and 12 years after operation, the attrition rate of vein grafts greatly exceeded that of mammary artery grafts (p less than 0.0001).     

Improved patency in vein grafts harvested with surrounding tissue: results of a randomized study using three harvesting techniques

BACKGROUND: The technique of harvesting the saphenous vein for coronary artery bypass grafting influences the fate of vein grafts. The patency rate of a novel "no-touch" technique in which the vein is harvested with a pedicle of surrounding tissue and not distended was compared with two other techniques. METHODS: One hundred fifty-six patients who underwent coronary artery bypass grafting were randomized to three saphenous vein harvesting groups: group C (conventional)--the vein was stripped, distended, and stored in saline; group I (intermediate)--the vein was stripped, local application of papaverine was used instead of distention, and the vessel was then stored in heparinized blood; and group NT (no-touch)--the vein was harvested with surrounding tissue, not distended, and stored in heparinized blood. Surgical and clinical factors that might influence graft occlusion were recorded. One hundred twenty-seven vein grafts in group C, 116 in group I, and 124 in group NT, as well as 118 left internal mammary artery grafts, were angiographically assessed at 18 months mean follow-up time. RESULTS: The vein graft patency was 88.9% in group C, 86.2% in group I, and 95.4% in group NT. There was a statistically significant difference between the patency of the single-vein grafts in NT and the other two groups (p = 0.025). The higher the flow, the better the patency irrespective of the technique used. A higher attrition rate was found in vein segments taken from the knee area in group I. Poor vein quality affected patency in all groups. Forty-seven of all 51 sequential grafts (92.2%) were patent. The patency of left internal mammary artery grafts was 108 of 118 (91.5%). CONCLUSIONS: We conclude that preservation of the surrounding tissue of the saphenous vein using this no-touch technique abolishes venospasm intraoperatively and plays an important role in maintaining vein graft function and patency.     

Rationale for off-pump coronary revascularization to small branches--angiographic study of 1,283 anastomoses in 408 patients

BACKGROUND: Off-pump coronary artery bypass grafting (OPCAB) has gained wide acceptance in tandem with the development of the stabilizer and associated operative techniques. However bypass grafting to the small branches of a beating heart is technically demanding and remains controversial. In the present study we evaluated the graft patency and quality of anastomoses to small coronary arteries by early postoperative angiography. METHODS: Between March 2000 and December 2002 a total of 1,328 anastomosed sites to coronary branches were studied angiographically in 404 patients representing 88.6% of all cases who underwent OPCAB in this period. The coronary artery branches were categorized as large (>1.5 mm, group L: 1,028 anastomoses sites) or small (< 1.5 mm, group S: 300 sites) by intraoperative measurement. As in situ grafts the internal thoracic artery (ITA) and the gastroepiploic artery (GEA) were used at 504 and 28 distal anastomosis sites respectively. The radial artery (RA) was used as a composite graft for 739 distal anastomosis sites. Sequential bypass grafting was performed at 388 anastomosis sites in side-to-side fashion. Arterial grafts were used in 96.1% of total bypass grafting. RESULTS: The percentage of male gender was 78.3% in group S and 87.2% in group L (p = 0.025). The ITA was used in 43.7% of group L and 18.3% of group S (p < 0.0001). The RA was used in 49.4% of group L and 77% of group S (p < 0.0001). The overall patency and stenosis free rates (FitzGibbon Type A) were 97.2% and 96.2%. Graft patency and stenosis free rates in group S (96.7% and 93.3%) were as good as those in group L (97.5% and 97.1%). In group S, the patency and stenosis free rates of SV grafts were 71.4% and 57.1%. On the other hand, those of ITA grafts were 100% and 98.3% (p = 0.53 vs. saphenous vein graft [SVG]) and RA grafts were 95.8% and 92.1% (p = 0.61 vs. SVG) respectively. In group S, the graft patency and stenosis free rates of bypass to the obtuse marginal (OM) (93.7% and 87.5%) were slightly lower than those to other implantation sites left anterior descending (LAD: 100% and 97.3%; PL: 96.5% and 92.3%; DI: 98.0% and 96%; PDA: 97.0% and 97.0%; right coronary artery [RCA]: 100% and 100%) although there was no statistical significance. The graft patency and stenosis free rates were slightly better with side-to-side anastomosis than with end-to-side anastomosis (side-to-side: 98.1% and 95.8% vs. end-to-side 96.3% and 86.3%) in group S. CONCLUSIONS: OPCAB to small coronary artery branches with arterial grafts provided satisfactory graft patency and stenosis free rates.     

The fate of arm veins used for aorta-coronary bypass grafts

Arm veins have been a common second choice conduit for those patients having insufficient saphenous veins for coronary bypass operations. To define the patency and durability of arm vein grafts, we reviewed our patients with one or more arm vein grafts used for coronary revascularization between 1974 and 1982. A total of 59 patients required at least one arm vein graft and 51 are presently alive. Postoperative arteriograms were obtained in 28 patients. Of 56 arm vein grafts used, 32 (57%) were patent and 24 (43%) had failed at 2 years. Seven of the patent grafts had a localized area of stenosis. Sixteen internal mammary artery grafts also had been used in this group of patients, and 15 (93%) were patent. We conclude that arm vein grafts have a high failure rate and are not as dependable as saphenous vein grafts or internal mammary artery grafts.     

Has the in situ right internal thoracic artery been overlooked? An angiographic study of the radial artery, internal thoracic arteries and saphenous vein graft patencies in symptomatic patients.

OBJECTIVE: The right internal thoracic artery is being used infrequently despite favorable observational angiographic data. Conversely, the radial artery utilization has increased with only limited data available. The purpose of this paper is to re-evaluate the roles of the right internal thoracic artery and the radial artery grafts. METHODS: We reviewed all ischemia-directed coronary angiographic procedures from January 1996 to December 2003. A total of 219 patients had primary coronary artery bypass grafting with an internal thoracic artery and a radial artery as two of the bypass grafts. Six hundred and seventy-nine (679) graft angiograms (45 saphenous vein, 363 radial artery, 54 right internal thoracic artery and 217 left internal thoracic artery) were studied. The mean period from operation to re-angiogram was 1104+/-761 days. Angiographic outcomes were divided into groups as: (1) patent (<50% stenosis) or (2) failed (>or=50% stenosis, string sign or occluded). A generalized linear mixed model was used to analyze predictors of graft patency. Turnbull's estimates of cumulative patency were used to compare graft failure rates over time. RESULTS: A total of 632/679 (93%) grafts were patent and 47/679 (7%) grafts had failed. Empirical saphenous vein graft patency was 40/45 (89%), radial artery patency 329/363 (91%), right internal thoracic artery patency 51/54 (94%) and left internal thoracic artery patency 212/217 (98%). Pairwise comparisons of patency from the generalized linear mixed model were: LITA>RITA, OR=1.5 (P=0.5); LITA>RA, OR=5.7 (P<0.001); LITA>SV, OR=6.5 (P<0.001); RITA>RA, OR=3.9 (P=0.01); RITA>SV, OR=4.4 (P=0.01); RA>SV, OR=1.1 (P=0.7). Five-year patency estimates from the Turnbull's model were the left internal thoracic artery (95.9%), right internal thoracic artery (91.2%), the radial artery (90.6%) and the saphenous vein (81.8%). CONCLUSIONS: Consideration should be given to the routine use of both internal thoracic arteries for coronary artery bypass grafting. When additional grafts are required, there is no evidence to suggest that either the radial artery or saphenous vein is superior.     

Improving patency of coronary conduits "valveless" veins and/or arterial grafts

BACKGROUND: Veins used for coronary artery bypass operation have a well-documented limited long-term patency. Internal thoracic artery (ITA) grafts have shown exceptional "durability." Assumptions were made that other arterial conduits have similar characteristics. AIM OF THE STUDY: The purpose of this article is to compare different conduits long-term patency including saphenous veins to other available arterial conduits: inferior epigastric artery (IE), right gastroepiploic artery (RGEA), and radial artery (RA). METHODS: Recent studies have shown that radial artery bypasses have lower patency rate than saphenous veins. Flow patterns, physiological flow characteristics are reviewed including native vessel disease and area of myocardium supplied. In the case of venous bypasses, the primary culprit of failure seemed to be the quality of the vein itself and the reverse venous valves in the conduit resulting in: (a) trapping-hypertension, (b) thrombosis, (c) turbulence, (d) intimal damage, (e) mismatching in size. RESULTS: Clinical follow-up of our patients up to 8 to 11 years (average 8.9 years) have proved the superior characteristics of the so-called "good veins." In a retrospective study of 436 patients sequential, valveless veins patency was 88.6% versus 72% of reversed valvular segments (p < 0.01). Patients' survival seemed to be significantly improved if these veins were combined with ITA grafts. Patients' survival with one valveless limb HS + ITA was 78% versus HS + SV 52% (p < or = 0.0017) and HS + ITA versus HS + ITA + SV (p < 0.0057). CONCLUSION: Selective decision-making of the surgeon at the time of the operation is required to choose the best conduit to be able to perform the best operation with the best long-term result.     

High early patency of saphenous vein graft for coronary artery bypass harvested with surrounding tissue

BACKGROUND: Surgical trauma to the saphenous vein, used as a conduit for coronary artery bypass grafting, affects their occlusion rate. This study evaluates the early patency of saphenous vein grafts harvested with a pedicle of surrounding tissue that protects the vein from spasm and trauma. METHODS: Fifty-two patients underwent coronary artery bypass grafting with saphenous veins harvested with surrounding tissue. Forty-five patients, who received a total of 124 vein grafts and 42 left internal mammary arteries, underwent angiographic follow-up at a mean of 18 months (9 to 24 months). RESULTS: Patency for saphenous vein grafts was 95.4% and for left internal mammary arteries, it was 93.3%. Twenty-nine of 30 (96.7%) vein grafts anastomosed to arteries 2.0 mm or more, 65 of 67 (97%) grafts to 1.5 mm, and 10 of 13 (77%) anastomosed to 1-mm arteries were patent. Nineteen of 22 (86.4%) vein grafts with flow rates 20 mL/min or less, 32 of 34 (94.1%) with flow between 20 and 40 mL/min, and 50 of 51 (98%) with flow more than 40 mL/min were patent. Other registered surgical and clinical factors did not contribute to vessel occlusion. CONCLUSIONS: Early patency rate of saphenous veins harvested with surrounding tissue is very high, even in saphenous vein grafts demonstrating low blood flow. Preservation of graft endothelium using our harvesting technique may be the explanation of this success.     

Thermal Coronary Angiography for Intraoperative Patency Control of Arterial and Saphenous Vein Coronary Artery Bypass Grafts: Results in 370 Patients

ABSTRACT Background and aim of the study: Early graft failure is often associated with technical failures and is therefore potentially avoidable. We used thermal coronary angiography (TCA) for intraoperative graft patency control in 370 patients undergoing routine coronary artery bypass graft surgery to determine whether consequent intraoperative bypass graft control may result in improved patency rates. Methods: The temperature differences generated in between the myocardium and the grafts by injecting cold cardioplegic solution into the proximal end of a vein graft or by warmer blood running through an internal thoracic artery (ITA) graft were detected using three different infrared camera systems. The resulting “heat pictures” were evaluated for anastomotic patency and to outline graft anatomy. Results: A total of 693 vein grafts were visualized. In 9.4% TCA failed to produce usable images. In the remaining 628 grafts, TCA revealed intraoperative patency in 98.8%. Out of 370 ITA grafts, only 14 could not be sufficiently visualized by TCA. Nineteen ITA occlusions (5.3%) were found: 5 intimal flaps; 11 suture imposed strictures; and 3 proximal ITA occlusions. All occluded grafts were subsequently revised or replaced. All sequential ITA as well as 15 right ITA grafts proved to have patent anastomoses. Conclusion: Using TCA an early graft dysfunction rate of 1% for vein grafts and 5.3% for ITA grafts could be demonstrated. Most occlusions were due to technical mistakes at the distal anastomosis. TCA outlines grafts and the attached coronaries by temperature differences without the need for a contrast agent. There is no interference with the surgical procedure. It is an ideal, noninvasive method to immediately document the success or failure of myocardial revascularization.     

Off-pump coronary artery bypass grafting for the circumflex coronary artery via the left thoracotomy in redo CABG with the patent left internal thoracic artery graft to the left anterior descending artery.

Five patients had undergone off-pump coronary artery bypass grafting (CABG) as redo CABG via the left thoracotomy for the lesions of the left circumflex coronary arteries. In all patients, the internal thoracic artery (ITA) grafts to the LAD were well patent and acting significantly important in coronary circulation, however, ischemia due to the lesion of the LCX was significant. The saphenous vein grafts or the radial artery grafts were used as the materials of the grafts. The proximal ends of these grafts were anastomosed to the descending aorta. The procedures were completed successfully in all the patients and the excellent patency was shown angiographycally even in the long-term period after the surgery. Necessity of graft surgery only for the LCX lesion would be a rare occasion for a surgeon; however, these results suggest that the procedure is simple and less risky, which would encourage the surgeon to perform it in clinical situation.     

Long-term patency of coronary grafts with endoscopically harvested saphenous veins determined by contrast-enhanced electron beam computed tomography

OBJECTIVES: We determined the long-term patency rates of coronary artery grafts with endoscopically harvested saphenous veins. METHODS: Patency rates were established in 51 patients with 130 distal saphenous vein grafts using contrast-enhanced electron beam computed tomography at 3.74 +/- 0.65 years after coronary artery bypass grafting. A similar group of 50 patients with 131 distal grafts were studied prospectively using the same methodology at 0.7 +/- 0.19 years after coronary artery bypass grafting. RESULTS: The overall patency rates were 95.4% in the retrospective group and 95.3% in the prospective group. Sequential grafts tended to have a patency advantage over independent grafts. CONCLUSIONS: These data compare favorably with reported patency rates for traditionally harvested saphenous veins. Endoscopic saphenous vein harvesting, in addition to previous favorable reports on pain, complications, and costs, is now shown to provide comparable or better patency rates in comparison with traditionally harvested veins.     

Internal mammary artery bypass graft--long-term patency rate and follow-up

Between December, 1968, and January, 1974, 814 internal mammary artery and 351 saphenous vein bypass graft procedures were performed in 628 patients. Operative mortality during the past 3 years has been 1.7%. Internal mammary artery bypasses were performed to the anterior descending, circumflex, obtuse marginal, distal right, and posterior descending right coronary arteries. Ninety-one patients having 137 internal mammary artery and 32 saphenous vein grafts were studied angiographically 12 to 36 months postoperatively. All but 2 internal mammary artery bypasses were patent, a patency rate of 98.5%; 27 of the 32 saphenous vein bypasses in this group were patent (84.3%). The majority of the internal mammary artery bypasses were to distal coronary arteries, while the saphenous veins were used primarily for proximal anastomosis. Cineangiographic volume/flow studies were also performed. The average flow in the more distal internal mammary artery bypasses was 61 ml. per minute as compared with 91 ml. per minute in the proximal saphenous vein grafts.     

The correlation between flow pattern during cardiopulmonary bypass and patency of the coronary artery bypass grafts

Recently the availability of transit time flow measurement (TTFM) is reported especially in off-pump coronary artery bypass grafting (CABG). But little is known about TTFM findings in on-pump CABG. We examined the correlation between the TTFM flow pattern and the angiography findings in on-pump CABG. The subjects consisted of 52 patients who underwent on-pump CABG and angiography early after operation. In these patients, 55 internal thoracic artery (ITA), 17 gastroepiploic artery (GEA), 13 saphenous vein graft (SVG) and 41 radial artery (RA) were tested with TTFM during cardiopulmonary bypass (CPB). TTFM demonstrated a diastolic filling pattern in 53 ITA, 16 GEA, 13 SVG and 36 RA. The angiography revealed that all these grafts were perfectly patent with the exception of a GEA with a flow competition pattern. TTFM revealed an abnormal flow pattern in 2 ITA (these 2 grafts were revised during CPB and the angiography demonstrated their perfect patency), 1 GEA (to and fro pattern), 0 SVG and 5 RA (the abnormal pattern was due to graft spasm in 3 of 5, and the angiography revealed their perfect patency, however, the angiography detected stenosis in the remaining 2 grafts). The present study found that the TTFM flow pattern during CPB correlated well with the angiography findings. TTFM during CPB was useful to detect graft failure, and grafts were revised safely during CPB.     

Late results of two hundred seventeen femoropopliteal bypasses to isolated popliteal artery segments

A 10-year-experience of 217 femoropopliteal bypasses to isolated popliteal artery segments in 207 patients is reported. Thirty-three femoropopliteal bypasses (15%) were performed with reversed saphenous vein and 184 (85%) with polytetrafluoroethylene grafts. Operative indications were gangrene in 121 (56%), nonhealing ulceration in 40 (18%), ischemic rest pain in 51 (24%), and claudication in 5 (2%) cases. The 5-year primary graft patency rate of these bypasses was 59% (reversed saphenous vein, 74%; polytetrafluoroethylene, 55%; p less than 0.05), the secondary 5-year graft patency rate was 61% (reversed saphenous vein, 79%; polytetrafluoroethylene, 56%; p less than 0.05), and the 5-year limb salvage rate was 78% (reversed saphenous vein, 78%; polytetrafluoroethylene, 78%). The 30-day operative mortality rate was 10%, and the 5-year patient survival rate was 38%. Eleven patients (5%) required lower extremity amputation because of progressive gangrene or extensive infection despite a patent bypass to an isolated popliteal artery segment. We conclude that femoropopliteal bypasses to isolated popliteal artery segments (1) have acceptable 5-year graft patency and limb salvage rates; (2) should be performed with reversed saphenous vein grafts when possible; (3) may be performed with polytetrafluoroethylene grafts if necessary, with a resulting limb salvage rate equal to that of reversed saphenous vein grafts; and (4) require sequential extension to an infrapopliteal artery in up to 20% of patients. In addition, the presence of an isolated popliteal artery segment is associated with a high operative mortality rate and limited life expectancy because of coronary artery disease.