Hisayoshi Suma

Arteriosclerosis of the gastroepiploic and internal thoracic arteries

Arteriosclerosis of the right gastroepiploic artery (GEA) and the internal thoracic artery (ITA) were compared by pathological observation. Specimens were obtained from 35 patients who underwent coronary artery bypass grafting with simultaneous use of these two kinds of arterial grafts. Degree of arteriosclerosis was classified in five categories: 0, normal; 1, luminal narrowing less than 25%; 2, luminal narrowing between 25% and 50%; 3, luminal narrowing greater than 50%; and 4, overt atherosclerosis with ulceration or calcification. The number of arteries with degree 0, 1, 2, 3, and 4 was 16 (46%), 15 (43%), 3 (9%), 0, and 1 (3%) in GEA and 27 (77%), 8 (23%), 0, 0, and 0 in ITA, respectively. Incidence of degree 0 was higher in ITA, but differences were not significant. The mean wall thickness was 0.30 +/- 0.13 mm in GEA and 0.21 +/- 0.07 mm in ITA (p less than 0.05). In 23 patients who underwent postoperative angiography, all 46 arterial grafts were patent without focal stenosis. We conclude that GEA has slightly more intimal thickening than ITA, but significant luminal narrowing caused by arteriosclerosis is rare. Gastroepiploic artery can be expected to be a suitable conduit for coronary artery bypass grafting.

Pharmacological response of internal mammary artery and gastroepiploic artery

Pharmacological response of coronary artery bypass conduit is of great importance. This study was designed to clarify the contractile properties of internal mammary artery and gastroepiploic artery obtained from coronary revascularization. The response to ergonovine, serotonin, and phenylephrine was examined by isometric contraction recording apparatus. The concentration-response relation of both internal mammary artery and gastroepiploic artery to ergonovine, serotonin, and phenylephrine showed similar sigmoid curves. There were no significant differences in developed tension between internal mammary artery and gastroepiploic artery at any concentration for any agent. There were no significant differences in the 50% effective dose value for any agent between internal mammary artery and gastroepiploic artery. Internal mammary artery and gastroepiploic artery are reported to be similar in terms of size, flow capacity, and freedom from atherosclerosis. This study shows their equivalence from a pharmacological viewpoint.

Coronary artery bypass grafting in patients with calcified ascending aorta: Aortic no-touch technique

To perform coronary artery bypass grafting safely for patients with calcified ascending aorta, an aortic no-touch technique, which consisted of (1) maximal utilization of in situ arterial grafts (2) fibrillatory arrest without aortic cross-clamp, (3) left ventricular venting through the right superior pulmonary vein, and (4) femoral artery perfusion, was attempted in 3 patients. All were men, aged 64, 70, and 56 years, respectively, with triple-vessel disease with severe atherosclerotic lesion in the ascending aorta. Bilateral internal mammary arteries and the right gastroepiploic artery were used in all patients. All patients survived without evidence of perioperative myocardial infarction or cerebrovascular accident.

Coronary artery reoperation through the left thoracotomy with hypothermic circulatory arrest

BACKGROUNDnThe left thoracotomy approach to avoid injury of the patent old graft and the myocardium with mid sternal reentry at coronary artery reoperation.nnnMETHODSnThe left thoracotomy approach was used in 13 patients. There were 11 men and 2 women with a mean age of 63 years, ranging from 39 to 75 years. Three patients were having their third coronary bypass operation. In 11 patients, distal anastomoses were performed under circulatory arrest with moderate hypothermia. In the other 2 patients, distal anastomoses were performed on a beating heart. No aortic cross-clamp was applied in all patients. The mean number of distal anastomoses was 1.8; the grafted vessels were 11 anterior descending, 3 diagonal, 8 circumflex, and 1 posterolateral coronary arteries. Used grafts were 17 saphenous veins, 4 left internal thoracic arteries, and 2 gastroepiploic arteries. Inflow sites of the free graft were descending aorta in 10 patients and left subclavian artery in 3 patients.nnnRESULTSnAll patients were alive and well at the mean follow-up of 16 months, and all grafts were patent.nnnCONCLUSIONSnThe left thoracotomy approach is safe and effective for reoperation on the left coronary artery system, and circulatory arrest is convenient and safe for performing distal anastomosis.

Availability of the in situ right gastroepiploic artery for coronary artery bypass

The right gastroepiploic artery (GEA) has been successfully used as a coronary bypass graft recently. We examined the in situ GEA graft length required from the pyloric portion to the site of coronary anastomosis at the time of operation. Measured GEA length was 17.0 +/- 1.7 cm for the posterior descending artery anastomosis in 17 patients, 17.8 +/- 1.7 cm for the main right coronary artery anastomosis in 13 patients, 22.0 +/- 2.3 cm for the posterolateral branch anastomosis in 7 patients, and 21.0 cm for the left anterior descending artery anastomosis in 1 patient. We examined 228 randomly selected abdominal angiograms and measured the internal diameter of the right GEA at every 2-cm interval from its origin. Probability of availability of the in situ GEA graft for each site of anastomosis was 97% to the right coronary artery and 88% to the anterior descending or the circumflex artery when the internal diameter of GEA was 1.5 mm or greater. From an anatomical standpoint, we concluded that the GEA can be assumed available without preoperative angiography.

Bovine internal thoracic artery graft for myocardial revascularization : late results

From May 1988 to March 1990, the bovine internal thoracic artery (ITA) graft, 3 mm in diameter, was used for coronary artery bypass grafting in 29 patients with the approval of the Japanese Ministry of Health. Excluding three postoperative deaths and 6 patients who rejected postoperative angiography, 20 patients (13 men and 7 women; mean age, 62 years; range, 37 to 80 years) were followed up angiographically for up to 4 years. Sites of bovine ITA anastomosis were as follows: anterior descending, 4; circumflex, 5; and right coronary artery, 11. The mean bovine ITA graft blood flow measured by electromagnetic flowmeter was 75.2 mL/min (range, 40 to 150 mL/min). During the mean follow-up of 45 months (range, 30 to 52 months), 12 patients underwent postoperative angiography once, 6 patients twice, and 2 patients three times. It revealed 14 of 16 (88%) bovine ITA grafts were patent within 2 postoperative months. Three of 6 (50%) were patent at 3 to 12 months, of which 2 patent grafts required balloon angioplasty for distal anastomotic stenosis. In 7 patients restudied later than 1 year (20, 24, 25, 44, 48, 50, and 52 months), one of seven grafts (14%) was patent. There was stenosis (> or = 50%) at four distal and one proximal bovine ITA anastomotic sites, but no focal stenosis was found in the trunk at any period. There was one late death due to renal failure, one myocardial infarction, and one mild angina due to bovine ITA graft failure.(ABSTRACT TRUNCATED AT 250 WORDS)

Doppler miniprobe to measure arterial graft flow in coronary artery bypass grafting

Using a 5 X 5-mm ultrasonographic Doppler miniprobe, the flow volume of arterial grafts (internal thoracic artery and gastroepiploic artery) was measured four times during the course of coronary artery bypass grafting. Graft flow just before sternal closure was almost equivalent to that in the preoperative phase when the anastomosis was optimal. Use of the Doppler miniprobe facilitated evaluation of the arterial graft flow pattern easily and quickly. We conclude that the Doppler miniprobe can provide helpful information for the evaluation of results of coronary artery bypass grafting in real time without necessitating any additional procedures.

Percutaneous angioplasty of stenosed gastroepiploic artery grafts

OBJECTIVESnThis report describes our early experience and results with percutaneous transluminal coronary angioplasty of gastroepiploic artery grafts in 12 patients.nnnBACKGROUNDnAngioplasty has been successfully performed in saphenous vein and internal thoracic artery grafts; however, experience with angioplasty in gastroepiploic artery/coronary artery bypass grafts is limited.nnnMETHODSnBalloon angioplasty was performed in 12 patients (11 men, 1 woman; mean age 58 +/- 8 years) with either total occlusion (6 patients) or severe stenosis (6 patients) of a gastroepiploic artery/coronary artery anastomosis. In seven patients, a guide wire/balloon catheter system was used through a 7F sheath inserted into the celiac trunk. In seven patients, including two who had unsuccessful wire/balloon angioplasty, an over the wire system was used through a 6.5F Cobra or 7F JR4 guide catheter, selectively inserted into the gastroduodenal artery.nnnRESULTSnAngioplasty was successful in five (83%) of six patients with stenosis and in one of six patients with total occlusion (p = 0.08, 1 - beta = 0.68). The guide wire could not be advanced through the lesion in five patients, and the balloon catheter did not cross the lesion in one patient whose gastroepiploic artery was tortuous. Catheters exhibited better trackability and pushability when the over the wire system was used, and five of the six successes were achieved using this approach. Follow-up arteriography was performed in five patients, and all of the gastroepiploic artery grafts were patent without stenosis.nnnCONCLUSIONSnAngioplasty can be safely performed in stenosed gastroepiploic artery grafts. An over the wire system that uses a thin balloon catheter inserted through a guide catheter in the gastroduodenal artery seems optimal.

Gastroepiploic artery graft for anterior descending coronary artery bypass

In 308 right gastroepiploic artery (GEA) grafting procedures performed for myocardial revascularization, 38 GEA, 34 in situ, and four free grafts were used to bypass the left anterior descending coronary artery (LAD). Indications for using the GEA for the purpose of LAD bypass were: unavailability of the internal thoracic artery (ITA) at reoperation, surgical damage to the ITA at the time of the operation, or an apparently better free flow versus that in the left ITA, particularly in patients with diabetes mellitus in whom it was considered inadvisable to use bilateral ITAs. There were 21 male and 17 female patients with a mean age of 62 years (range, 31 to 77 years). Ten patients had undergone a previous myocardial revascularization. The mean number of distal anastomoses was 2.8 (range, 1 to 5). Concomitantly used conduits were the ITA in 27 patients, saphenous veins in 21 patients, the inferior epigastric artery in 4 patients, and the bovine internal thoracic artery in 1 patient. All but 1 patient survived. Follow-up ranged from 3 to 84 months (mean, 27 months). Postoperative angiography was performed in 33 patients. At the short-term evaluation (mean, 1 month), 32 of 33 (97%) GEA grafts were found to be patent; all 4 GEA grafts studied at the long-term evaluation (mean, 25 months) were also found to be patent. In no patients did angina recur postoperatively. In 25 patients who underwent an exercise study postoperatively, the stress test results were negative in 23.(ABSTRACT TRUNCATED AT 250 WORDS)

Thrombotic occlusion of the coronary artery associated with accidental detachment of undeployed Palmaz‐Schatz stent

We describe a case of coronary stenting in which accidental detachment of the Palmaz-Schatz stent induced thrombotic occlusion of the coronary artery. This case suggests that careful consideration of the risk involving coronary occlusion is mandatory on deciding the therapeutic strategy of the cases in which the unexpanded coronary stent cannot be retrieved following successful deployment.