Complete myocardial revascularization with bilateral internal thoracic artery T graft

BACKGROUND: The internal thoracic artery is widely recognized as the ideal graft for coronary artery bypass procedures. However, because of the inadequate length of the conduit, use of bilateral internal thoracic artery grafting was not suitable for complete revascularization. To overcome this limitation, the T graft was introduced in the 1990s. We decided to prospectively assess the safety of this technique. METHODS: One hundred six patients with a mean age of 51.5 years underwent complete revascularization with an internal thoracic artery T graft. Mean left ventricular ejection fraction was 0.60 (range, 0.22 to 0.85). RESULTS: No patient required reexploration for bleeding, and no patient died within 30 days after operation. On the basis of electrocardiographic changes, 3 patients sustained a perioperative myocardial infarction. One patient had a sternal wound infection. Mean follow-up was 35 months (range, 15 to 61 months). The actuarial survival rate was 99% +/- 1% at 5 years. No myocardial infarctions were reported during the follow-up. Seven patients had recurrent angina. Eighty patients (76%) underwent postoperative stress tests, and 90% had negative results. CONCLUSIONS: Complete myocardial revascularization with the T graft is a safe and reliable technique with excellent midterm results.     

Right coronary artery revascularization in patients undergoing bilateral internal thoracic artery grafting: comparison of the free internal thoracic artery with saphenous vein grafts

From April 1996 to July 1999, 241 consecutive patients underwent complete arterial revascularization with composite T-graft, including right coronary artery grafting with free right internal thoracic artery (ITA) (ITA group). They were compared with 127 bilateral ITA patients in whom saphenous vein grafts (SVG) was used for grafting the right coronary system (SVG group). The SVG group included more diabetics (40 vs. 29%), more emergency cases (21 vs. 12.4%), and the number of anastomoses per patient was higher (3.8 vs. 3.35, P=0.025). Thirty-day mortality was 3.9 and 4.1% in the SVG and the ITA groups, respectively (P=NS). Occurrence of perioperative complications (sternal infection, myocardial infarction, cerebrovascular accident, and bleeding) was not statistically significant. However, in sum, the complications rate was higher in the ITA group (8.3 vs. 2.4%, P=0.032). Midterm followup (2-56 months) showed increased return of angina in the ITA group (9.1 vs. 1.6%, P=0.00). However, 4-year survival (Kaplan-Meier) was comparable (91.7% in the SVG and 87% in the ITA group). In conclusion, early results of complete arterial revascularization with composite T-graft are similar to those of bilateral ITA grafting of the left and right system revascularization with SVG. However, lower return of angina in the SVG group makes SVG grafting preferable for the right coronary system.     

Right coronary revascularization using the right internal thoracic artery in situ with persisting side branches

There is a controversy about flow steal when the internal thoracic artery is used, with its remnant branches, to revascularize the coronary system. We report a case of a 64-year-old man who was submitted to revascularization using an in situ right internal thoracic artery, with persisting side branches, to supply the right coronary system. Angiography, Doppler echocardiography, and echocardiography at rest and under stress were performed. We found no evidence of flow steal.     

Arterial myocardial revascularization with in situ crossover right internal thoracic artery to left anterior descending artery

BACKGROUND: The extra length obtained by skeletonizing the internal thoracic arteries (ITAs) enables versatile use of in situ bilateral ITAs for coronary artery bypass grafting, as the longer skeletonized right ITA more easily reaches the anastomotic site on the left anterior descending coronary artery. METHODS: Between April 1996 and November 1999, 365 consecutive patients underwent revascularization with bilateral in situ ITAs (29% of 1,250 grafting procedures performed with both ITAs in our department during this period). The right ITA was routed anterior to the aorta to graft the left anterior descending coronary artery, and the in situ left ITA was used to graft circumflex branches. Right coronary artery branches were grafted with right gastroepiploic artery or saphenous vein graft. The right ITA crossed the midline above the aorta at the most cranial point to avoid damage in case of a repeat sternotomy in the future. RESULTS: The operative mortality rate was 2.2% (8 patients). Postoperative morbidity included seven strokes (1.9%), eight sternal wound infections (2.2%), and four perioperative myocardial infarctions (1.1%). Follow-up (6 to 49 months) of 97% of hospital survivors showed a return of angina in 3%. Postoperative coronary angiography (22 patients) revealed a 95% patency rate of both ITAs. One-year and 4-year survival rates (Kaplan-Meier) were 95% and 92.4%, respectively. Important predictors of an early unfavorable event were chronic obstructive pulmonary disease, old age (> or = 70 years), emergency operation, and diabetes. Chronic obstructive pulmonary disease was the only independent predictor of sternal wound infection (odds ratio, 15; 95% confidence interval, 2.8 to 80). It also predicted decreased late survival (hazard ratio, 8.3; 95% confidence interval, 3 to 21.5). CONCLUSIONS: With skeletonized dissection of ITAs, the right ITA easily reaches the left anterior descending coronary artery for left-sided arterial revascularization with in situ bilateral ITAs. This procedure is safe, but we recommend avoiding its use in patients with chronic obstructive pulmonary disease.     

Long-term angiographic evaluation of free internal thoracic artery grafting for myocardial revascularization.

Between 1990 and 1998, 41 patients underwent free internal thoracic artery grafting for coronary artery bypass. To investigate usefulness of free internal thoracic artery grafting, we compared the postoperative graft patency of free internal thoracic artery grafts with that of in situ internal thoracic artery grafts, and compared the long-term results such as actual survival and cardiac-event free rate in patients receiving free internal thoracic artery grafts with those results in patients receiving in situ internal thoracic artery grafts. Postoperative changes in luminal diameter of free internal thoracic artery grafts were calculated as the difference between the first and secondary angiographic evaluation in 17 patients who were followed-up for more than 5 years. The early postoperative graft patency rate of free internal thoracic artery was 95.2%. All these early patent grafts remained patent at the time of the late study. At 9 years post-surgery, patients who received free internal thoracic artery grafts had a survival rate of 100% and a cardiac event-free rate of 77.5%; the luminal diameter enlargement was 0.57 mm, and the mean matching rate increased 27.8%. We conclude that the free internal thoracic artery provides long-term results comparable with those of in situ internal thoracic artery.     

Bilateral internal thoracic artery T grafting for coronary artery revascularization

OBJECTIVES: We studied the early outcome of bilateral internal thoracic artery T grafting. METHODS: Coronary artery bypass grafting was studied retrospectively using bilateral internal thoracic artery T grafting in 51 patients. The T graft was made by anastomosing the free right internal thoracic artery to the in-situ left internal thoracic artery. Average patient age was 63.5 +/- 9.9 years, and the average number of anastomoses per patient was 3.6 +/- 0.9. In 35 patients, the right gastroepiploic artery (21 anastomoses in 20 patients), radial artery (1 anastomosis), free left internal thoracic artery (1 anastomosis) and saphenous vein graft (14 anastomoses in 13 patients) were used as additional bypass conduits. RESULTS: Hospital mortality was 0%. The morbidity of stroke was 1.9% (1 patient) and deep sternal infection 0%. Patency of the in-situ left internal thoracic artery was 49/50 anastomoses (98%) and that of the free right internal thoracic artery 81/84 anastomoses (96.4%). Mid-term coronary angiography in 7 patients demonstrated patent anastomosis of the T graft. Acute myocardial infarction unrelated to graft failure occurred in 2 patients during follow-up. Other patients were evaluated by exercise stress tests every year and none exhibited myocardial ischemia in the areas of T graft coronary revascularization. Three-year actuarial survival rate was 100% and freedom from cardiac events 96%. CONCLUSIONS: The bilateral internal thoracic artery T graft provides satisfactory early and mid-term outcomes in properly selected patients.     

Use of the internal mammary artery in myocardial revascularization

Internal mammary artery-coronary artery anastomosis is currently considered the newest and best technique for surgical revascularization of ischemic myocardium. The origin and evolution of this technique are reviewed.     

Free internal mammary artery graft in myocardial revascularization

Between August 1986 and March 1993, 124 patients (102 men; mean age of 59 years) underwent myocardial revascularization with the use of at least one free internal mammary artery (FIMA). This group represents 4.5% of the 2725 coronary bypasses performed during the same period. Seventy-six patients (61%) had suffered from at least one previous myocardial infarction. Forty-five patients (36%) had unstable angina; three-vessel disease was found in 100 cases (80.5%) and a left ventricular ejection fraction lower than 0.4 in 22 (17.7%). There were 18 (14.5%) redo procedures and 90 (72.5%) bilateral internal mammary artery (IMA) grafts. The reasons for using a FIMA were: too short an internal mammary artery pedicle in 83 patients, IMA injury at harvesting in 30 patients and post-bypass ischaemia in areas grafted with pedicled IMA (PIMA) in 11 patients. Cardiopulmonary bypass, moderate hypothermia (30 °C) and crystalloid anterograde and retrograde cardioplegia were used in all cases. Sixty-seven FIMA grafts were anastomosed directly to the ascending aorta; 57 were sutured via a saphenous hood using a running suture of polypropylene 7/0 and three were anastomosed end-to-end to a PIMA graft. FIMA grafts were directed to the left anterior descending (34%), the circumflex (37%) and the right coronary artery (29%). In total, 179 anastomoses were constructed using 127 FIMA, 136 using PIMA and 158 using saphenous veins (3.8 anastomoses per patient). Hospital mortality and postoperative myocardial infarction rates were 5.6% (seven patients) and 3.2% (four patients), respectively. Cardiac-related mortality was 3.2% (four patients); three of these four patients had been operated on for evolving infarction and one underwent a redo procedure. Four of the 117 survivors died later on; in two, it was cardiac-related and a result of global heart failure at 9 and 12 months. Of the 113 remaining patients, 106 are symptom free after a mean follow-up of 28.2 (range 3–84) months. Fifty-nine patients (50.4%) were restudied by angiography at a mean interval of 15 months. Patency rates of FIMA anastomosed either directly to the aorta or via a saphenous hood were 82.8 or 89.7%, respectively. Patency rates of FIMA directed to the left anterior descending, the circumflex and the right coronary artery were 85.7, 88 and 83.3%, respectively. Global FIMA patency was 86.4%, while global PIMA patency was 100%. The FIMA mid-term patency rates compare unfavourably with those of PIMA: FIMA should therefore be restricted to the cases where PIMA or other pedicled arterial grafts are unavailable.     

Multivessel coronary revascularization with bilateral internal thoracic artery grafts

Sixteen patients underwent coronary revascularization with bilateral internal thoracic artery (ITA) grafts between 1988 and 1989 at the Okayama University Hospital. A total 39 coronary grafts were performed, being an average of 2.4 grafts per patient. Each patient received bilateral ITA grafts, and in 5 patients an additional 7 grafts were constructed with 5 autologous veins and 2 gastroepiloic arteries. The right ITA was grafted as a free graft in 4 patients. The ITA graft patency rate was 96.8 per cent (31/32) at the time of hospital discharge. The postoperative morbidity included one reoperation for bleeding and one myocardial infarction. Coronary artery bypass grafting with bilateral ITA grafts can be safely performed and its application facilitates complete revascularization with arterial grafts.     

Coronary revascularization with bilateral internal thoracic artery grafts]

Thirty-two patients underwent coronary revascularization with bilateral internal thoracic artery (ITA) grafts. Each patient received 2.7 grafts in average including double ITA grafts. Seventeen patients had the right ITAs as free grafts. The other sixteen were treated with 13 autologous veins and 9 right gastroepiploic arteries in addition. Fifty-five grafts out of 56 (98.2%) were proved to be patent at the time of hospital discharge. The postoperative morbidity included three reoperations for bleeding and one perioperative inferior myocardial infarction. One patient died of colon perforation after surgery and another died of cerebral infarction late after surgery. These results exhibited that coronary artery bypass grafting with bilateral ITA grafts had relatively low risks and could contribute to complete revascularization in patients with diseased coronary arteries.     

Reoperation for myocardial revascularization using the internal mammary artery

From October 1984 up to February 1989, 40 patients had "redo" myocardial revascularizations using one or both internal mammary arteries (IMA) in over 1000 cases operated upon in our Department for coronary bypass grafts. Thirty-one patients had a further operation for unstable angina difficult to control with drugs. Mean interval of recurrence of angina after previous surgery was 48.5 months for all the cases, but the mean interval before the second bypass operation was 68 months. Severe disease of previous vein grafts was the reason for surgery in 25 patients and progressive atherosclerosis in native coronary arteries in 15 patients. Twenty-one patients had a single mammary artery; both mammary arteries were used in 19. Two cases had endarterectomy on left anterior descending (LAD). Four patients had peroperative acute myocardial infarction (AMI), 3 a low cardiac output syndrome, postoperative bleeding occurred in 3 cases and wound infection in one case. An intraaortic balloon pump was used preoperatively in one case and coming off bypass in two others. One patient died on the second day postoperatively from cardiac arrest following bilateral pneumothorax. There were no late deaths. At a mean follow-up of 20.5 months, 28 patients are free of symptoms but 11 are complaining of angina, 5 during exercise and 6 at rest. An exercise test was positive in 8 patients.     

Long-term follow-up of total arterial myocardial revascularization using exclusively pedicle bilateral internal thoracic artery and right gastroepiploic artery

Objective: In order to reduce remote cardiac events associated with graft occlusions, arterial conduits are being increasingly utilized in coronary artery bypass grafting (CABG). While the internal thoracic artery (ITA) is the graft of choice for CABG, it is sometimes difficult or impossible to obtain a complete arterial revascularization only with ITAs in three-vessel diseases. We present our experience with total arterial myocardial revascularization with bilateral internal thoracic artery (BITA) and right gastroepiploic artery (rGEA). Methods: From April 1994 to January 2004, 174 patients (165 male, mean age 55.9±7.4) underwent coronary artery bypass procedure with exclusive use of BITA and rGEA. Left ventricular ejection fraction ranged from 20 to 68% (mean 55.9±6.8%). Seven patients (4%) had poor ejection fraction (<0.30), 23 (13, 2%) had acute myocardial infarction, 14 (8%) had left main disease. The mean CPB time was 96.9±15.7 min and the mean cross clamping time was 70±14.2 min. The mean number of distal anastomoses was 3.3±0.5 per patient. Results: Early mortality was 1.7%. The patients were followed for up to 9 years (mean follow-up time 6.3±2.6 years). Actuarial freedom from cardiac death (including hospital death) was 97.6%, at 9 years after the operation. Actuarial freedom from angina and cardiac events at 9 years was 79, 5% and 77, 6%, respectively. No perioperative myocardial infarction occurred. None of the patients needed a redo-CABG after leaving the hospital. Conclusions: This study indicates that the myocardial revascularization in young patients with three-vessel disease using exclusively pedicle BITA and rGEA provides excellent 9-year patient survival and improvement in terms of freedom from return of angina pectoris and freedom from any cardiac-related event. These results encourage the more extensive use of BITA and rGEA in selected patients with three-vessel coronary disease.