Bilateral internal thoracic artery grafting: long-term clinical and angiographic results of in situ versus Y grafts

BACKGROUND: We evaluated whether bilateral internal thoracic arteries provide the same long-term results when used as in situ grafts and as Y grafts.Methods and Results: From October 1991 to February 2000, 1818 patients had bilateral internal thoracic arteries used as in situ (n = 1378, group A) or as Y grafts (n = 440, group B). The number of anastomoses per patient and the number of bilateral internal thoracic artery anastomoses per patient were higher in group B (3.1 +/- 0.9 and 2.7 +/- 0.9) than in group A (2.9 +/- 0.8 and 2.2 +/- 0.6) (both P <.001). The number of right internal thoracic artery anastomoses per patient rose from 1.0 +/- 0. 3 in group A to 1.4 +/- 0.6 in group B (P <.001), and the number of sequential anastomoses per right internal thoracic artery graft rose from 4.1% to 34.3% (P <.001). Thirty-day mortality was 2.0% in group A versus 2.5% in group B (P = not significant). No difference in postoperative course was detected. Eight-year survivals were 95.8% +/- 2.7% in group A versus 94.8% +/- 4.0% in group B (P = not significant), and event-free survivals were 95.2% +/- 2.9% in group A versus 93.6% +/- 4.4% in group B (P = not significant). Early angiograms were obtained in 295 patients (945 anastomoses, 863 distal and 82 proximal Y grafts), 213 patients (611) in group A and 82 patients (334) in group B. Patency rate was 98.8% in group A and 96.0% in group B (P = not significant), whereas grade A patency rate was 97.2% in group A and 96.4% in group B (P = not significant). Late angiograms were obtained in 88 patients (25 in group A and 63 in group B) at a mean of 17.5 +/- 18.4 months: patency rate was 100% in group A and 99.2 in group B (P = not significant), and grade A patency rate was 98.6% in group A and 98.8% in group B (P = not significant). No Y anastomosis was occluded or stenosed. COMMENT: Survival, incidence of cardiac events, and angiographic patency in the early and late phases are similar for bilateral internal thoracic arteries used either in situ or as Y grafts. However, Y grafting with bilateral internal thoracic arteries increases the number of anastomoses per bilateral thoracic artery, as well as the flexibility of the right internal thoracic artery.     

Left internal thoracic artery composite grafting with the right internal thoracic versus radial artery in coronary artery bypass grafting

Abstract Background: The aim of this study was to compare the results of all arterial multivessel coronary artery bypass grafting using the left internal thoracic artery composite bypass graft constructed with the right internal thoracic artery or radial artery. Methods: Patients undergoing coronary artery bypass grafting with a left internal thoracic artery constructed as a composite bypass graft with either a right internal thoracic artery (n = 45; RITA group) or radial artery (n = 352; RA group) between 2003 and 2009 were included in the present study. Results: The three‐year patency rates for the RITA and RA groups were 91.8%± 4.3% and 78.6%± 3.4%, respectively (p = 0.12). Adjustments for covariates revealed the radial artery patency to be significantly inferior to the right internal thoracic artery graft (hazard ratio 4.35, 95% confidence interval 1.05 to 18.0; p = 0.043). Reintervention for target coronary artery occlusion was required in two patients in the RA group over a mean follow‐up period of 35.5 ± 21.5 months. There were 43 deaths in the entire cohort of which 20 were cardiac. After adjustment for significant variables, the risk of all‐cause mortality, cardiac death, and the composite of adverse events (death, reintervention, myocardial infarction, and stroke) were similar for the two groups (p = 0.98, 0.99, and 0.21, respectively). Conclusions: Although superior patency was observed with the right internal thoracic artery over the radial artery graft, a significant commensurate benefit in reducing the incidence of major adverse clinical outcomes was not necessarily shown. (J Card Surg 2011;26:579‐585)     

Skeletonized radial artery grafting: improved angiographic results

Background. The radial artery has been used for coronary artery bypass grafting (CABG) but its early angiographic results were relatively inferior to that of the internal mammary artery, most likely due to spasm of the graft. To avoid vasospasm we harvested the radial artery using a skeletonized technique and spasm was completely reversed before use. The graft patency of the skeletonized radial artery was compared with the radial artery graft harvested as a pedicle.

Methods. A total of 112 patients underwent isolated CABG using a pedicled radial artery between September 1, 1999, and August 31, 2000 (group P), and a total of 131 patients with a skeletonized radial artery between September 1, 2000, and August 31, 2001 (group S). An ultrasonic scalpel (Harmonic Scalpel; Ethicon Endo-Surgery, Cincinnati, OH) was used for skeletonization and removing satellite veins and surrounding tissue. CABG was performed by the standard technique. Perioperative results were prospectively collected and compared between the two groups. Early angiographic results performed within 3 months were also compared.

Results. There were two hospital deaths in group S. Major complications were observed in 11 (8.4%) in group S and 3 (2.7%) in group P (p = not significant [NS]). None were related to the radial artery graft. Angiography was obtained in 96 patients of group S and 76 patients in group P and revealed that the stenosis free graft patency rate of group S (138 of 143, 96.5%) was superior to that of group P (73 of 86, 84.9%) with p < 0.005.

Conclusions. Skeletonization of the radial artery with the ultrasonic scalpel is safe and contributes to reducing the incidence of early graft stenosis.     

T grafts with the right internal thoracic artery to left internal thoracic artery versus the left internal thoracic artery and radial artery: flow dynamics in the internal thoracic artery main stem.

OBJECTIVE: Complete arterial coronary artery bypass grafting with 2 grafts can be achieved even in triple vessel disease by use of a T configuration. There is still uncertainty whether the coronary flow reserve in the main stem of the left internal thoracic artery is sufficient to supply more than 1 anastomosed coronary vessel. METHODS: Between March 1996 and February 1999, 251 patients with multivessel coronary artery disease underwent complete arterial revascularization with T grafts, using either the left internal thoracic artery with the free right internal thoracic artery graft (n = 73, group I) or the left internal thoracic artery and radial artery (n = 178, group II). A mean of 4.0 (group I) versus 4.3 (group II) coronary vessels were anastomosed per patient. One week (n = 92) and 6 months (n = 28) after the operation, flow was measured in the proximal left internal thoracic artery with a Doppler guide wire. Maximum flow was determined after injection of adenosine (30 microg). RESULTS: The in-hospital mortality was 2.7% (group I) versus 2.3% (group II). At angiography (n = 142, 56.6%) the patency rate was 96.3% (group I) versus 98.2% (group II). There was no significant difference between baseline flow, maximum flow, and coronary flow reserve between the 2 groups. Coronary flow reserve increased in both groups within the first 6 postoperative months (group I, 1.85 +/- 0.31 vs 2.77 +/- 0.77, P =.0002; group II, 1.82 +/- 0.4 vs 2.53 +/- 0.73, P =.009). CONCLUSION: Both variants of T grafts allow for complete arterial revascularization with good perioperative results. The flow reserve of the proximal internal thoracic artery is adequate for multiple coronary anastomoses irrespective of the choice of the second arterial graft.     

Comparison of long-term clinical results of double versus single internal mammary artery bypass grafting

BACKGROUND: The long-term benefits of double versus single internal mammary artery (IMA) coronary bypass grafting have not yet been established. METHODS: Six hundred patients were studied retrospectively 10 years after coronary revascularization using saphenous vein grafts (SVGs) only or single or double IMA grafts. RESULTS: Patients with double IMA grafts were younger and were more likely to have diabetes, left main coronary stenosis, and three-vessel coronary artery disease than patients with SVGs or single IMA grafts. Patients with SVGs and double IMA grafts had a greater number of diseased coronary vessels and a greater number of coronary bypass grafts per patient than patients with single IMA grafts (mean +/- SEM, 2.8 +/- 1.0, 2.8 +/- 0.7, 2.1 +/- 0.8 grafts per patient, respectively, p < 0.0001). Actuarial survival rates 10 years after placement of SVGs and single and double IMA grafts averaged 83% +/- 6%, 90% +/- 4%, and 87% +/- 8%, respectively (p = 0.03). Cox regression analysis showed that diabetes (relative risk, 2.03; 95% confidence interval, 1.55 to 2.66) and chronic pulmonary obstructive disease (relative risk, 2.20; 95% confidence interval, 1.58 to 3.80) increased, whereas an IMA graft on the left anterior descending coronary artery significantly decreased, the risk of death after operation (relative risk, 0.45; 95% confidence interval, 0.36 to 0.57) throughout the follow-up period. CONCLUSIONS: Use of an IMA graft on the left anterior descending coronary artery improves survival compared with use of an SVG. Although patients with double IMA grafts had a greater number of poor prognosis risk factors before operation, their 10-year survival rate was similar to that of patients with a single IMA graft.     

In situ right internal thoracic artery graft for revascularization of circumflex artery. Early results and long-term angiographic follow up.

In 285 patients, the right internal thoracic artery, routed through the transverse sinus, was in most cases anastomosed to the circumflex branches. In 278 cases, the left internal thoracic artery was simultaneously used for revascularization of the left anterior descending artery. Two patients died (mortality rate 0.7%). Postoperative early angiography on 278 patients revealed a high graft patency of 97.8% for the right internal thoracic artery and 96.9% for the left internal thoracic artery. A long-term follow-up study was performed on the first consecutive 115 patients who survived the operation. Seven patients died, 2 due to cardiac causes. Angiographic assessment was performed in 73 patients (67%) at an interval of 28.8 to 93.1 months (mean 58.9 months). Five right internal thoracic arteries were occluded and sledlike right internal thoracic artery grafts were present in 2 patients. Two of them had been confirmed in the previous early study to be not patent. Insufficient data was obtained in 4 patients. The perfect patency rate of the right internal thoracic artery was 89.9% (62/69). Five left internal thoracic arteries were occluded, providing a perfect patency rate of 92.3%. There was no significant difference between the success rate using the right internal thoracic artery and that resulting from using the left internal thoracic artery. We conclude that coronary revascularization using this technique provides good clinical results and excellent early and late patency of the right internal thoracic artery.     

Long-term results of bilateral internal thoracic artery grafting

Background. Little is known about the long-term results of the uniform group of patients who had bilateral internal thoracic artery (ITA) grafting with the method of left ITA-to-left anterior descending coronary artery and right ITA-to-circumflex artery.

Methods. Late follow-up study was performed in the first consecutive 203 patients (mean age, 62.6 ± 9.1 years) who underwent isolated coronary artery bypass grafting with the left ITA anastomosed to the left anterior descending coronary artery and the right ITA to major branches of the circumflex artery. The patients were grouped according to the patency of ITA grafts demonstrated by early postoperative angiography (Both patent (BP) group, 168 patients: both ITAs showed complete patency; Not patent (NP) group, 23 patients: at least one ITA was dysfunctional).

Results. Actuarial 7-year survival in all patients was 89.3% ± 3.1%. The cumulative probability of event-free survival for cardiac death, myocardial infarction, intervention, and angina at 7 years was 96.6% ± 1.8%, 98.0% ± 1.5%, 86.7% ± 3.2%, and 90.7% ± 2.9%, respectively. NP group had more myocardial infarction and angina than the BP group, but was not statistically significant. Because of failed grafts at the early angiography, intervention was performed more frequently in NP group (p < 0.01).

Conclusions. Our results of actuarial 7-year survival and the cumulative probability of event-free survival were at least comparable to the results of other similar studies using bilateral ITA. The freedom from angina appeared to be better than in the previous study. Overall our study supports the continued use of this method of ITA grafting.     

Off-pump coronary artery bypass grafting using in-situ right internal thoracic artery extended with radial artery as I-composite graft

OBJECTIVE: The purpose of this study is to assess the feasibility of utilizing the proximal right internal thoracic artery (RITA) extended with the radial artery (RA) as I-composite graft (RITA-RA graft) in off-pump coronary artery bypass grafting (OPCAB), which preserves the left internal thoracic artery to the left anterior descending artery as an isolated graft and the ascending aorta no-touch technique. METHODS: Between January 2002 and August 2006, 37 patients (aged 67.4+/-7.5 years, 86.5% male) underwent OPCAB using RITA-RA graft. All grafts were harvested in a skeletonized fashion. RITA transected at the middle portion was extended with entirely dissected RA. RITA-RA graft was anastomosed to 1 or 2 lateral artery in a parallel sequential pattern. RESULTS: The total number of distal anastomoses of RITA-RA graft was 48. The early graft patency rate was 97.9%. Five cases (13.5%) needed intra-aortic balloon pumping support during operation. Only 1 patient (2.7%) required ventilator support longer than 24 hours. The percentage of patients requiring homologous blood transfusion was 13.5%. There was no cerebrovascular accident or mediastinitis in the postoperative course. All patients were discharged from hospital. CONCLUSIONS: OPCAB using RITA-RA graft is feasible and safe. It provides satisfactory early clinical and angiographic outcomes.     

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.     

Bilateral internal thoracic artery grafting: midterm results of composite versus in situ crossover graft

BACKGROUND: Two common techniques of bilateral internal thoracic artery grafting are the composite T graft and in situ crossover graft. The superiority of one method over the other has not yet been established. METHODS: From April 1996 to July 1999, bilateral skeletonized internal thoracic arteries were used as T grafts (composite group, n = 649) and in situ grafts (cross group, n = 351) in 1,000 consecutive patients. In the cross group, in situ right internal thoracic artery was routed anterior to the aorta across the midline for grafting to the left anterior descending artery, and the left internal thoracic artery was used for the circumflex branches. RESULTS: The two groups had comparable preoperative risk profiles. Bypass time and aortic cross-clamping time were longer in the composite group (80 +/- 38 and 67 +/- 29 minutes versus 66 +/- 43 and 55 +/- 34 minutes, respectively). Number of anastomoses per patient was similar (3.1 versus 3.2). However, more sequential anastomoses were performed in the composite group (62% versus 53%), and the gastroepiploic artery was used more often in the cross group (30% versus 19%). Thirty-day mortality was 3.9% in the composite and 2.3% in the cross group (not significant). Occurrence of postoperative complications (sternal infection, myocardial infarction, cerebrovascular accident, and bleeding) was similar. Late follow-up (2 to 56 months) showed increased return of angina (6% versus 3.1%; p = 0.046) and decreased 4-year survival (Kaplan-Meier; 86% +/- 2.7% versus 92.4% +/- 1.5%; p = 0.07) in composite patients. CONCLUSIONS: Early results of bilateral internal thoracic artery grafting with composite T graft are comparable with those of in situ grafts. However, increased angina return and decreased midterm survival led us to recommend in situ grafting whenever technically possible.     

Early clinical and angiographic outcome of the pedicled right internal thoracic artery graft to the left anterior descending artery

BACKGROUND: The left internal thoracic artery (LITA) graft to the left anterior descending (LAD) artery became the gold standard graft in coronary surgery. Subsequently, the right internal thoracic artery (RITA) graft was increasingly used. However, there is still some debate about the optimal way of using this conduit. The aim of the present study was to assess our experience in grafting the pedicled RITA graft to LAD in 212 consecutive patients. METHODS: The records of 212 consecutive patients who underwent isolated coronary artery bypass grafting with the pedicled RITA graft to the LAD artery at Harefield Hospital between January 1998 and May 2001 were retrospectively reviewed. We approached the last 35 consecutive patients to obtain an angiographic control group. All 35 patients (16.5%) consented and, before discharge, underwent angiography to look at the quality of anastomoses and the patency of grafts. RESULTS: Successful catheterization and engagement of the RITA grafts was performed in 32 patients. Angiography showed that 32/32 (100%) of the RITA grafts were widely patent with excellent flow. The distal anastomoses of these RITA grafts were also satisfactory. There were no deaths among the study patients. CONCLUSIONS: Our results show that the use of the pedicled RITA graft to the LAD artery provides a good early clinical and angiographic outcome, and suggests that the pedicled RITA graft to the LAD artery is a good alternative to the pedicled LITA graft to the LAD artery.     

Differential in vitro response of the human radial artery versus left internal thoracic artery to cerivastatin: implications to bypass grafting

BACKGROUND: This study investigated acute (in vitro) and long-term (in vivo) effects of statins on the vascular function of human radial artery (RA) and left internal thoracic artery (LITA). METHODS: RA and LITA specimens were divided into vascular rings, which were incubated in the absence or presence of 10(-6) mol/L Cerivastatin for 2 or 24 hours. In terms of preoperative statin treatment, four groups included: group 1 [preop statin(-)/in vitro cerivastatin(-)]; group 2 [preop(-)/in vitro(+)]; group 3 [preop(+)/in vitro(-)]; and group 4 [preop(+)/in vitro(+)]. Endothelial function was assessed with acetylcholine (10(-9) to 10(-5) mol/L) following contraction by 3 x 10(-8) mol/L endothelin-1. RESULTS: Although endothelium-dependent vasodilatation was higher in RA (57.7% +/- 3.5%) than in LITA (46.5% +/- 3.8%, p = 0.046), there was no significant evidence that it depended on the preoperative use of statins or incubation period. In vitro incubation with cerivastatin significantly increased endothelium-dependent vasodilatation by 14.2% +/- 2.4% (p < 0.0001) independent of artery types (RA/LITA). There was no significant evidence that endothelium-dependent vasodilatation depended on the preoperative use of statins or incubation period. CONCLUSIONS: In vitro incubation with cerivastatin preserved endothelial function more effectively than preoperative use of statins. This could have implications to perioperative use of statins for patients undergoing coronary surgery.