Decreased sternal vascularity after internal thoracic artery harvesting resolves with time: an assessment with single photon emission computed tomography

OBJECTIVE: We sought to prospectively evaluate the long-term effect of left internal thoracic artery harvesting on sternal vascularity. METHODS: Twelve consecutive patients undergoing primary coronary artery bypass grafting were studied. In all patients a pedicled left internal thoracic artery was harvested. Each patient underwent a preoperative technetium-99m methylene diphosphonate bone scan with single photon emission computed tomography. The ratio of the mean counts per pixel for each side of the sternum was obtained. All patients had early repeat bone scans 6 plus minus 2.4 days postoperatively and late repeat bone scans 18.6 plus minus 3.5 months after the operation. Ratios of unilateral sternal uptakes were compared between the different scans. One patient died during follow-up and was excluded from the study. RESULTS: There was a significant decrease in flow to the left hemisternum in the early postoperative scan compared with that in the preoperative scan (P <.001). At late follow-up scans, flow to the left hemisternum had returned to normal (P =.119). Midterm clinical follow-up demonstrated 3 superficial wound infections. No musculoskeletal pain existed at the time of follow-up, but 3 patients had numbness or tingling at the skin area corresponding to the site from which the left internal thoracic artery was harvested. CONCLUSIONS: Acute postoperative sternal ischemia caused by harvesting of a pedicled left internal thoracic artery is temporary and resolves with time.     

Skeletonization of bilateral internal thoracic artery grafts lowers the risk of sternal infection in patients with diabetes

OBJECTIVE: Deep sternal wound infection is a dreaded complication of coronary artery bypass surgery, particularly in patients with diabetes. This study determines whether skeletonization of internal thoracic artery conduits compared with pedicled harvesting reduces the risk of deep sternal wound infection in patients with diabetes undergoing bilateral internal thoracic artery grafting. METHODS: We reviewed prospectively gathered data on all patients who have undergone coronary artery bypass grafting and received bilateral internal thoracic artery grafts at our institution since 1990. We compared patients with diabetes who received skeletonized (n = 79) versus conventional pedicled (n = 36) internal thoracic artery conduits. RESULTS: The proportion of patients taking insulin (19.0% vs 14.0% for skeletonized vs conventional grafts, respectively, P =.6) or oral hypoglycemic agents (68.4% vs 69.4%, P =.9), as well as the prevalence of type I diabetes (2.5% vs 8.3%, P =.18), were similar in both groups. Patients who received skeletonized grafts were more likely to receive a free rather than an in situ right internal thoracic artery graft (93.7% vs 30.6%, P <.001). The prevalence of deep sternal wound infection was significantly lower in patients who received skeletonized grafts compared with patients who received conventional grafts (1.3% vs 11.1%, P =.03). Patients in the skeletonized group were also less likely to develop any (superficial or deep) sternal wound infection postoperatively (5.1% vs 22.2%, P =.03). There was no significant difference in the prevalence of deep sternal wound infection between patients with diabetes who received skeletonized internal thoracic arteries and patients without diabetes who underwent conventional internal thoracic artery grafting (n = 578) (1.2% vs 1.6%, respectively, P =.8). CONCLUSIONS: Skeletonization of internal thoracic artery conduits lowers the risk of deep sternal wound infection in patients with diabetes undergoing bilateral internal thoracic artery grafting. We no longer consider diabetes a contraindication to bilateral internal thoracic artery grafting, provided the internal thoracic arteries are skeletonized.     

The effect of bilateral internal thoracic artery harvesting on superficial and deep sternal infection: The role of skeletonization

OBJECTIVE: To determine the relative risk of sternal dehiscence in patients undergoing bilateral internal thoracic artery harvesting and to assess whether and to what extent the technique of artery skeletonization might reduce this risk. METHODS: Prospectively collected data on patients undergoing coronary artery bypass operations with at least a single internal thoracic artery were reviewed. The last 450 patients receiving bilateral internal thoracic artery grafts were compared with 450 patients who received a single internal thoracic artery during the same period. The left internal thoracic artery was always harvested in a pedicled fashion. Among patients receiving a bilateral internal thoracic artery, both arteries were harvested in a pedicled fashion in 300 cases, whereas both internal thoracic arteries were skeletonized in the remaining 150 cases. RESULTS: Compared with a single internal thoracic artery, harvesting both internal thoracic arteries either in a skeletonized or in a pedicled fashion increased the chance of deep (1.1% vs 3.3% vs 4.7%; P = .01) or superficial (4.8% vs 7.8% vs 12%; P = .002) sternal infection. However, the technique of artery harvesting (odds ratio, 4.1; 95% confidence interval, 1.4-12.1); the presence of peripheral arteriopathy (odds ratio, 3.1; 95% confidence interval, 1.2-8.5), and resternotomy for bleeding (odds ratio, 8.2; 95% confidence interval, 2.0-33.6) were the only independent predictors for deep sternal infection, whereas the technique of artery harvesting (odds ratio, 3.0; 95% confidence interval, 1.6-5.4), female sex (odds ratio, 2.2; 95% confidence interval, 1.2-4.2), and diabetes (odds ratio, 1.7; 95% confidence interval, 1.0-2.9) were the only independent predictors of superficial sternal infection. In diabetic patients, there was no difference in the incidence of deep sternal infection among patients receiving a single internal thoracic artery or double skeletonized internal thoracic arteries ( P = .4). CONCLUSIONS: Bilateral internal thoracic artery harvesting carries a higher risk of sternal infection than harvesting a single internal thoracic artery. Skeletonization of both internal thoracic arteries significantly decreases this risk. A strategy of bilateral thoracic artery grafting can also be offered to patients at high risk for wound infection.     

Early vasoreactive profile of skeletonized versus pedicled internal thoracic artery grafts

BACKGROUND: No data are available on the early vasoreactive profile of skeletonized internal thoracic artery grafts. METHODS: Fifteen patients undergoing primary isolated coronary artery bypass grafting were randomly assigned to receive a skeletonized or pedicled internal thoracic artery graft. On the second postoperative day all patients were subjected to follow-up angiography and endovascular infusion of serotonin, acetylcholine, and isosorbide dinitrate. RESULTS: Internal thoracic artery grafts were widely patent in all cases. Mean diameters of the internal thoracic artery were 1.95 +/- 0.17 mm in the pedicled group and 2.26 +/- 0.40 mm in the skeletonized group. After serotonin challenge, mean internal thoracic artery diameters were reduced to 1.44 +/- 0.34 mm and 1.64 +/- 0.14 mm, respectively; acetylcholine challenge lead to a moderate degree of vasoconstriction (1.55 +/- 0.59 mm in the pedicled group and 1.84 +/- 0.15 mm in the skeletonized group). No statistically significant difference was evident between the two groups at any step. CONCLUSION: Skeletonization does not affect the early vasoreactive profile of internal thoracic artery grafts used for surgical myocardial revascularization.     

Internal thoracic artery: to skeletonize or not to skeletonize?

The internal thoracic artery has been the most reliable graft material used in coronary artery bypass grafting with an excellent long-term patency rate. Complete myocardial revascularization with internal thoracic arteries improves long-term survival and decreases the rate of repeat operations compared with vein grafts. Adequate length of the graft in coronary artery bypass graft surgery is essential for providing complete arterial revascularization. In the last decade or so, technique of skeletonization of internal thoracic artery has been proposed to achieve extra length. Skeletonization of the internal thoracic artery allows the preparation of longer conduits with a superior free flow and can reduce the incidence of postoperative pulmonary and sternal complications. However, concerns about vasoreactivity of skeletonized internal thoracic artery grafts, the functional consequences of surgical trauma, the possible loss of innervation, and vasa vasorum perfusion in the skeletonized conduits have prevented this technique from being universally accepted. Presently available evidence from retrospective studies (level 3 evidence) suggests that skeletonization is a safe and effective technique for myocardial revascularization. However, there is a need for conducting multicenter, randomized controlled trials comparing the skeletonized and pedicled internal thoracic arteries with special emphasis on long-term patency to conclusively validate the safety and efficacy of skeletonization technique.     

Skeletonization does not influence internal thoracic artery innervation

BACKGROUND: This study was designed to compare the effect of surgical harvesting on internal thoracic artery innervation and to assess the eventual presence of denervation supersensitivity in skeletonized grafts. METHODS: Nineteen patients who underwent primary isolated coronary artery bypass grafting were randomly assigned to receive a skeletonized (n = 9) or pedicled (n = 10) internal thoracic artery graft. Immunohistochemical nerve localization using anti-S-100 protein, anti-160-kd neurofilament polypeptide and anti-tyrosine hydroxylase antibodies was performed on distal specimens of arteries to study vascular innervation. Moreover, endovascular vasoactive challenges using serotonin and methylergometrine were performed at early angiographic control to evaluate the eventual presence of denervation supersensitivity. RESULTS: Quantitative analysis of immunohistochemical specimens revealed lack of difference in the number of positive cells between skeletonized and pedicled arteries for all the antibodies used. No difference in the reaction to serotonin and methylergometrine was found between skeletonized and pedicled arteries. CONCLUSIONS: Skeletonization does not influence internal thoracic artery innervation.     

Changing pattern in beating heart operations: use of skeletonized internal thoracic artery

BACKGROUND: The use of skeletonized internal thoracic artery (ITA) was reported to be technically and hemodynamically beneficial in conventional coronary artery bypass grafting with cardiopulmonary bypass assistance. The purpose of this study is to evaluate the impact of changing from conventional to skeletonized ITA harvesting on early off-pump coronary artery bypass grafting outcome. METHODS: Between 1996 and 2001, 640 patients underwent systematic off-pump coronary artery bypass grafting (single surgeon experience). The ITA was pedicled (P) in the first consecutive 440 patients and skeletonized (S) in the subsequent 200 consecutive patients. Mean age, preoperative risk factors, sex, number of involved territories, and incidence of reoperations were similar in both groups. RESULTS: In group S, number of ITAs per patient (1.7 +/- 0.08 versus 1.2 +/- 0.05; p < 0.001), bilateral ITA (46% versus 27%; p < 0.001), ITA sequential grafts (27% versus 1%; p < 0.001), and T grafts (16% versus 3%; p < 0.001) were higher. Deep sternal infections were comparable in both groups (group S: 1%, group P: 1.2%; p = 0.38). Perioperative myocardial infarction, maximal creatinine kinase-MB level, and requirement for more than 24 hours of inotropic support were comparable in both groups. Thirty-day mortality was also similar (S: 1.7%, P: 1.6%). CONCLUSIONS: Changing to routine use of skeletonized ITA in off-pump coronary artery bypass grafting is a safe alternative to routine pedicled ITA. In our experience, this procedure has facilitated the use of ITA anastomosis without increasing sternal wound complications.     

Bilateral skeletonized internal thoracic artery grafts in patients with diabetes mellitus

OBJECTIVE: Increased risk of deep sternal infections has prohibited routine bilateral internal thoracic artery grafting in diabetic patients. The technique for harvesting the skeletonized internal thoracic artery provides the potential to minimize this risk. The purpose of this study was to compare the outcome of bypass grafting with bilateral skeletonized internal thoracic arteries in diabetic and nondiabetic patients. METHODS: From May 1996 to April 1998, 231 consecutive diabetic and 534 nondiabetic patients underwent bilateral skeletonized internal thoracic artery grafting. Mean age was 66 years. Compared with the nondiabetic group, the diabetic group comprised more women (29% vs 18%, P =.001), had a greater prevalence of hypertension (53% vs 44%, P =.019) and congestive heart failure (20% vs 14%, P =.016), but a lower prevalence of preoperative acute myocardial infarction (26% vs 34%, P =.027). RESULTS: Operative mortality of diabetic patients was comparable with that of nondiabetic patients (3% vs 2.6%). The two groups also had similar occurrences of deep sternal infection (2.6% vs 1.7%, respectively, P =.40). Deep sternal infection was significantly more prevalent in obese, diabetic women (3/20 = 15%) than in diabetic patients without this combination of risk factors (3/211 = 1.4%, P <.0001) (odds ratio 11.1, confidence interval 2.1-59.4). Diabetic patients also had a higher incidence of stroke (3.5% vs 0.9%, P =.014). Three-year actuarial survival of diabetic patients was lower (91.3% vs 94.7%, P =.083). CONCLUSIONS: Bilateral skeletonized internal thoracic artery grafting is a good surgical revascularization option in diabetic patients. Operative mortality and prevalence of sternal infection are comparable with those of nondiabetic patients. However, the risk of sternal infection in obese diabetic women is high, and for them we advocate the use of a single artery instead of bilateral internal thoracic arteries.     

Free flow capacity of skeletonized versus pedicled internal thoracic artery grafts in coronary artery bypass grafts.

OBJECTIVE: The internal thoracic artery (ITA) is the ideal conduit for coronary artery bypass grafting (CABG). The skeletonization technique of this arterial conduit has been proposed to reduce chest wall trauma, increase graft length and facilitate construction of sequential anastomoses. Nevertheless, some surgeons decline this technique because of potentially increased trauma to the ITA with impairment of flow. In this investigation we compared the free flow of skeletonized with that of pedicled ITA grafts. METHODS: Two surgeons operated on 80 consecutive patients with coronary artery disease for elective CABG. In group I (n = 40), the left ITA was dissected using the skeletonization technique. In group II (n = 40), it was harvested as a pedicled graft. In 23 patients of group I both ITA's were dissected in skeletonized fashion for complete arterial revascularization. Diluted papaverine was instilled into the lumen of the ITA after distal transection of the vessel in both groups. Free flow of the ITA was registered before and 15 min after intraluminal application of diluted papaverine. Mean arterial pressure was maintained at 70 mmHg. RESULTS: Before the application of papaverine, free flow of skeletonized and pedicled ITA grafts was identical between the two groups. After treatment with papaverine maximum free flow was significantly higher in the skeletonized ITA's (group I 197.2 (+/-66.6) ml/min; group II 147.1 (+/-70.5) ml/min; P < 0.05). There was no significant difference between free flow after dilatation of the left and right ITA in group I (left 197.2 (+/-66.6) ml/min; right 198.9 (+/-61.8) ml/min). CONCLUSIONS: Preparation of the ITA with the skeletonization technique results in significantly, higher free flow capacity than in pedicled grafts. This may increase the safety of arterial revascularization by reducing the risk of ITA hypoperfusion syndrome.     

The effects of different techniques of internal mammary artery harvesting on sternal blood flow.

We investigated chest wall blood flow in a canine model to determine if the technique used to harvest the mammary artery has a differential effect on residual chest wall blood flow. Eight dogs underwent bilateral internal mammary artery mobilization; one artery was harvested as a pedicle and the other was harvested as a skeletonized vessel. Residual blood flow to the chest wall distribution of each artery was measured with radioactive microspheres. Chest wall blood flow was significantly decreased from preharvest levels after internal mammary artery mobilization regardless of the technique used. Tissue blood flows decreased to 46.9%, 22.1%, and 41.2% of baseline values for the manubrium (p < 0.01), sternum (p < 0.001), and ribs (p < 0.05), respectively. Residual sternal blood flow on the side of the skeletonized vessel was significantly greater than on the side of the pedicle graft (2.60 +/- 0.68 versus 1.27 +/- 0.27 cm3/min/100 gm, p < 0.001). We conclude that minimization of tissue mobilization during internal mammary artery harvesting may reduce sternal devascularization. This finding may have clinical significance with respect to lowering the incidence of sternal wound complications in coronary bypass surgery using the internal mammary artery as a bypass conduit.     

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.     

Pitfalls of skeletonized internal thoracic artery: comparison of graft kinking between skeletonized and pedicled grafts based on postoperative angiography findings

BACKGROUND AND AIM OF THE STUDY: Skeletonization of the internal thoracic artery (ITA) has several advantages: sequential bypass grafting can be easily performed, and a graft of increased length can make the distal coronary artery accessible. However, kinking of the grafts has been observed on postoperative angiograms in a few cases. We investigated whether there were significant differences in the frequency of graft kinking and stenosis degree at the kink site between pedicled and skeletonized grafts. METHODS: Postoperative angiography was performed for all cases. In pedicled (n = 65) and skeletonized (n = 129) groups, the results of postoperative graft angiography were analyzed to investigate the presence of graft kinking and stenosis degree at the kink site. RESULTS: Kinking was observed in 4 (5.9%) and 9 (3.9%) arteries in the pedicled and skeletonized groups, respectively (p = 0.341). The stenosis degree at the kink site (mean +/- SD) was significantly higher in the skeletonized group (47.2 +/- 16.8%) than in the pedicled group (23.5 +/- 13.7%), (p = 0.032). In four patients in whom early postoperative angiography showed a kink with more than 50% stenosis, late-term angiography was performed. All four cases showed regression of the stenosis degree at the kink site. CONCLUSIONS: When the ITA had a kink, the stenosis degree at the kink site was significantly higher in the skeletonized group than in the pedicled group. Late angiography often reveals regression of stenosis at the kink site. Immediate intervention need not always be performed if the patient has no angina caused by a stenotic lesion at the kink site.     

Gelatin sheet incorporating basic fibroblast growth factor enhances sternal healing after harvesting bilateral internal thoracic arteries

OBJECTIVE: We previously reported that a gelatin sheet incorporating basic fibroblast growth factor accelerated sternal healing after bilateral internal thoracic artery removal in normal and diabetic rats. The aim of this study was to evaluate the effects of this therapeutic modality on sternal healing in a large-animal model before performing a clinical trial. METHODS: After median sternotomy and bilateral internal thoracic artery removal in a pedicled fashion, 14 beagle dogs received either a gelatin sheet incorporating basic fibroblast growth factor (100 mug per sheet) on the posterior table of the sternum (FGF group, n = 7) or did not receive a gelatin sheet (control, n = 7). We compared sternal healing 4 weeks after surgical intervention between the groups. RESULTS: Scintigraphic images obtained by using technetium 99 methylene diphosphonate bone scanning were assessed visually, and the impulse rate was quantified 30 and 60 minutes after injection of technetium 99 methylene diphosphonate to evaluate the sternal perfusion. Sternal uptake was significantly increased in the FGF group (30 minutes: 221% +/- 30% vs 180% +/- 36%; 60 minutes: 267% +/- 26% vs 197% +/- 42%; P <.01). Apparent sternal dehiscence, as assessed radiographically, was observed only in the control animals. Histologically, complete healing of the sternum with marked angiogenesis was observed in the FGF group, whereas poor healing with limited angiogenesis was seen in the control animals. Both bone mineral content (134 +/- 49 vs 52 +/- 32 mg, P <.01) and bone mineral density (133 +/- 53 vs 66 +/- 32 mg/mm(2), P <.05) along the incision line of the sternum, as assessed by means of dual-energy x-ray absorptometry, were higher in the FGF group. CONCLUSIONS: A gelatin sheet incorporating basic fibroblast growth factor enhances sternal perfusion and accelerates sternal bone healing in large animals.23     

Composite arterial grafting with double skeletonized internal thoracic arteries.

OBJECTIVES: Composite arterial grafting is a surgical technique for arterial myocardial revascularization, in which free arterial conduits are proximally anastomosed end-to-side to an intact internal thoracic artery (ITA). This report describes technical aspects and results of composite grafting using bilateral skeletonized ITAs. METHODS: From April 1996 to February 1999, 1057 patients underwent coronary artery bypass grafting (CABG) using bilateral skeletonized internal thoracic arteries. In 600 of them (57%), composite arterial grafting was performed. There were 452 men and 148 women. The mean age was 69 +/- 7 years. Two-hundred and six patients (34%) were diabetics, 84 (14%) had severe left ventricular dysfunction (ejection fraction of < 35%), and 26 (4.3%) underwent emergency operations. In 574 patients, the right ITA was used as a free graft connected to the in-situ left ITA. In 26, the free left ITA was attached to the in-situ right ITA, and in 38, mini-composite grafts (free distal left ITA on the left ITA, or free distal right ITA on the right ITA) were constructed. The average number of grafts was 3.0/patient (range, 2--6). RESULTS: The operative mortality was 2.8% (n = 17), and there were ten (1.7%), deep sternal wound infections. The mean follow-up was 25 months (range, 14--36 months). The 3-year survival was 92.5%. Ninety-seven percent of the surviving patients were angina-free. CONCLUSIONS: We currently perform this surgery routinely in most patients referred for CABG, and regard bilateral skeletonized internal thoracic arteries as the most appropriate arterial conduits for the composite technique.     

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.     

Sternal wound infections in patients after coronary artery bypass grafting using bilateral skeletonized internal mammary arteries

OBJECTIVES: This study evaluated the risks of sternal wound infections in patients undergoing myocardial revascularization using bilateral skeletonized internal mammary arteries (IMAs). BACKGROUND: The skeletonized IMA is longer than the pedicled one, thus providing the cardiac surgeon with increased versatility for arterial myocardial revascularization without the use of vein grafts. It is isolated from the chest wall gently with scissors and silver clips, and no cauterization is employed. Preservation of collateral blood supply to the sternum and avoidance of thermal injury enable more rapid healing and decrease the risk of sternal wound infection. METHODS: From April 1996 to August 1997, 545 patients underwent arterial myocardial revascularization using bilateral skeletonized IMAs. The right gastroepiploic artery was used in 100 patients (18%). The average age of the patients was 65 years; 431 (79%) were men and 114 (21%) were women; 179 (33%) were older than 70 years of age; 166 (30%) were diabetics. The average number of grafts was 3.2 per patient. RESULTS: The 30-day operative mortality rate was 2% (n = 11). There were six perioperative infarcts (1.1%) and six strokes (1.1%); 9 patients had sternal infection (1.7%) and 15 (2.8%) had superficial infection. Risk factors for sternal infection were chronic obstructive pulmonary disease and emergency operation. Superficial sternal wound infections were more common in women and in patients with chronic obstructive pulmonary disease, renal failure, or peripheral vascular disease. The 1-year actuarial survival rate was 97%. Two of the six late deaths were not cardiac-related. Late dehiscence occurred in three patients (0.6%). The death rate (early and late) of patients with any sternal complication was higher than that of patients without those complications (33% vs. 2.7%). CONCLUSIONS: Routine arterial myocardial revascularization using bilateral skeletonized IMAs is safe, and postoperative morbidity and mortality rates are low, even in elderly patients and those with diabetes. Chronic obstructive pulmonary disease and emergency operations were found to be associated with an increased risk of sternal infections, and the authors recommend avoiding the use of bilateral skeletonized IMAs in patients with these preoperative risk factors.     

Skeletonization of gastroepiploic artery graft in off-pump coronary artery bypass grafting: early clinical and angiographic assessment

BACKGROUND: Recently skeletonization has been recognized as an alternative to pedicle harvesting of the internal thoracic artery as a technique that increases the length and caliber size of the graft compared with pedicled internal thoracic artery grafts; however, this is not yet popular for harvesting the gastroepiploic artery (GEA). We report here our experience of skeletonized GEA grafting in off-pump coronary artery bypass grafting with early clinical and angiographic results. The purpose of this study was to evaluate skeletonization of GEA grafting in off-pump coronary artery bypass grafting with a large patient volume. METHODS: One hundred sixty-eight patients including 131 men and 37 women (mean age, 65 years; range, 45 to 87 years) underwent the skeletonized GEA grafting in off-pump coronary artery bypass grafting. These patients represent 41% (168 of 407 patients) of those who underwent off-pump coronary artery bypass grafting operations during the same period. We used the GEA graft of choice in patients with right coronary artery lesion. Skeletonization was performed in a unique manner we developed. RESULTS: There were no in-hospital deaths among the study patients. One patient had a perioperative myocardial infarction, which was considered a result of vasospasm of the GEA graft. None of the other patients had severe morbidity. The patency rate of the skeletonized GEA graft was 98.1% (151 of 154 distal anastomoses). CONCLUSIONS: This study suggests that skeletonization of the GEA graft can enlarge its caliber size and improve its flow capacity. In addition, the acceptable early clinical and angiographic outcome suggests that use of the skeletonized GEA graft in off-pump coronary artery bypass grafting surgery is safe and effective.     

Bilateral internal thoracic artery grafting in diabetic patients: short-term and long-term results of a 515-patient series

BACKGROUND: Despite potential long-term benefits, bilateral internal thoracic artery grafting in diabetics remains controversial because of the risk of sternal infection. We sought to assess the short- and long-term outcome after left-sided bilateral internal thoracic artery grafting and to determine the configuration of choice in diabetic subsets. METHODS: Between 1996 and 2001, 515 diabetics underwent isolated left-sided skeletonized bilateral internal thoracic artery grafting. The outcome of 468 consecutive oral-treated diabetics and 47 selective insulin-treated patients was analyzed. Patients undergoing T-grafting were compared with those undergoing in situ bilateral internal thoracic artery arrangements. RESULTS: The respective rates for early mortality and sternal infections were 2.4% and 1.9% in oral-treated diabetics and 6.3% and 4.3% in insulin-treated diabetics. Multivariate correlates of sternal infection were chronic lung disease (odds ratio, 10), obesity (odds ratio, 7), reoperation (odds ratio, 22), and a creatinine level of 2 mg/dL or more (odds ratio, 8). Five-year survival was 82%. The T-graft (n = 437) and in situ (n = 162) subgroups had comparable baseline profiles. Freedom from cardiac mortality at 6.5 years was 95.6% and 87.6% (P =.277), and freedom from repeat revascularization was 91.5% and 92.7% (P =.860), respectively. The choice of bilateral internal thoracic artery configuration did not appear as a correlate of mortality, cardiac mortality, or major adverse cardiac events. Complementary right-sided gastroepiploic artery (hazard ratio, 0.36) and sequential (hazard ratio, 0.55) grafting were identified as protective factors against the occurrence of major adverse cardiac events. CONCLUSIONS: Routine skeletonized bilateral internal thoracic artery grafting can be implemented safely in oral-treated diabetics. This strategy is associated with a favorable late cardiac outcome and is thus recommended. Both left-sided bilateral internal thoracic artery configurations provide comparable short- and long-term outcomes.     

Intraoperative and laboratory evaluation of skeletonized versus pedicled internal thoracic artery

Background. The skeletonization of internal thoracic artery is postulated to improve graft length, early blood flow, sternal blood supply, and postoperative respiratory function. Concern exists that skeletonization may injure internal thoracic artery, precluding good results of surgery. Reports on endothelial function of skeletonized internal thoracic artery are lacking.

Methods. A prospective assessment of early clinical outcomes of 357 consecutive patients undergoing coronary artery bypass grafting was performed: 287 patients with nonskeletonized and 70 with skeletonized left internal thoracic artery (LITA). The lengths of LITA and of its discarded distal segment, as well as free LITA blood flow, were measured. The dose-effect relationship for relaxation to acetylcholine was studied in the organ bath.

Results. Apart from a higher incidence of breaching the pleura with nonskeletonized LITA the clinical outcomes were comparable. The length of skeletonized LITA was 17.8 ± 1.14 cm versus 20.3 ± 0.52 cm skeletonized (p = 0.11). The length of discarded LITA was shorter in nonskeletonized artery (0.8 ± 0.28 cm versus 2.6 ± 0.49 cm; p = 0.022). The free LITA blood flow was 66.3 ± 7.42 mL/min in nonskeletonized vessel versus 100.3 ± 14.84 mL/min in skeletonized (p = 0.048). The acetylcholine-induced relaxation was similar in both groups (maximal relaxation, 80.7% ± 5.95% in nonskeletonized versus 72.9% ± 9.11% in skeletonized; not significant; negative logarithm of half-maximal effect, 7.43 ± 0.18 versus 7.1 ± 0.10, respectively; p = 0.063).

Conclusions. Skeletonization does not damage the endothelial function of the LITA. Higher free blood flow and available LITA length should encourage the use of skeletonized LITA in clinical practice.     

Bilateral skeletonized internal thoracic artery grafting in 303 patients seventy years and older

OBJECTIVES: Higher patency rates of the internal thoracic artery have led myocardial revascularization with bilateral internal thoracic arteries to be a procedure designated primarily for young patients. Fewer leg wound complications and sternal collateral flow preservation with the skeletonizing dissection technique can make bilateral internal thoracic artery grafting attractive also for elderly patients. METHODS: Between May 1996 and May 1998, 303 consecutive patients aged 70 years or older (mean age 75.5 years; range 70-92 years) underwent coronary artery bypass grafting with double skeletonized internal thoracic arteries. Forty-four (14.5%) patients were 80 years or older, and 89 (28%) had diabetes. The mean number of grafts was 3.1 per patient (2-6). RESULTS: Operative mortality was 2.6% (n = 8): it was higher for octogenarians (6.8%) than for younger patients (1.9%) (P =.06). The only significant preoperative predictors of early mortality were complicated percutaneous transluminal coronary angioplasty (P =.03) and preoperative use of intra-aortic balloon pumping (P =.03). Six patients (2%) had sternal wound infections for which chronic lung disease (P =.02) and emergency operation (P =.006) were the only significant predictors. Twenty-two (7.2%) late deaths occurred, and 1- and 3-year survivals were 93% and 90%, respectively. The 3-year survival of patients 80 years old or older was 92%. CONCLUSIONS: Bilateral grafting of the skeletonized internal thoracic artery carries relatively low morbidity and mortality in elderly patients and can be recommended for selected patients including octogenarians.