Single Internal Thoracic Artery Research Articles

Bilateral internal thoracic arteries: what is the State of the ART?

To provide a broad overview of the current state of knowledge of coronary artery bypass grafting with bilateral internal thoracic artery (BITA). There exists a large body of literature from mostly observational studies supporting the use of BITA in patients undergoing coronary artery bypass grafting but selection bias is a major issue with nonrandomized data. The precise method of BITA use does not appear to impact graft patency nor clinical outcomes - in other words, BITA in any configuration appears to be protective. The major downside is the increased risk of sternal complications, which can be mitigated with sternal-sparring adjuncts. The 5-year interim results of the landmark Arterial Revascularization Trial comparing BITA versus single internal thoracic artery did not show a clinical benefit for BITA but the end-of-trial results are pending. Despite wide guideline support for BITA use, uptake in the surgical community remains low and this is likely because of technical and institutional barriers. The published literature thus far supports surgical revascularization with BITA and we eagerly await the 10-year Arterial Revascularization Trial results. The general consensus is that a greater proportion of surgical revascularization should be performed using BITA.

Similar Outcomes in Diabetes Patients After Coronary Artery Bypass Grafting With Single Internal Thoracic Artery Plus Radial Artery Grafting and Bilateral Internal Thoracic Artery Grafting

The purpose of this study was to determine in patients with diabetes mellitus whether single internal thoracic artery (SITA) plus radial artery (RA) grafting yields outcomes similar to those of bilateral internal thoracic artery (BITA) grafting. From January 1994 to January 2011, 1,325 diabetic patients underwent primary isolated coronary artery bypass graft surgery with either (1) SITA plus RA with or without saphenous vein (SV) grafts (n= 965) or (2) BITA with or without SV grafts (n= 360); an internal thoracic artery was used in all patients to graft the left anterior descending coronary artery. Endpoints were in-hospital outcomes and time-related mortality. Median follow-up was 7.4 years, with a total follow-up of 9,162 patient-years. Propensity score matching was performed to identify 282 well-matched pairs for adjusted comparisons. Unadjusted in-hospital mortality was 0.52% for SITA plus RA with or without SV grafts and 0.28% for BITA with or without SV grafts, and prevalence of deep sternal wound infection was 3.2% and 1.7%, respectively. Unadjusted survival at 1, 5, 10, and 14 years was 97%, 88%, 68%, and 51% for SITA plus RA with or without SV grafts, and 97%, 95%, 80%, and 66% for BITA with or without SV grafts, respectively. Among propensity-matched patients, in-hospital mortality (0.35% versus 0.35%) and prevalence of deep sternal wound infection (1.4% versus 1.4%) were similar (p > 0.9) in the two groups, as was 1-, 5-, 10-, and 14-year survival: 97%, 90%, 70%, and 58% for SITA plus RA with or without SV grafting versus 97%, 93%, 79%, and 64% for BITA with orwithout SV grafting, respectively (early p= 0.8, late p= 0.2). For diabetic patients, SITA plus RA with or without SV grafting and BITA with or without SV grafting yield similar in-hospital outcomes and long-term survival after coronary artery bypass graft surgery. Therefore, both SITA plus RA and BITA plus SV grafting should be considered for these patients.

Invited Commentary

Invited Commentary

Is bilateral internal thoracic artery grafting a safe option for chronic dialysis patients?

The use of bilateral internal thoracic artery (BITA) grafting has been proposed for dialysis patients with multivessel coronary artery disease, primarily because of hypothetical long-term survival benefits. To investigate the outcome of BITA grafting in dialysis patients. This was a retrospective analysis of the use of BITA grafting in 105consecutive patients with end-stage renal failure on chronic dialysis in three European centres with extensive experience in BITA. Baseline patient characteristics, operative data, early postoperative complications and late survival were reviewed. Outcomes of patients from one of the three centres who underwent either BITA (n=40) or single internal thoracic artery (SITA) grafting (n=19) were also analysed; a one-to-one propensity score (PS)-matched analysis was performed. There were 19 (18.1%) hospital deaths. Despite differences in preoperative patient characteristics and surgical features, in each centre, hospital mortality was greater than the 75th percentile of expected operative risk (EuroSCORE II). Diseased ascending aorta and extracardiac arteriopathy were found to be predictors of hospital death (odds ratio 9.7; P=0.006) and complicated hospital course (odds ratio 2.54; P=0.035), respectively. The 7-year non-parametric estimates of freedom from all-cause death and cardiac or cerebrovascular death were 59% (95% confidence interval: 52.3-65.7%) and 75.6% (95% confidence interval: 71.2-80%), respectively. There were no significant differences in early and late outcomes between BITA and SITA PS-matched groups. BITA grafting remains a risky operation for chronic dialysis patients, even when performed routinely. No long-term survival benefits for the use of BITA versus SITA were proven.

Associations Between Adding a Radial Artery Graft to Single and Bilateral Internal Thoracic Artery Grafts and Outcomes: Insights From the Arterial Revascularization Trial.

Whether the use of the radial artery (RA) can improve clinical outcomes in coronary artery bypass graft surgery remains unclear. The ART (Arterial Revascularization Trial) was designed to compare survival after bilateral internal thoracic artery (BITA) over single left internal thoracic artery (SITA). In the ART, a large proportion of patients (≈20%) also received an RA graft instead of a saphenous vein graft (SVG). We aimed to investigate the associations between using the RA instead of an SVG to supplement SITA or BITA grafts and outcomes by performing a post hoc analysis of the ART. Patients enrolled in the ART (n=3102) were classified on the basis of conduits actually received (as treated). The analysis included 2737 patients who received an RA graft (RA group; n=632) or SVG only (SVG group; n=2105) in addition to SITA or BITA grafts. The primary end point was the composite of myocardial infarction, cardiovascular death, and repeat revascularization at 5 years. Propensity score matching and stratified Cox regression were used to compare the 2 strategies. Myocardial infarction, cardiovascular death, and repeat revascularization cumulative incidence was 2.3% (95% confidence interval [CI], 1.1-3.4), 3.5% (95% CI, 2.1-5.0), and 4.4% (95% CI, 2.8-6.0) in the RA group and 3.4% (95% CI, 2.0-4.8), 4.0% (95% CI, 2.5-5.6), and 7.6% (95% CI, 5.5-9.7) in the SVG group, respectively. The composite end point was significantly lower in the RA group (8.8%; 95% CI, 6.5-11.0) compared with the SVG group (13.6%; 95% CI, 10.8-16.3; P=0.005). This association was present when an RA graft was used to supplement both SITA and BITA grafts (interaction P=0.62). This post hoc ART analysis showed that an additional RA was associated with lower risk for midterm major adverse cardiac events when used to supplement SITA or BITA grafts. URL: https://www.situ.ox.ac.uk/surgical-trials/art. Unique identifier: ISRCTN46552265.

Abstract 331: Are Two Internal Thoracic Grafts Better Than One in Patients With Peripheral Vascular Disease?: Analysis of 858 Cases Between 1996- 2011

Objectives: Bilateral internal thoracic artery( ITA) grafting is associated with improved survival. However, potential survival benefit of using two ITA`s in patients with peripheral vascular disease(PVD) is questionable due to their short life expectancy and the increased risk of sternal wound infection(SWI) compare to operations incorporating single ITA (SITA). The purpose of this study is to compare early and long-term outcome of bilateral ITA grafting(BITA) to that of SITA and vein grafts in PVD patients with multi-vessels coronary disease. Methods: Five hundred and thirty three PVD patients who underwent BITA between 1996 and 2011 were compared with 319 who underwent SITA . Results: SITA patients were more often female, more likely to have Diabetes, chronic obstructive lung disease, unstable angina, previous CABG, renal insufficiency, Cerebro- vascular disease and emergency operation .On the other hand congestive heart failure and triple vessel coronary disease were more prevalent among BITA patients. Operative mortality(3.5% vs. 4.1%, in the SITA and BITA respectively) and occurrences of SWI (6.6% vs 3.9%) and strokes(4.1% vs 6.8%) were not significantly different between groups . BITA patients did not have better Kaplan- Meier 10 year survival ( 52.1% vs.47.1%, p=0.145) and after propensity score matching(243 well matched pairs) BITA was not associated with better adjusted survival ( HR 1.108[95%CI 0.810-1.516] p=0.521)(cox model) Conclusion: This study does not support routine use of BITA in PVD patients .Earlier mortality from non-cardiac causes, reduces contribution of BITA and increases the influence of PVD and other co-morbidities on survival. Selective use of BITA in lower risk patients might un-mask the benefits of BITA

Impact of dual antiplatelet therapy after coronary artery bypass surgery on 1-year outcomes in the Arterial Revascularization Trial.

There is still little evidence to boldport routine dual antiplatelet therapy (DAPT) with P2Y12 antagonists following coronary artery bypass grafting (CABG). The Arterial Revascularization Trial (ART) was designed to compare 10-year survival after bilateral versus single internal thoracic artery grafting. We aimed to get insights into the effect of DAPT (with clopidogrel) following CABG on 1-year outcomes by performing a post hoc ART analysis. Among patients enrolled in the ART (n = 3102), 609 (21%) and 2308 (79%) were discharged on DAPT or aspirin alone, respectively. The primary end-point was the incidence of major adverse cerebrovascular and cardiac events (MACCE) at 1 year including cardiac death, myocardial infarction, cerebrovascular accident and reintervention; safety end-point was bleeding requiring hospitalization. Propensity score (PS) matching was used to create comparable groups. Among 609 PS-matched pairs, MACCE occurred in 34 (5.6%) and 34 (5.6%) in the DAPT and aspirin alone groups, respectively, with no significant difference between the 2 groups [hazard ratio (HR) 0.97, 95% confidence interval (CI) 0.59-1.59; P = 0.90]. Only 188 (31%) subjects completed 1 year of DAPT, and in this subgroup, MACCE rate was 5.8% (HR 1.11, 95% CI 0.53-2.30; P = 0.78). In the overall sample, bleeding rate was higher in DAPT group (2.3% vs 1.1%; P = 0.02), although this difference was no longer significant after matching (2.3% vs 1.8%; P = 0.54). Based on these findings, when compared with aspirin alone, DAPT with clopidogrel prescribed at discharge was not associated with a significant reduction of adverse cardiac and cerebrovascular events at 1 year following CABG.

Bilateral internal thoracic artery grafting in India—Time to raise the bar

ObjectivesBilateral internal thoracic artery (BITA) grafting strategy is the current trend in coronary artery bypass grafting for multivessel coronary artery disease. Although better long-term outcomes have been shown, BITA grafting is underutilized as a main strategy for revascularization by most of the surgeons. The survey was conducted to ascertain the current usage and concerns of BITA grafting in India. MethodsDatabase of 856 Indian cardiac surgeons currently with predominantly adult practice was prepared and a questionnaire was sent about use of single and bilateral ITA grafts and BITA grafting strategy in different clinical scenarios. ResultsA total of 112 surgeons (13.08%) from 75 institutions responded and 92 surgeons (10.7%) completed the survey. Single ITA is used by 79% of surgeons in more than 90% of their patients. 31% and 29% of surgeons use BITA grafting in 5–10% and 11–98% of their patients respectively. 53% of surgeons avoided the usage of BITA grafting in patients with smoking, 35% of surgeons in chronic obstructive pulmonary disease, 58% of surgeons in obesity and 62% of surgeons in acute coronary syndrome, 36% of surgeons in patients with left ventricular dysfunction and 61% of surgeons in patients with poor coronary anatomy. The concerns for BITA usage are risk of deep sternal wound infection (DSWI) (40%), increased operative time (27%), unknown superiority (12%) and limited length of right ITA (5%). ConclusionsThe usage of BITA grafting is restricted to 10% in India and main concerns are DSWI and increased operative time.

Comparison of radial and bilateral internal thoracic artery grafting in patients with peripheral vascular disease†.

The composite T-graft with radial artery (RA) attached end-to-side to the left internal thoracic artery (ITA) provides arterial myocardial revascularization without the increased risk of deep sternal wound infection associated with harvesting 2 ITAs. However, many surgeons are reluctant to use RA in patients with peripheral vascular disease (PVD) due to concerns regarding the quality of the conduit in this subset of patients. The purpose of this study is to compare early- and long-term outcomes of arterial grafting with bilateral ITAs (BITA) to that of single ITA and RA in patients with PVD. Between 1999 and 2010, 619 consecutive patients with PVD (500 BITAs and 119 single ITA and RA) underwent myocardial revascularization in our institution. Occurrence of following risk factors as female sex, age 70+, diabetes, unstable angina, emergency operation, cerebrovascular disease and chronic obstructive pulmonary disease was higher in the RA-ITA group. The RA-ITA group also had a higher logistic EuroSCORE (22.1 vs 13.3). Operative mortality and occurrence of deep sternal wound infection of the two groups was similar (4.2% vs 5.0% and 2.5% vs 4.0% for the radial and bilateral ITA, respectively). Median follow-up was 9.75 years. Unadjusted Kaplan-Meier 10-year survival of the two groups was similar (44.1% vs 49.6%, P = 0.7). After propensity score matching (100 pairs), assignment to BITA was not associated with better adjusted survival (hazard ratio 0.593, 95% confidence interval 0.265-1.327, P = 0.20, Cox model). In patients with PVD, complete arterial revascularization with left ITA and RA can be justified with regards to survival.

Perioperative outcomes of off-pump minimally invasive coronary artery bypass grafting with bilateral internal thoracic arteries under direct vision†.

We previously introduced techniques to harvest and use the right internal thoracic artery in minimally invasive coronary artery bypass grafting (CABG) via a single left thoracotomy for revascularization with bilateral internal thoracic arteries (BITA). We report our short-term outcomes of patients who underwent minimally invasive CABG using BITA and a single internal thoracic artery (SITA). Consecutive patients who underwent minimally invasive CABG using BITA or SITA at a Japanese medical center between February 2012 and December 2015 were reviewed retrospectively. Preoperative, intraoperative and 30-day postoperative outcomes were analysed. Perioperative data for the SITA cohort is presented to provide a context in which the outcomes of the BITA cohort can be evaluated. A total of 25 and 37 patients underwent BITA and SITA revascularization, respectively. The mean duration of the operation was longer in the BITA group than in the SITA group (265 ± 104 vs 336 ± 73 min). There were no deaths in the BITA group and one death in the SITA group. There were no strokes in either cohort, and new haemodialysis was required in one patient in each group. All BITA grafts were harvested without major complications and were all patent on computed tomography angiograms 1 week following the operations. BITA can be safely harvested in a reproducible manner under direct vision via a small left thoracotomy. The potential advantages of minimally invasive CABG using BITA, although yet to be established, include a long-term survival benefit conferred by BITA grafts and elimination of the risk of sternal wound infection, in addition to the established advantages of minimally invasive coronary artery surgery. This approach has the potential for further optimization with hybrid revascularization strategies.

One or Two Internal Thoracic Grafts? Long-Term Follow-Up of 957 Off-Pump Coronary Bypass Surgeries

The potential survival benefit of bilateral internal thoracic artery (BITA) grafting in patients undergoing off-pump coronary artery bypass graft surgery (OPCABG) is controversial owing to the technical complexity of these operations. Our objective was to compare the outcome of patients undergoing OPCABG with BITA to the outcome of patients undergoing OPCABG with a single internal thoracic artery (SITA) and saphenous vein grafts or radial artery. Five hundred and thirty-five consecutive patients who underwent OPCABG BITA at our institute between 2000 and 2008 were compared with 422 patients who underwent OPCABG with SITA. Propensity score matching was used to account for differences between groups in preoperative characteristics. Being female (20.9% versus 36.0%, p < 0.001), having diabetes mellitus (36.6% versus 55.7%, p > 0.001), recent myocardial infarction (23.6% versus 33.2%, p>0.001), aged 70 years or more (41.1% versus 49.8%, p=0.001), peripheral vascular disease (26.1% versus 46.7%, p > 0.001), and chronic renal failure (7.9% versus 15.9%, p > 0.001) were less frequent in the BITA group than in the SITA group, respectively. The European System for Cardiac Operative Risk Evaluation score was significantly higher for the SITA group (7.62, versus 5.46 for BITA group, p= 0.001), whereas operative mortality (1.7% BITA versus 2.6% SITA) and sternal wound infections (1.7% BITA versus 2.1% SITA) were similar. The mean follow-up was 11.6 ± 3.5 years. The BITA patients' 10-year survival (Kaplan-Meier) was better (72.2% versus 55.1% for SITA, p> 0.001). However, after propensity matching, survival for BITA and SITA were similar. This large cohort study suggests that long-term outcomes for patients undergoing OPCABG are not better with BITA grafting.

Bilateral Versus Single Internal Thoracic Artery Grafting in Diabetic and Older Patients with Triple Vessel Disease: Analysis of a Multicentre Database

Background: Use of bilateral internal thoracic arteries (BITA) is associated with improved long-term survival compared to a single internal thoracic artery (SITA), despite its low penetrance in clinical practice. Such a strategy is arguably less desirable in patients who are older and those who have diabetes, due to a perceived increase in perioperative risk with limited prognostic gain associated with BITA. As such, we sought to examine the prevalence and outcomes of BITA use in this subset of patients. Methods: From 2001 to 2013, 25,900 patients at 28 centres with three-vessel coronary disease underwent primary isolated coronary artery bypass grafting (CABG) using at least a single ITA. BITA use was 12% overall, 15% (n = 2379) in those under 70 years of age (n = 15879) and 6.6% (n = 661) in those over 70 years (n = 10016), p < 0.001. Amongst those with diabetes (n = 7948), BITA use was 7.4% (n = 590). Separate propensity-score matched analyses were conducted for the following subsets: 1) over 70 years of age, 2) under 70 years of age and 3) those with diabetes (treated with either oral agents or insulin). The National Death Index was used to determine survival. Results: In the propensity-score matched analysis comparing single versus bilateral ITA in those over 70 years of age (619 matched pairs), there were comparable rates of sternal infection (1.1% vs. 2.1%, p = 0.26) but a trend towards higher 30-day mortality (SITA: 1.1% vs. BITA: 2.7%, p = 0.064). Survival at 8 years was also comparable (SITA: 74 ± 3.2% vs. BITA: 72 ± 3.1%, p = 0.88). In the analysis amongst patients under 70 (2193 matched pairs), 30-day mortality was similar (SITA: 0.3% vs. BITA: 0.5%, p = 0.48), however BITA patients experienced higher rates of sternal infection (0.8% vs. 1.8%, p = 0.008). Survival at 8 years was nonetheless comparable (SITA: 92 ± 1.3% vs. BITA: 92 ± 0.9%, p = 0.29). Amongst patients with diabetes (564 matched pairs), 30-day mortality was comparable (SITA: 0.9% vs. BITA: 2.0%, p = 0.21), as was sternal infection (2.5% vs. 4.1%, p = 0.18). Survival was similar at 8 years (BITA: 84 ± 2.7% vs. SITA: 78 ± 3.8%, p = 0.47). Conclusions: Use of bilateral internal thoracic arteries remains relatively uncommon, especially in older patients and those with diabetes. It is associated with increased rates of deep sternal infection although early mortality was comparable. Mid-term survival was comparable between patients receiving either single or bilateral internal thoracic artery grafting. As such, the benefit of bilateral ITA grafting may lie only in those with longer life expectancies.

Composite Y-Grafting Using the Left Internal Thoracic Artery: Survival and Angiography in 198 Cases.

Extended left internal thoracic artery (LITA) harvesting allows maximal grafting to the anterior and lateral walls with a single ITA conduit. This study evaluates outcomes following the use of a LITA Y graft as the primary grafting strategy. Patients who underwent LITA composite Y-grafting (n=198) between 1995 and 2009 were identified from a cardiac surgical database. Follow-up (mean 13.1 years) was obtained by cross-reference with the state death registry and local cardiology databases. Operative mortality was zero in the 168 patients who underwent isolated CABG and was 3.5% overall. There were no episodes of perioperative myocardial infarction. Kaplan-Meier 10-year survival was 75.9%. Independent predictors of worse late survival were age, diabetes, chronic obstructive pulmonary disease and pre-existing left ventricular dysfunction. There were 53 episodes of post-discharge angiography at an average of 5.8 years post LITA Y grafting. Twenty cases of LITA Y graft failure were identified, predominantly affecting the free limb (n=15). The ratio of symptom driven angiography to Y graft failure increased over time. Eighteen patients required revascularisation, percutaneous intervention in 15 and reoperative coronary bypass in three. Left Internal Thoracic Artery Y grafting is a feasible revascularisation strategy with satisfactory outcomes. These are comparable to other arterial composite graft configurations. A LITA Y allows efficient conduit use without compromising the in situ LITA graft.

Short-term outcomes associated with bilateral internal thoracic artery grafting

Background: Bilateral internal thoracic artery (BITA) grafting is associated with improved long-term survival and graft patency compared to single internal thoracic artery (SITA) graft and saphenous vein graft in coronary artery bypass grafting (CABG). However, BITA grafting may adversely affect early in hospital mortality and morbidity due to deep sternal wound infection. Hence, we carried out this study to evaluate early outcomes of BITA grafting in different configuration in our hospital and to assess safety and applicability of BITA grafting as a routine procedure.Methods: A retrospective cross sectional study was conducted in September 2014 where all 134 patients using bilateral ITA for coronary artery bypass (CABG) at United Hospital, Dhaka, Bangladesh from January 2009 to September 2014 were included. BITA grafting were used in either in-situ or Y-graft technique. We reviewed and evaluated patients’ characteristics and short-term outcomes. The short-term outcomes included in hospital mortality and major morbidities.Results: Out of 134 patients, 129 (96%) patients were male. The mean age was 48.73 ± 8.42 yrs ranging from 28 to 72 yrs. Hypertension and smoking were the most common cardiac risk factors. There was no mortality in both BITA in-situ and BITA Y-graft groups. Most common postoperative complications were fever (26%), and arrhythmia (7.5%). Only one female patient (0.7) had sternal wound complication. Elderly, obesity and COPD were not observed to be associated with sternal wound complication.Conclusion: Short-term outcomes of BITA grafting for CABG is excellent with no significant difference between BITA in-situ and BITA Y-graft groups.Bangladesh Heart Journal 2016; 31(1) : 3-9

Does a similar procedure result in similar survival for women and men undergoing isolated coronary artery bypass grafting?

ObjectivesTo (1) identify sex-related differences in risk factors and revascularization strategies for patients undergoing coronary artery bypass grafting (CABG), (2) assess whether these differences influenced early and late survival, and (3) determine whether clinical effectiveness of the same revascularization strategy was influenced by sex. MethodsFrom January 1972 to January 2011, 57,943 adults—11,009 (19%) women—underwent primary isolated CABG. Separate models for long-term mortality were developed for men and women, followed by assessing sex-related differences in strength of risk factors (interaction terms). ResultsIncomplete revascularization was more common in men than women (26% vs 22%, P < .0001), but women received fewer bilateral internal thoracic artery (ITA) grafts (4.8% vs 12%; P < .0001) and fewer arterial grafts (68% vs 70%; P < .0001). Overall, women had lower survival than men after CABG (65% and 31% at 10 and 20 years, respectively, vs 74% and 41%; P ≤ .0001), even after risk adjustment. Incomplete revascularization was associated equally (P > .9) with lower survival in both sexes. Single ITA grafting was associated with equally (P = .3) better survival in women and men. Although bilateral ITA grafting was associated with better survival than single ITA grafting, it was less effective in women—11% lower late mortality (hazard ratio, 0.89 [0.77-1.022]) versus 27% lower in men (hazard ratio, 0.73 [0.69-0.77]; P = .01). ConclusionsWomen on average have longer life expectancies than men but not after CABG. Every attempt should be made to use arterial grafting and complete revascularization, but for unexplained reasons, sex-related differences in effectiveness of bilateral arterial grafting were identified.

14-Year Results of Bilateral versus Single Internal Thoracic Artery Grafts for Left-Sided Myocardial Revascularization in Young Diabetic Patients.

Objectives Despite encouraging late outcomes, the use of bilateral internal thoracic artery (BITA) grafting for myocardial revascularization in diabetic patients remains controversial because of an increased risk of sternal wound complications. In the present study, early- and long-term outcomes of the use of left-sided BITA versus single internal thoracic artery (SITA) grafting in young (< 65 years of age) diabetic patients were reviewed retrospectively. Methods A total of 250 propensity score pair-matched diabetic patients, operated on between February 2000 and December 2011, receiving either BITA (n = 125) or SITA (n = 125) grafting were analyzed retrospectively. In each group, 104 patients were males, and mean age was 60.1 ± 5.3 years. Follow-up was 2.1 to 14.8 years (mean, 9.3 ± 3.5 years) and complete for 100%. Results Incidence of deep sternal wound infection was 2.4 versus 3.2% (p = 0.722). Rethoracotomy due to bleeding occurred in 4.8 versus 3.2% (p = 0.608). The 5-, 10-, and 14-year estimates of survival were 93.4, 76.6, and 67.5% (BITA) versus 89.5, 81.5, and 32.8% (SITA); p = 0.288. Freedom from reangiography/intervention (60.5 vs. 63.9%) during follow-up was comparable (p = 0.507) as well as infarction rate (93.8 vs. 95.1%, p = 0.833) and redoes (p = 0.672, exclusively valve surgery) were comparable. Freedom from thromboembolic or cerebrovascular events did not show any significant differences (94.0 vs. 94.0%, p = 0.78). Multivariate analysis identified poor ejection fraction as predictor for decreased long-term survival. Neither age nor gender or urgency had an influence on long-term mortality. Conclusion Left-sided BITA grafting may be performed routinely even in diabetic patients without increased incidence of postoperative wound-healing complications. Survival rates after 5, 10, and 14 years were comparable for BITA and SITA grafting.

Bilateral Internal Thoracic Artery Grafting Increases Mediastinitis: Myth or Fact?

There is controversy about the risk of mediastinitis associated with the use of both internal thoracic arteries (ITA). We performed a case-control study of patients operated on at a single institution from January 2003 to December 2014. A total of 3,118 consecutive patients undergoing isolated coronary artery bypass graft surgery were included; 81.3% (n= 2,533) underwent bilateral ITA (BITA) grafts exclusively and constitute the BITA group, and 18.7% (n= 585) constitute the single ITA (SITA) group. Mediastinitis was defined as deep tissue mediastinal infection, with clinical or microbiologic evidence. Continuous variables were expressed as mean ± SD, and categoric variables as percentage (range). Student's t test and Fisher's exact test were used, as appropriate. Propensity score matching analysis was performed according to the nearest neighbor estimation method (n= 1,040). The incidence of diabetes mellitus was similar in both groups (29%, p= 0.9). The BITA patients were more like to be younger (p < 0.001), men (p < 0.001), had a higher prevalence of hypertension (p < 0.01), higher body mass index (p < 0.001), lower prevalence of left ventricular dysfunction (p < 0.001) and of previous myocardial infarction (p < 0.01), and greater use of off-pump coronary artery bypass graft surgery (p < 0.01). The BITA patients had lower unadjusted hospital mortality (1.6%, versus 5.3% for SITA, p < 0.0001). The total incidence of mediastinitis was 1.8% (BITA 1.9% versus SITA 1.5%, p= 0.6). Diabetes (p < 0.01) and nonelective surgery (p= 0.004) were the only predictors of mediastinitis in the entire population. Propensity score matching showed no differences in mediastinitis: BITA 2.5% versus SITA 1.3% (p= 0.17). In this series of patients, BITA did not increase the risk of mediastinitis in the total population or in the propensity score matched subgroups.

Should Bilateral Internal Thoracic Artery Grafting Be Used in Patients With Diabetes Mellitus?

Bilateral internal thoracic artery (BITA) grafting in patients with diabetes mellitus is controversial because of a higher risk for sternal infection. The purpose of this study is to compare the outcome of BITA grafting to that of single ITA (SITA) grafting in patients with diabetes. Between 1996 and 2010, 964 diabetic patients with multivessel disease who underwent primary coronary artery bypass graft surgery with BITA were compared with 564 patients who underwent coronary artery bypass graft surgery with SITA and saphenous vein grafts. The SITA patients were older, more often female, more likely to have chronic obstructive pulmonary disease, ejection fraction 30% or less, insulin-dependent diabetes, recent myocardial infarction, renal insufficiency, peripheral vascular disease, and emergency operation. The BITA patients more often underwent coronary artery bypass graft surgery with three or more grafts. The two groups had similar operative mortality, 2.6% BITA versus 3.0% SITA, and sternal infection, 3.1% versus 3.9%, respectively. The mean follow-up was 12.2 ± 4.3 years. Unadjusted Kaplan-Meier 10-year survival of the BITA group was better than that of the SITA group (65.3% ± 3.1% versus 55.5% ± 4.5%, respectively; p= 0.004), After propensity score matching (490 well-matched pairs), Kaplan-Meier 10-year survival was not significantly different between the matched groups; however, the Cox-adjusted survival of the BITA patients was better (hazard ratio 0.729, 95% confidence interval: 0.551 to 0.964, p= 0.027). The findings of this large cohort study suggest that the long-term outcome of patients with diabetes and multivessel disease who undergo BITA grafting is better than that of diabetic patients who undergo coronary artery bypass graft surgery with SITA and saphenous vein grafts.

Abstract 520: Should Bilateral Internal Thoracic Artery Grafting be Used in Patients with Peripheral Vascular Disease?

Background: The potential survival benefit of Bilateral Internal Thoracic Artery (BITA) compared to Single Internal Thoracic Artery (SITA) grafting in peripheral or cerebral vascular disease (PVD) patients is questionable, due to their short life expectancy and increased risk of sternal wound infection. Methods: Six hundreds and four Patients with PVD who underwent BITA grafting between 1996 and 2010 were compared with 478 PVD patients who underwent SITA grafting. Results: Patients undergoing SITA were older, more often female, more likely to have chronic obstructive lung disease, EF&lt;30% ,Diabetes, renal insufficiency, congestive heart failure and emergency operation. Euroscore of SITA patients was significantly higher(10.1 ±3.1vs. 8.1± 3.3 %,p&lt;0.001) Operative mortality (4.4% vs. 5.0% in BITA and SITA)and sternal wound infections (4.4% vs. 3.6%) were not significantly different between groups. Median follow-up was 9.50 (95%CI 8.83-10.16) years. Ten-year survival (Kaplan-Meier ) of the SITA and BITA groups were not significantly different (45.1±4.7% vs. 50.1±3.4%, P =0.736, Log Rank test) and assignment to the BITA group was not associated with better propensity-adjusted survival (HR 1.050, 95% CI: 0.875-1.261, P =0.600) ( Stratified COX model. ) Conclusions: This study shows. that, early and long-term outcomes of BITA grafting in patients with PVD are not better than those of SITA grafting. Early mortality from non-cardiac causes ,reduces the influence of the type of conduit used(BITA or SITA) on survival. Selective use of BITA in lower-risk PVD patients might un-mask the benefits of BITA grafting

Invited Commentary

The authors of this study [1Rubens F.D. Chen L. Bourke M. Assessment of the association of bilateral internal thoracic artery skeletonization and sternal wound infection after coronary artery bypass grafting.Ann Thorac Surg. 2016; 101: 1677-1683Abstract Full Text Full Text PDF Scopus (25) Google Scholar] have again verified the safety of bilateral internal thoracic arterial (BITA) grafting in patients requiring coronary revascularization. Their sizeable experience involving a large cohort of patients comparing skeletonized pedicle harvesting with traditional pedicle harvesting techniques demonstrated equivalent rates of sternal infections and other related complications. Over time, arterial conduit use has become the standard of care, relegated to hallowed evidence-based acceptance in appropriately selected patients. However, despite the universal acceptance of single arterial grafting, ElBardissi and colleagues [2ElBardissi A.W. Aranki S.F. Sheng S. O’Brien S.M. Greenberg C.C. Gammie J.S. Trends in isolated coronary artery bypass grafting: an analysis of the Society of Thoracic Surgeons adult cardiac surgery database.J Thorac Cardiovasc Surg. 2012; 143: 273-281Abstract Full Text Full Text PDF PubMed Scopus (345) Google Scholar] revealed that only 4% to 12% of surgical revascularization procedures use BITA; clearly, evidence-based practice is rarely translated into routine clinical practice outside of reporting centers. Previous guidelines supporting arterial grafting with BITA conduits were often dependent on the severity of the native vessel disease; these studies often discouraged the use of BITA when the stenosis was not critical (<90%) [3Hillis L.D. Smith P.K. Anderson J.L. et al.American College of Cardiology Foundation/American Heart Association Task Force on Practice Guidelines2011 ACCF/AHA guideline for coronary artery bypass graft surgery: executive summary: a report of the American College of Cardiology Foundation/American Heart Association Task Force on Practice Guidelines.J Thorac Cardiovasc Surg. 2012; 143: 4-34Abstract Full Text Full Text PDF PubMed Scopus (186) Google Scholar]. In regards to sternal complications, Dorman and coworkers [4Dorman M.J. Kurlansky P.A. Traad E.A. Galbut D.L. Zucker M. Ebra G. Bilateral internal mammary artery grafting enhances survival in diabetic patients a 30-year follow-up of propensity score–matched cohorts.Circulation. 2012; 126: 2935-2942Crossref PubMed Scopus (123) Google Scholar] addressed the effects of diabetes in a high-volume center with extensive BITA use. An even earlier large-scale, multicenter randomized arterial revascularization trial (ART) compared revascularization using BITA for the two most important left-sided target arteries with single internal thoracic artery (ITA) coupled with a combination of radial arteries or venous conduits for the remaining graft sites. This study demonstrated equivalent low 30-day (1%) and 1-year (2.5%) mortality rates, as well as similar rates of stroke and myocardial infarction, and the need for repeat revascularization for BITA grafting compared with the more traditional single ITA grafting strategy. Of note in this study was the increased incidence of sternal wound healing complications requiring reconstruction (1.9% versus 0.6%) in BITA patients compared with single ITA use, especially in diabetic patients. Although this randomized trial used a variety of ITA harvesting techniques, the results suggested that skeletonization of the ITA during harvesting may yield fewer sternal complications [5Taggart D.P. Altman D.G. Gray A.M. et al.ART InvestigatorsRandomized trial to compare bilateral vs. single internal mammary coronary artery bypass grafting: 1-year results of the Arterial Revascularisation Trial (ART).Eur Heart J. 2010; 31: 2470-2481Crossref PubMed Scopus (303) Google Scholar]. It is clear that skeletonization affords the surgeon increased arterial conduit length, creating the potential for multiple grafts of the left coronary circulation with a longer left ITA, as well as improving the distal reach of the right coronary arterial target sites with a skeletonized right ITA. Importantly, the known risk factors for suspected increased sternal complications from BITA use (increased body mass index, diabetes, peripheral vascular disease, female sex, and preoperative anemia) are more related to full sternotomy itself, instead of ITA harvesting, and were not significantly different in this report. Bilateral ITA utilization strategies for complex coronary revascularization has clearly demonstrated safety, diminished future interventions, improved graft longevity, and increased patient survival rates. The current report provides further evidence that harvesting techniques matter; hopefully studies like these will prevail over the continued reluctance to commit to more arterial grafting among the cardiac surgery community. The authors are to be congratulated for their excellent results, as well as advancing our understanding of this important topic. Assessment of the Association of Bilateral Internal Thoracic Artery Skeletonization and Sternal Wound Infection After Coronary Artery Bypass GraftingThe Annals of Thoracic SurgeryVol. 101Issue 5PreviewSkeletonization is a technique of bilateral internal thoracic artery (BITA) harvest that preserves sternal blood flow. We sought to identify the relationship of skeletonization and sternal wound infection in a population undergoing BITA harvest. Full-Text PDF