Internal Thoracic Artery Group Research Articles

Bilateral versus single internal thoracic coronary artery bypass grafting: the ART RCT

Background There is debate whether the use of more arterial grafts during coronary artery bypass graft surgery provides advantages to the standard operation using the left internal thoracic artery plus vein grafts. We review data from the Arterial Revascularisation Trial to determine whether there is support for the multiple arterial graft hypothesis. Methods Patients undergoing coronary artery bypass graft for clinical reasons and who provided written informed consent were randomised to standard coronary artery bypass graft using the single internal thoracic artery or use of bilateral internal thoracic arteries. Additional vein grafts could be used. The primary outcome was all-cause mortality at 10 years and exploratory analyses were carried out to test the multiple arterial graft hypothesis. Results A total of 3102 patients were enrolled (1548 bilateral internal thoracic artery and 1554 single internal thoracic artery). Follow-up to 10 years for vital status was 98% complete. In the bilateral group, 14% of patients received a single internal thoracic artery only and use of radial artery grafts occurred in about 20% of patients in both groups. Aspirin was used in 81% of the patients, beta-blockers in 74%, statins in 90% and angiotensin-converting enzyme inhibitors or angiotensin receptor blockers in 73%. At 10 years, death rates were 20.3% and 21.2% in the bilateral internal thoracic artery and single internal thoracic artery groups, respectively (hazard ratio 0.96, 95% confidence intervals 0.82 to 1.12; p = 0.62) and composite of all-cause mortality, myocardial infarction or stroke 24.9% and 27.3%, respectively (hazard ratio 0.90, 95% confidence interval 0.79 to 1.03; p = 0.12). Exploratory analyses using the ‘as-treated’ approach indicate that outcomes were better in patients who received multiple arterial grafts (adding the right internal thoracic and/or radial arteries) compared with a single arterial graft. This effect appeared to be greater in patients with diabetes and those aged 70 years or less. Use of total arterial grafting without vein grafts may provide the best outcomes. Limitations The elevated cross-over rate between bilateral internal thoracic artery and single internal thoracic artery and the non-randomised use of radial artery grafts may have contributed to a loss of power to detect a difference in mortality between the two groups. Moreover, secondary analyses are prone to bias as they compare non-randomised groups. Conclusions The Arterial Revascularisation Trial is one of the largest long-term studies in cardiac surgery. The primary analysis did not show a mortality benefit for bilateral internal thoracic artery at 10 years, perhaps due to high crossover rates in the bilateral internal thoracic artery group and concomitant use of the radial artery. Secondary analyses suggest a mortality benefit for patients receiving multiple arterial grafts compared with single arterial graft with possible greater effects in patients with diabetes and separately in patients aged 70 years or above. The trial will follow patients to 15 years and the continuing Randomized Comparison of the Clinical Outcome of Single versus Multiple Arterial Grafts trial will further test the multiple arterial graft hypothesis. Trial registration This trial is registered as ISRCTN46552265. Funding This project was funded by the British Heart Foundation, the UK. Medical Research Council and the National Institute for Health and Care Research (NIHR) Efficacy and Mechanism Evaluation programme and will be published in full in Efficacy and Mechanism Evaluation; Vol. 10, No. 7. See the NIHR Journals Library website for further project information.

Bilateral internal thoracic artery versus single internal thoracic artery plus radial artery: A double meta-analytic approach

ObjectivesWe explored the current evidence on the best second conduit in coronary surgery carrying out a double meta-analysis of propensity score matched or adjusted studies comparing bilateral internal thoracic artery (BITA) versus single internal thoracic artery plus radial artery. MethodsPubMed, Embase, and Google Scholar were searched for propensity score matched or adjusted studies comparing BITA versus single internal thoracic artery plus radial artery. The end point was long-term mortality. Two statistical approaches were used: the generic inverse variance method and the pooled meta-analysis of Kaplan–Meier-derived individual patient data. ResultsTwelve matched populations comparing 6450 patients with BITA versus 9428 patients with single internal thoracic artery plus radial artery were included in our meta-analysis. The generic inverse variance method showed a statistically significant survival benefit of the BITA group (hazard ratio, 0.84; 95% CI, 0.74-0.95; P = .04). The Kaplan-Meier estimates of survival at 1, 5, 10, and 15 years of the BITA group were 97.0%, 91.3%, 80.0%, and 68.0%, respectively. The Kaplan-Meier estimates of survival at 1, 5, 10, and 15 years of the single internal thoracic artery plus radial artery group were 97.3%, 91.5%, 79.9%, and 63.9%, respectively. The Kaplan–Meier-derived individual patient data meta-analysis applied to very long follow-up time data, showed that BITA provided a survival benefit after 10 years from surgery (hazard ratio, 0.77; 95% CI, 0.63-0.94; P = .01). No differences in terms of survival between the 2 groups were detected when the analysis was focused on the first 10 years of follow-up (hazard ratio, 0.99; 95% CI, 0.91-1.09; P = .93). ConclusionsThe present meta-analysis suggests that double internal thoracic artery may provide, compared with single internal thoracic artery plus radial artery, a statistically significant survival advantage after 10 years of follow-up, but not before. Video Abstract [Display omitted]

STS Adult Cardiac Surgery Database: 2021 Update on Outcomes, Quality, and Research

The Society of Thoracic Surgeons Adult Cardiac Surgery Database is the most mature and comprehensive cardiac surgery database. It has been the foundation for quality measurement and improvement activities in cardiac surgery, facilitated the generation of accurate risk adjusted performance benchmarks and serves as a platform for novel research. Recent enhancements have added to the database's functionality, ease of use, and value to multiple stakeholders. This report is the sixth in a series of annual reports that provide updated volumes, outcomes, database-related developments, quality improvement initiatives, and research summaries using the Adult Cardiac Surgery Database in the past year.

Bilateral internal thoracic artery grafting in haemodialysis patients with diabetic nephropathy.

To compare postoperative outcomes in patients with diabetic nephropathy receiving haemodialysis and undergoing isolated coronary artery bypass grafting (CABG) using bilateral or single skeletonized internal thoracic artery (ITA). Among 1441 consecutive patients undergoing isolated CABG between 2002 and 2019 at our university hospital, we retrospectively analysed data for 107 patients with diabetic nephropathy receiving haemodialysis. After inverse probability of treatment weighting, we found no statistically significant differences regarding patients' preoperative characteristics. All patients underwent myocardial revascularization using the off-pump technique. There was no statistical significance in postoperative deep sternal wound infection (P = 0.902) and 30-day mortality (P = 0.755). However, the bilateral ITA group had a lower rate of postoperative stroke versus the single group (0% vs 5.5%, respectively; P = 0.021). Follow-up was completed in 95.3% (102/107) of the patients, and the mean follow-up duration was 3.3 years. Thirty-eight deaths occurred in the bilateral ITA group and 18 in the single ITA group. There was no significant difference in all-cause death (P = 0.558) and cardiac death rates (P = 0.727). Multivariable Cox regression models showed that the independent predictors of all-cause death were age [hazard ratio (HR) 1.031; P = 0.010], previous percutaneous intervention (HR 1.757; P = 0.009) and gastroepiploic artery grafting (HR 0.582; P = 0.026). Bilateral ITA grafting in patients with diabetic nephropathy receiving haemodialysis did not improve mid-term outcomes.

Bilateral internal thoracic artery grafting in elderly patients: Any benefit in survival?

The purpose of the present study was to compare survival outcomes in propensity score-matched patients aged 70years or greater receiving a bilateral internal thoracic artery graft with patients receiving a single internal thoracic artery graft. Among 4083 consecutive patients with isolated coronary artery bypass grafting who underwent operation between January 2001 and December 2018, we identified 1300 patients aged 70years or greater; of these, 968 received a bilateral internal thoracic artery (bilateral internal thoracic artery group) and 332 received a single internal thoracic artery (single internal thoracic artery group). Propensity score matching was used to reduce the preoperative patient differences. The 10-year survival and postoperative complications were compared between the 2 groups. A Kaplan-Meier curve at 10years of follow-up showed that crude survival was significantly superior in patients with bilateral internal thoracic artery grafts than in patients with single internal thoracic artery grafts (67.0%±2.5% vs 56.0%±3.4%, respectively; P<.016). In the actuarial survival, estimates for propensity score-matched patients with a bilateral internal thoracic artery showed a significantly higher rates of survival than patients with a single internal thoracic artery by the end of follow-up (66.0%±5.3% vs 53.0%±3.9%, respectively; hazard ratio, 0.64; 95% confidence interval, 0.44-0.94; P=.022, univariable Cox Model and multivariable analysis hazard ratio, 0.66; 95% confidence interval, 0.45-0.97; P=.036 Cox model). Postoperative complications were all similar between the single internal thoracic artery and bilateral internal thoracic artery groups. The use of bilateral internal thoracic artery grafting in older patients improves 10-year survival, with similar postoperative morbidity. This surgical technique might have beneficial effects in survival in patients aged more than 70years. Its use could be considered more frequently.

POST CABG SURGERY PAIN WITH THE USE OF SKELETONIZED VERSUS PEDICLED TECHNIQUE OF INTERNAL THORACIC ARTERY HARVESTING

Objective: To document post coronary artery bypass graft (CABG) surgery painwith the use of skeletonized technique versus pedicled technique of internalthoracic artery (ITA) harvesting in our population. Methodology: A cross sectional study was done from February 2014 toSeptember 2017. Patients who underwent elective on-pump coronary arterybypass graft surgery were included in the study. Patients ware subjected to twodifferent techniques for CABG surgery. Postoperatively CABG surgery painintensity was scored prior to discharge and at 01 month follow-up on a visualanalogue scale (VAS) ranging from 0 to 10. Chi square statistical test was utilized(p 0.05), whereas the Visual Analogue Score was significantlylower in the skeletonized left ITA group (p≤0.05) at one month follow up. Conclusion: There is decreased post CABG surgery pain with the use ofskeletonized technique of internal thoracic artery harvesting compared topedicled technique.

Is internal thoracic artery resistant to reperfusion injury? Evaluation of the storage of free internal thoracic artery grafts

ObjectivesThe in situ internal thoracic artery (ITA) is recognized as the best conduit for coronary artery bypass surgery. The ITA—if it is used as an in situ graft—has a much higher late patency rate than any other arterial graft, including a free ITA graft. We sought to determine if the use of the ITA as an in situ/free graft and its storage in preservation solutions, have an effect on endothelial function. MethodsThe ITA was harvested as either a free or in situ graft in a porcine model. Free grafts were stored in different preservation solutions (saline, Custodiol and Tiprotec [both Köhler Chemie GmbH, Bensheim, Germany]). The ITA was anastomosed off pump to the left anterior descending artery (as in situ/free graft). Freshly harvested ITA served as a control. After 2 hours of reperfusion, the implanted grafts were harvested. The assessment of endothelial function, histopathological analysis, and gene expression were performed. ResultsEndothelial function and integrity were severely impaired after reperfusion in the free ITA groups, however, it was partially preserved in the Tiprotec group. Reperfusion injury resulted in increased nitro-oxidative stress, DNA breakage, vascular cell adhesion protein 1, intercellular adhesion molecule-1, and caspase-3 scores, and a decreased endothelial nitric oxide synthase score in the free ITA groups. The in situ ITA graft showed no signs of injury. mRNA levels were significantly altered among the groups. ConclusionsAn early, severe endothelial dysfunction of the stored, free ITA as described, could be completely prevented by the use of an in situ ITA graft. Tiprotec might be a feasible option for storage of free arterial grafts during coronary artery bypass grafting.

Saphenous vein versus right internal thoracic artery as a Y-composite graft: Five-year angiographic and clinical results of a randomized trial

ObjectivesWe compared the 5-year graft occlusion rates and midterm clinical outcomes of saphenous vein composite grafts with those of right internal thoracic artery composite grafts in patients who were enrolled in the SAphenous VEin versus Right Internal Thoracic Artery as a Y-Composite Graft trial. MethodsOf 224 eligible patients with multivessel coronary artery disease who were randomized to undergo off-pump revascularization using the saphenous vein (saphenous vein group, n = 112) or right internal thoracic artery (right internal thoracic artery group, n = 112) as Y-composite grafts based on the in situ left internal thoracic artery from September 2008 to October 2011, 219 patients (saphenous vein group, n = 109; right internal thoracic artery group, n = 110) entered the analysis. A third limb conduit to lengthen the graft limb for complete revascularization was used in 47 patients (saphenous vein group vs right internal thoracic artery group, 8 vs 39). Postoperative 5-year (61.7 ± 5.2 months) angiograms were performed in 186 patients (84.9%; saphenous vein group = 95; right internal thoracic artery group = 91). Follow-up was complete in 97.7% (214/219) of patients with a median follow-up of 80.7 months. ResultsThe overall graft occlusion rate was 3.6% at 5 years (3.5% in the saphenous vein group vs 3.7% in the right internal thoracic artery group, P = .910). The 5-year occlusion rate of the second limb conduits in the saphenous vein group was 4.3% and was noninferior to that of the right internal thoracic artery group (2.4%) within the 95% 2-sided confidence interval of −1.4% to 5.2% (P < .001 for noninferiority). No statistically significant differences were found in the overall survival (P = .439) and the freedom from major adverse cardiac and cerebrovascular event rates (P = .354) at 5 and 8 years between the 2 groups. ConclusionsThe saphenous vein composite grafts were noninferior to the right internal thoracic artery composite grafts in terms of 5-year graft occlusion rates and midterm clinical outcomes.

Current trends in bilateral internal thoracic artery use for coronary revascularization: Extending benefit to high-risk patients

BackgroundWe sought to identify the trends in bilateral internal thoracic artery use and determine the degree to which the survival advantage of bilateral internal thoracic artery revascularization persists among perceived “high-risk” patients, compared with the use of left internal thoracic artery alone. MethodsA retrospective review was conducted of patients who underwent isolated coronary artery bypass grafting for multivessel coronary artery disease at the Mayo Clinic between January 2000 and December 2015. Propensity score matching was performed between patients with bilateral internal thoracic artery and left internal thoracic artery alone grafts (1011 matched pairs). Effect of bilateral internal thoracic artery use on survival in “high-risk” patients (ejection fraction <40%, body mass index ≥30, age ≥70 years, diabetes, chronic lung disease, cerebrovascular accident) was evaluated. ResultsA total of 6468 isolated coronary artery bypass grafts were performed (5431 using left internal thoracic artery alone, 1037 using bilateral internal thoracic artery). There was an increasing trend in bilateral internal thoracic artery use (P value for linear trend = .005), with the percentage of coronary artery bypass grafting cases with bilateral internal thoracic artery doubling over the last 4 years (13% in 2012 to 27% in 2015). Propensity-matched comparisons showed a survival advantage for bilateral internal thoracic artery (hazard ratio, 0.81; 95% confidence interval, 0.66-0.99; P = .043). Risk of deep sternal wound infection, although higher in the bilateral internal thoracic artery group, was not significant (1.2% vs 0.5%; P = .088). None of the “high-risk” subsets of patients showed an adverse effect of bilateral internal thoracic artery on survival. ConclusionsBilateral internal thoracic artery use in coronary artery bypass grafting is increasing over time. There is a consistent survival benefit with bilateral internal thoracic artery use, extending to patients with higher-risk comorbidities, suggesting the need for further expansion in use of this technique.

Incidence and clinical implications of intraoperative bilateral internal thoracic artery graft conversion: Insights from the Arterial Revascularization Trial

BackgroundThe Arterial Revascularization Trial has been designed to answer the question whether the use of bilateral internal thoracic arteries can improve 10-year outcomes when compared with single internal thoracic arteries. In the Arterial Revascularization Trial, a significant proportion of patients initially allocated to bilateral internal thoracic arteries received other conduit strategies. We sought to investigate the incidence and clinical implication of bilateral internal thoracic artery graft conversion in the Arterial Revascularization Trial. MethodsAmong patients enrolled in the Arterial Revascularization Trial (n = 3102), we excluded those allocated to single internal thoracic arteries (n = 1554), those who did not undergo surgery (n = 16), and those who underwent operation but withdrew after randomization (n = 7). Propensity score matching was used to compare converted versus nonconverted bilateral internal thoracic artery groups. ResultsA total of 1525 patients were operated with the intention to receive bilateral internal thoracic artery grafting. Of those, 233 (15.3%) were converted to other conduit selection strategies. Incidence of conversion largely varied across 131 participating surgeons (from 0% to 100%). The most common reason for bilateral internal thoracic artery graft conversion was the evidence of at least 1 internal thoracic artery that was not suitable, which was reported in 77 cases. Patients with intraoperative bilateral internal thoracic artery graft conversion received a lower number of grafts (2.95 ± 0.84 vs 3.21 ± 0.74; P < .001). However, the hospital mortality rate was comparable to that of those who did not require bilateral internal thoracic artery graft conversion (0% vs 1.6%; P = .1), as well as the incidence of major complications. At 5 years, we found a nonsignificant excess of deaths (11.9% vs 8.4%; P = .1) and major adverse events (17.1% 13.2%; P = .1) mainly driven by an excess of revascularization in patients requiring conversion. ConclusionsThe incidence of intraoperative bilateral internal thoracic artery graft conversion is not infrequent. Bilateral internal thoracic artery graft conversion is not associated with increased operative morbidity, but its effect on late outcomes remains uncertain.

Double versus single internal thoracic artery in coronary artery bypass grafting: role in sterna wound healing

Objective To investigate the effect of double versus single internal thoracic artery on sterna wound healing in coronary artery bypass grafting (CABG). Methods Patients undergoing CABG were randomly divided into experimental group (double internal thoracic artery group) and control group (single internal thoracic artery group) according to the number of internal thoracic artery used in operations. Experimental group: skeletonized double internal mammary arteries were harvested in all 50 cases (37 males and 13 females). Control group: skeletonized left internal mammary artery was harvested in all 50 cases (34 males and 16 females). Sterna wound healing and post-operational complications were observed. Results The incidence of poor sterna wound healing and volume of drainage after operation in the experimental group were more than those in the control group [volume of drainage on the first day: (350.67±56.86)ml vs (240.72±48.35)ml; total volume of drainage: (595.65±102.35)ml vs (398.85±75.84)ml; poor sterna wound healing rate: 20% vs 0; P<0.05 or P<0.01]. The sterna wound healing rate of high-risk patients between two groups had significant difference (8 cases vs 0 case, P<0.05). Conclusions Compared to the single internal mammary artery grafting, the double internal mammary artery grafting increased the risk of sternal wound healing. Key words: Coronary artery bypass/MT; Mammary arteries/SU; Sternum/IN/SU; Fracture healing

Sequential Internal Thoracic Artery Bypass Is Safe but Does Not Improve Survival

The benefit of adding an internal thoracic artery (ITA) sequential bypass to single or bilateral ITA graft to improve arterial revascularization is not established. The goal of this study is to evaluate the safety and the potential benefit of ITA sequential bypass in coronary artery surgery. We retrospectively reviewed a cohort of 1,400 consecutive, prospectively followed patients who underwent off-pump coronary artery bypass surgery for multivessel disease between September 1996 and November 2007 at the Montreal Heart Institute. Among them, 1,315 (93.9%) patients had 2- or 3-vessel disease and received at least 1 ITA graft. The following 4 groups were investigated: group 1, single ITA grafting alone (n=758); group 2, single ITA+sequential grafting (n=151); group 3, bilateral ITA grafting alone (n=308); and group 4, bilateral ITA+sequential grafting (n=98). Mean follow-up was 63±33 months and completed in 97% of the cohort. Single ITA patients were older, had more diabetes, chronic obstructive pulmonary disease, peripheral vascular disease, emergency surgery, and heart failure. The rates of complete revascularization, conversion to cardiopulmonary bypass, perioperative mortality, and myocardial infarction were similar in all groups. After correcting for risk factors, better overall, cardiac, and major adverse cardiac event (MACE)-free survival were observed in the bilateral ITA groups compared with the single ITA groups. Adding sequential ITA bypass grafting did not significantly impact survival or MACE-free survival. In our series, bilateral ITA grafting improved overall and MACE-free survival. Adding a sequential ITA bypass grafting was safe but did not add significant benefit in off-pump coronary artery bypass surgery.

Bilateral internal thoracic artery grafting for peripheral arterial disease patients

Peripheral arterial disease (PAD) is known to have a poor prognosis. Some reports have also described poor late results after coronary artery bypass grafting (CABG). However, there have been few reports about whether bilateral internal thoracic artery grafting improves the long-term survival of PAD patients after CABG. We performed this study to clarify whether or not this is the case. One hundred and thirty-six PAD patients who underwent elective CABG with two or more grafts were enrolled in this study. Patients were divided into two groups, 71 patients in the bilateral internal thoracic artery (BITA) group and 65 patients in the single internal thoracic artery (SITA) group. The maximum follow-up period was 19 years, with a mean of 5.7 ± 4.4 years. We investigated the long-term results based on three factors; survival, freedom from cardiac death, and freedom from cardiac events. The 3-, 5- and 10-year survival rates in the BITA group were 83.0, 74.2, and 43.1%, respectively. And those in the SITA group were 79.4, 67.7, and 32.3%, respectively. There were no significant differences between the two groups (p = 0.5843). There were also no statistically significant differences between the two groups in terms of the freedom from cardiac death (p = 0.8589) or in the freedom from cardiac events (p = 0.9445). No long-term advantage was observed for CABG with BITA in comparison to SITA alone in patients with PAD.

Is the second internal thoracic artery better than the radial artery in total arterial off-pump coronary artery bypass grafting? A propensity score–matched follow-up study

The aim of our study was to evaluate the long-term outcome of patients exclusively undergoing total arterial revascularization off-pump coronary artery bypass grafting and to compare the performance of the radial artery and the right internal thoracic artery as a second conduit. We studied a consecutive series of 1700 patients undergoing off-pump coronary artery bypass grafting, receiving a radial artery or right internal thoracic artery as a second graft for total arterial revascularization, between 2003 and 2010. A total of 1447 patients (85.11%) received bilateral internal thoracic artery grafting, and 253 patients (14.89%) received left internal thoracic artery and radial artery grafting. A propensity score-matched analysis was performed to compare the 2 groups, bilateral internal thoracic artery and left internal thoracic artery and radial artery, relative to overall survival, morbidity, and combined end points event-free survival. Hazard ratios (HRs) and their 95% confidence intervals (CIs) were estimated by Cox regression. In the full unmatched patient population, the postoperative survival (HR, 0.59; 95% CI, 0.38-0.92; P = .021), incidence of reintervention/readmission (HR, 0.42; 95% CI, 0.28-0.61; P < .001), and combined end points (HR, 0.47; 95% CI, 0.35-0.63; P < .001) were significantly better in the bilateral internal thoracic artery group. In the propensity score-matched patient population, the incidence of reintervention/readmission (HR, 0.40; 95% CI, 0.18-0.88; P = .02) and combined end points (HR, 0.54; 95% CI, 0.32-0.92; P = .02) were significantly better in the bilateral internal thoracic artery group compared with the left internal thoracic artery-radial artery group. The results of our study provide evidence for the superiority of the right internal thoracic artery graft compared with the radial artery as a second conduit in total arterial revascularization off-pump coronary artery bypass grafting.

Twenty-five-year outcomes after multiple internal thoracic artery bypass

Coronary artery bypass grafting with multiple internal thoracic artery grafts is currently controversial. This study assessed single institutional outcomes with multiple internal thoracic artery grafting for guidance with future clinical decisions. In 19,482 patients undergoing multivessel coronary artery bypass grafting (1984-2009), baseline characteristics were recorded in a prospective databank, and follow-up was obtained by questionnaires, phone contact, or National Death Index. Outcomes examined were subsequent myocardial infarction, percutaneous coronary intervention, reoperative coronary artery bypass grafting, all-cause death, and a composite of the 4. Three groups were defined: (1) no internal thoracic artery graft (1874/19,482 or 9%); (2) single internal thoracic artery grafts and adjunctive venous conduits (single internal thoracic artery; 16,881/19,482 or 87%); and (3) multiple internal thoracic artery grafts (728/19,482 or 4%). Multivariable Cox modeling adjusted for differences in baseline characteristics, and comparisons were performed using area under the curve analysis. Differences in baseline characteristics for the no internal thoracic artery graft, single internal thoracic artery, and multiple internal thoracic artery groups were as follows: median age 66, 64, and 59 years, respectively; congestive heart failure 22%, 18%, and 13%, respectively; ejection fraction 0.50, 0.52, and 0.51, respectively; reoperation 10%, 3%, and 7%, respectively; diabetes 27%, 30%, and 15%, respectively; and female gender 33%, 28%, and 20%, respectively. No differences existed in the median number of diseased vessels (3, 3, and 3, respectively) or number of grafts per patient (3, 3, and 3, respectively). Composite outcome improved with increasing internal thoracic artery grafts, whether assessing unadjusted or risk-adjusted data. Compared with no internal thoracic artery graft, the adjusted hazard ratio was 0.79 (confidence interval, 0.74-0.83) for single internal thoracic artery grafting and 0.70 (confidence interval, 0.62-0.80) for multiple internal thoracic artery grafting (both P < .001), reducing risk by 21% and 30%, respectively. This study confirms improved patient outcomes with multiple internal thoracic artery grafting, achieving half again as much benefit as single internal thoracic artery grafting alone. The data suggest that increasing application of multiple internal thoracic artery grafting should be encouraged to mitigate the inherent risks and costs of long-term cardiac events.

A randomized comparison of the Saphenous Vein Versus Right Internal Thoracic Artery as a Y-Composite Graft (SAVE RITA) trial: Early results

The Saphenous Vein Versus Right Internal Thoracic Artery as a Y-Composite Graft trial was designed to evaluate the saphenous vein compared with the right internal thoracic artery as a Y-composite graft anastomosed to the side of the left internal thoracic artery. In this early analysis, we compared early angiographic patency rates and clinical outcomes. From September 2008 to October 2011, 224 patients with multivessel coronary artery disease were randomized prospectively to undergo off-pump revascularization using the saphenous vein group (n = 112) or the right internal thoracic artery group (n = 112) as Y-composite grafts. Early postoperative (1.4 ± 1.1 days) angiographic patency and clinical outcomes were compared. There was 1 operative death in the right internal thoracic artery group. No statistically significant differences in postoperative morbidities, including atrial fibrillation and acute renal failure, were observed between the groups. The number of distal anastomoses using the side-arm Y-composite graft (saphenous vein vs right internal thoracic artery) were 2.3 ± 0.8 and 1.9 ± 0.7 in the saphenous vein and right internal thoracic artery groups, respectively (P < .001). A third conduit was used in 44 patients (saphenous vein group vs right internal thoracic artery group, 4/109 vs 40/110; P < .001) to extend the side-arm Y-composite graft for complete revascularization. Early angiography demonstrated an overall patency rate of 99.4% (771 of 776 distal anastomoses). Patency rates of the side-arm Y-composite graft (saphenous vein vs right internal thoracic artery) were 98.8% (245 of 248) and 99.5% (207 of 208) in the saphenous vein and right internal thoracic artery groups, respectively (P = .629). A third conduit was needed to extend the right internal thoracic artery composite graft and reach the target vessels in 36.4% (40/110) of the patients. The saphenous vein composite graft was comparable with the right internal thoracic artery composite graft in terms of early angiographic patency and clinical outcomes.

The “no-dissection” technique is safe for reoperative aortic valve replacement with a patent left internal thoracic artery graft

Management of a patent left internal thoracic artery graft during reoperation is controversial. The "no-dissection" technique avoids dissection and clamping of the left internal thoracic artery graft, and myocardial protection is achieved using adjunctive systemic hypothermia and hyperkalemia. We compared the postoperative outcomes after isolated reoperative aortic valve replacement in patients with previous coronary artery bypass grafting with a patent left internal thoracic artery graft using a no-dissection technique with the outcomes of patients with previous coronary artery bypass grafting without a left internal thoracic artery graft. The outcomes were analyzed for patients who underwent isolated reoperative aortic valve replacement with previous coronary artery bypass grafting from January 1, 2002, to June, 30, 2011. Patency of the left internal thoracic artery was confirmed using either coronary angiography or computed tomography angiography. The patent left internal thoracic artery group did not undergo dissection or clamping of the left internal thoracic artery graft, and myocardial protection was obtained using systemic hypothermia and hyperkalemia. The no left internal thoracic artery group underwent isolated aortic valve replacement with previous coronary artery bypass grafting but had no left internal thoracic artery graft. A total 174 patients were identified for the patent left internal thoracic artery group and 26 for the no left internal thoracic artery group. The perfusion and crossclamp times were similar. No differences were seen between the 2 groups in operative mortality (6.9% vs 7.7%, P = 1.00). The complication rates were similar, and the peak creatine kinase-MB values within 24 hours of surgery were not significantly different between the 2 groups (median, 27.4 vs 29 μ/mL; P = .72). Reoperative aortic valve replacement in patients with previous coronary artery bypass grafting and a patent left internal thoracic artery graft can be performed safely without dissection or clamping of the left internal thoracic artery using systemic hyperkalemia and hypothermia. We believe this method prevents unnecessary injury during dissection of the left internal thoracic artery graft.

Angiographic predictors of 3-year patency of bypass grafts implanted on the right coronary artery system: A prospective randomized comparison of gastroepiploic artery, saphenous vein, and right internal thoracic artery grafts

Saphenous vein, in situ right gastroepiploic artery, and right internal thoracic artery grafts are routinely used to revascularize the right coronary artery. Little is known about the predictive value of objective preoperative angiographic parameters on midterm graft patency. We prospectively enrolled 210 consecutive patients undergoing coronary revascularization. Revascularization of the right coronary artery was randomly performed with the saphenous vein grafts in 81 patients and the right gastroepiploic artery in 92 patients. During the same study period, 37 patients received right coronary artery revascularization with the right internal thoracic artery used in a Y-composite fashion. All patients underwent a protocol-driven coronary angiogram 3 years after surgery. Preoperative angiographic parameters included minimum lumen diameter percent stenosis measured by quantitative angiography. A graft was considered "not functional" with patency scores of 0 to 2 and "functional" with patency scores of 3 or 4. Angiographic follow-up was 100% complete. A significant difference in the distribution of flow patterns was observed in the 3 groups. In multivariate analysis, the use of a saphenous vein graft was associated with superior graft functionality compared with the other conduits (odds ratio, 6.1; 95% confidence interval, 2.4-15). Graft function was negatively influenced by the minimum lumen diameter (odds ratio, 0.11; confidence interval, 0.05-0.25). In the right gastroepiploic artery and right internal thoracic artery groups, the proportion of functional grafts was higher when the minimum lumen diameter was below a threshold value in the third minimum lumen diameter quartile (0.64-1.30 mm). Preoperative angiography predicts graft patency in the right gastroepiploic artery and right internal thoracic artery, whereas the flow pattern in saphenous vein grafts is significantly less influenced by quantitative angiographic parameters.

Artéria torácica interna esqueletizada está associada a menores taxas de mediastinite em idosos submetidos à cirurgia de revascularização miocárdica

Mediastinitis is a serious complication of median sternotomy and is associated to significant morbidity and mortality. The aim of this study is to identify which option of harvesting internal thoracic artery (ITA), pedicled or skeletonized, is associated with lower rates of mediastinitis after coronary artery bypass grafting surgery (CABG) in elderly, in the Division of Cardiovascular Surgery of PROCAPE. Retrospective study of 160 elderly who underwent consecutive CABG between May 2007 and June 2011. Eleven preoperative variables, four intraoperative variables and eight postoperative variables possibly involved in the development of postoperative mediastinitis were evaluated between two groups: CABG with skeletonized ITA (n=80) and pedicled ITA (n=80). Univariate and multivariate logistic regression analyses were applied. The incidence of mediastinitis was 6.8% (n=11), with a lethality rate of 54.5% (n=6). The skeletonized ITA group were more exposed than pedicled ITA group to obesity (n=12 vs. n=4; 15% vs. 5%; P=0.035) and multiple transfusions (n=25 vs. n=11; 31.2% vs. 13.7%; P=0.008). The pedicled ITA group presented a greater risk of mediastinitis after CABG than skeletonized ITA group (n=10 vs. n=1; 12.5% vs. 1.2%; Unadjusted OR 11.3; 95% CI 1.4 - 241.5; P=0.008). In multivariate analysis, this difference maintained statistically significant (Adjusted OR 5.2; 95% CI 1.5-495.8; P=0.012), being considered an independent association. We suggest that elderly should be considered for strategies to minimize risk of infection. In elderly that undergo unilateral ITA, the problem seems to be related to how ITA is harvested. Elderly should always be considered for use of skeletonized ITA.

Efficacy of Bilateral Internal Thoracic Artery Grafting in Patients With Chronic Kidney Disease

This study compared short-term and long-term outcomes in propensity score-matched patients with chronic kidney disease receiving bilateral internal thoracic artery (ITA) or single ITA grafting and assessed any benefit of bilateral ITA grafting for survival. Among 656 consecutive patients undergoing isolated coronary artery bypass grafting (99.1% by off-pump technique) between 2002 and 2008, 361 had chronic kidney disease with no history of dialysis. After excluding 10 patients who would not be potential candidates for bilateral ITA grafting because they were aged older than 85 years and 15 who had only one target vessel at the left coronary area, we identified 157 propensity score-matched pairs. Propensity scores were created based on 13 preoperative factors (C statistics, 0.787). During a mean observation of 2.9 years, the rates of overall death and cardiac death (myocardial infarction, heart failure, and sudden death) in the bilateral ITA group were significantly lower than those in the single ITA group (5.1% vs 15.9%, p=0.01; 1.3% vs 8.3%, p=0.01). In multivariate Cox models including bilateral ITA grafting and all other potential predictors, bilateral ITA grafting was significantly associated with a lower risk for overall death (hazard ratio, 0.29; 95% confidence interval, 0.10 to 0.89; p=0.03) and cardiac death (hazard ratio, 0.14; 95% confidence interval, 0.03 to 0.63; p=0.02). Among patients with chronic kidney disease, bilateral ITA grafting provides better long-term survival than single ITA grafting.