Bilateral Internal Thoracic Artery Grafting Research Articles

Expert Consensus Document. Third Universal Definition of Myocardial Infarction

Although coronary artery bypass grafting using bilateral internal thoracic arteries (ITA) maximizes long-term survival, knowledge of the effect of different right ITA (RITA) inflow configurations on graft patency is limited. We have compared RITA occlusion among these configurations and identified its risk factors while adjusting for outflow coronary target location.From January 1972 to January 2016, of 7092 patients undergoing bilateral ITA grafting at a single center, 1331 received one ITA to the left anterior descending coronary artery and had one or more evaluable postoperative coronary angiograms: 835 (63%) in situ, 496 free RITA grafts (311 [63%] originating from aorta; 98 [20%] left ITA [LITA], 76 [15%] saphenous vein graft, 11 [2%] radial graft). RITA occlusion reported on 1983 angiograms performed a median of 5.8 years later was estimated using nonlinear mixed-effects longitudinal modeling.RITA patency was 90% at 1 year, 87% at 5 years, and 86% at 10 and 15 years. At 15 years, in situ RITA patency was 91% and free RITA patency from aorta was 91%, LITA 89%, and saphenous vein graft 77%. After adjusting for coronary target location and degree of stenosis, occlusion was similar in free RITAs from aorta (P = .15), LITA (P = .4), saphenous vein grafts (P = .13), and in situ RITAs. However, RITAs grafted to the left anterior descending coronary artery had fewer occlusions (P < .001), with patency similar to LITAs.Among patients with bilateral ITA grafting requiring interval coronary angiography, long-term RITA patency was high and independent of its inflow configuration. Therefore, priority should be a RITA configuration optimizing its reach to important coronary targets, including the left anterior descending coronary artery.

Coronary Revascularization Using Bilateral Internal Thoracic Arteries: Safe with Skeletonization?

Substantial evidence exists to support a long-term survival benefit with bilateral internal thoracic artery (BITA) revascularization in coronary artery bypass grafting. However, this technique remains grossly underutilized worldwide and especially in the United States. In this review, we discuss evidence for the advantages of BITA grafting as well as the associated the risk of sternal wound complications. We then review a growing body of literature that suggests ‘skeletonization’ of the internal thoracic artery during harvest confers a protective benefit against sternal wound infection in patients receiving BITA.

Invited Commentary

Internal thoracic arteries are considered the optimal bypass conduit because they rarely develop atherosclerosis and mature to adjust their flow to the requirements of the myocardium they perfuse. The use of bilateral internal thoracic arteries (BITA) grafts improves long-term survival and lowers the rate of cardiovascular events [1]. Multiple graft configurations have been described to use both ITAs, including in situ and free grafts, and patency rates for both LITA and RITA have been shown to be equivalent for specific myocardial territories, and better than radial or saphenous vein grafts [2].

Why Did You Not Use Both Internal Thoracic Arteries?

That is the question every cardiologist should ask if the patient he or she has referred for primary surgical coronary revascularization returns from the operating room with a single internal thoracic artery graft. There is a substantial body of evidence demonstrating that the majority of coronary bypass patients benefit more when coronary artery bypass graft (CABG) surgery is performed with both internal thoracic artery conduits rather than just one.1–4 However, only 4.4% of primary isolated CABG cases in the 2011 Society of Thoracic Surgeons National Adult Cardiac Surgery Database received bilateral internal thoracic artery (BITA) grafting.5 There are several putative reasons for this failure of adoption, but referring cardiologists and patients should demand better. Article see p 2935 Why are American surgeons doing so few BITA grafts? Fundamentally, U.S. surgeons are responding to their practice environment, especially to a fear of deep sternal wound infection in an increasingly obese, diabetic population of patients. The surgeon pays a large and immediate political price for a deep sternal wound infection and receives relatively little credit for the extra years that BITA grafting adds to a patient's life in the future. There is also a relative financial disincentive to perform BITA grafting: incremental payment for the second internal thoracic artery graft is small considering the extra time required in the operating room. Moreover, the Centers for Medicare and Medicaid Services no longer reimburse for extra care necessary for treatment of mediastinitis after cardiac surgery, because this is now deemed a never event. Thus, surgeons, who are increasingly employed by hospitals and hospital systems, are under intense pressure to perform CABG surgery that is safe and cost-effective according to short-term metrics. Any perceived tradeoff, however small or misinformed, between the long-term benefit of BITA grafting and short-term risk of mediastinitis, …

Invited Commentary

Invited Commentary

Sequential In Situ Left Internal Thoracic Artery Grafting to the Circumflex and Right Coronary Artery Areas

Several bilateral internal thoracic artery (ITA) grafting patterns have been proposed to enhance 3-vessel coronary artery revascularization. We present the outcomes of sequential in situ left ITA grafting to the circumflex and right coronary artery (RCA) areas. Between January 2001 and September 2007, 102 patients with 3-vessel coronary artery disease underwent arterial myocardial revascularization with bilateral in situ ITA grafts. The circumflex and distal RCA branches were revascularized sequentially with the left ITA. The left anterior descending artery area was grafted with the right ITA. Ninety-nine patients (97.0%) were monitored for 37.2 ± 2.9 months, and 77 (75.4%) underwent postoperative coronary imaging after 27.8 ± 5.8 months. The bilateral ITA grafts were 97.1% patent (FitzGibbon grade A+B) overall. The sequential anastomoses of the left ITA to the circumflex and RCA territories were 96.7% patent overall, with competitive flow (FitzGibbon grade B) in 3 patients. The patency rates of sequential anastomoses to the circumflex and RCA branches were 98.0% and 95.0%, respectively. The right posterolateral and right descending posterior artery anastomoses were 91.8% and 100% patent, respectively. The in situ right ITA grafts to the left anterior descending artery area were 98.0% (FitzGibbon grade A+B) patent overall. Angina recurred in 1 patient (0.9%) 6 months after the operation. Percutaneous coronary interventions were performed in 3 patients (3.8%). No cardiac deaths occurred during the follow-up period. Sequential in situ left ITA grafting to the circumflex and RCA areas yields acceptable midterm results in selected patients with 3-vessel disease.

Clinical outcome of arterial myocardial revascularization using bilateral internal thoracic arteries in diabetic patients: a single centre experience

The use of bilateral internal thoracic arteries (BITAs) grafting has been documented to be advantageous over left internal thoracic artery (LITA) grafting. It has been shown to significantly improve clinical outcomes and increase long-term survival in patients with diabetes. However, harvesting BITAs may result in a greater risk of superficial wound infection (SWI) or deep sternal wound infection (DSWI) and cardiovascular complications (major adverse cardiac and cerebrovascular events; MACCE) in such a patient group. The objective of this study was to compare the incidence of SWI or DSWI and cardiovascular events in a series of isolated coronary artery bypass grafting (CABG) patients who underwent BITA grafting vs LITA grafting. A total of 147 patients with coronary artery disease and diabetes underwent isolated CABG at John Paul II Hospital. Of these, 38 procedures were performed using BITA grafting and 109 with LITA-saphenous vein grafting. MACCE were similar in bilateral groups (7.9%--BITA group and 9.2%--LITA group). No significant difference was found in mortality and length of stay between bilateral groups. The MACCE risk factor was age. The incidence of SWI and DSWI and sternal re-fixation did not differ between the BITA or LITA groups (5.2 vs 9.1%, 5.2 vs 7.3% and 5.2 vs 6.4%). The risk factors for DSWI were age (odds ratio 3.47, P = 0.032 for every 10 years) and body mass index >30 kg/m(2). Perioperative complications do not increase with the use of BITAs in this group of diabetic patients. There are no statistically significant differences in the number of superficial or deep wound infections or number of sternal resuturing between the BITA and LITA groups.

Long-term outcomes of patients with diabetes receiving bilateral internal thoracic artery grafts

Bilateral internal thoracic artery (BITA) grafting in patients with diabetes are controversial because of increased risk of sternal infection. On the other hand, patients with diabetes may benefit from BITA grafts because of the associated improved survival. This study evaluated factors affecting early and long-term outcomes for better selection of patients with diabetes for BITA grafts. Between 1996 and 2006, 69 patients with insulin-treated diabetes and 732 with orally treated diabetes received isolated skeletonized BITA grafts. Of these patients, 338 were younger than 65 years, 322 were between 65 and 74 years old, and 141 were 75 years or older. Operative mortality was lower than logistic EuroSCORE-calculated mortality (2.9% vs 7%, P < .001). Predictors of increased mortality were critical preoperative state (P < .001) and age (P = .008). There were 30 cases of sternal infection (3.7%); predictors were reoperation (P < .001), peripheral vascular disease (P = .009), obesity (P = .012), chronic lung disease (P = .009), and female sex (P = .020). Mean follow-up was 8.4 ± 4 years. Kaplan-Meier 10-year survivals were 75%, 59%, and 39% for patients younger than 65, 65 to 74, and at least 75 years, respectively (P < .001). They were better than corresponding Charlson comorbidity index-predicted survivals (36%, 10%, and 3%, respectively; P < .001). Predictors of decreased survival were age (P < .001), congestive heart failure (P < .001), and peripheral vascular disease (P < .001). Off-pump surgery was independently associated with better long-term survival (P = .003). BITA grafts are safe in patients with diabetes. Favorable short- and long-term outcomes outweigh increased sternal infection risk.

EComment. The best graft for the right coronary artery

We read with great interest the paper by Mukherjee et al. [1] After reviewing five articles and due to the lack of studies dealing with long term follow-up, they concluded that the saphenous vein (SV) graft offers superior short and midterm outcomes compared to the right internal thoracic artery (RITA) for the revascularization of the right coronary artery (RCA). However, we believe that there are some issues that need to be addressed. Several papers [2, 3] have established the superiority of the use of bilateral internal thoracic arteries (BITA) to revascularize the left coronary system. Recently, the preliminary results of the randomized ART trial [4] confirmed the safety of using BITA grafts on a routine basis. In this trial, BITA grafts were anastomosed to the two most important left-sided coronary arteries with the supplemental vein or radial artery to the RCA. According to the literature [4, 5], BITA grafts for the left coronary circulation are considered by many as standardized practice. The remaining relevant question is which graft to use for the right coronary system. Although good overall patency for the radial artery (RA) and SV have been described, these are mostly observational studies and their results vary significantly. We are aware of only one randomized trial addressing this topic by comparing the performance of RA versus SV when used to graft the right coronary circulation. The RAPCO trial [5] assigned 621 patients to RA, SV, or free right ITA for the largest coronary target other than the left anterior descending coronary artery. A subgroup analysis [5] of patients over an 8-year period after primary coronary artery bypass graft surgery from RAPCO trial including patients who received a graft to the RCA, posterior descending artery, or left ventricular branch of the RCA using either a RA or SV showed that RA patency was comparable to that of the SV. Accordingly, the authors of RAPCO trial concluded that when considering grafting the RCA or its branches, the selection of best conduit may be made based on other factors. Further randomized controlled trials with longer follow-up periods are required to fully ascertain the best conduit for the RCA. Until then, the SV graft continues to be a routine practice for the revascularization of the RCA. Conflict of Interest: None declared

Off-Pump Bilateral Internal Thoracic Artery Grafting in Right Internal Thoracic Artery to Right Coronary System

Despite many large-volume studies on the use of bilateral internal thoracic artery (ITA) grafts, the benefits of a bilateral (B)ITA graft over a single (S)ITA graft for CABG remain controversial. This study compared midterm outcomes of BITA to SITA grafting in off-pump coronary artery bypass (OPCAB), focusing primarily on the right (R)ITA to right coronary artery (RCA) system. From January 2000 to December 2009, 1,749 patients underwent isolated OPCAB with ITA grafts. Using propensity score matching, 366 BITA patients could be pairwise propensity matched to a SITA patient. We compared midterm survival and major adverse cardiac and cerebrovascular event (MACCE) between the 2 groups. All patients in the BITA group underwent bilateral ITA grafting with the RITA anastomosed to the RCA system. Mean follow-up was 84.46±24.47 months (range, 5 to 120 months). Overall survival at 10 years was not significantly different between the 2 groups (84.6% vs 84.1%; p=0.955). The 10-year cardiac-related death-free rate also did not significantly differ between the groups (90.0% vs 90.9%; p=0.871). The 10-year MACCE-free rate did not significantly differ between the 2 groups (79.7% vs 74.6%; p=0.303). At 10-year follow-up, BITA grafting did not offer advantages over SITA grafting in midterm outcomes, at least in the RITA to RCA system. The BITA grafting was similar to SITA grafting in overall and cardiac survival, and MACCE rates.

Drug-Eluting Stents Compared With Bilateral Internal Thoracic Artery Grafts for Diabetic Patients

Diabetic patients with multivessel coronary artery disease who undergo coronary artery bypass grafting (CABG) or percutaneous coronary interventions (PCI) are at greater risk of late morbidity and mortality than nondiabetic patients. We questioned earlier comparisons of these two approaches that showed no differences in survival rates. This study compares drug-eluting stents (DES) and bilateral internal thoracic artery (BITA) grafting in diabetic patients with multivessel coronary artery disease. All diabetic patients who underwent left-sided arterial revascularization with BITA grafting between January 2002 and May 2006 were evaluated. Their outcomes were compared with those of diabetic patients who underwent PCI with DES (Cypher). The Cox proportional hazards model defined predictors of outcome events after forcing propensity score with patients' characteristics into the model. The outcomes of 226 BITA patients were compared with those of 271 DES patients (mean follow-up 62 months). The 5-year reintervention-free survival (Kaplan-Meier 86% versus 65%, log rank p = 0.000) and major adverse cardiovascular events-free survival (81% versus 54%, p = 0.001) were significantly better in the BITA group. Assignment to the PCI group was associated with decreased adjusted survival (hazard ratio 3.01, 95% confidence interval: 1.59 to 5.73, p = 0.000) and increased risk of target vessel reinterventions (hazard ratio 7.00, 95% confidence interval: 3.1 to 15.70). The adjusted risk of major adverse cardiovascular events increased with the number of DES-treated vessels. This is the first demonstration of significantly better long-term adjusted survival and outcomes of diabetic patients who underwent CABG with BITA grafting compared with diabetic patients who underwent PCI with DES.

Early and long-term outcomes of coronary artery bypass grafting in patients with acute coronary syndrome versus stable angina pectoris

The aim of the present study was to determine the early and long-term outcomes of coronary artery bypass grafting in patients with acute coronary syndrome and stable angina pectoris. From September 2004 to September 2011, 382 patients with acute coronary syndrome (unstable angina pectoris and non-ST-segment elevation myocardial infarction) and 851 patients with stable angina pectoris underwent first-time isolated coronary artery bypass grafting at our institute. The early and long-term outcomes were compared between the 2 groups. Patients with acute coronary syndrome were older, were more likely to be women, had a smaller body surface area, and were more likely to have left main coronary artery disease. In both groups, bilateral internal thoracic artery grafts were used in approximately 89% of the patients, and off-pump techniques in approximately 97% of the patients. The acute coronary syndrome group had a greater operative death rate (2.6% vs 0.1%) and a greater incidence of low output syndrome (3.1% vs 1.2%) and hemodialysis requirement (2.9% vs 1.1%). Multivariate regression analysis demonstrated that age, acute coronary syndrome, lower ejection fraction, and higher creatinine level before surgery were independent predictors of operative death. However, among the hospital survivors, no differences were seen in freedom from all death (85.4% ± 2.5% vs 87.7% ± 2.0%), cardiac death (97.4% ± 0.9% vs 96.5% ± 0.9%), or major adverse cardiac and cerebrovascular events (78.0% ± 2.9% vs 78.1% ± 2.3%) at 7 years between the patients with acute coronary syndrome and stable angina pectoris. Although acute coronary syndrome is an independent predictor of early mortality in patients undergoing coronary artery bypass grafting, the long-term outcomes after surgery were similar between patients with acute coronary syndrome and stable angina pectoris who survived the early postoperative period.

Bilateral Internal Thoracic Artery Grafting Is Associated With Significantly Improved Long-Term Survival, Even Among Diabetic Patients

This study examines if bilateral internal thoracic artery (BITA) grafting provides improved outcomes compared with single internal thoracic artery (SITA) grafting, in the modern era, in which diabetes mellitus and obesity are more prevalent. The Society of Thoracic Surgeons database at a single large academic center was reviewed for all consecutive isolated coronary artery bypass grafting patients with two or more distal anastomoses from January 1, 2002, through December 31, 2010. Propensity-adjusted logistic and Cox regression models were used to estimate the effect of BITA on short-term outcomes and long-term survival for diabetic and nondiabetic patients. A total of 3,527 coronary artery bypass grafting operations (812 BITA, 2,715 SITA) were performed. Fewer BITA than SITA patients had diabetes (28.6% vs 44.7% p<0.001). There was no significant difference in 30-day rates of death, stroke, or myocardial infarction between nondiabetic patients who had BITA vs SITA, or between diabetic patients who had BITA vs SITA. BITA grafting conferred a 35% reduction (95% confidence interval, 12% to 52%, p=0.006) in the long-term hazard of death equally for nondiabetic and diabetic patients (p=0.93). Deep sternal wound infection was more common among diabetic than among nondiabetic patients (1.5% vs 0.7%), but was similar within nondiabetic (1.0% vs 0.6%) and diabetic patients (1.7% vs 1.5%) who had BITA vs SITA. Overall, BITA and SITA patients had similar rates of deep sternal wound infection (1.2% vs 1.0%). BITA grafting confers a long-term survival advantage and should be performed whenever suitable coronary anatomy exists and patient risk factors allow an acceptable risk of deep sternal wound infection.

Reduction of sternal wound infections in diabetic patients undergoing off-pump coronary artery bypass surgery and using modified pedicle bilateral internal thoracic artery harvest technique

We compared sternal wound infections between diabetic patients undergoing off-pump coronary artery bypass surgery using bilateral internal thoracic artery grafting or single internal thoracic artery grafting and nondiabetic patients receiving bilateral internal thoracic artery or single internal thoracic artery grafting using a modified pedicled harvest technique of internal thoracic artery. This retrospective study was conducted to analyze the data from 3072 patients who underwent primary coronary artery bypass surgery using an off-pump technique from August 2004 to October 2010. Of the 1211 diabetic patients, 181 received bilateral internal thoracic artery grafts (group 1) and 1030 received single internal thoracic artery grafts (group 2). Of the 1861 nondiabetic patients, 161 received bilateral internal thoracic artery grafts (group 3) and 1700 received single internal thoracic artery grafts (group 4). The incidence of postoperative sternal wound infections in diabetic patients who received bilateral internal thoracic artery grafting was compared with the incidence in other groups (group 2, 3, and 4). A modified technique of pedicled harvesting of the internal thoracic artery was done in patients receiving bilateral internal thoracic artery grafting, and a standard pedicled harvest was used in patients receiving single internal thoracic artery grafts. No significant differences were present in the preoperative variables among the groups. The observed rate of superficial sternal wound infections in groups 1, 2, 3, and 4 was 1.1% (2 patients), 1.65% (17 patients), 1.86% (3 patients), and 1.65% (28 patients), respectively (P=.9941). Deep sternal infections were observed in 1 (0.55%), 5 (0.48%), 1 (0.62%), and 14 patients (0.82%) in groups 1 through 4, respectively (P=.8380). Multivariate analysis showed that bilateral internal thoracic artery harvesting (P=.889), diabetes mellitus (P=.96), and patient age were not predictors of sternal wound infection. The results of the present study show that there is no increase in the incidence of sternal wound infections in diabetic patients undergoing coronary artery bypass surgery with bilateral internal thoracic artery grafting by using a modified pedicle bilateral internal thoracic artery harvesting technique with sparing of the communicating bifurcation of internal thoracic artery to the chest wall and preservation of pericardiacophrenic artery branch.

Bilateral internal thoracic artery grafting is superior to other forms of multiple arterial grafting in providing survival benefit after coronary bypass surgery

The objective of this study was to examine the effect of arterial grafting on long-term coronary artery bypass grafting mortality. Consecutive coronary artery bypass grafting surgeries performed at a single tertiary care center between 1995 and 2007 were reviewed. Long-term survival was compared among patients according to the type of arterial grafts used: no internal thoracic artery, single internal thoracic artery, single internal thoracic artery with other arterial graft, or bilateral internal thoracic artery. Cox proportional hazard models were generated to examine the association of arterial grafting with mortality. A total of 8264 isolated coronary artery bypass grafting operations were performed and followed for a median time of 4.7 years (interquartile range, 2.1-7.5). A single internal thoracic artery was used in the majority of patients (79%), multiple arterial grafts were used in 24% of patients, and bilateral internal thoracic artery grafts were used in 13% of patients. Patients who received multiple arterial grafts were more likely to be younger, to be male, and to undergo non-urgent surgery. After adjusting for these differences, patients who received bilateral internal thoracic artery grafts were found to have a significant survival advantage when compared with all other patients, including those who received a single internal thoracic artery plus other arterial grafts (hazard ratio, 0.818; confidence interval, 0.672-0.996). Survival at 10 years was 71% for patients with bilateral internal thoracic artery grafts compared with 66% for patients with single internal thoracic artery grafts and 58% for patients with no internal thoracic artery graft. Patients with bilateral internal thoracic artery grafts had significantly better freedom from readmission for acute coronary syndrome (hazard ratio, 0.802; confidence interval, 0.668-0.963). After adjusting for relevant clinical differences, only multiple arterial grafting using the bilateral internal thoracic artery was able to offer a long-term survival advantage over single internal thoracic artery grafting in patients undergoing coronary artery bypass grafting.

Bilateral internal thoracic artery grafting improves long-term survival in patients with reduced ejection fraction: A propensity-matched study with 30-year follow-up

Bilateral internal thoracic artery (BITA) grafting has been shown to improve long-term survival after coronary artery bypass grafting. However, there has been reluctance to use this technique in higher-risk patients. Patients with reduced ejection fraction (EF) have been shown to present a higher operative risk and reduced long-term survival. We studied the perioperative and long-term results of BITA versus single internal thoracic artery grafting (SITA) in a large population of patients with reduced EF in whom BITA grafting was broadly applied. Between February 1972 and May 1994, 4537 consecutive patients in whom EF was recorded underwent SITA (2340) or BITA (2197) grafting. Prospectively collected clinical data recorded EF categorically as less than 0.30 (group I; n = 233), 0.30 to 0.50 (group II; n = 1256), or greater than 0.50 (group III; n = 3048). Multivariable analyses were performed to determine correlates of operative and late mortality. Optimal matching using propensity scoring was used to create matched SITA and BITA cohorts: group I, SITA and BITA, n = 87 each; group II, SITA and BITA, n = 448 each; group III, SITA and BITA, n = 1137 each. Equality of survival distribution was tested by the log-rank algorithm. There was no difference in operative mortality between matched SITA and BITA groups (group I: SITA vs BITA, 10.3% vs 6.9%, P = .418; group II: 4.7% vs 4.5%, P = .873; group III: 3.2% vs 2.0%, P = .086). SITA versus BITA was not a predictor of operative mortality on logistic regression analysis. There was no difference in freedom from any postoperative complication, including sternal wound infection, between matched SITA and BITA groups. Late survival was significantly enhanced with the use of BITA grafting in groups II and III (10- and 20-year survival, SITA vs BITA, in group II: 57.7% ± 0.3% and 19% ± 2.5% vs 62.0% ± 2.3% and 33.1% ± 3.4%, respectively, P = .016; and in group III: 67.1% ± 1.4% and 35.8% ± 1.7% vs 74.6% ± 1.3% and 38.1% ± 2.1%, respectively, P = .012). Likewise, choice of SITA versus BITA was a significant predictor of late mortality on Cox regression in both groups II (P < .007) and III (P < .001). Broadly applied BITA compared with SITA grafting in propensity-matched patients provides enhanced long-term survival with no increase in operative mortality or morbidity for patients with normal and reduced EF. The expanded use of BITA grafting should be seriously considered.

Failed Depiction of Patent Bypass Graft Due to Presence of Large Lateral Costal Artery

We report a rare case of failed depiction of a patent right internal thoracic artery (RITA) to left anterior descending artery (LAD) bypass on 64-slice multidetector row computed tomographic (MDCT) angiography due to the presence of a large lateral costal artery. A 66-year-old male with acute coronary syndrome due to triple vessel disease underwent urgent coronary artery bypass grafting, in which bilateral ITA and saphenous vein grafts were used. Postoperative MDCT angiography showed an occluded RITA-LAD bypass, which was eventually shown to be patent by angiography. Angiography also revealed a large lateral costal artery that was considered to affect the flow to the LAD. Thus, coil embolization of the branch was attempted. However, it was abandoned because the patient suffered from severe back and intercostal pain during balloon occlusion of the lateral costal artery. Postoperative MDCT angiography is not always accurate for the assessment of graft patency in patients with large ITA side branches. In addition, embolization is not always possible because occlusion of this large branch may cause severe pain when its size becomes quite large.

History and Current Status of Robotic Totally Endoscopic Coronary Artery Bypass

Robotic totally endoscopic coronary artery bypass (TECAB) is a minimally invasive endoscopic surgical approach using the daVinci robotic telemanipulation system to perform coronary artery bypass grafting on the arrested or beating heart. It is a procedure that can be a useful alternative to the classic open procedure performed through sternotomy. After extensive modeling in cadavers, the first clinical case was performed in June 1998 placing a left internal thoracic artery graft (LITA) to the left anterior descending artery completely robotically on the arrested heart. During the early and late 2000s, international groups have adopted this evolving technology, which has included iterations such as beating-heart TECAB, use of bilateral ITA grafting and radial artery grafting, as well as 3- and 4-vessel TECAB. TECAB is combined with percutaneous coronary intervention in hybrid procedures. Despite increasing complexity of endoscopic coronary bypass surgery, conversion rates to open bypass surgery have dropped significantly and operative times have decreased. Published major morbidities and mortality rates in arrested-and beating-heart TECAB have been cumulatively in the 0-2% range and are considered well within the expected range for these highly complex surgical procedures. Long-term survival and freedom from major adverse events also meet the standards of open bypass surgery.

Off-pump Bilateral Skeletonized Internal Thoracic Artery Grafting in Elderly Patients

The purpose of the present study was to compare outcome in propensity score-matched patients, aged 70 years or greater, undergoing isolated off-pump coronary bypass surgery using a bilateral (BITA) or single (SITA) skeletonized internal thoracic artery. Of 912 consecutive patients undergoing isolated coronary bypass grafting (906 using the off-pump technique without emergent conversion to cardiopulmonary bypass), the 491 aged 70 years or greater undergoing off-pump skeletonized single (n=247) or bilateral (n=244) skeletonized internal thoracic artery grafting were retrospectively analyzed after excluding the 6 who were transferred to our hospital after receiving percutaneous cardiopulmonary bypass, the 72 who had only 1 target in the left coronary area, and the 343 aged less than 70 years. A total of 217 pairs were matched using propensity scores calculated from 9 preoperative factors (0.69). The rate of postoperative complications was similar between the groups. The 5-year estimated survival free from overall death and cardiac event, respectively, in the BITA group versus the SITA group were 86.4%±3.2% versus 73.5%±3.9% (p=0.01) and 93.2%±2.7% versus 87.5%±3.0% (p=0.01). In multivariate Cox models, bilateral internal thoracic artery grafting was significantly associated with a lower risk of overall death (hazard ratio 0.56; 95% confidence interval 0.31 to 0.99; p=0.04) and cardiac event (hazard ratio 0.36; 95% confidence interval 0.15 to 0.88; p=0.03). In elderly patients, off-pump in situ left-sided bilateral skeletonized internal thoracic artery grafting is associated with lower risk of overall death and cardiac event than single internal thoracic artery grafting and carries no increased operative risk.

The right internal thoracic artery

The left internal thoracic artery is acknowledged as the best coronary conduit. The right internal thoracic artery (RITA) is identical to the left ITA (LITA), yet, despite excellent published results, the RITA [as part of bilateral ITA (BITA) grafting] is rarely used in coronary artery bypass graft surgery (CABG). With advances in CABG and drug-eluting stents (DESs) for coronary artery disease, it is timely to review the clinical and patency results when RITA is used in BITA, to define its role in the treatment of multivessel coronary artery disease. RITA use is 4% in the USA, and 10% in the UK and Australia, although higher in some centres. Perioperative mortality of BITA is 1-3%. Morbidity is low, 1-2% for stroke and perioperative myocardial infarction, and 2-3% for postoperative bleeding. Deep sternal wound infection is also low, 1-3%. Excellent results are reported for RITA/BITA in off-pump coronary artery bypass, in patients with renal dysfunction and those with end-stage renal failure and on dialysis. BITA is well tolerated in routine diabetic patients with multivessel coronary disease and may enhance their long-term prognosis. Patencies for RITA are identical to LITA in comparable territories and superior to non-ITA grafts, resulting in enhanced long-term patient outcomes. As evidence of excellent RITA results increases, strategies are required to encourage its use. Skeletonization, free, and composite grafts, associated with excellent clinical results and patencies, enhance RITA versatility and are important in improving long-term prognosis. The role of BITA/CABG versus DESs also needs further definition.