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

Clinical and financial outcomes associated with the utilization of right internal mammary artery versus radial artery in multivessel coronary artery bypass grafting

BACKGROUND

Multi-arterial coronary bypass grafting with the left internal mammary artery as a conduit has been shown to offer superior long-term survival compared to single-arterial coronary bypass grafting. Nevertheless, the selection of a secondary conduit between the right internal mammary artery and the radial artery remains controversial. Using a national cohort, we examined the relationships between the right internal mammary artery and the radial artery with acute clinical and financial outcomes.

METHODS

Adults undergoing on-pump multivessel coronary bypass grafting with left internal mammary artery as the first arterial conduit were identified in the 2016 to 2020 Nationwide Readmissions Database. Patients receiving either the right internal mammary artery or the radial artery, but not both, were included in the analysis. Multivariable regression models were fitted to examine the association between the conduits and in-hospital mortality, as well as additional secondary outcomes.

RESULTS

Of an estimated 49,798 patients undergoing multi-arterial coronary bypass grafting, 29,729 (59.7%) comprised the radial artery cohort. During the study period, the proportion of multi-arterial coronary bypass grafting utilizing the radial artery increased from 51.3% to 65.2% (nptrend <0.001). Following adjustment, the radial artery was associated with reduced odds of in-hospital mortality (adjusted odds ratio 0.44), prolonged mechanical ventilation (adjusted odds ratio 0.78), infectious complications (adjusted odds ratio 0.69), and 30-day nonelective readmission (adjusted odds ratio 0.77, all P < .05).

CONCLUSION

Despite no definite endorsement from surgical societies, the radial artery is increasingly utilized as a secondary conduit in multi-arterial coronary bypass grafting. Compared to the right internal mammary artery, the radial artery was associated with lower odds of in-hospital mortality, complications, and reduced healthcare expenditures. These results suggest that whenever feasible, the radial artery should be the favored conduit over the right internal mammary artery. Nevertheless, future studies examining long-term outcomes associated with these vessels remain necessary.

Current indications and surgical strategies for myocardial revascularization in patients with left ventricular dysfunction: a scoping review

BACKGROUND

Ischemic cardiomyopathy (ICM) accounts for more than 60% of congestive heart failure cases and is associated with high morbidity and mortality rates. Myocardial revascularization in patients with left ventricular dysfunction (LVD) and a left ventricular ejection fraction (LVEF) ≤35% aims to improve survival and quality of life and reduce complications associated with heart failure and coronary artery disease. The majority of randomized clinical trials have consistently excluded those patients, resulting in evidence primarily derived from observational studies.

MAIN BODY

We performed a scoping review using the Arksey and O'Malley methodology in five stages: 1) formulating the research question; 2) locating relevant studies; 3) choosing studies; 4) organizing and extracting data; and 5) compiling, summarizing, and presenting the findings. This literature review covers primary studies and systematic reviews focusing on surgical revascularization strategies in adult patients with ischemic left ventricular dysfunction (LVD) and a left ventricular ejection fraction (LVEF) of 35% or lower. Through an extensive search of Medline and the Cochrane Library, a systematic review was conducted to address three questions regarding myocardial revascularization in these patients. These questions outline the current knowledge on this topic, current surgical strategies (off-pump vs. on-pump), and graft options (including hybrid techniques) utilized for revascularization. Three independent reviewers (MAE, DP, and AM) applied the inclusion criteria to all the included studies, obtaining the full texts of the most relevant studies. The reviewers subsequently assessed these articles to make the final decision on their inclusion in the review. Out of the initial 385 references, 156 were chosen for a detailed review. After examining the full articles were examined, 134 were found suitable for scoping review.

CONCLUSION

The literature notes the scarcity of surgical revascularization in LVD patients in randomized studies, with observational data supporting coronary revascularization's benefits. ONCABG is recommended for multivessel disease in LVD with LVEF < 35%, while OPCAB is proposed for older, high-risk patients. Strategies like internal thoracic artery skeletonization harvesting and postoperative glycemic control mitigate risks with BITA in uncontrolled diabetes. Total arterial revascularization maximizes long-term survival, and hybrid revascularization offers advantages like shorter hospital stays and reduced costs for significant LAD lesions.

Effect of right internal mammary artery versus radial artery as a second graft vessel in coronary artery bypass grafting on postoperative wound infection in patients: A meta-analysis

Few studies have shown that radial artery (RA), which is used as a secondary arterial graft, offers superior results compared with right internal thoracic artery (RIMA) in coronary artery bypass grafting (CABG). In a meta-analysis of observational studies starting in 2023, we looked at the effect of re-operation on postoperative infection and haemorrhage in CABG with RA vs. RIMA. The electronic database up to October 2023 was examined in the course of the research. Analysis was carried out on the clinical trials of postoperative wound infections and haemorrhage re-surgery. Among 912 trials associated with CABG, we selected 8 trials to be included in the final data analysis. The main results were secondary wound infection and re-operation after surgery. The odds ratios (OR) and confidence intervals (CIs) were computed on the basis of a randomized or fixed-effect model of wound infection and re-operation. Seven trials showed a significant reduction in the risk of wound infection in RA treated as a secondary artery transplant compared with RIMA (OR, 1.60; 95% CI, 1.03, 2.47 p = 0.04); Four trials showed that RIMA was not significantly different from RA in the rate of re-operation for postoperative bleeding (OR, 1.31; 95% CI, 0.60, 2.88 p = 0.50). In CABG, RA is used as a secondary arterial conduit graft to lower the risk of wound infection in CABG patients.

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

OBJECTIVES

We 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.

METHODS

PubMed, 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.

RESULTS

Twelve 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).

CONCLUSIONS

The 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.

Refinement of Coronary Artery Bypass Grafting at Juntendo University Hospital

Surgical treatment of ischemic heart disease began in 1945. After 1970, coronary artery bypass grafting (CABG) with cardiopulmonary bypass was developed along with coronary angiography. Juntendo University has been treating ischemic heart disease since 1980, and is actively performing off-pump CABG (OPCAB) since 2002. Besides the age of patients undergoing surgery, complications such as chronic hemodialysis, cerebrovascular disease, and malignancies make it challenging to reduce postoperative complications using OPCAB as graft preservation. OPCAB is technically challenging, and the CORONARY trial did not reveal its superiority over conventional CABG. Furthermore, high revascularization rates and technical differences among surgeons are important concerns. While not widely accepted in Europe and the United States, OPCAB comprises 65% of all stand-alone CABG in Japan. Japan reported a 2.5% hospital mortality rate in 2018, while the US reported 2.2% (according to the American Association of Thoracic Surgeons). In contrast, Juntendo University Hospital has maintained a 1% hospital mortality rate since 1984. To reduce the incidence of remote stroke in CABG patients, Juntendo has been using stroke-free management since 2010. Postoperative atrial fibrillation is 4-5 times more likely to recur than normal sinus rhythm after a 5-year course. In our study, 20% of patients suffered from chronic atrial fibrillation after ten years. Furthermore, left atrial appendage closure or amputation significantly reduces stroke in patients who undergo CABG and develop postoperative atrial fibrillation. Thus, OPCAB is a minimally invasive procedure with fewer complications; prevention of cardiogenic cerebral infarction can help improve remote outcomes.

[Revascularización quirúrgica utilizando dos arterias torácicas internas en Sudamérica]

La derivación de la arteria coronaria utilizando la arteria torácica interna bilateral se ha relacionado con beneficios de supervivencia en pacientes con enfermedad arterial coronaria, pero los datos no son concluyentes. En Sudamérica, varios centros reportaron su propia experiencia con buenos resultados en supervivencia, mínimos eventos cardiovasculares postoperatorios y un bajo grado de infección mediastínica, sin embargo, el número de casos es bajo y la ausencia de publicaciones en varios países es preocupante. Revisamos las principales publicaciones sobre el injerto de arteria torácica interna bilateral en nuestra región, evaluando cuánto hemos avanzado en la cirugía coronaria.

Multi-arterial and total-arterial coronary revascularization: Past, present, and future perspective

BACKGROUND AND AIM OF THE STUDY

Although abundant biological, clinical, and scientific evidence exists on the superiority of multi-arterial (MAR) and total-arterial revascularization (TAR) over the conventional strategy with a single internal thoracic artery, only 10% of patients undergoing coronary artery bypass grafting (CABG) in the United States receives a second arterial conduit, and only 5% of patients receives TAR.

METHODS AND RESULTS

In January 2020, the authors performed comprehensive search to identify studies that evaluated MAR and TAR strategies through the MEDLINE database.

CONCLUSIONS

In this paper, the authors reviewed the literature on the historical and current evidence in favor of MAR and TAR, thus underlying why current CABG practice needs qualitative improvement.

Total arterial off-pump coronary revascularization: The Holy Grail?

PURPOSE OF REVIEW

Coronary artery bypass grafting (CABG) remains the standard of care for patients with complex multivessel coronary artery disease. However, conventional CABG utilizing left internal mammary artery and supplemental vein grafts performed on cardiopulmonary bypass is marred by questionable long-term patency of vein grafts and risk of neurological injury. Total arterial off-pump CABG is a strategy associated with avoidance of neurological injury and vein graft failure. The aim of this review is to summarize recent evidence on safety and effectiveness of total arterial off-pump CABG.

RECENT FINDINGS

Two key studies have been published recently. One describes a dual inflow technique that achieves anaortic, off-pump complete revascularization using arterial grafts only. The other is single centre study that reports 10-year survival of 89.33%, rate of freedom from repeat revascularization of 91.33% and early stroke rate of 0.9% after total arterial off-pump CABG.

SUMMARY

Total arterial off-pump CABG with its advantages of improved survival, enhanced freedom from repeat revascularization and low stroke rate can be regarded as the Holy Grail of myocardial revascularization. However, the results of a large, multicenter, prospective trial are required to substantiate this status.

Bilateral internal thoracic artery versus single internal thoracic artery: a meta-analysis of propensity score-matched observational studies

The lack of benefit in terms of mid-term survival and the increase in the risk of sternal wound complications published in a recent randomized controlled trial have raised concerns about the use of bilateral internal thoracic artery (BITA) in myocardial revascularization surgery. For this reason, we decided to explore the current evidence available on the subject by carrying out a meta-analysis of propensity score-matched studies comparing BITA versus single internal thoracic artery (SITA). PubMed, EMBASE and Google Scholar were searched for propensity score-matched studies comparing BITA versus SITA. The generic inverse variance method was used to compute the combined hazard ratio (HR) of long-term mortality. The DerSimonian and Laird method was used to compute the combined risk ratio of 30-day mortality, deep sternal wound infection and reoperation for bleeding. Forty-five BITA versus SITA matched populations were included. Meta-analysis showed a significant benefit in terms of long-term survival in favour of the BITA group [HR 0.78; 95% confidence interval (CI) 0.71-0.86]. These results were consistent with those obtained by a pooled analysis of the matched populations comprising patients with diabetes (HR 0.65; 95% CI 0.43-0.99). When compared with the use of SITA plus radial artery, BITA did not show any significant benefit in terms of long-term survival (HR 0.86; 95% CI 0.69-1.07). No differences between BITA and SITA groups were detected in terms of 30-day mortality or in terms of reoperation for bleeding. Compared with the SITA group, patients in the BITA group had a significantly higher risk of deep sternal wound infection (risk ratio 1.66; 95% CI 1.41-1.95) even when the pooled analysis was limited to matched populations in which BITA was harvested according to the skeletonization technique (risk ratio 1.37; 95% CI 1.04-1.79). The use of BITA provided a long-term survival benefit compared with the use of SITA at the expense of a higher risk of sternal deep wound infection. The long-term survival advantage of BITA is undetectable when compared with SITA plus radial artery.

Off-pump Revascularization with Bilateral versus Single Mammary Arteries-A Propensity Score-Matched Analysis

BACKGROUND

Coronary artery bypass grafting is the first-line therapy for severe multivessel coronary artery disease. We aimed to investigate the clinical outcome in patients undergoing isolated off-pump surgery with the single or bilateral internal mammary artery (SIMA or BIMA) approach.

METHODS

We performed a propensity score-matched analysis in 1,852 consecutive patients, aged 50 to 70 years, who underwent myocardial revascularization at our institution between July 2009 and August 2016. Primary end point was the probability of survival.

RESULTS

Mean follow-up was 36.3 (range: 0.1-89.6) months. The probability of survival in the SIMA and BIMA groups was 98.6 and 99.0% at year 1, 92.0 and 92.5% at year 5, and 85.6 and 81.6% at year 7, respectively, with a hazard ratio (HR) of mortality for the BIMA group versus the SIMA group of 0.98 (95% confidence interval[CI]: 0.64-1.52; p = 0.94). There was evidence for interaction between diabetes and study group on mortality risk (HR = 2.59, 95% CI: 1.07-6.23; p = 0.034). Freedom from mediastinitis/wound infection was higher in the SIMA group than in the BIMA group (99.5 and 96.9%, respectively; HR of an event = 6.39, 95% CI: 2.88-14.18; p < 0.001). The corresponding values in the subgroups of diabetic patients were 98.6 and 90.9%, respectively (HR = 6.45, 95% CI: 2.24-18.58; p = 0.001). Mediastinitis/wound infection was associated with increased mortality risk (HR = 2.96, 95% CI: 1.29-6.78; p = 0.010).

CONCLUSION

Overall, our data indicate similar probability of survival up to a maximum follow-up of 7 years by off-pump surgery with the SIMA or BIMA approach. However, in diabetic patients, the clinical outcome indicates caution regarding the use of the BIMA approach.

The radial artery in coronary surgery, 2018

It is now 25 years since the radial artery (RA) was reintroduced in coronary surgery. It has evolved into being a significant coronary artery bypass conduit and ranks third in usage after the internal thoracic artery (ITA) and saphenous vein grafts (SVG). Its advantages are that it can be readily and efficiently harvested, is of good length and appropriate size for coronary artery bypass graft (CABG) surgery, is robust and easy to handle, and remains free of atheroma, and there is minimal wound morbidity. The RA must be used judiciously with attention to spasm prophylaxis because of its muscular wall, and by avoiding competitive flow. Its patency is equivalent to the ITAs when placed to similar coronary territories and under similar conditions (stenosis, size, quality) and RA patencies are always superior to those of SVG in both observational and randomized studies-88-90% versus 50-60% at 10 years, and 80-87% versus 25-40% at 20 years. Its use and excellent patencies result in survival results equivalent to bilateral internal thoracic artery (BITA) grafting and always superior to left internal thoracic artery (LITA) +SVG. Typical radial artery multiarterial bypass grafting (RA-MABG) 10-year survivals are 80-90% versus 70-80% for LITA-SVG. In general, for every 100 patients undergoing CABG, 10 more patients will be alive at 10 years post-operatively. The RA also is important in achieving total arterial revascularization, and several reports indicate a further survival advantage for patients having three arterial grafts over two. The RAs are especially useful in diabetic, morbidly obese patients, those with conduit shortage, and leg pathology, and in coronary reoperations. Although the RA has equivalent patencies to the right internal thoracic artery (RITA), it is much more versatile. RAs that have been instrumented by angiography or percutaneous coronary intervention should be avoided. The radial artery has proved to be an excellent arterial conduit, is equivalent to but more versatile than the RITA, and is always superior to SVG. Its use should be part of every coronary surgeon's skill set.

Long term outcomes of radial artery grafting in patients undergoing coronary artery bypass surgery

Single arterial left internal thoracic artery (LITA) based coronary artery bypass surgery (LITA-SABG) has been the principal revascularization strategy for over 25 years across all patient demographics. In line with the current emphasis being placed on personalized medicine, which tailors individual, patient-specific therapy to optimize outcomes, coronary artery bypass grafting (CABG) techniques have also evolved to achieve enhanced results among specific groups of patients with coronary artery disease. Most notable has been the development of multi-arterial bypass grafting (MABG) techniques, using either the radial artery (RA) or the right internal thoracic artery (RITA) in conjunction with the LITA, as both techniques have been shown to enhance long term survival of CABG patients. This article reviews the latest data on the long-term outcomes of RA-MABG and considers its impact in various sub-cohorts of CABG that are increasingly being treated by cardiac surgeons. The primary aim of this review is to highlight the advantages of RA-MABG over LITA-SABG and thereby potentiate its adoption into clinical practice. Our secondary aim is to summarize the results of RA-MABG in specific CABG sub-cohorts, to more closely align CABG surgery with the emerging consensus that personalized medicine enhances healthcare value.

Coronary Artery Bypass Grafting with Arterial Conduits in the Elderly

Although improved long-term outcomes obtained with the use of arterial grafts for coronary revascularization in comparison with the traditional association of a single arterial and saphenous vein grafts have been demonstrated in the overall population, the efficacy of this newer technique in the elderly is difficult to prove because their shorter life expectancy due to advanced heart disease, associated with severe comorbidities. Moreover, more widespread use of this technique is limited by the concerns on the potential morbidity, particularly the longer time required to perform the operation and the possibility of deep sternal wound infection in case of bilateral internal thoracic artery harvesting due to the decreased blood supply to the sternum and surrounding tissues.The review of the recent literature indicates that the use of bilateral internal thoracic arteries in very elderly patients should not be considered routinely. It seems reasonable to avoid it in octogenarians in the presence of well-known predictors of sternal complications such as diabetes, morbid obesity, and severe chronic lung disease.There is also still controversy about the superiority of the radial artery over the saphenous vein graft as a second or third conduit for surgical myocardial revascularization, although the majority of recent studies seem to support more liberal use of the radial artery as second arterial conduit in the elderly. Although a clinical benefit of arterial graft revascularization cannot be formally excluded for elderly patients, the increased complexity of this technique suggests that careful clinical judgment is necessary to select grafts for individual patients.

Contemporary use of arterial and venous conduits in coronary artery bypass grafting: anatomical, functional and clinical aspects

Although the benefits of using the left internal mammary artery to bypass the left anterior descending artery (LAD) have been extensively ascertained, freedom from major cardiovascular events and survival after coronary artery bypass grafting (CABG) also correlate with the completeness of revascularisation. Hence, careful selection of the second-best graft conduit is crucial for CABG success. The more widespread use of saphenous vein grafts contrasts with the well-known long-term efficacy of multiple arterial grafting, which struggles to emerge as the procedure of choice due to concerns over increased technical difficulties and higher risk of postoperative complications. Conduit choice is at the discretion of the operator instead of being discussed by the heart team, where cardiologists are not usually engaged in such decisions due to a hypothetical lack of technical knowledge. Furthermore, according to the ESC/EACTS guidelines, traditional CABG remains the gold standard for multi-vessel coronary artery disease with complex LAD stenosis, but hybrid procedures using percutaneous coronary intervention for non-LAD targets could combine the best of two worlds. With the aim of raising the cardiologist's awareness of the surgical treatment options, we provide a comprehensive overview of the anatomical, functional and clinical aspects guiding the decision-making process in CABG strategy.

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

BACKGROUND

There is controversy about the risk of mediastinitis associated with the use of both internal thoracic arteries (ITA).

METHODS

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).

RESULTS

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).

CONCLUSIONS

In this series of patients, BITA did not increase the risk of mediastinitis in the total population or in the propensity score matched subgroups.

Right internal thoracic artery or radial artery? A propensity-matched comparison on the second-best arterial conduit

OBJECTIVES

We conducted propensity score matching to determine whether the use of the right internal thoracic artery (RITA) confers a survival advantage when compared with the radial artery (RA) as second arterial conduit in coronary artery bypass grafting.

METHODS

The study population included a highly selected low-risk group of patients who received the RITA (n = 764) or the RA (n = 1990) as second arterial conduit. We obtained 764 matched pairs that were comparable for all pretreatment variables. A time-segmented Cox regression model that stratified on the matched pairs was used to investigate the effect of treatment on late mortality.

RESULTS

After a mean follow-up of 10.2 ± 4.5 years (maximum 17.3 years), survival probabilities at 5, 10, and 15 years were 96.4% ± 0.7% versus 95.4% ± 0.7%, 91.0% ± 1.1% versus 89.1% ± 1.2%, and 82.4% ± 1.9% versus 77.2% ± 2.5% in the RITA and RA groups, respectively. During the first 4 years, RITA and RA were comparable in terms of mortality (hazard ratio [HR], 1.00; 95% confidence interval [CI], 0.56-1.78; P = .98). However, after 4 years RITA was associated with a significant reduction in late mortality (HR, 0.67; 95% CI, 0.48-0.95; P = .02). RITA was superior to RA when the experimental conduit was used to graft the left coronary system (HR, 0.69; 95% CI, 0.47-0.99; P = .04) but not the right coronary system (HR, 0.98; 95% CI, 0.59-1.62; P = .93).

CONCLUSIONS

In a highly selected low-risk group of patients, the use of the RITA as second arterial conduit instead of the RA was associated with better survival when used to graft the left but not the right coronary artery.

Is the Risk of Wound Infection Related to Bilateral Internal Thoracic Artery Graft Potentiated by Age?

BACKGROUND

Older age and the use of bilateral internal thoracic artery (ITA) grafting are both considered risk factors for surgical wound infection (SWI) after coronary artery bypass grafting (CABG). The 2014 European Guidelines recommend that bilateral ITA grafting should be considered in patients aged younger than 70 years. Our aim was to investigate interaction between age and the number of ITA grafts.

METHODS

All patients aged 18 years and older who had undergone CABG with at least 1 ITA at Rouen University Hospital between 2001 and 2012 were selected. Data regarding surgical procedure (single/bilateral ITA grafting) were extracted from the medical information system. SWI was identified from prospective surveillance of patients according to Centers for Disease Control and Prevention criteria. Independent factors associated with SWI were assessed by logistic regression, and an interaction test between age (≤69 or ≥70 years) and the number of ITA grafts was performed.

RESULTS

SWI occurred in 71 of 2,726 patients (2.6%). Bilateral ITA grafting was associated with SWI (adjusted odds ratio [aOR], 2.55; 95% confidence interval, 1.51 to 4.30). After fitting an interaction term between age and number of ITA grafts, the aORs for SWI after bilateral ITA grafting substantially differed between patients aged 69 years and younger (aOR, 1.88; 95% confidence interval, 0.94 to 3.75) and 70 years and older (aOR, 3.52; 95% confidence interval, 1.69 to 7.33). However, this interaction failed to reach statistical significance (p = 0.2213), possibly because of insufficient statistical power (23.5%) despite the large sample size.

CONCLUSIONS

Age 70 years and older compared with age 69 years and younger was associated with higher occurrence of SWI after bilateral ITA grafting, but this interaction was not statistically significant. Larger studies are needed to test this interaction.

Right internal thoracic artery versus radial artery as the second best arterial conduit: Insights from a meta-analysis of propensity-matched data on long-term survival

OBJECTIVE(S)

We conducted a meta-analysis of propensity score-matching (PSM) studies comparing long-term survival of patients receiving right internal thoracic artery (RITA) versus radial artery (RA) as a second arterial conduit for coronary artery bypass grafting.

METHODS

A literature search was conducted using MEDLINE, EMBASE, and Web of Science to identify relevant articles. Primary endpoint was long-term mortality. Secondary endpoints were operative mortality, incidence of sternal wound infection, and repeat revascularization. Binary events were pooled using the DerSimonian and Laird method. For time-to-event outcomes, estimates of log hazard ratio (HR) and standard errors obtained were combined using the generic inverse-variance method.

RESULTS

A total of 8 PSM studies were finally selected including 15,374 patients (RITA, 6739; RA, 8635) with 2992 matched pairs for final comparison. Mean follow-up time ranged from 45 to 168 months. When compared with RA, RITA was associated with a lower risk reduction of late death (HR, 0.75; 95% confidence interval [CI], 0.58-0.97; P = .028) and repeat revascularization (HR, 0.37; 95% CI, 0.16-0.85; P = .03). On the other hand, RITA did not increase operative mortality (odds ratio [OR], 1.53; 95% CI, 0.97-2.39; P = .07). RITA was associated with an increased risk of sternal wound complication when pedicled harvesting was used (OR, 3.18; 95% CI, 1.34-7.57), but not with skeletonized harvesting (OR, 1.07; 95% CI, 0.67-1.71).

CONCLUSIONS

The present PSM data meta-analysis suggests that the use of RITA compared with RA was associated with superior long-term survival and freedom from repeat revascularization, with similar operative mortality and incidence of sternal wound complication when the skeletonized harvesting technique was used.

Myocardial Revascularization Exclusively With Bilateral Internal Thoracic Arteries in T-Graft Configuration: Effects on Late Survival

BACKGROUND

We studied long-term survival using bilateral internal thoracic artery (BITA) grafting in a T-configuration exclusively versus using single internal thoracic artery (SITA) grafting in patients with multivessel disease.

METHODS

Consecutive coronary operations performed at a single center between 1996 and 2014 were reviewed. Long-term survival among patients receiving coronary revascularization exclusively with BITA grafting in a T-configuration (n = 2,098) versus SITA grafts plus other types of conduits (saphenous vein graft [SVG] and radial artery [RA]) grafts (n = 1,659). In patients who underwent BITA grafting, the left internal thoracic artery (LITA) was grafted mainly to the left anterior descending artery, whereas the right internal thoracic artery (RITA) was used more commonly to graft the circumflex (Cx) artery and the right coronary system as T-grafts. A total of 485 pairs of patients were matched using propensity scores. Cox proportional hazard models were generated to examine the association of arterial BITA grafting with mortality.

RESULTS

Patients in the BITA group were more likely to be younger (BITA, 63.7 ± 9.1 versus SITA, 65.0 ± 9.9; p < 0.0001). At 30 days, patients who underwent BITA grafting experienced reduced unadjusted mortality (BITA, 1.2% versus SITA, 4.4%; p < 0.0001). At 10 years, patients who underwent BITA grafting experienced superior unadjusted survival (BITA, 82.6% ± 1.8% versus SITA, 76.1% ± 1.3%; p = 0.001). Cox regression analysis in the entire study cohort showed that BITA grafting was associated with improved survival (hazard ratio [HR], 0.71; 95% confidence interval [CI], 0.58-0.87; p < 0.001). In the propensity-score-adjusted analysis, patients who underwent BITA grafting had similar in-hospital mortality (BITA, 1.6% versus SITA, 2.9%; p = 0.196). Patients who underwent BITA grafting still showed improved survival at 10 years (BITA, 81.0% ± 4.1% versus SITA, 71.8% ± 2.5%; p = 0.039).

CONCLUSIONS

This study suggests that coronary artery operations exclusively with BITA grafting in a T-configuration may be associated with better long-term survival than grafting with SITA plus other types of conduits.

Long-term outcome of revascularization with composite T-grafts: Is bilateral mammary grafting better than single mammary and radial artery grafting?

OBJECTIVE

Bilateral internal mammary artery (BIMA) grafting is associated with improved survival. However, many surgeons are reluctant to use this technique, owing to the potentially increased risk of sternal infection. The composite T-graft with radial artery (RA) attached end-to-side to the left internal mammary artery (IMA) provides complete arterial revascularization without increased risk of sternal infection. The purpose of this study is to compare outcomes of these 2 strategies.

METHODS

Patients who underwent BIMA grafting using the composite T-graft technique, between 1996 and 2010 (n = 1329), were compared with 389 patients who underwent composite grafting with a single IMA + RA during the same time period.

RESULTS

Patients undergoing single IMA grafting were older, more often women, and more likely to have diabetes, peripheral vascular disease, and COPD, and to need an emergency operation. Congestive heart failure, left main disease, and recent myocardial infarction were more prevalent with bilateral grafting. Propensity-score matching was used to account for differences between groups in preoperative patient characteristics. The 268 matched pairs had similar characteristics. The median follow-up time was 14.19 (95% confidence interval 13.43-14.95) years. Operative mortality and Kaplan-Meier 10-year survival of the 2 matched groups were similar (3.4% vs 3.7%, and 61.6% vs 64%, for the groups treated with BIMA and single IMA, respectively). Cox-adjusted survival was similar (P = .514). Age, chronic renal failure, and performance of <3 bypass grafts were independent predictors of decreased survival.

CONCLUSIONS

This study suggests that long-term outcomes of arterial revascularization with a composite T-graft constructed using left IMA and RA are not inferior to outcomes after BIMA grafting.

The Society of Thoracic Surgeons Clinical Practice Guidelines on Arterial Conduits for Coronary Artery Bypass Grafting

Internal thoracic arteries (ITAs) should be used to bypass the left anterior descending (LAD) artery when bypass of the LAD is indicated (class of recommendation [COR] I, level of evidence [LOE] B). As an adjunct to left internal thoracic artery (LITA), a second arterial graft (right ITA or radial artery [RA]) should be considered in appropriate patients (COR IIa, LOE B). Use of bilateral ITAs (BITAs) should be considered in patients who do not have an excessive risk of sternal complications (COR IIa, LOE B). To reduce the risk of sternal infection with BITA, skeletonized grafts should be considered (COR IIa, LOE B), smoking cessation is recommended (COR I, LOE C), glycemic control should be considered (COR IIa, LOE B), and enhanced sternal stabilization may be considered (COR IIb, LOE C). As an adjunct to LITA to LAD (or in patients with inadequate LITA grafts), use of a RA graft is reasonable when grafting coronary targets with severe stenoses (COR IIa, LOE: B). When RA grafts are used, it is reasonable to use pharmacologic agents to reduce acute intraoperative and perioperative spasm (COR IIa, LOE C). The right gastroepiploic artery may be considered in patients with poor conduit options or as an adjunct to more complete arterial revascularization (COR IIb, LOE B). Use of arterial grafts (specific targets, number, and type) should be a part of the discussion of the heart team in determining the optimal approach for each patient (COR I, LOE C).

Are all forms of total arterial revascularization equal? A comparison of single versus bilateral internal thoracic artery grafting strategies

OBJECTIVE

Total arterial revascularization (TAR) with internal thoracic arteries (ITAs) and radial arteries (RA) is associated with greater long-term survival compared with the use of a single internal thoracic artery supplemented by veins. The optimal conduit choice and configuration in achieving TAR remains controversial, with uncertainty regarding the individual prognostic impact of ITAs and RAs. As such, among patients solely undergoing TAR, we compared long-term survival between patients receiving single thoracic arteries and those receiving bilateral ITAs.

METHODS

From 1995 to 2010, 2821 patients with 3-vessel coronary artery disease at 8 centers underwent primary isolated coronary artery bypass with TAR using ITAs and RAs. Bilateral ITAs were used in 912 patients. In 380 cases, bilateral in situ ITAs were grafted to the left coronary system. RAs were used in 848 patients (93%) receiving bilateral ITAs and 1906 patients (99.8%) receiving single ITAs. Survival data were obtained using the National Death Index. Separate 1:1 propensity score-matched analyses were performed for (1) bilateral ITA versus single ITA and (2) bilateral ITA incorporating a free right ITA versus single ITA and RAs. Among the 912 patients with bilateral ITAs, those receiving an in situ right ITA to the left coronary system were compared with those receiving a free right ITA.

RESULTS

In the propensity score-matched analysis comparing bilateral versus single ITAs (591 matched pairs), there were similar rates of 30-day mortality and deep sternal wound infection. Bilateral ITA use was associated with greater 15-year survival (79% ± 3.9% vs 67% ± 4.7%, P < .001). In the analysis between bilateral ITA incorporating a free right ITA versus single ITA + RAs (380 matched pairs), bilateral ITA use demonstrated comparable survival at 15 years (79% ± 4.7% vs 67% ± 5.7%, P = .09). Among patients receiving bilateral ITAs, comparison between in situ right ITA versus free right ITA recipients (206 matched pairs) revealed comparable 15-year survival (84% ± 6.1% vs 79% ± 6.7%, P = .13). Multivariable Cox regression found bilateral ITA use to be protective from mortality (hazard ratio, 0.73; 95% confidence interval, 0.59-0.90, P = .004).

CONCLUSIONS

The use of bilateral ITAs as an in situ or free conduit is associated with greater survival and seems to offer a prognostic advantage over the use of only a single ITA supplemented by RAs. Therefore, all configurations of TAR are not equivalent.

Bilateral Internal Thoracic Artery Grafting: Is It Reasonable in Octogenarians?

PURPOSE

The feasibility of using bilateral internal thoracic artery (BITA) grafts for coronary artery bypass grafting (CABG) in octogenarians is not clear. This study aimed to compare outcomes between use of BITA and single internal thoracic artery (SITA) grafts in octogenarians undergoing isolated CABG.

METHODS

Isolated CABG was performed in 1,566 patients at the Sakakibara Heart Institute between September 2004 and December 2012. Of these, 125 consecutive octogenarians were included and divided into two groups, according to the use of BITA grafts (101 subjects) or SITA grafts (24 subjects). Early and late outcomes were compared between groups.

RESULTS

The preoperative patient characteristics were similar between the two groups. Early outcomes were similar, including hospital death or deep sternal infection. The estimated 5-year survival rate was similar in the BITA and SITA groups (78% vs 62%, p = 0.269). Freedom from major adverse cardiac or cerebrovascular events was significantly higher in the BITA group than in the SITA group after 5 years (90% vs 75%, p = 0.032).

CONCLUSIONS

Our results suggest that use of BITA grafts for CABG is feasible and beneficial in octogenarians, resulting in improved late outcomes without increased operative risk.

The radial artery: a forgotten conduit

We reviewed the published literature on the clinical and angiographic outcome of radial artery (RA) grafts and on the comparison between the RA and the other conduits used in coronary operations. The RA is a better graft than the saphenous vein and comparable to the right internal thoracic artery (RITA); moreover, the RA seems a better choice than the RITA in patients at risk of sternal or pulmonary complications. We conclude that the RA should be preferred to the saphenous vein and considered at least equivalent to the RITA as the second conduit during every elective coronary artery bypass procedure.

Bilateral internal mammary artery grafting: rationale and evidence

Coronary artery bypass graft (CABG) surgery remains the preferred mode of revascularization in patients with complex multi-vessel coronary artery disease. The left internal mammary artery (IMA) and saphenous vein are the most commonly utilized conduits in CABG surgery and are still considered to be the gold standard by most surgeons. However, there is emerging evidence that use of bilateral IMAs is associated with significantly better long-term outcomes and the benefit increases with time from surgery. In spite of this incremental beneficiary effect, most surgeons are reluctant to use both IMAs, because it is technically more demanding, time-consuming and is associated with marginally higher sternal wound infection rates. This review highlights the histological features, physiological characteristics and genomics of IMAs that provide the basis for the use of these vessels during CABG surgery. Additionally, the superiority of the bilateral IMAs with regard to patency and long-term outcomes is also discussed in detail. Furthermore, the safety of using bilateral IMAs with regard to early postoperative outcomes with special reference to deep sternal wound infections has been addressed. The present review provides enough evidence to convince more surgeons about the advantages of bilateral IMA grafting.

Off-pump coronary surgery: current justifications

Although the literature has failed to project an overall superiority of off-pump vs. on-pump surgery, nevertheless, small randomized control trials and large meta-analysis studies have concluded that the incidence of a stroke is less than 1 % when anaortic off-pump techniques are advocated in patients with diseased ascending aorta. Furthermore, off-pump techniques or their combination with hybrid procedures may lead to a reduction of adverse outcome in the aged high-risk population with concomitant poor left ventricular function and co-morbidities. However, despite this, controversy still exists among the cardiac surgery community in terms of the benefit of this technique and its safety; hence, off-pump is becoming out of fashion. In this review paper, by looking at a "marginal group of patients" (elderly, high risks, atherosclerotic aortas) we attempt to re-establish and justify this technique and re-invent its usage.

Right internal mammary artery versus radial artery as second arterial conduit in coronary artery bypass grafting: a case-control study of 1526 patients

OBJECTIVE

Additional arterial grafts such as the right internal mammary artery (RIMA) or the radial artery (RA) have been proposed to improve long term outcomes in coronary artery bypass grafting (CABG). RA is largely preferred over RIMA as it is less technically demanding and there is a perception that bilateral IMA usage increases the risk of sternal wound complications. However, there is a paucity of direct comparison of the two conduits to guide surgeons to choose the best second arterial conduit for CABG.

METHODS

A propensity score adjusted analysis of patients undergoing multiple arterial grafting with RIMA (n = 747) and RA (n = 779) during the study period (2001-2013) was conducted to investigate the impact of the two strategies on early and late outcomes.

RESULTS

RIMA did not increase the incidence of postoperative complications including deep sternal wound infection (P = 0.8). Compared to the RIMA, the RA was associated with an increased risk for late mortality (Hazard Ratio [HR] 1.9; 95% confidence interval (CI) 1.2-3.1; P = 0.008) and repeat revascularization (HR 1.5; 95% CI 1.0-2.2; P = 0.044). A trend towards an extra risk for late mortality from RA over RIMA was observed among diabetic (HR 3.3; 95% CI 1.1-9.7) and obese patients (HR 2.1; 95% CI 0.8-5.46).

CONCLUSIONS

RIMA as a second conduit did not increase the operative risk including sternal wound complications and improved long term outcomes including overall survival when compared to RA. This advantage was stronger among diabetic and obese patients. These findings strongly support RIMA as the first choice second arterial conduit in CABG. Further randomized studies with angiographic control and long-term follow-up are needed to address this issue.

Full myocardial revascularization with bilateral internal mammary artery Y grafts

BACKGROUND

Bilateral internal mammary artery (BIMA) grafting in coronary artery surgery provides better long term outcomes than single internal mammary artery and saphenous vein grafting but the optimum configuration of BIMAs has not been established. This study analyzed perioperative and late outcomes of patients who underwent BIMA grafting with a composite Y configuration.

METHODS

Patients (n=922) who underwent BIMA Y grafting were identified from a cardiac surgical database and then cross matched against hospital and cardiology databases and the state death register to identify episodes of repeat coronary angiography, cardiac surgical re-intervention and death. Analysis of repeat angiography was performed after retrieval of the angiogram reports.

RESULTS

In 95% of patients, full myocardial revascularization was achieved with BIMAs alone, using a composite Y configuration with an average of 4.1 IMA to coronary artery anastomoses per patient. The perioperative mortality was 1.5% and the 5-, 10- and 15-year survival estimates were 95%, 87% and 77% respectively. Analysis of 166 symptom-driven post-discharge coronary angiograms showed grafts to the left anterior descending artery and increasing severity of coronary artery stenosis at preoperative angiography as predictors of anastomotic patency.

CONCLUSIONS

Full myocardial revascularization can be achieved with reasonable safety in most patients with triple vessel disease and good left ventricular function, and provides good late survival.

How I choose conduits and configure grafts for my patients-rationales and practices

Coronary artery bypass grafting (CABG) continues to be an effective therapy for many patients with lasting long-term durability and consistent outcomes, despite the development of percutaneous revascularization. The long-term outcome for surgical revascularization depends on multiple variables, including the choice of conduits. However, the choice of coronary conduits has been studied and debated for decades now. In this review article, we examined the current evidences and described our choice on coronary conduits and grafting strategies at our medical center.