Total Arterial Revascularization with Radial Artery and Internal Thoracic Artery T-Grafts Is Associated with Superior Long-Term Survival in Patients Undergoing Coronary Artery Bypass Grafting

AIMS

Compelling evidence encourages the use of the radial artery (RA) as the second arterial graft in coronary artery bypass grafting (CABG). However, its long-term benefits remain disputed. We sought to evaluate long-term outcome and survival by comparing patients receiving RAs with those receiving venous grafts to a single internal thoracic artery (ITA).

METHODS

We analyzed 345 patients undergoing primary multivessel CABG and conducted a 13-year long follow-up. In all, 187 patients received the RA and the left ITA as T-graft; 158 patients received saphenous veins complementing a single ITA. We performed propensity-score matching on 81 pairs to balance treatment selection and confounders.

RESULTS

Patients receiving RAs were younger and less likely to be female or to have pulmonary hypertension, impaired renal function, or left main coronary disease.At 30 days, they showed significantly lower unadjusted mortality and renal impairment. Unadjusted long-term survival was superior in the RA group, even after propensity-score matching. We found that RA use protected from late mortality.

CONCLUSIONS

Using the RA and the left ITA as T-graft is associated with a significant long-term survival benefit in patients undergoing CABG. It may display a promising alternative to conventional use of a single ITA supplemented by saphenous veins.

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

BACKGROUND

Whether the use of the radial artery (RA) can improve clinical outcomes in coronary artery bypass graft surgery remains unclear. The ART (Arterial Revascularization Trial) was designed to compare survival after bilateral internal thoracic artery (BITA) over single left internal thoracic artery (SITA). In the ART, a large proportion of patients (≈20%) also received an RA graft instead of a saphenous vein graft (SVG). We aimed to investigate the associations between using the RA instead of an SVG to supplement SITA or BITA grafts and outcomes by performing a post hoc analysis of the ART.

METHODS

Patients enrolled in the ART (n=3102) were classified on the basis of conduits actually received (as treated). The analysis included 2737 patients who received an RA graft (RA group; n=632) or SVG only (SVG group; n=2105) in addition to SITA or BITA grafts. The primary end point was the composite of myocardial infarction, cardiovascular death, and repeat revascularization at 5 years. Propensity score matching and stratified Cox regression were used to compare the 2 strategies.

RESULTS

Myocardial infarction, cardiovascular death, and repeat revascularization cumulative incidence was 2.3% (95% confidence interval [CI], 1.1-3.4), 3.5% (95% CI, 2.1-5.0), and 4.4% (95% CI, 2.8-6.0) in the RA group and 3.4% (95% CI, 2.0-4.8), 4.0% (95% CI, 2.5-5.6), and 7.6% (95% CI, 5.5-9.7) in the SVG group, respectively. The composite end point was significantly lower in the RA group (8.8%; 95% CI, 6.5-11.0) compared with the SVG group (13.6%; 95% CI, 10.8-16.3; P=0.005). This association was present when an RA graft was used to supplement both SITA and BITA grafts (interaction P=0.62).

CONCLUSIONS

This post hoc ART analysis showed that an additional RA was associated with lower risk for midterm major adverse cardiac events when used to supplement SITA or BITA grafts.

CLINICAL TRIAL REGISTRATION

URL: https://www.situ.ox.ac.uk/surgical-trials/art. Unique identifier: ISRCTN46552265.

The Choice of Conduits in Coronary Artery Bypass Surgery

Coronary artery bypass grafting is the most common cardiac surgery operation performed worldwide. It is the most effective revascularization method for several categories of patients affected by coronary artery disease. Although coronary artery bypass grafting has been performed for more than 40 years, no detailed guidelines on the choice of coronary artery bypass grafting conduits have been published and the choice of the revascularization strategy remains more a matter of art than of science. Moreover, there is a clear contradiction between the proven benefits of arterial grafting and its very limited use in everyday clinical practice. In the hope of encouraging wider diffusion of arterial revascularization and to provide a guide for clinicians, we discuss current evidence for the use of different conduits in coronary artery bypass surgery and propose an evidence-based algorithm for the choice of the second conduit during coronary artery bypass operations.

Is the radial artery associated with improved survival in older patients undergoing coronary artery bypass grafting? An analysis of a multicentre experience†

OBJECTIVES

Studies suggest that the radial artery (RA) may exhibit superior patency compared with the saphenous vein (SV). It is unclear whether older patients undergoing coronary artery bypass grafting (CABG) derive any survival benefit from the use of RAs. We sought to evaluate this using a multicentre database.

METHODS

From 1995 to 2010, 6059 patients with three-vessel coronary artery disease underwent primary isolated CABG at 8 centres. A study cohort of 4006 patients was formed with 3220 (80%) receiving at least 1 RA to supplement a single in situ internal thoracic artery (RA group) while 786 (20%) received only veins to supplement a single ITA (SV group). In the RA group, bilateral RAs were used in 1418 (44%) cases, while total arterial revascularization was achieved in 1859 (58%). RAs were mostly grafted to the left circumflex and right coronary territories. Survival data were obtained using the National Death Index and propensity-score matching was used for risk adjustment. Separate propensity-score analyses were conducted for the 2149 patients (1645 RA, 504 SV) who were 70 years or older.

RESULTS

Patients receiving RAs were younger (mean age in years RA: 68 ± 9.7 vs SV: 71 ± 7.9, P < 0.001) and less likely to have cerebrovascular disease, obstructive airways disease, myocardial infarction within 7 days and left-main coronary disease. At 30 days, RA patients experienced reduced unadjusted mortality (49 of 3220, 1.5% vs 25 of 786, 3.2%, P = 0.004). At 15 years, the RA group showed superior unadjusted survival (51 ± 1.1 vs 35 ± 1.9%, P < 0.001). After propensity-score matching of 507 patient pairs, there was comparable 30-day mortality between groups (RA: 9, 1.8 vs SV: 14, 2.8%, P = 0.41). However, at 15 years, the RA group still showed superior survival (42 ± 2.6 vs 35 ± 2.5%, P = 0.008). Among those 70 years and older (327 matched pairs), despite similar 30-day mortality (RA: 6, 1.8% vs SV: 10, 3.1%, P = 0.42), RA patients again exhibited improved survival (35 ± 3.3 vs 22 ± 2.8%, P = 0.004) at 15 years.

CONCLUSIONS

This multicentre analysis suggests that the use of an RA is associated with a survival benefit in older patients undergoing CABG.