Incidence and clinical implications of intraoperative BITA grafts conversion. Insights from the Arterial Revascularization Trial

Background: The arterial revascularization trial (ART) has been designed to answer the question whether the use of bilateral internal thoracic arteries (BITA) can improve 10-year outcomes when compared to single internal thoracic artery (SITA). In the ART, a significant proportion of patients initially allocated to BITA received other conduit strategies. We sought to investigate the incidence and clinical implication of BITA grafts conversion in the ART. Methods: Among patients enrolled in the ART (n=3102), we excluded those allocated to SITA (n=1554), those who did not undergo surgery (n=16) and those operated on but withdrew after randomization (n=7). Propensity score matching was used to compare converted vs non-converted BITA groups. Results: A total of 1525 patients were operated with intention to receive BITA grafting. Of those, 233 (15.3%) were converted to other conduit selection strategies. Incidence of conversion largely varied across 28 centres involved (from 0% to 42.9%). The most common reason for BITA grafts conversion was the evidence of at least one internal thoracic artery not suitable which was reported in 77 cases. Patients with intraoperative BITA graft conversion received a lower number of grafts (2.95±0.84 vs 3.21±0.74; P<0.001). However, hospital mortality rate was comparable to those who did not require BITA graft conversion (0 vs 1.6%; P=0.1) as well as the incidence of major complications. At 5 years we found a non-significant excess of deaths (11.9% vs 8.4%; P=0.1) and major adverse events (17.1% 13.2%; P=0.1) mainly driven by an excess of revascularization in patients requiring conversion. Conclusions: The incidence of intraoperative BITA graft conversion is not irrelevant . BITA graft conversion is not associated with increased operative morbidity but its effect on late outcomes remain uncertain

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

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

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 (CABG) surgery remains unclear. The Arterial Revascularization Trial (ART) 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 a RA graft instead of a saphenous vein graft (SVG). We aimed to investigate the associations between using the RA instead of 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 based on conduits actually received (as treated). The analysis included 2737 patients who received a RA graft (RA group, n=632) or SVG only (SVG group, n=2105) in addition to SITA or BITA grafts. The primary endpoint 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 two strategies.  Results—MI, cardiovascular death and repeat revascularization cumulative incidence was 2.3% (95%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 endpoint was significantly lower in the RA group (8.8%; 95%CI 6.5-11.0) when compared with the SVG group (13.6%; 95%CI 10.8-16.3) (P=0.005). This association was present when a 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 mid-term major adverse cardiac events when used to supplement SITA or BITA grafts

One-year costs of bilateral or single internal mammary grafts in the Arterial Revascularisation Trial

Objective: Coronary artery bypass grafting (CABG) using bilateral internal mammary arteries (BIMA) may improve survival over CABG using single internal mammary arteries (SIMA), but may be surgically more complex (and therefore costly) and associated with impaired sternal wound healing. We report, for the first time, a detailed comparison of healthcare resource use and costs over 12 months, as part of the Arterial Revascularisation (ART) Trial.  Methods: 3102 patients in 28 hospitals in seven countries were randomised to CABG surgery using BIMA (n=1548) or SIMA (n=1554). Detailed resource use data were collected covering surgery, the initial hospital episode, and for 12 months post randomisation. Using UK unit costs, total costs were calculated and compared between trial arms and for subgroups.  Results: Patients randomised to BIMA spent 20 min longer in theatre (95% CI 15 to 25, p<0.001) and also required more treatment for sternal wound problems. Mean (SD) total costs per patient at 12 months were £13 839 (£10 534) for BIMA and £12 717 (£9719) for SIMA (mean cost difference £1122, 95% CI £407 to £1838, p=0.002). No tests for interaction between subgroups and treatment allocation were significant.  Conclusions: At 12 months from randomisation, mean costs were approximately 9% higher in BIMA than SIMA patients, primarily due to longer time in theatre and in-hospital stay, and slightly higher costs related to sternal wound problems during follow-up. Follow-up to the primary trial endpoint of 10 years will reveal whether longer-term differences emerge in graft patency or in overall survival

Off-pump versus on-pump coronary artery bypass grafting: Insights from the Arterial Revascularization Trial

Background: The long-term effects of off-pump coronary artery bypass continue to be controversial because some studies have reported increased adverse event rates with off-pump coronary artery bypass when compared with on-pump coronary artery bypass. The Arterial Revascularization Trial compared survival after bilateral versus single internal thoracic artery grafting. The choice of off-pump coronary artery bypass versus on-pump coronary artery bypass was based on the surgeon's discretion. We performed a post hoc analysis of the Arterial Revascularization Trial to compare 5-year outcomes with 2 strategies. Methods: Among 3102 patients enrolled in the Arterial Revascularization Trial, we selected 1260 patients who underwent off-pump coronary artery bypass versus 1700 patients who underwent on-pump coronary artery bypass with cardioplegic arrest for the present comparison. Primary outcomes were 5-year mortality and incidence of major cardiac and cerebrovascular events, including cardiovascular death, myocardial infarction, cerebrovascular accident, and revascularization after index procedure. Propensity score matching selected 1260 pairs for final comparison. Stratified Cox models were used for treatment effect estimate. Results: Hospital mortality was comparable between off-pump coronary artery bypass and on-pump coronary artery bypass groups (12 [1.0%] vs 15 [1.2%]; P = .7). Conversion rate to on-pump during off-pump coronary artery bypass was 29 of 1260 (2.3%). When compared with off-pump coronary artery bypass not converted, off-pump coronary artery bypass converted to on-pump presented a remarkably higher hospital mortality (10.3% vs 0.7%; P < .001). At 5 years, the mortality rate was 110 (8.9%) versus 102 (8.3%) in the off-pump coronary artery bypass and on-pump coronary artery bypass groups, respectively, with no significant difference (hazard ratio, 1.14; 95% confidence interval, 0.86-1.52; P = .35). Incidence of major cardiac and cerebrovascular events was 175 (14.3) versus 169 (13.8) in the off-pump coronary artery bypass and on-pump coronary artery bypass groups, respectively, with no significant difference (hazard ratio, 1.05; 95% confidence interval, 0.84-1.31; P = .65). Conclusions: The present post hoc Arterial Revascularization Trial analysis supports the hypothesis that both off-pump coronary artery bypass and on-pump coronary artery bypass are equally effective and safe

Effect of total arterial grafting in the Arterial Revascularization Trial

Objectives The Arterial Revascularization Trial (ART) was designed to compare 10-year survival in bilateral versus single internal thoracic artery grafts. The intention-to-treat analysis has showed comparable outcomes between the 2 groups but an explanatory analysis suggested that those receiving 2 or more arterial grafts had better survival. Whether the exclusive use of arterial grafts provide further benefit is unclear. Methods We performed an exploratory analysis of the ART based on conduits actually received (as-treated principle). From ART cohort, only patients receiving at least 3 grafts were included. The final population consisted of 1084, 1010, and 390 patients in the single arterial graft (SAG) group, in the multiple arterial graft (MAG) group (2 or more arterial grafts with additional saphenous veins) and total arterial graft (TAG) group (3 or more arterial grafts only) respectively. Inverse probability of treatment weighting was used for comparison. Results When compared with the SAG group, there was a significant trend toward a reduction of 10-year mortality in the MAG and TAG group (test for trend P = .02). The TAG group was associated with the lowest risk of late mortality (hazard ratio, 0.68; 95% confidence interval, 0.48-0.96; P = .03) and with a significant risk reduction of the composite of death/myocardial infarction/stroke and repeat revascularization (hazard ratio, 0.71; 95% confidence interval, 0.53-0.94; P = .02). Conclusions When compared with SAG, both MAG and TAG represent valuable strategies to improve clinical outcomes following coronary artery bypass grafting but TAG can potentially provide further benefit.</p

Off-pump versus on-pump coronary artery bypass grafting. Insights from the Arterial Revascularization Trial

Background The long-term effects of (OPCAB) continue to be controversial as some studies have reported increased adverse event rates with OPCAB when compared to on-pump coronary artery bypass (ONCAB). The Arterial Revascularization Trial (ART) compared survival after bilateral versus single internal thoracic artery grafting. The choice of OPCAB versus ONCAB was based on surgeon’s discretion. We performed a post-hoc analysis of the ART to compare 5-year outcomes with two strategies. Methods Among 3102 patients enrolled in the ART, we selected 1260 patients who underwent OPCAB versus 1700 patients who underwent ONCAB with cardioplegic arrest for the preent comparison. Primary outcomes were 5-year mortality and incidence of major cardiac and cerebrovascular events (MACCE) including cardiovascular death, myocardial infarction, cerebrovascular accident and revascularization after index procedure. Propensity score matching selected 1260 pairs for final comparison. Stratified Cox models were used for treatment effect estimate. Results Hospital mortality was comparable between OPCAB and ONCAB groups (12[1.0%] vs 15[1.2%]; P=0.7). Conversion rate to on pump during OPCAB was 29/1260 (2.3%). When compared to OPCAB not converted, OPCAB converted to on-pump presented a remarkably higher hospital mortality (10.3% vs 0.7%; P&lt;0.001). At 5 years, mortality rate was 110(8.9%) vs. 102(8.3%) in the OPCAB and ONCAB groups respectively with no significant difference (hazard ratio, HR 1.14; 95% confidence interval, CI 0.86-1.52; P=0.35). Incidence of MACCE was 175(14.3) vs. 169 (13.8) in the in the OPCAB and ONCAB groups respectively with no significant difference (HR 1.05; 95%CI 0.84-1.31; P=0.65). Conclusions The present post-hoc ART analysis supports the hypothesis that both OPCAB and ONCAB are equally effective and safe