RESUMEN
OBJECTIVE: Investigate the association between the presence and grafting of chronic total occlusions (CTO) and coronary artery bypass grafting (CABG) outcomes. METHODS: This was a post hoc analysis of the REGROUP trial, which randomized veterans undergoing isolated on-pump CABG to endoscopic versus open vein harvest (2014-2017). Patients were stratified based on the presence of at least one CTO vessel (a 100% occluded coronary lesion for greater than or equal to 3 months), and according to whether all CTO vessels were bypassed. Rates of major cardiac adverse events (MACE) were compared. RESULTS: At least 1 CTO was present in 453/1,149 patients (39.4%). Over a median follow up of 4.7 years (interquartile range 3.84-5.45), MACE rates were 23.4% vs. 22.2% for the CTO vs. no CTO group, respectively (adjusted hazard ratio [AHR] 0.92, 95% CI 0.70-1.20). MACE rates for patients with complete CTO grafting vs. not were 23.1% vs. 25.0%, respectively (AHR 0.95, 95% CI 0.57-1.57) . In patients with right coronary dominance undergoing LAD grafting, bypassing a RCA CTO was associated with significantly lower rates of all-cause mortality (AHR 0.38, 95% CI 0.17-0.83). CONCLUSIONS: In this REGROUP trial subanalysis, neither CTO presence or complete grafting of CTO vessels were associated with significantly different rates of MACE. However, the finding of possible survival benefit among a subgroup of patients undergoing grafting of a dominant RCA CTO vessel alongside LAD grafting warrants additional study.
RESUMEN
There is growing evidence in support of coronary complete revascularization (CR). Nonetheless, there is no universally accepted definition of CR in patients who undergo coronary bypass grafting surgery (CABG). We sought to investigate the outcomes of CR, defined as surgical revascularization of any territory supplied by a suitable coronary artery with ≥50% stenosis. We performed a preplanned subanalysis in the Randomized Trial of Endoscopic or Open Saphenous Vein Graft Harvesting (REGROUP) clinical trial cohort. Of 1,147 patients who underwent CABG, 810 (70.6%) received CR. The primary outcome was a composite of major adverse cardiac events (MACEs), including death from any cause, nonfatal myocardial infarction, or repeat revascularization over a median 4.7 years of follow-up. MACE occurred in 175 patients (21.6%) in the CR group and 86 patients (25.5%) in the incomplete revascularization (IR) group (hazard ratio [HR] 0.87, 95% confidence interval [CI] 0.67 to 1.13, p = 0.29). A total of 97 patients (12.0%) in the CR group and 48 patients (14.2%) in the IR group died (HR 0.93, 95% CI 0.65 to 1.32, p = 0.67); nonfatal myocardial infarction occurred in 49 patients (6.0%) in the CR group and 30 patients (8.9%) in the IR group (HR 0.76, 95% CI 0.48 to 1.2, p = 0.24), and repeat revascularization occurred in 62 patients (7.7%) in the CR group and 39 patients (11.6%) in the IR group (HR 0.64; 95% CI 0.42 to 0.95, p = 0.027). In conclusion, in patients with a great burden of co-morbidities who underwent CABG in the REGROUP trial over a median follow-up period of a median 4.7 years, CR was associated with similar MACE rates but a reduced risk of repeat revascularization. Longer-term follow-up is warranted.