Abstract
Background Revascularization strategy in coronary artery bypass grafting (CABG) surgery usually
depends on coronary dimension and stenosis severity. Little is known about the relation
of preoperative evaluation of scarcely or invisibly chronic occluded coronary arteries
(chronic total occlusion [CTO]) and revascularization rate or anastomosis quality.
We aimed to evaluate the success rates of CTO revascularization in CABG surgery and
determine the influence of coronary lumen visibility and collateralization in preoperative
angiograms on revascularization rates, bypass blood flow, and target vessel diameter.
Method Preoperative coronary angiograms were evaluated for 938 consecutive patients who
underwent isolated CABG surgery between 2014 and 2016 and screened for occluded coronary
arteries. The occluded vessels were scored for visibility using the Rentrop grading
of collateral filling. Intraoperatively, dimensions of the occluded arteries were
measured using conventional vessel probes, and anastomosis quality was assessed by
transit time flow measurement.
Results A total of 404 (43.1%) patients were identified with at least one CTO. Revascularization
rates differed from 96.2% in the left anterior descending artery, to 85.0% in left
circumflex artery-dependent vessels, and 78.8% in right coronary artery territory.
Coronary visibility and grade of collateralization in the preoperative angiogram had
no influence on intraoperatively measured coronary diameter. Bypass blood flow in
grafts revascularizing CTOs lacking collateralization were not significantly lower
than those grafts leading to CTOs with higher Rentrop scores.
Conclusion Preoperative coronary assessment often differs from intraoperative findings. Our
study confirms that even patients with scarcely collateralized CTOs and impaired visibility
in the coronary angiogram have a high chance of complete revascularization during
CABG surgery.
Keywords
chronic total occlusion - CTO - complete revascularization - CABG - surgical revascularization
