The Role of Computed Tomographic Angiography in Predicting Left Anterior Descending Artery Graftability When Catheter Angiography is Inconclusive
Graftability of the left anterior descending artery (LAD) has important prognostic value for coronary artery bypass graft (CABG) surgery. However, with a chronic total occlusion (CTO) of the LAD, invasive coronary angiography (ICA) may be insufficient to determine its graftability. We evaluated the role of coronary computed tomographic angiography (CTA) in the assessment of CTO and LAD graftability when the distal vessel segment was incompletely visualized by ICA.Materials and Methods:
We enrolled 31 patients with equivocal eligibility for CABG due to CTO of the LAD with poor distal flow defined by ICA. Patients with LAD diameters ≥1.5 mm by CTA underwent CABG surgery, and the vessel diameter was reassessed intraoperatively.Results:
The mean age was 54±14 years. Seven patients (23%) had suitable LAD targets on CTA and underwent successful CABG. Another 24 patients (77%) had nongraftable LADs. Patients with a graftable LAD showed no significant difference between mean LAD diameter measured by CTA and during surgery (1.6±0.3 vs. 1.5±0.3 mm, P=0.21). The preoperative left ventricular ejection fraction was not significantly different between groups (35%±8% vs. 35%±7%, P=0.2). However, after a mean follow-up of 21±7 months, left ventricular ejection fraction was significantly higher in vascularized patients (41%±5.8% vs. 34%±8%, P=0.01, respectively). Six of 7 patients had patent LAD grafts on CTA at 1-year follow-up.Conclusion:
CTA may provide valuable information about chronically occluded LAD size and graftability when ICA is inconclusive.