Anomalous Left Main Coronary Artery: Not Always a Simple Surgical Reimplantation
Asif H Khan1, Ian B A Menown, Alastair Graham
1Craigavon Cardiac Centre, Southern Trust, Craigavon, BT63 5QQ, Northern Ireland, UK.
Insights
This case study highlights successful surgical management of anomalous left main coronary artery (LMCA) using grafts. A saphenous vein graft (SVG) provided adequate blood flow, demonstrating the benefit of grafting alongside reimplantation.
Area of Science:
- Cardiology
- Cardiac Surgery
- Vascular Surgery
Background:
- Anomalous left main coronary artery (LMCA) originating from the right coronary cusp presents a high-risk surgical challenge.
- Complex coronary artery bypass grafting (CABG) involving LMCA reimplantation requires careful consideration of graft patency and native vessel stenosis.
Purpose of the Study:
- To present a complex case of high-risk anomalous LMCA requiring surgical intervention.
- To evaluate the long-term patency and functional significance of grafts used in LMCA reimplantation.
- To illustrate the potential benefits of additional grafting in anomalous LMCA cases.
Main Methods:
- Coronary artery bypass grafting (CABG) with LMCA reimplantation, left internal mammary artery (LIMA) to LAD, and saphenous vein graft (SVG) to LCx.
- Postoperative assessment using cardiac computed tomography (CCT) and cardiac catheterization.
- Fractional flow reserve (FFR) measurement to assess ostial stenosis significance.
Main Results:
- The LIMA graft to the LAD occluded distally.
- The SVG graft to the LCx remained patent with good distal run-off and retrograde filling of the LAD.
- Moderate ostial stenosis of the reimplanted LMCA was present but not functionally significant (FFR 0.89) due to retrograde filling.
Conclusions:
- Saphenous vein grafts can provide adequate coronary perfusion in anomalous LMCA cases, even with distal LIMA graft occlusion.
- Careful hemodynamic assessment is crucial to avoid unnecessary interventions like stenting for non-significant ostial stenosis.
- Additional grafting strategies may benefit selected patients with anomalous LMCA beyond conventional reimplantation.
Abstract:
We present the case of 56-year-old woman who required complex coronary artery bypass grafting for high-risk anomalous left main coronary artery (LMCA) originating from right coronary cusp including conventional reimplantation of the LMCA plus left internal mammary artery (LIMA) graft to the left anterior descending (LAD) and saphenous vein graft (SVG) to the left circumflex (LCx). On subsequent cardiac computed tomography screening and cardiac catheterization, the LIMA graft was occluded after just a few centimeters, but the SVG graft was patent with good run-off into the native LCx and also filled the LAD retrogradely. The reimplanted left main stem demonstrated at least moderate ostial stenosis although pressure wire assessment of this was not significant (fractional flow reserve 0.89), probably due to good retrograde filling of the LAD from the SVG to LCx, therefore, we did not proceed with ostial LMCA stenting. She remains on yearly review with a low threshold for further revascularization should the SVG to LCx develop progressive stenosis. This case illustrates how patients with anomalous LMCA may sometimes benefit from grafting in addition to conventional reimplantation.
