Coil Embolization of the LIMA-LAD Graft Side Branch Through Radial Artery Access

Left internal mammary artery (LIMA) side branches to the chest wall are common, occurring in 9% to 25% of patients who have undergone CABG surgery. Large side branches are capable of substantial run-off, which can compromise flow to the distal internal mammary artery (IMA) by steal phenomenon. 

We present a case of coil embolization of the side branch of LIMA through the left radial artery access which provided symptomatic relief in our patient.

Case Presentation

A 47-year-old male with history of tobacco use and strong family history of coronary artery disease underwent coronary artery bypass graft (CABG) 6 months prior for a critical left main artery lesion. The patient had received left internal mammary artery-left anterior descending (LIMA-LAD), SVG-OM1, and SVG-OM2 grafts. The patient did not have symptom relief after the CABG. He continued to have angina symptoms with minimal exertion. It was decided with take him back to the cardiac catheterization lab due to continuing symptoms.

Left radial access was achieved using micropuncure technique. The angiogram showed patent SVG-OM1, SVG-OM2, and LIMA-LAD grafts. There was a large side branch of the LIMA graft supplying the thoracic wall (Figure 1; click image to enlarge). The diameter of the side branch was larger than the LIMA itself with poor distal flow to the LAD. It was decided to occlude the the LIMA side branch using coil embolization.

The LIMA was engaged with IMA 6 Fr Guide catheter. A microcatheter (Renegade Hi-Flo microcatheter, Boston Scientific) was introduced into the side branch and three Tornado Embolization Microcoils (Cook Medical), 5.0 mm x 2.0 mm; 3.0 mm and 3 mm x 2 mm were deployed, completely interrupting the flow. Final angiogram showed brisk filling of the LIMA and distal LAD (Figure 2; click image to enlarge). The patient was discharged home the same day and had complete resolution of symptoms at the 1-week follow-up visit.