We successfully treated chronic type A dissection and coronary artery disease with a functional midline crossing right internal thoracic artery (RITA) after coronary artery bypass grafting (CABG). A 68-year-old man was incidentally diagnosed as chronic type A dissection by follow-up cardiac catheterization after CABG, with 90% stenosis in the right coronary artery (RCA) No. 2. The dissecting aneurysm (max. 6 cm in diameter) was localized at the right portion of the ascending aorta with a functional RITA to the left anterior descending coronary artery. The dissecting aneurysm was treated with patch closure and the RCA was revascularized with a right gastroepiploic artery and saphenous vein composite graft through combined right antero-axillar thoracotomy and lower mini-sternotomy without RITA dissection. Treatment of chronic type A dissection following CABG becomes more challenging with a functional midline crossing RITA. It is important that a safe and less invasive surgical strategy be implemented for such complicated case.