Angiographic Evaluation of Coronary Bypass Graft Patency and Integrity

Graft Identification and Location

Document the origin of each bypass conduit—saphenous vein or free arterial grafts from the aorta, and internal mammary arteries from the subclavian artery—recording the exact aortic attachment site. American Heart Association guidance. 1
Confirm the distal target vessel (e.g., LAD, diagonal, obtuse marginal, RCA, posterior descending artery) and specify whether the anastomosis is proximal, mid, or distal along that vessel. American Heart Association guidance. 2

Determine for every graft whether it is patent, stenotic, or occluded; this is the most critical component of angiographic review. American Heart Association guidance. 3
In grafts that appear patent, evaluate the uniformity of contrast opacification from the proximal to the distal anastomosis to ensure uninterrupted flow. American Heart Association guidance. 1
Total occlusion occurs in 10–25 % of saphenous vein grafts within the first postoperative year, with vein grafts showing higher early occlusion rates than arterial conduits. American Heart Association and American College of Cardiology data. 4
Internal mammary artery grafts maintain >90 % patency at 10 years, making them markedly superior to vein grafts for long‑term durability. American Heart Association and American College of Cardiology data. 5

Systematically inspect both the proximal (aortic) and distal (coronary) anastomoses for any narrowing, stenosis, or technical defects. European Society of Cardiology recommendations. 6
Recognize that anastomotic complications are a leading cause of early graft failure and must be carefully identified. European Society of Cardiology recommendations. 7

Saphenous vein grafts develop accelerated atherosclerosis; at 10 years only 50–60 % remain patent, and only about half of those are free of atherosclerotic disease. American Heart Association and American College of Cardiology data. 4
Record whether any observed disease along the graft is focal (limited segment) or diffuse (extending over a longer segment). American Heart Association guidance. 2

Assess distal runoff into the native coronary artery beyond the graft anastomosis to verify adequate perfusion. European Society of Cardiology recommendations. 6
Arterial grafts to vessels with <70 % stenosis on the left side or <90 % stenosis in the right coronary artery are prone to failure due to competitive flow. Guideline consensus (Praxis Medical Insights). 8

Compared with arterial conduits, saphenous vein grafts are more susceptible to early thrombosis and late atherosclerotic degeneration. American Heart Association and American College of Cardiology data. 5
Friable atherosclerotic plaques are present in ≈44 % of saphenous vein grafts, whereas native coronary arteries rarely exhibit such plaques. Guideline consensus (Praxis Medical Insights). 9

Internal mammary arteries demonstrate excellent long‑term patency (>90 % at 10–15 years). American Heart Association and American College of Cardiology data. 5
Their resistance to atherosclerosis is attributed to a continuous internal elastic lamina and favorable endothelial factors. American Heart Association data. 4

Muscular arterial conduits (e.g., radial artery) are prone to vasospasm, especially when grafted to coronary targets without severe stenosis. American Heart Association and Guideline consensus (Praxis Medical Insights). 8
These grafts should be reserved for severely stenotic vessels—≥70 % stenosis for left‑sided targets and ≥90 % for the right coronary artery. Guideline consensus (Praxis Medical Insights). 10

Identify coronary dominance by locating the origin of the posterior descending artery. American Heart Association guidance. 3
Document the progression of atherosclerotic disease in ungrafted native coronary segments. American Heart Association guidance. 1
Note any aneurysmal or pseudo‑aneurysmal dilations of native coronary arteries or grafts. American Heart Association guidance. 2
If ventriculography is performed, comment on left‑ventricular function. American Heart Association guidance. 1

Do not rely on a single angiographic projection; obtain multiple views to fully visualize graft course and anastomoses. American Heart Association guidance. 2
Avoid missing subtle anastomotic narrowing, which can precipitate early graft failure. European Society of Cardiology recommendations. 7
Do not overlook competitive flow as a cause of arterial graft failure, particularly when grafting vessels that are not critically stenosed. Guideline consensus (Praxis Medical Insights). 8