From the Guidelines
A Lima graft is a type of bypass graft used during coronary artery bypass surgery to restore blood flow to the heart, and it is considered the gold standard for coronary bypass grafting due to its excellent long-term patency rates and durability. This procedure involves taking the left internal mammary artery, which normally supplies blood to the chest wall, and redirecting it to bypass a blocked coronary artery, typically the left anterior descending artery. The LIMA graft is preferred over other types of grafts because of its superior durability, with over 90% remaining open after 10 years, as reported in the 2023 AHA/ACC clinical performance and quality measures for coronary artery revascularization 1. This superior durability occurs because the LIMA is an arterial graft rather than a venous one, making it more resistant to atherosclerosis. The LIMA's natural position in the chest also makes it ideal for this purpose, as it's already close to the heart and requires minimal manipulation during surgery. Additionally, the LIMA releases substances that help prevent blood clots and plaque formation, further contributing to its longevity. Some key considerations for the use of LIMA grafts include:
- Harvesting the internal mammary artery using the skeletonization technique to reduce the risk of sternal wound complications, as recommended in the 2021 ACC/AHA/SCAI guideline for coronary artery revascularization 1.
- Using the LIMA graft to target vessels with subocclusive stenoses, as it has been shown to improve cardiac event–free survival at 10 years 1. Patients receiving LIMA grafts typically experience better long-term outcomes, including improved survival rates and fewer repeat procedures compared to those receiving only vein grafts. For example, a study found that LIMA grafting reduced deaths, recurrent infarction, rehospitalization for cardiac events, and repeat revascularization, with substantially higher LIMA patency rates compared to saphenous vein grafts 1. Overall, the use of LIMA grafts is a crucial aspect of coronary artery bypass surgery, and their excellent long-term patency rates and durability make them the preferred choice for restoring blood flow to the heart.
From the Research
Definition of Lima Graft
- A Lima graft, also known as a Left Internal Mammary Artery (LIMA) graft, is a type of graft used in coronary artery bypass grafting (CABG) surgery 2.
- The LIMA is considered the "gold standard" for surgical revascularization due to its superior long-term patency rates and survival benefits compared to other grafts 2, 3.
Characteristics and Usage
- The LIMA is typically used to bypass the left anterior descending artery (LAD) and is considered a marker of quality control after CABG 2.
- The use of LIMA grafts has been steadily increasing worldwide, with over 90% of patients undergoing CABG receiving a LIMA graft to the LAD 2.
- LIMA grafts can be used in various configurations, including sequential anastomosis to the diagonal and LAD, and LIMA-LIMA "Y" grafts 3.
Benefits and Outcomes
- The use of LIMA grafts has been shown to improve long-term outcomes, including reduced mortality and morbidity, and improved cardiac-event-free survival 2, 3.
- LIMA grafts have been found to have superior patency rates compared to other grafts, including saphenous vein grafts 2, 4.
- The use of LIMA grafts is considered a safe and feasible alternative for complete revascularization of the anterior and lateral myocardial wall 3.