Left anterior descending (anterior interventricular) artery
Main artery
Continues from the left main down the anterior interventricular groove to the apex, giving diagonal and septal branches; a long LAD may wrap round the apex to supply the inferior apical wall.
Traced from the start
- Left (posterior) aortic sinus and left main stem
- Left anterior descending (anterior interventricular) artery
Detail
- Branches
- Diagonals (D1, D2) to the anterolateral wall; septal perforators (S1, S2) into the septum
- Supplies
- Anterior LV wall, apex, anterior two-thirds of septum, right bundle branch and left anterior fascicle, part of the anterolateral papillary muscle
- Share of LV
- Largest single territory, about 45 to 55% of LV mass
When it goes wrong
Proximal LAD occlusion
Anterior STEMI in V1 to V4, extending to I, aVL, V5 and V6 when proximal to D1; largest infarcts, LV failure and cardiogenic shock
Critical proximal LAD stenosis in a pain-free patient (Wellens syndrome)
Biphasic or deeply inverted T waves in V2 and V3 with minimal troponin rise; needs angiography, not a stress test
Practise this structure
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