Left anterior descending

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Left anterior descending artery
Sternocostal surface of heart. Anterior descending branch labeled at upper right
Details
LocationHeart
SourceLeft main coronary artery
BranchesDiagonal branches, septal perforators
SuppliesAnterolateral myocardium, apex, interventricular septum, 45–55% of the left ventricle (LV)
Identifiers
Latinramus interventricularis anterior arteriae coronariae sinistrae
AcronymLAD
TA98A12.2.03.202
TA24143
FMA3862
Anatomical terminology

The left anterior descending artery (LAD), also called the anterior interventricular artery (IVA, or anterior interventricular branch of the left coronary artery)[1] is a branch of the left coronary artery. It supplies the anterior portion of the left ventricle.[2] It provides about half of the arterial supply to the left ventricle and is thus considered the most important vessel supplying the left ventricle. Blockage of the proximal LAD is often dubbed the "widow-maker" infarction due to its poor prognosis.[3]

Anatomy

Course

The LAD arises from the left main coronary artery just beyond the pulmonary artery. It advances to the anterior interventricular sulcus, along which it descends to the notch of cardiac apex. A common variant of the LAD, the "wraparound LAD," wraps around the apex and terminates on the posterior wall.[4]


Although rare, multiple anomalous courses of the LAD have been described. These include the origin of the artery from the right aortic sinus.[5]

Branches

The LAD gives off two types of branches: diagonal branches and septal perforators.

  • Septal perforators originate from the LAD, normal to the surface of the heart, perforating and supplying the anterior 2/3 of the interventricular septum.
  • Diagonals run along the surface of the heart and supply the lateral wall of the left ventricle and the anterolateral papillary muscle.

Segments

  • Proximal: from LAD origin to, and including, the origin of the first septal branch[6][7] (according to some definitions, to the first diagonal, or to whichever comes first).
  • Middle: from proximal segment to halfway of remaining distance to apex.[6][7] A more technical definition is from the proximal segment to the point where the LAD forms an angle, as seen from a right anterior oblique view on angiography, which is often close to the origin of the second diagonal branch.[8]
  • Distal: from middle segment to apex,[6][7] or in some cases beyond.[8]

Function

The artery supplies the anterior region of the left ventricle, including: the anterolateral myocardium, apex, anterior interventricular septum, and anterolateral papillary muscle.[9] The LAD typically supplies 45–55% of the left ventricle and is therefore considered the most critical vessel in terms of myocardial blood supply.

Left: Critical stenosis (95%) of the proximal LAD in a patient with Wellens syndrome.
Right: The same patient after reperfusion.

Disease

Pathologies associated with the LAD include atherosclerosis, which can lead to plaque rupture, artery occlusion and subsequent myocardial infarction (MI). The "widowmaker" heart attack is an MI in which the proximal LAD becomes occluded. This type of occlusion is severe given the large territory of myocardium supplied by the LAD, especially in patients with anomalous or wraparound LADs.

LAD occlusion is best diagnosed by 12-lead electrocardiogram (ECG).

References

Public domain This article incorporates text in the public domain from page 547 of the 20th edition of Gray's Anatomy (1918)

  1. Barbey, C.; Desveaux, B.; Quilliet, L.; de Labriolle, A.; Magdelaine, B.; Krsticevic, L.; Pacouret, G.; Charbonnier, B. (April 2005). "[Angioplasty at the bifurcation of the anterior interventricular artery and diagonal artery]". Archives des Maladies du Coeur et des Vaisseaux. 98 (4): 317–324. ISSN 0003-9683. PMID 15881848.
  2. Wilson, Alexander; Bhutta, Beenish S. (2022), "Anatomy, Thorax, Coronary Sinus", StatPearls, Treasure Island (FL): StatPearls Publishing, PMID 32491498, retrieved 2023-01-05
  3. Topol, Eric J.; Califf, Robert M. (2007). Textbook of Cardiovascular Medicine. Lippincott Williams & Wilkins. p. 283. ISBN 9780781770125. Retrieved 6 November 2014. The most worrisome type is the proximal left anterior descending (LAD) MI, often referred to as the widow-maker infarction, which carries a high mortality and is attributed to an occlusion of the LAD before or at the first septal perforator.
  4. Jindal, Himanshu; Fakoya, Adegbenro O. "Anatomy, Thorax, Heart Left Anterior Descending (LAD) Artery". NIH National Library of Medicine. National Institutes of Health. Retrieved 21 June 2026.
  5. Ropers, D. (12 February 2002). "Anomalous Course of the Left Main or Left Anterior Descending Coronary Artery Originating From the Right Sinus of Valsalva: Identification of Four Common Variations by Electron Beam Tomography". Circulation. 105 (6): 42e–43. doi:10.1161/hc0602.102020. PMID 11839639.
  6. Villa, AD; Sammut, E; Nair, A; Rajani, R; Bonamini, R; Chiribiri, A (28 June 2016). "Coronary artery anomalies overview: The normal and the abnormal". World Journal of Radiology. 8 (6): 537–55. doi:10.4329/wjr.v8.i6.537. PMC 4919754. PMID 27358682.
  7. Weber, C; Brown, KN; Borger, J (January 2020). "Anatomy, Thorax, Heart Anomalous Left Anterior Descending (LAD) Artery". PMID 30844189. {{cite journal}}: Cite journal requires |journal= (help)
  8. Kini, S; Bis, KG; Weaver, L (June 2007). "Normal and variant coronary arterial and venous anatomy on high-resolution CT angiography". AJR. American Journal of Roentgenology. 188 (6): 1665–74. doi:10.2214/AJR.06.1295. PMID 17515392.
  9. Wilson, Alexander; Bhutta, Beenish S. (2022), "Anatomy, Thorax, Coronary Sinus", StatPearls, Treasure Island (FL): StatPearls Publishing, PMID 32491498, retrieved 2023-01-05