Left anterior descending artery

Function

The LAD descends the anterior interventricular groove, supplying the anterior wall of the left ventricle, the apex and the anterior two-thirds of the septum with its diagonal and septal branches. In 90% of hearts it is the vessel that supplies the bundle branches.

It is the most commonly occluded coronary — hence 'the widow-maker'. Its territory is so vital that severe proximal LAD disease combined with proximal circumflex disease is treated as 'left-main equivalent'.

Blood supply

Arises from the left coronary ostium behind the left aortic cusp.

Nerve supply

Autonomic vasomotor nerves.

Clinical relevance

Anterior STEMI

Acute LAD occlusion is the largest, deadliest infarct; ST elevation across V1–V4 and reciprocal change inferiorly localise it.

LAD stenting

The workhorse target of PCI — drug-eluting stents here have transformed anterior infarction outcomes.

Related conditions

• Coronary artery disease
• Heart attack (myocardial infarction)