Hypoplastic left anterior descending artery

A hypoplastic left anterior descending artery (LAD) refers to a luminal narrowing or a short course of the left anterior descending artery.

Epidemiology

Not many cases of a hypoplastic left anterior descending coronary artery are described in the literature.

Associations

Clinical conditions associated with a hypoplastic left anterior descending coronary artery include other congenital coronary artery anomalies such as a super dominant circumflex artery ^1-4.

Clinical presentation

Like other types of coronary hypoplasia, a hypoplastic left anterior descending coronary artery can initially present as syncope, angina, sudden cardiac death or as an incidental finding on imaging studies ^1-4.

Complications

A hypoplastic left anterior descending artery can lead to the following conditions ^1-4:

• myocardial ischaemia
• myocardial infarction (MINOCA)
• arrhythmia
• sudden cardiac death

Radiographic features

Hypoplasia is defined by a short course and a narrow vessel lumen of the whole or a part of the left anterior descending artery and can be depicted with coronary CTA, coronary MRA or invasive coronary angiography ^1-4. A vessel diameter of less than 1.5 mm has been suggested ⁵.

Radiology report

The radiological report should include a description of the following features:

• left anterior descending artery with its course and branch anatomy
• the hypoplastic segment with location based on the AHA coronary artery segment model
• left main coronary artery origin and variant anatomy
• circumflex artery with its course and branch anatomy
• right coronary artery origin, course and branch anatomy
• any associated coronary artery anomalies
• coronary artery disease and stenoses

Treatment and prognosis

Due to an increased risk of arrhythmia, the implantation of an implantable cardioverter-defibrillator (ICD) has been recommended ¹.

Differential diagnosis

The differential diagnosis of a hypoplastic left anterior descending artery includes the following:

• myocardial bridging
• coronary artery disease: usually associated with plaque formation
• coronary vasospasm