Equine Aortic Rupture Study Guide

Overview and Clinical Importance

Aortic rupture is a catastrophic cardiovascular emergency in horses characterized by complete tear through all layers of the aortic wall, leading to massive hemorrhage and sudden death. This condition represents one of the most important causes of sudden death in horses and is a high-yield topic for the NAVLE examination.

The condition occurs most frequently in two distinct patterns: aortic root rupture near the sinuses of Valsalva in older breeding stallions during or after coitus, and aortic arch rupture near the ligamentum arteriosum in young to middle-aged Friesian horses. Understanding these breed-specific and location-specific patterns is essential for clinical practice and board examination success.

Epidemiology and Breed Predisposition

General Prevalence

Aortic rupture is relatively rare in the general equine population, with approximately 5 horses dying annually from this condition based on literature reviews spanning 28 years. However, incidence varies dramatically by breed, with Friesian horses showing significantly higher prevalence.