Thoracic Trauma Causing an Acquired Gerbode Defect, Aortic Sinus Rupture, and Third-Degree Atrioventricular Block With Secondary Endocarditis in a Dog.

• Gerbode defects are high-velocity, systolic LV-RA shunts. • Gerbode defects are rare across species; the most common etiology is acquired. • IE and arrhythmias can be fatal complications of Gerbode defects. • Aortic sinus rupture may be traumatic in origin in the dog.