Report of Conduction Disturbance with Ventricular Septal Defect in a Dog

Abstract

Nine months old Shiba dog (Male) was referred to our Institute. The dog suffered from four episordes of syncopal attack during 6 to 8 months of age.
On auscultation, holosystolic regurgitant murmur was best heard along the right sternal border at the fourth intercostal space. The electrocardiogram (ECG) showed occasional second degree atrioventricular block and sinoatrial arrest. His bundle electrogram and atrial pacing revealed prolonged P-H interval but without sinus node abnormality. Angiocardiogram demonstrated membranous septal defect.
ECG of his parents and three littermates disclosed first degree atrioventricular block in his father and one of the littermates, therefore, we considered that this disturbance might be hereditary heart block.