# Cor triatriatum dexter in Dogs: A Silent Bystander or a Potential Time Bomb? A Focused Literature Review from a Professional Perspective

## TL;DR

This paper reviews cor triatriatum dexter in dogs, a rare heart defect that can range from silent to life-threatening, and discusses its diagnosis, treatment, and ethical implications.

## Contribution

The paper provides a professional, multidisciplinary perspective on CTD in dogs, integrating medical, legal, and ethical viewpoints.

## Key findings

- CTD can cause heart failure, cyanosis, or sudden death depending on the severity of the obstruction.
- The condition is often associated with other congenital cardiac anomalies.
- Advances in diagnostic techniques have increased awareness and understanding of CTD in veterinary medicine.

## Abstract

Cor triatriatum dexter (CTD) is an uncommon congenital anomaly consequent to an abnormal separation of the atrium during embryological development, determining the persistence of the fibromuscular membrane dividing the right atrium. Based on the severity of the obstruction determined by the membrane, the clinical signs may be silent or appear as heart failure, with consequent ascites, and if there are other associated congenital cardiac anomalies, they could manifest as cyanosis or sudden death. The aim of the present review is to give a professional perspective, considering the defect from different points of view.

Congenital heart diseases (CHDs) are structural anomalies present at birth, resulting from aberrant embryonic development. In veterinary medicine, CHDs are an important reason for disease and death in both dogs and cats. Their prevalence varies across species and breeds, with certain defects being more common in specific breeds due to genetic predisposition. In this article, we will focus specifically on cor triatriatum dexter (CTD), an uncommon congenital defect that involves the division of the right atrium into two chambers by a fibromuscular membrane. This malformation can have serious consequences, depending on the severity of the obstruction created by the membrane, and the presence of the often-associated congenital anomalies. It can range from mild, clinically silent anomalies to severe defects that result in heart failure, cyanosis, or sudden death. The present review aims to (i) explore the pathophysiology of CTD in dogs; (ii) outline the clinical scenario underlying the increased interest in CHDs by overviewing the evolution of appropriate diagnostic techniques and the treatment options available; and (iii) provide a discussion from a medical–legal and ethical point of view.