Introduction

• Rare condition.
• Peritoneal-pericardial diaphragmatic hernia (PPDH) is a congenital communication remaining between the pericardial and peritoneal spaces, through the diaphragm.
• Other congenital defects may be present, eg umbilical hernia, sternal deformity or ventricular septal defect Ventricular septal defect.
• Signs: usually referable to the respiratory or gastrointestinal systems. 
• Frequently the patient is asymptomatic and PPDH is found as an incidental finding.
• Diagnosis: radiography, ultrasonography.
• Treatment: surgical correction is indicated if the patient is symptomatic. Surgical repair should be performed as early as possible in young animals.
• Prognosis: good following surgical correction.

Pathogenesis

Etiology

• Embryological failure of diaphragm development - failure of closure of septum transversum or lateral pleuro-peritoneal folds.

Predisposing factors

General

• Other family members affected.

Specific

• Occasionally trauma can precipitate development of clinical signs - presumably by causing further herniation of abdominal organs, but trauma in and of itself is not a cause of PPDH.

Pathophysiology

• Embryological failure of normal development of the diaphragm.
• May affect septum transversum or lateral pleuro-peritoneal folds.
• Communication between pericardial and peritoneal cavities.
• If large enough defect, herniation of abdominal contents may occur into pericardial sac.
• Herniation of the liver or gall-bladder may not result in symptoms or signs; occasionally vague malaise, vomiting, inappetence, weight loss.
• Herniation of gastrointestinal tract usually results in symptoms, with vomiting, inappetence and weight loss to variable severity.
• Rarely, an entrapped liver lobe may cause a transudate, and pericardial effusion results in signs of compliance failure.

Timecourse

• Many patients may be asymptomatic for life.
• Once clinical signs develop, tend to be slowly progressive if defect not corrected.

Diagnosis

Treatment

Prevention

Outcomes