Pericarditis:

• Pericarditis simply refers to inflammation of pericardium- outer layer of heart.
• It may be acute or chronic in nature.
• Pericarditis may be traumatic, fibrinous, effusive or adhesive depending on nature of inflammation.
• Traumatic pericarditis is widely prevalent in cattle due to higher incidence of ingestion of foreign objects in grass or straw.

Types of pericarditis:

1. Traumatic pericarditis:

• It occurs most commonly in cattle
• It is caused by trauma to pericardium due to perforation of pericardial sac due to ingestion of foreign material
• This type of pericarditis is also recorded in horse and lamb, but are uncommon.

2. Effusive pericarditis:

• It is common form of acquired cardiovascular disease in dogs, uncommon in cattle and rare in cats.
• It is characterized by accumulation of protein rich fluid within pericardial sac.

3. Fibrinous pericarditis:

• In this type of pericarditis, fluid is replaced by fibrin. In chronic inflammatory process, fibrin starts to deposit around pericardium resulting in fibrinous pericarditis.
• It is also known as adhesive pericarditis.
• Parietal and visceral surface of pericardial sac gets adhesive.

Etiology:

• Trauma, injury, surgical incision
• Extension of infection from myocardium, pleurisy
• Bacterial infection:
  • Cattle: Mannheimia hemolytica, black disease, Haemophilus spp, Tuberculosis, Pseudomonas aeruginosa, Mycoplasma spp, Klebsiella pneumonia, Actinobacillus suis
  • Horses: Streptococcus equi, S. zooepidemicus, S. faecalis, Tuberculosis, Corneybacterium pseudotuberculosis, Actinobacillus equi,
  • Sheep and goat: Pasteurella spp, Staphylococcus aureus, Mycoplasma spp
  • Pigs: Pasteurellosis, Mycoplasma spp. especially Mycoplasma hyorhinis, Haemophilus spp. – Glasser’s disease and pleuropneumonia, Streptococcus spp., Salmonellosis
• Viral infection: EHV-1 infection, Feline infectious peritonitis, Canine distemper
• Fungal infection: Actinomycosis, coccidiodiomycosis

Clinical Findings:

• In early stages, there is
  • pain,
  • avoidance of movement,
  • abduction of elbows,
  • arching of back,
  • shallow abdominal respiration
• Pain is evident on percussion or firm palpation over cardiac area of chest wall
• Animal lies down carefully to avoid pain
• Pericardial friction sound is heard on auscultation which is replaced by muffled heart sounds later during effusion period
• Elevated temperature; 103-106°F
• Increased pulse rate
• If gas is present, each cardiac cycle is accompanied by splashing sounds on auscultation
• In second stage, there is marked increase in heart rate, severe toxemia, signs of congestive heart failure; edema of brisket region, marked jugular pulse, starts to develop.
• Animals usually die in secondary stage of pericarditis

Laboratory Findings:

• Marked leukocytosis and neutrophilia
• Hyperglobulinemia

Diagnosis:

• On basis of history and clinical findings
• On basis of laboratory findings
• Cytological examination of pericardial fluid
• ECG findings; sinus tachycardia, diminished amplitude of QRS complex,
• Radiography of thoracic region
• Echocardiography; most valuable aid in diagnosis, will show excessive fluid present in pericardial sac

Differential Diagnosis:

• Disease should be differentiated with;
  • Pleuritis
  • Cardiac valvular disease
  • Mediastinal abscess15
  • Hydropericardium occurs in congestive
  • heart failure, mulberry heart disease of pigs, herztod of pigs, gossypol poisoning,
  • Clostridial intoxications of sheep
  • Lymphomatosis

Treatment:

• Animals should be kept at rest.
• Broad spectrum antibiotics should be used based on susceptibility of organism cultured from pericardial fluid
• Combination of penicillin and gentamicin is commonly used to treat this condition.
• Pericardiocentesis; copious lavage with warmed 0.9% NaCl solution and drainage should be conducted as possible to relieve pressure form pericardium.
• Corticosteroid therapy or aggressive NSAID therapy is beneficial.
• Salt free diet should be provided.