ECG of the month. Cardiac tamponade secondary to A. niger-induced constrictive pericarditis

Canine leishmaniasis associated with pericardial effusion in a 4-year-old dog

A 4-year-old crossbreed dog presented with a two-day history of lethargy and abdominal effusion. Physical examination and echocardiography revealed pericardial effusion with cardiac tamponade. Pericardiocentesis was performed. Intracytoplasmic Leishmania amastigotes were found on cytological examination of the pericardial fluid. The animal was treated with N-methylglucamine antimoniate and allopurinol. After an initial favorable response, cardiac tamponade reoccurred one month later. The dog died during a pericardiectomy four months after the initial diagnosis. Histology confirmed the presence of chronic pericarditis. The presence of Leishmania amastigotes on cytological examination of pericardial effusion suggests a possible association between canine leishmaniasis and chronic pericarditis. This finding also supports the importance of cytological examination of pericardial fluid in areas endemic for canine leishmaniasis.

Fungal myocarditis and pericardial effusion secondary to Inonotus tropicalis (phylum Basidiomycota) in a dog

Fungal disease is a rare cause of pericardial effusion in dogs. This report describes the first case of fungal pericardial effusion and myocarditis secondary to the fungal organism Inonotus tropicalis. A 9-year-old female spayed French bulldog with a multi-year history of treatment with glucocorticoids for management of atopy was presented for exercise intolerance, ascites and weight loss. Physical examination and thoracic imaging revealed enlarged peripheral and cranial mediastinal lymph nodes, left ventricular thickening and cardiac tamponade secondary to pericardial effusion. Fine needle aspiration of the cranial mediastinal lymph node showed pyogranulomatous inflammation with short, thin and poorly septated hyphae. Culture of the aspirate yielded a fungal isolate identified as Inonotus tropicalis based on morphologic features and rRNA gene sequencing. Postmortem examination showed myocardial thickening with multifocal to coalescing, firm, white, ill-defined nodules. Histology confirmed the presence of disseminated fungal infection with extensive myocardial involvement. Inonotus tropicalis is an opportunistic poroid wood-decaying basidiomycete. Infection in this dog was likely the result of chronic immunosuppressive therapy.

Use of Procainamide for Conversion of Acute Onset AF Following Pericardiocentesis in a Dog

A 9 yr old spayed female golden retriever was evaluated for anorexia and suspected gastric dilatation. Subsequent evaluation the following day determined the dog to have pericardial effusion. Muffled heart sounds and jugular pulses were noted on physical exam, and the dog was diagnosed with pleural and pericardial effusion. A sinus rhythm with a rate of 142 beats/min was documented on a surface electrocardiogram (EKG). Following pericardiocentesis, the heart rate increased to 260 beats/min, the rhythm became irregular, and the systemic blood pressure decreased. Atrial fibrillation (AF) was confirmed by EKG. Procainamide was administered IV over 15 min, resulting in successful conversion of AF to sinus rhythm and clinical improvement. Procainamide is one of several antiarrhythmic medications that are used for the conversion of acute AF in humans; however, its utility and efficacy in dogs in the setting of AF has not previously been reported. This case highlights a unique complication of performing a pericardiocentesis that requires immediate treatment and describes a potential treatment option for the conversion of acute AF in dogs.

Purulent pericarditis in a dog administered immune-suppressing drugs

A 5-year-old castrated mongrel dog was brought to our hospital with anorexia and vomiting. Laboratory testing revealed immune-mediated hemolytic anemia (IMHA), and so treatment was initiated with multiple immune-suppressing drugs, achieving partial remission from IMHA. However, cardiac tamponade due to purulent pericarditis was identified as a secondary disease. Culture of pericardial fluid yielded numerous Candida albicans and multidrug-resistant Acinetobacter sp. Pericardiocentesis was performed, and the condition of the dog improved. However, the dog died the next day.