Objective—To evaluate the disease-free interval (DFI) and median survival time (MST) in dogs with idiopathic and neoplastic pericardial effusion surgically treated by a thoracoscopic pericardial window procedure or subtotal pericardectomy via thoracotomy and to compare DFI and MST in dogs with and without a mass on preoperative echocardiography that underwent either surgical technique.
Design—Retrospective cohort study.
Animals—58 dogs with pericardial effusion.
Procedures—Medical records between 1985 and 2010 were evaluated. Dogs were included in the study if they had confirmed pericardial effusion and underwent a thoracoscopic pericardial window procedure or subtotal pericardectomy via thoracotomy.
Results—Clinical signs of dogs at initial evaluation were similar, with the exception of lethargy, between dogs treated by subtotal pericardectomy via thoracotomy or the pericardial window procedure. Dogs with idiopathic pericardial effusion that underwent the thoracoscopic pericardial window procedure had significantly shorter DFI and MST than did those treated by subtotal pericardectomy via thoracotomy. For neoplastic pericardial effusion, DFI and MST were not significantly different between dogs treated with either surgical technique.
Conclusions and Clinical Relevance—Dogs with idiopathic pericardial effusion treated with a subtotal pericardectomy via thoracotomy had a significantly longer DFI and MST, compared with dogs treated by the thoracoscopic pericardial window procedure. This difference in outcome may be related to inaccuracy of the initial diagnosis or ineffectiveness of the pericardial window to palliate the signs of idiopathic pericardial effusion long term.
Case Description—A 6-year-old castrated male Llewelyn Setter was evaluated because of an acute onset of myalgia and respiratory distress.
Clinical Findings—Physical examination revealed a stiff stilted gait, swollen muscles that appeared to cause signs of pain, panting, and ptyalism. The dog had a decrease in palpebral reflexes bilaterally and a decrease in myotatic reflexes in all 4 limbs. The panniculus reflex was considered normal, and all other cranial nerve reflexes were intact. Serum biochemical analysis revealed markedly high cardiac troponin-I concentration and creatine kinase and aspartate aminotransferase activities. Urinalysis revealed myoglobinuria. Results for thoracic and abdominal radiography, blood pressure measurement, and an ECG were within anticipated limits. Echocardiographic findings were consistent with secondary systolic myocardial failure. Arterial blood gas analysis confirmed hypoxemia and hypoventilation. The dog had negative results when tested for infectious diseases. Examination of skeletal muscle biopsy specimens identified necrotizing myopathy.
Treatment and Outcome—Treatment included ventilatory support; IV administration of an electrolyte solution supplemented with potassium chloride; administration of dantrolene; vasopressor administration; parenteral administration of nutrients; use of multimodal analgesics; administration of clindamycin, furosemide, mannitol, and enrofloxacin; and dietary supplementation with L-carnitine and coenzyme Q10. Other medical interventions were not required, and the dog made a rapid and complete recovery.
Clinical Relevance—Necrotizing myopathy resulting in rhabdomyolysis and myoglobinuria can lead to life-threatening physical and biochemical abnormalities. Making a correct diagnosis is essential, and patients require intensive supportive care. The prognosis can be excellent for recovery, provided there is no secondary organ dysfunction.