Ventricular arrhythmias in dogs undergoing splenectomy: a prospective study

Fifty dogs undergoing splenectomy for splenic masses (n = 40), torsion of the splenic pedicle (n = 5), and immune-mediated disease (n = 5) were evaluated preoperatively and and postoperatively for ventricular arrhythmias and the relationship between ventricular arrhythmia splenic disease. The ability of 1-minute electrocardiograms recorded every 6 hours (ECGs/q6hr) to detect ventricular arrhythmia was compared with continuous 48-hour Holter monitoring. Based on continuous Holter monitoring, splenectomized dogs had a high incidence (22 of 50) of rapid ventricular tachycardia. The incidence of rapid ventricular tachycardia was significantly higher in dogs with ruptured splenic masses (16 of 23) than without rupture (1 of 17) (P < .001). When the results of ECG/q6hr were compared with the results of continuous Holter monitoring ECG/q6hr was normal in 29% (4 of 14) of dogs with rapid ventricular tachycardia at > 3,000 ventricular extrasystoles (VE)/hr; 50% (4 of 8) of dogs with rapid ventricular tachycardia at 1,000 to 3,000 VE/hr and 100% (6 of 6) of dogs with 10 to 300 VE/hr without rapid ventricular tachycardia. Although dogs undergoing splenectomy had a high incidence of ventricular arrhythmias, one-minute ECGs/q6h were unreliable for detection of ventricular arrhythmias even when high-frequency extrasystoles occurred.