A 7-year-old 4.7-kg (10.3-lb) neutered male Russian Blue cat was examined by the referring veterinarian because of lethargy and inappetence of 2 days' duration. Cardiac auscultation revealed the only abnormality identified during physical examination, which was an irregular cardiac rhythm with a frequency of approximately 300 beats/min and interrupted with periods of distinctly lower (albeit undocumented) frequency. The cat had no history of cardiac abnormalities. The cat was immediately referred to the emergency service of a veterinary teaching hospital.
At the referral evaluation, the cat was bright, alert, and responsive and had a body condition score of 5/9. No signs of respiratory distress were evident; respiration was costoabdominal in nature at a frequency of 42 breaths/min. The femoral pulses were fair, regular, symmetric, and synchronous with the heartbeat; pulse rate was 210 beats/min. Cardiac auscultation revealed a regular rhythm with a frequency of 210 beats/min; no murmur or gallop was detected. The cat's mucous membranes were pink with a capillary refill time < 1 second. The rectal temperature was 38.6°C (101.5°F).
The initial diagnostic evaluation of the cat included clinicopathologic analyses. The results of a CBC were unremarkable. Plasma biochemical abnormalities included mild hypokalemia (3.1 mmol/L; reference range, 3.4 to 5.2 mmol/L), mild hypocalcemia (2.25 mmol/L; reference range, 2.36 to 2.86 mmol/L), mild hypophosphatemia (0.77 mmol/L; reference range 0.89 to 2.05 mmol/L), and mild hyperproteinemia (79 g/L; reference range, 54 to 70 g/L). Standard 6-lead ECG was performed for evaluation of the previously identified tachyarrhythmia.
The author thanks Karin Koelewijn for recording the ECG tracings.
- 1. ↑
Harvey AM, Faena M, Darke PG, et al. Effect of body position on feline electrocardiographic recordings. J Vet Intern Med 2005;19:533–536.
- 2. ↑
Santilli R, Moise NS, Pariaut R, et al. Supraventricular tachycardias. In: Santilli R, Moise NS, Pariaut R, et al., eds. Electrocardiography of the dog and cat. 2nd ed. Milano, Italy: Edra SpA, 2018;145–188.
- 3. ↑
Ozeke O, Guler V, Ilkay E. Ventricular pseudo-bigeminy pattern associated with Wolff-Parkinson-White syndrome. Emerg Med J 2009;26:877.