Perioperative Arrhythmia of Unknown Etiology in a Cat: Infection Involvement?

Perioperative arrhythmias may be life-threatening if left untreated, and diverse etiologies should be considered. We encountered an arrhythmia of unknown etiology in a cat with a chronic urinary tract infection (UTI). A domestic short-hair (DSH) castrated male cat of unknown age sustained a torn urethra due to a traffic accident and underwent urethral-vesical fistula formation. Subsequently, the cat repeatedly experienced urinary retention and a lower streptococcal UTI was detected; therefore, urethral reconstruction and a button-type fistula were performed. The cat’s electrocardiogram (ECG) initially showed no abnormalities; however, five months later, the UTI worsened. Following the removal of the bladder catheter under general anesthesia, an increase in the ST segment of the ECG was observed. Ultrasonography revealed mild thickening of the ventricular muscle, and a 6-lead ECG showed alternating pulse and ST elevation. After six days of antimicrobial treatment, the left ventricular wall thickening improved, but ST elevation persisted. The catheter was then removed under general anesthesia. At the months follow-up, the arrhythmia completely resolved. In humans, bacterial infections and inflammation can cause myocarditis that may lead to arrhythmia. In this case, although a direct causal relationship could not be definitively established chronic UTI-associated inflammation was considered a possible contributing factor affecting myocardial conduction. Therefore, the risk of arrhythmia in the perioperative period should be considered not only for acute or severe infections such as sepsis, but also for chronic infections and inflammatory diseases.