Balloon dilation of a perforated cor triatriatum dexter in a Springer Spaniel: anaesthetic management

SUMMARY A four‐month‐old male Springer Spaniel presented for investigation of ascites of three weeks’ duration. On transthoracic echocardiogram, cor triatriatum dexter was diagnosed with associated right‐sided congestive heart failure. Medical therapy consisting of furosemide, spironolactone and benazepril was initiated. On the day of surgery, the dog was premedicated with methadone 0.2 mg/kg intravenously, and general anaesthesia was induced with midazolam 0.2 mg/kg intravenously and propofol 25 mg. Anaesthesia was maintained with isoflurane in oxygen. Concurrently, constant rate infusions of fentanyl 0.2–0.3 µg/kg/minute and lidocaine 50 µg/kg/minute were administered. Ventricular premature complexes and ventricular tachycardia developed during the placement of the catheter and during the first balloon dilation. Antiarrhythmic therapy with lidocaine 2 mg/kg was required. At the end of the procedure, acepromazine 5 µg/kg intravenous and buprenorphine 20 µg/kg intravenous were administered. Recovery from general anaesthesia was uneventful.