Novel cutaneous use of implantable loop recorders in two dogs with unexplained episodes of collapse

Determining the cause of episodes of collapse can be difficult. Even in patients with frequent collapsing episodes due to cardiac causes, diagnostic surface electrocardiogram and 24 hr ambulatory electrocardiographic (Holter) monitoring are sometimes inconclusive. Event monitors with multiple leads can be challenging to use in veterinary medicine over long periods of time due to lead dislodgment. Implantable leadless loop recorders (ILRs) are useful, but owners are sometimes unwilling to have an ILR implanted due to the associated risks and/or costs. In this case report, the authors describe the use of cutaneously placed ILRs in two dogs with unexplained episodes of collapse/exercise intolerance. Data recorded provided clinically useful information. Cutaneously placed ILRs can be used effectively in veterinary medicine to evaluate patients with unexplained episodes of collapse.