Implantation of a LUX-Dx insertable cardiac monitor enables remote heart rhythm monitoring in dogs and cats

INTRODUCTION/OBJECTIVES: Remote long-term rhythm monitoring enables arrhythmia diagnosis and treatment evaluation without in-clinic visits. This prospective case series evaluated the safety, feasibility, and clinical utility of the insertable cardiac monitor LUX-Dx™ and LUX-Dx II/II+™ in dogs and cats. ANIMALS, MATERIALS AND METHODS: Patients were divided into two groups. The diagnostic group included patients with unexplained intermittent clinical signs potentially caused by arrhythmia. The therapeutic group included patients with known arrhythmias requiring assessment of arrhythmia burden and treatment efficacy. Data were analyzed using the LATITUDE Clarity platform. Electrocardiography strips and tachograms were recorded during tachycardia, during bradycardia, or when triggered by owners. The device continuously registered mean heart rates. RESULTS: The device was implanted in 15 dogs and three cats with a 100% success rate and no complications. All procedures were performed under local anesthesia without sedation or general anesthesia. One-lead electrocardiography tracings were sufficient for rhythm interpretation, and remote monitoring and programming were successful in all patients. Clinically useful information contributed to rhythm diagnosis in 8 of 10 diagnostic patients and supported treatment decisions in all therapeutic patients, although changes in arrhythmia burden were not interpreted as proof of clinical benefit or improved prognosis. In two diagnostic cases, the absence of symptom recurrence with normal rhythm data limited conclusions. STUDY LIMITATIONS: Occasional sensing artifacts and misclassification of atrial arrhythmias occurred but were manageable through remote reprogramming. CONCLUSIONS: The LUX-Dx™ and LUX-Dx II/II+™ insertable cardiac monitors enable implantation without general anesthesia and remote monitoring in dogs and cats, providing clinically relevant rhythm data.