Comparison of in-hospital continuous electrocardiography versus recordable Holter monitoring in dogs with ventricular arrhythmias.

Abstract

OBJECTIVE: Determine the agreement between nonrecordable continuous ECG and Holter monitoring at estimating arrhythmia severity in hospitalized dogs. DESIGN: Prospective, observational, cohort study. SETTING: University teaching hospital. ANIMALS: Ten dogs. INTERVENTIONS: Heart rates and rhythms were simultaneously monitored using nonrecordable cage-side continuous ECG and Holter monitoring. Continuous ECG was assessed by ICU technicians for 1 min every hour, and heart rate and rhythm were recorded. A modified Lown score was used to grade arrhythmia severity (Grade 0 = sinus; Grade 1 = single ventricular premature complexes; Grade 2 = accelerated idioventricular; Grade 3 = bigeminy/trigeminy; Grade 4 = couplets/triplets; Grade 5 = ventricular tachycardia or R on T). Holter data were analyzed by a board-certified cardiologist, and arrhythmia grade was assigned to the same 1-min time period reported by ICU technicians. A 1-h arrhythmia grade was also determined from Holter data and was reported as the highest grade noted during the previous hour. Cohen's weighted kappa analysis was used to compare the agreement of ICU and Holter grade during the same 1-min time period and to compare 1-min Holter grade with the prior hour Holter grade. MEASUREMENTS AND MAIN RESULTS: Weak agreement was found between ICU-reported grade and Holter grade (κ = 0.40), as well as weak agreement between 1-min Holter grade and hour Holter grade (κ = 0.39). CONCLUSIONS: Results of this study indicate that arrhythmia grades assessed by ICU technicians and hourly 1-min observations weakly agree with recordable Holter monitoring in hospitalized dogs with ventricular arrhythmias.