Incidence and Predictors of Symptom-Arrhythmia Association During Outpatient Holter Monitoring

Reported symptomatic activations by patients who are prescribed Holter monitors (Mortara Instrument, Baxter, Illinois, USA) often do not correlate with true arrhythmia, and recorded ectopy is often asymptomatic. The goal of this study is to describe the prevalence of symptom-arrhythmia association and its relation with age, sex, and underlying co-morbidities.

In this retrospective chart review, extended Holter recordings (analyzable data >72 hours) from 100 consecutive patients (April to July, 2023) were selected. Patients activated the monitor when they experienced an arrhythmia-related symptom. Accuracy was defined as the percent of activations associated with arrhythmia (atrial premature beat, ventricular premature beat, supraventricular tachycardia, ventricular tachycardia, 2nd/3rd degree atrioventricular block, or sinus exit block). We defined "symptom-arrhythmia association" as accuracy greater than zero.

For 100 patients (mean age: 55±18, 27% male), the average accuracy was 22%. Of the 100 patients, 42 had a symptom-arrhythmia association. On univariate analyses, patients with symptom-arrhythmia association were more likely to be older, have a lower left ventricular ejection fraction (LVEF), and be on cardioactive medications. None of these correlations was significant after multivariable adjustment.

Symptom-arrhythmia association is poor in humans. There are no significant differences by sex, percent Caucasians, presence of mitral valve prolapse, or the number of symptomatic activations in those with symptom-arrhythmia association versus those without.