Recurrent Unexplained Palpitations (RUP) Study: Comparison of Implantable Loop Recorder Versus Conventional Diagnostic Strategy Original Research Article

Objectives The aim of the study was to compare the diagnostic yield and the costs of implantable loop recorder (ILR) with those of the conventional strategy in patients with unexplained palpitations. Background In patients with unexplained palpitations, especially in those with infrequent symptoms, the conventional strategy, including short-term ambulatory electrocardiogram (ECG) monitoring and electrophysiological study, sometimes fails to establish a diagnosis. Methods We studied 50 patients with infrequent (≤1 episode/month), sustained (>1 min) palpitations. Before enrollment, patients had a negative initial evaluation, including history, physical examination, and ECG. Patients were randomized either to conventional strategy (24-h Holter recording, a 4-week period of ambulatory ECG monitoring with an external recorder, and electrophysiological study) (n = 24) or to ILR implantation with 1-year monitoring (n = 26). Hospital costs of the 2 strategies were calculated. Results A diagnosis was obtained in 5 patients in the conventional strategy group, and in 19 subjects in the ILR group (21% vs. 73%, p < 0.001). Despite the higher initial cost, the cost per diagnosis in the ILR group was lower than in the conventional strategy group (€3,056 ± €363 vs. €6,768 ± €6,672, p = 0.012). Conclusions In subjects without severe heart disease and with infrequent palpitations, ILR is a safe and more cost-effective diagnostic approach than conventional strategy.