Diagnostic yield of automatic and patient-triggered ambulatory cardiac event recording in the evaluation of patients with palpitations, dizziness, or syncope

Background: Recent studies have shown that patient-triggered cardiac event recorders (CER) have an increased diagnostic yield and are more cost effective than conventional 24-h-Holter electrocardiograms (ECGs) for the evaluation of sporadic, potentially arrhythmia-related symptoms. Hypothesis: The aim of this study was to determine the diagnostic yield of a patient-triggered CER combined with continuous automatic arrhythmia detection in the evaluation of sporadic dizziness/syncope or palpitations and its clinical relevance in assessing the further management. Methods: We investigated 101 consecutive outpatients (54 20 years, 40 women), referred for evaluation of sporadic dizziness and syncope (36%) or palpitations (64%) of suspected rhythmogenic origin. All were monitored by patient-triggered CER with continuous automatic arrhythmia detection. Results: After a mean monitoring period of 103 38 h, 83 patients registered symptoms and 57 patients had diagnostic or therapeutic relevant arrhythmias (relA). A total of 196 episodes of relA were recorded; 31 (16%) episodes were patienttriggered and 165 (84%) automatically recorded. Diagnostic relevant episodes (relA and/or typical symptoms) occurred in 94 patients, in 54% after the first 24 h of monitoring. According to the results of the CER, 80 patients needed no further diagnostic evaluation; 20 had additional diagnostic tests. Conclusions: Cardiac event recorders with a continuous automatic arrhythmia detection function are a well-tolerated device for sporadic, potentially arrhythmia-related symptoms. The patient-triggered mode alone is not sufficiently reliable; the automatic continuous arrhythmia detection function has additional diagnostic and therapeutic consequences. In 54% of all patients, the first diagnostic event would not have been recorded with a single conventional 24-h-Holter ECG.