[Value of "cardiac event recorders" in the assessment of sporadic cardiac symptoms].

Objectives: To determine the value of the Cardiac Event Recorder (CER) in the diagnosis and treatment orientation of bradydysrhythmias, tachydysrhythmias and ischaemic events, based on our experience at the Santa Cruz Hospital.

Methods: We retrospectively analysed 100 consecutive patients tested with a CER between January 1990 and December 1996 (mean follow-up, 272 +/- 202 days); the mean age of the patients (66 women and 34 men) was 45 +/- 18 years (range: 7 to 83); structural cardiac disease was present in 34% of the patients. CER was indicated for the investigation of symptoms suggestive of bradydysrhythmias (pre-syncope and/or syncope)--Group B--in 24 patients, tachydysrhythmias (palpitations and/or tachycardia sensation)--Group T--in 72 patients and ischaemic events--Group I--in the remaining four patients. We compared these groups with respect to demographic characteristics, prevalence of structural cardiac disease and efficacy of the test in the investigation of symptoms; periodicity of symptoms and duration of CER testing were analysed. In patients that experienced typical symptoms during the test, we analysed the electrocardiogram recorded at the time of the event and we investigated whether abnormal ECG findings influenced the therapeutic approach and whether this led to better symptomatic outcome.

Results: Patients in groups B and T were mainly women (54 percent vs 74 percent, NS). Group B patients were older than group T patients (mean age, 56.4 +/- 17.8 vs 40.0 +/- 16.0 yrs, P < 0.001). In group B, structural cardiac disease was less prevalent (37.5% vs 78.0%, P < 0.001) and symptom periodicity was greater (weekly: 12.5% vs 78.0%, monthly: 87.5% vs 15.2%, P < 0.001) than in group T. Duration of CER testing and number of events recorded were similar in the two groups. In both, CER testing was an important aid for therapeutic approach. Twenty two patients (eight B, 13 T and one I) had no typical symptomatic episodes during the CER test; in the remaining 78 patients (16 B, 59 T and three I), an electrocardiogram recording during such episodes was available for analysis. The ECG was abnormal in 44 of these patients, 12 (75%) being of group B and 32 (54%) of group T. Symptom periodicity was a few weeks in 65% of all patients (6 B, 57 T and two I). Duration of CER testing was < or = two weeks in 91 percent of the patients (22 B, 65 T and four I). CER testing guided the therapeutic approach in 78% of all patients. Changes of treatment strategy were more frequent in patients with CER documented typical symptomatic episodes than in those without (46% vs 9%, P < 0.02). When changes of treatment occurred, symptomatic outcome was better (97% vs 55%, P < 0.001).

Conclusions: The CER is an important guide for the diagnostic and therapeutic approach for patients with intermittent arrhythmia suggesting, symptoms (78% of patients). A recording of normal ECG during typical symptoms reassures the patient and excludes potentially toxic treatments. Our selection of patients for CER testing seemed adequate since most typical symptomatic events occurred during the first two weeks of the test; longer duration of CER testing seems unnecessary.