Event-Rekorder

Event or loop recorders monitor heart rhythm using discontinuous ECG storage which enables them to obtain a correlation between symptoms and the underlying heart rhythm in patients with infrequent, short-lasting episodes. External event recorders with intermittent monitoring, i.e., with electrodes within the device, are suitable for patients with palpitations or tachycardia who remain conscious. External event recorders with continuous monitoring are tolerated by patients for a few weeks and have a limited diagnostic impact in patients with recurrent syncope. The implantable loop recorder (ILR) monitors heart rhythm for one year and after patient-triggered or automatic activation stores a one-lead ECG up to 42 minutes prior to device activation. The diagnostic benefit of ILR in comparison to conventional approaches has been demonstrated in randomised studies. Furthermore, an ILR identifies patients with recurrent syncope of unknown origin in whom a pacemaker implantation can avoid further episodes. Additional possible indications are the monitoring of atrial fibrillation, the diagnostics of infrequent palpitations and patients with seizures.     

Prospective comparison of the diagnostic utility of a standard event monitor versus a “leadless” portable ECG monitor in the evaluation of patients with palpitations

INTRODUCTION: Current ambulatory ECG monitoring systems are limited in their ability to diagnose patients with palpitations. The aim of this prospective study was to compare a new "leadless" ambulatory monitor with a standard event monitor in the evaluation of patients with palpitations. METHODS: Eighteen consecutive patients (11 female, 56 +/- 16 years) referred for evaluation of palpitations were provided with both a standard event monitor and a "leadless" monitor for 30 days. They were asked to record episodes of palpitations with both monitoring devices. RESULTS: All 18 individuals were compliant with the "leadless" monitor for the 30-day period while only 14 (78%) patients were compliant with the standard event monitor (p = 0.10). During a combined monitoring period of 563 days, 159 symptomatic episodes were recorded with the "leadless" ECG monitor (8.8 +/- 9.7 per patient, range 1-35) and 169 symptomatic episodes were recorded with the event monitor (12 +/- 8.3 per patient, range 1-33) (p = NS). The "leadless" ECG monitor recorded arrhythmias in 13 of 18 patients (72%) and the standard event monitor recorded arrhythmias in 8 of 14 patients (57%) (p = NS). CONCLUSION: The "leadless" ECG monitor is associated with high patient compliance and results in high quality ECG recordings. The diagnostic yield of this monitoring system is equivalent to a standard event monitor.     

Diagnostic management of patients with palpitations of unknown origin.

The first-line investigations in the diagnostic management of patients with palpitations include history taking, physical examination and ECG. These investigations yield a definitive or probable diagnosis in a good proportion of patients. If the patient is suffering from heart disease, or if the palpitations are frequent or poorly tolerated, ambulatory ECG monitoring and electrophysiological study should be undertaken. Holter monitoring (useful when symptoms occur daily) has a rather low sensitivity, while event recorders (useful in compliant patients with infrequent palpitations that are fairly long-lasting) and external loop recorders (recommended in cases of infrequent short-lasting palpitations associated with hemodynamic impairment) have proved to have a higher sensitivity. The diagnostic yield of the electrophysiological study (generally recommended when the recording attempts using ambulatory ECG monitoring fail to provide a diagnosis) depends on the stimulation protocol used, the clinical characteristics of the patients studied, and the type of arrhythmias induced. Implantable loop recorders may be recommended in patients with rare, highly symptomatic palpitations associated or not with hemodynamic impairment, when the other diagnostic modalities prove to be inconclusive.     

Automatic Cardiac Event Recorders Reveal Paroxysmal Atrial Fibrillation after Unexplained Strokes or Transient Ischemic Attacks

Background: The etiology of stroke or transitory ischemic attack (TIA) remains frequently unknown. While paroxysmal atrial fibrillation (PAF) is often suspected, its presence remains difficult to establish. Therefore, we investigated the occurrence of PAF episodes in such a population using a long‐term automatic cardiac event recorder. Methods: We prospectively investigated 60 consecutive subjects admitted in our university hospital for stroke (n = 44) or TIA (n = 16) , adding long‐term automatic cardiac event recorders, with a target duration of 4 days, to standard investigations, which included 12‐lead ECGs and 24‐hour Holter recordings. Results: In 28 patients no etiology was found for their stroke or TIA. However, one or more than one PAF episode was found in 4 of them (14.3%) using the long‐term automatic event recorder. In the 32 remaining patients, 8 presented with PAF, and this was considered as the cause of their stroke. In both groups, AF was paroxysmal. The PAF episodes' duration went from 1 to 96 hours (mean ± standard deviation, 18 hours and 30 minutes ± 30 hours). Conclusions: Patients suffering PAF episodes after ischemic stroke or TIA were statistically less often recognized using the 24‐hour Holter ECG recording alone than the R‐Test Evolution alone.     

Cardiac event recorder yields more diagnoses than 24-hour Holter monitoring in patients with palpitations]

BACKGROUND: Palpitations are a common symptom that sometimes results from a substantial cardiac arrhythmia. A 24-hour Holter monitoring is usually used, but the yield of this instrument is low in patients whose symptoms occur infrequently. The aim of this study was to compare the diagnostic yield and the cost-effectiveness of transtelephonic event recorder (TER) with those of Holter monitoring in patients with intermittent palpitations. METHODS: Three hundred and ten patients with intermittent palpitations were allocated to the study and randomly assigned to receive a TER or 24-hour Holter monitoring. TER was given to patients until recording was obtained while symptoms occurred or was used at most for 7 days. At enrollment, a basal trace was recorded. Patients with palpitations recorded the one lead ECG trace and sent it by phone (fixed or mobile) to the telemedicine call center where a trained nurse compared the trace with the basal one and checked the patient's symptoms. The cardiologist reported "on-line" all the traces sent in the presence of an arrhythmic event and "stored and forwarded" all the other traces. Standard methods were used for Holter recording and reading. RESULTS: Patients with palpitations during the examination were 119 (76.8%) in the group of TER and 74 (47.8%) in the Holter group (p < 0.000) with an efficacy increase of 29% for TER. In symptomatic patients there were no differences between the two groups about the presence or absence of arrhythmias checked in the ECG traces; the time necessary to make a presence/absence diagnosis of arrhythmias was 2.97 +/- 2.74 days with the event recorder. The total cost of 155 tests made with Holter was altogether 9605.35 Euro (costs per test 61.97 Euro), while the one of TER was 6019.2 Euro (cost par test 38.83 Euro). The cost-effectiveness analysis was 129.80 Euro for Holter and 50.57 Euro for TER, with a saving of 79.23 Euro for every diagnosis made. CONCLUSIONS: TER allows to detect intermittent palpitations in real time; it is more useful and effective than Holter; moreover this effectiveness was also confirmed by the cost analysis in which TER resulted less expensive.     

A multicentre trial of the diagnostic value and cost of electrocardiography in symptoms suggesting arrhythmia with a new event recorder with transtelephonic transmission

Events recorders are used for electrocardiographic documentation of symptoms of arrhythmia too sporadic and short lasting to be recorded by 24 hour Holter monitoring. However, there are no French studies comparing the value and cost of event recorders with conventional diagnostic methods. Recently, a new telediagnostic device has become available in France leading to an assessment of the technique. The aim of this study was to determine the value of this event recorder and the cost of diagnostic ECG in the assessment of presumed arrhythmic symptoms such as palpitations or rare tachycardia (<3 episodes per week) of short duration, compared with conventional techniques. Fifty-eight patients with these criteria were randomised, 30 to Survcard (Group I) and 28 to conventional diagnostic methods (Group II). The patients were comparable with respect to age, sex distribution, type of symptoms and associated cardiac disease. The ECG diagnosis of the symptoms was established in 20 cases (66.6%) of patients in Group I in 17 +/- 16 days, and in 14 cases (50.0%) of Group II in 23 +/- 28 days. The difference between the two groups was not statistically significant. The cost of a positive diagnosis for Group I (Survcard) varied from 0 to 228.47 Euro with an average of 71.22 +/- 117.02 Euro. The cost of positive diagnosis in Group II varied from 76.80 to 2340.41 Euro with an average of 480.39 +/- 797.41 Euro. In conclusion, this study showed that the percentage of patients with a positive diagnosis was comparable in the two groups but that the cost was 6 times higher in the group investigated by conventional methods than in the Survcard group because of more costly medical intervention.     

Incremental diagnostic yield of loop electrocardiographic recorders in unexplained syncope

The Holter monitor, the most frequently used diagnostic test in patients with syncope, is nondiagnostic in over 90% of cases. This study sought to determine the impact of a new noninvasive device, the cardiac loop electrocardiographic (ECG) recorder, after Holter monitoring in 57 patients with unexplained syncope. All patients underwent a standardized evaluation protocol and were the monitor for up to 1 month. In 14 patients, loop recording definitively determined whether an arrhythmia was the cause of symptoms (diagnostic yield 25%; 95% confidence intervals 14 to 38%). Diagnoses included unsuspected ventricular tachycardia (1 patient), high grade atrioventricular block (2 patients), supraventricular tachycardia (1 patient), asystole or junctional bradycardia from neurally mediated syncope (3 patients) and normal cardiac rhythms (the remaining 7 patients). Follow-up of all patients diagnosed as having nonarrhythmic syncope by loop recording showed that none of these patients died suddenly. Cardiac loop ECG recording is an important new diagnostic test in patients with syncope unexplained by Holter monitoring.     

Utility of cardiac event recorders in diagnosing arrhythmic etiology of palpitations in patients without structural heart disease

OBJECTIVE: To determine the diagnostic yield of transtelephonic event monitors for identifying the reason for palpitations in patients with no structural heart disease. PATIENTS AND METHOD: For 20 months we enrolled all patients reporting palpitations in whom heart disease had been ruled out by medical history, physical examination, ECG and transthoracic echocardiography. All patients underwent 24 h Holter monitoring, which did not provide diagnostic information. Later, a Cardiotest 4DM transtelephonic event monitor was provided to each patient for a mean of 15 3 days. We used SPSS V 10 for statistical analysis. RESULTS: Two hundred twenty-seven consecutive patients were enrolled. Mean age was 45 3 years (range 12-85); 167 were females (74%). Two hundred twelve of the 227 patients (93.3%) experienced palpitations while wearing the device, and 210 (92.5%) used the monitor correctly, recording the cardiac rhythm during palpitations. Fifteen patients (6.6%) had no palpitations during the days of study. In 125 (55%) the Cardiotest 4DM correctly recorded and transmitted arrhythmia that justified the patients' reference to palpitations. In 35 (15.4%) significant arrhythmia was detected: paroxysmal supraventricular tachycardia in 21, atrial fibrillation in 9, atrial flutter in 5, runs of ventricular extrasystoles in 4 and right outflow tract ventricular tachycardia in 1. Sinus rhythm was recorded during palpitations in 85 patients (37%), and arrhythmia as the cause could be ruled out. CONCLUSIONS: Cardiotest 4DM identifies arrhythmia in a very high proportion of patients with palpitations and no structural heart disease.     

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 patient-triggered 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.     

Recurrent unexplained palpitations (RUP) study comparison of implantable loop recorder versus conventional diagnostic strategy.

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 (< or =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 (euro 3,056 +/- euro 363 vs. euro 6,768 +/- euro 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.     

Ambulatory Holter electrocardiography: choice of technologies and clinical uses

Rapid growth in the use and complexity of Holter monitoring technologies has resulted in the diverse recorders and analysis devices that are compared in this review. Holter recording modes include continuous recording, which makes all electrocardiographic (ECG) data available for analysis; patient-activated recording, which is useful for capturing infrequent symptomatic arrhythmias; and event recording, which provides data on ECG events detected by the recorder, but whose reliability is limited. Various sophisticated, computer-based analysis systems exist, with varying prices and degrees of accuracy and reliability. Quantitative data are essential in the use of Holter monitoring to define the response of ventricular arrhythmias to therapeutic interventions, but the physician must be wary of quantitative data unless a quality-control program has been established and validated. Although Holter monitoring is safe, problems in recording and in differentiating artifacts from true cardiac rhythm disturbances may result in false clinical diagnoses unless these problems are recognized.     

Supraventricular Arrhythmia Following Patent Foramen Ovale Percutaneous Closure

BackgroundRandomized studies have reported low rates of atrial fibrillation (AF) after patent foramen ovale (PFO) closure (<6%) but have relied on patient-reported symptomatic episodes, so the true incidence and timing of AF after PFO closure remain unknown.ObjectivesThe aim of this study was to prospectively determine the incidence, timing, and determinants of supraventricular arrhythmia following PFO closure on the basis of loop recorder monitoring.MethodsCardiac monitoring was proposed to all patients after PFO closure from June 2018 to October 2021 at a single center by means of implantable loop recorder monitoring in patients considered at higher risk for AF (age ≥ 55 years, associated cardiovascular risk factors, prior palpitations, or documented supraventricular ectopic activity) or 4-week external loop recorder monitoring in other patients. The primary endpoint was the incidence of AF, atrial flutter, or supraventricular tachycardia lasting >30 seconds within 28 days of the procedure. Determinants of the primary endpoint were assessed using a stepwise logistic regression model.ResultsA total of 225 patients were included. The primary endpoint occurred in 47 patients (20.9%), including 13 (9.9%) and 24 (28.9%) among patients monitored with external loop recorders and implantable loop recorders, respectively. Overall, the median delay from procedure to arrhythmia was 14.0 days (IQR: 6.5-19.0 days), and one-half of these patients reported symptomatic episodes. Determinants of the primary endpoint were older age (adjusted OR: 1.67 per 10-year increase; 95% CI: 1.18-2.36), device left disc diameter ≥25 mm (adjusted OR: 2.67; 95% CI: 1.19-5.98) and male sex (adjusted OR: 4.78; 95% CI: 1.96-11.66).ConclusionsUsing loop recorder monitoring for ≥28 days, supraventricular arrhythmia was diagnosed in 1 in 5 patients, with a median delay of 14 days, suggesting that this postprocedural event has so far been underestimated.     

Syncope: Review of Monitoring Modalities

Elucidating the underlying cause of unexplained syncope, palpitations or other possible arrhythmia-related symptoms is a formidable clinical challenge. Cardiac monitoring supplements the most important “test” in patients with syncope or palpitations, that of a thoughtful history and physical examination. Ideally, comprehensive physiologic monitoring during spontaneous symptoms would constitute what, at present, is an unattainable gold standard test for establishing a cause. Short of that goal, establishing an accurate symptom-rhythm correlation can often provide a diagnosis. Ambulatory outpatient monitoring is a powerful diagnostic tool for the evaluation of cardiac arrhythmias. Evolving technologies have provided a vast array of monitoring options for patients suspected of having cardiac arrhythmias, with each modality differing in duration of monitoring, quality of recording, convenience and invasiveness. Holter monitors, event monitors and external loop recorders are non-invasive and provide easily accessible short-term monitoring solutions. In instances where the diagnosis remains elusive, a more long-term strategy with an implantable loop recorder may be the preferred path.     

Usefulness of the implantable subcutaneous recorder in the diagnosis of recurrent syncope of unknown etiology in patients without structural heart disease and negative tilt test and electrophysiological study

BACKGROUND AND OBJECTIVES: In up to 38% of the cases, the etiology of syncope difficult to determine. The main obstacle for diagnosis of the causes of syncope lies in the unpredictable frequency of episodes. Development of implantable loop recorders allows long term electrocardiographic monitoring. The aim of this study was to evaluate the usefulness of the implantable loop recorder for the diagnosis of recurrent syncope of unknown origin. PATIENTS AND METHODS: From May 1991 to April 1999, a cohort of 176 patients with recurrent syncope was prospectively assessed. Investigations, including Holter monitoring, Tilt Test and electrophysiological study, allowed the determination of the etiology in 161 patients. The remaining 15 patients, without structural cardiac disease were selected for continuous electrocardiographic monitoring using an implantable loop recorder. RESULTS: During follow up after implant, 15 +/- 2 months (X- +/- SEM), 9 patients showed recurrence of symptoms concordant with prior episodes (time: 105 +/- 30 days). In 7 cases records during symptoms were diagnostic (0.47; CI 95%: 0.21-0.73), in 3 cases a diagnosis with documented arrhythmia was achieved, and in 4 other cases a presumptive clinical diagnosis of non-arrhythmic cause was made. In 8 patients, 6 with no recurrences, diagnosis was not possible. There were no complications related to the use of the device. CONCLUSIONS: The strategy of long term monitoring with the implantable loop recorder is safe and effective in patients with recurrent syncope of unknown etiology.     

Evaluation of Outpatient Arrhythmias and Pacemakers Utilizing Transtelephonic Monitoring Devices

Background: The purpose of this trial was to evaluate a patient actuated transtelephonic cardiac monitoring system in order to document cardiac arrhythmias and cardiac pacemaker function. Material: Eighty-two patients were prospectively evaluated, 69 with pacemaker (group I) and 13 with symptomatic arrhythmias (group II). Two different recorders were used: a memory loop-recorder (KH) and a wrist-worn recorder (HW). Both of them were implemented using a small, portable, battery-powered transmitter, which monitors a modified V5 in KH and a lead 1 with the HW over regular nondigital pulse telephone lines. Results: In group I, 54 patients used single chamber pacemakers, 2 VDDR, and 13 used dual chamber devices. In group II, all patients included referred palpitations as their symptom. In group I, 248 registers were made using the KH and 50 with the HW. Recordings were made with KH had a 96% accuracy in the diagnosis of the ECG, while HW recordings failed to detect the QRS and the spike in 52% of the cases. Arrhythmia patients (group II) made 65 recordings with KH, all symptomatic: 28 were ventricular ectopic beats (23 isolated, 4 bigeminy, and 1 coupled ventricular ectopic beats); 9 supraventricular ectopic beats (isolated); 18 episodes of sinus tachycardia; and 10 normal sinus rhythm. Artifact was present partially in 6 other recordings, but did not affect the diagnosis. Two patients made no recordings and were excluded from the trial (group I). Conclusions: The loop-recording transtelephonic monitoring system is an excellent tool for the evaluation of patients with symptomatic arrhythmias and pacemaker. The memory KH had an excellent performance, even over regular telephone lines. The accuracy of the HW recordings was low and failed to evaluate the QRS, probably due to the direction of the AQRS vector.     

Validation of trend-supported ST segment analysis of long-term ECG recordings

Trend recordings of relative ST-segment deviations represent a useful tool for the identification of ischemia-like episodes during Holter monitoring. For the generation of trend recordings beat-to-beat data are filtered. The influence of the time constant of the filter on the sensitivity and the specificity for the detection of ischemia-like ECG changes is unknown, however. Ischemia-like episodes were, therefore, simulated and recorded by a frequency modulated Holter recorder and by a conventional six-channel ECG system. Relative ST-segment deviations were filtered using a time constant of 8, 16, 32 or 64 s, or an arithmetic averaging over 9 s for the generation of ST-segment trends. The magnitude of short-lasting ST-segment deviations was underestimated, when beat-to-beat data were filtered using time constants of greater than or equal to 32 s. The influence of posture-related ECG changes on the ST-segment trends was investigated by recording lead CM5 in 14 consecutive patients in different positions by a conventional ECG system. Four out of the 14 patients developed ST-segment elevations greater than or equal to 0.1 mV during leftsided position. Only in these four patients were ST-segment deviations of similar magnitude recorded during the following Holter monitoring. The posture-related ST-segment changes were characterized by an abrupt onset and an abrupt end, resulting in a box-like shape which enabled their correct identification in the ST-segment trend analysis. In order to determine the relative frequency of posture-related ST-segment changes, 35 patients with coronary artery disease (CAD) and 35 patients without underwent Holter monitoring.(ABSTRACT TRUNCATED AT 250 WORDS)     

Novel use of an "insertable" loop recorder

A patient with palpitations and suspected arrhythmia underwent Holter and external loop recorder monitoring. No arrhythmias were detected by these traditional monitoring methods. An insertable loop recorder (ILR) was placed on the patient's chest and used as an extended loop recorder. An arrhythmia was ultimately recorded by the externally placed ILR leading to appropriate treatment.     

Event recorder for etiological evaluation of sporadically occurring cardiovascular complaints and symptoms

Rarely and transient occurring arrhythmia, palpitation, dizziness, syncopes and chest pain frequently cause symptoms and complaints to patients with congenital cardiac defects. The reliable identification of their pathogenesis is often difficult. The study presented here demonstrates the impact of an event recorder for enlightening sporadically occurring complaints and symptoms. Fifty patients (age between 11 and 70 years, median 27 years) were examined with an event recorder (King of Hearts Express, Instromedix, Hillsboro, USA). The patients were referred to an outpatient clinic for congenital cardiac defects in order to clarify unexplained arrhythmia, palpitations, dizziness, or syncope. Included were patients above 10 years of age. Previous cardiac studies (including ECG, exercise-ECG, Holter-Monitoring) were non-diagnostic in all. Altogether 227 ECGs had been recorded. 95% of them were of diagnostic quality. The event recorder afforded ambulatory monitoring and the median duration of monitoring was 22.5 days. The average number of registered events was 4.5 +/- 3.8. In 24% of the patients (n = 12) diagnostic and/or therapeutical consequences resulted: electrophysiological examination (n = 5), drug treatment (n = 4) and pacemaker implantation (n = 3). The event recorder is an important and highly effective tool in diagnosing sporadical transient symptoms and complaints, especially arrhythmias.     

Novel use of an “insertable” loop recorder

A patient with palpitations and suspected arrhythmia underwent Holter and external loop recorder monitoring. No arrhythmias were detected by these traditional monitoring methods. An insertable loop recorder (ILR) was placed on the patient’s chest and used as an extended loop recorder. An arrhythmia was ultimately recorded by the externally placed ILR leading to appropriate treatment.     

Suspected cardiac syncope in elderly patients: use of the 12-lead electrocardiogram to select patients for holter monitoring.

BACKGROUND: Results of 24-hour Holter monitoring in elderly patients are often unhelpful, since the prevalence of asymptomatic arrhythmias increases and their prognostic significance is unclear. We investigated the value of the resting electrocardiogram (ECG) in predicting significant findings on 24-hour Holter recordings in those suspected of having cardiac syncope. OBJECTIVE: To see whether the resting 12-lead ECG can be used as a screening tool to select elderly patients suspected of having cardiac syncope for 24-hour ECG monitoring. METHOD: Comparison of resting 12-lead ECGs and 24-hour Holter tapes in 145 consecutive elderly outpatients suspected of having a cardiac cause for falls, dizziness, or syncope. RESULTS: Four of 30 normal ECGs (13%) showed an abnormality on Holter monitoring as compared with 55 of the 115 abnormal ECGs (47.8%; chi = 11.7143, p < 0.005). In the 'normal' group the 4 abnormal Holter recordings all showed short runs of supraventricular tachycardia, and no intervention resulted. The 115 abnormal resting ECGs showed either ischaemia (n = 27), dysrhythmia (n = 28), sinus bradycardia (n = 22), or conduction defects (n = 38). The 55 of these which showed abnormalities on Holter recordings occurred mostly where the resting ECG showed dysrhythmia (n = 14/28; 50%), bradycardia (n = 19/22; 86.4%), and conduction defect (n = 17/38; 44.7%). Seven patients had complete heart block on Holter, and all had conduction defects on resting ECG (p < 0.0004). Fifteen patients had pauses of longer than 3 s on Holter; all had conduction defect, bradycardia, or dysrhythmias on resting ECG (p < 0.0045). Sixteen patients were paced because of complete heart block or pauses on Holter recordings, and all had either bradycardia or conduction defects on resting ECG, resulting in complete resolution of their symptoms. CONCLUSIONS: Patients with suspected cardiac syncope and normal resting ECGs are unlikely to reveal significant abnormalities on single 24-hour Holter monitoring. Cardiac event recorder or prolonged Holter monitoring may be required in patients with strong clinical history. Those with abnormal ECGs, in particular sinus bradycardia and conduction defects, are highly likely to have significant abnormalities on 24-hour ECG monitoring.