Automatic cardiac event recorders reveal paroxysmal atrial fibrillation after unexplained strokes or transient ischemic attacks

Cardioembolic stroke is frequent in late recurrence after transient ischemic attack

BACKGROUND

Transient ischemic attack (TIA) is often followed by a stroke episode. Differences between early and late recurrent stroke, however, have not been elucidated.

METHODS

We enrolled 133 consecutive patients with acute ischemic stroke who presented to our hospital and had previously been diagnosed with TIA. They were divided into 5 groups according to the interval between TIA and subsequent stroke: <48 hours (group 1); 48 hours to 1 week (group 2); 1 week to 1 month (group 3); 1 month to 3 months (group 4); and >3 months (group 5). Patients who underwent recurrent stroke within and after 1 week subsequent to TIA (the early and late recurrence groups, respectively) were compared with regard to clinical findings.

RESULTS

Of the 133 patients, 46 (34.6%) were in group 1, 29 (21.8%) in group 2, 23 (17.3%) in group 3, 18 (13.5%) in group 4, and 17 (12.8%) in group 5. Most of the noncardioembolic strokes were observed shortly after TIA, while the percentage of cardioembolic stroke remained high even after long post-TIA periods. The prevalence of atrial fibrillation (AF) was higher in the late recurrence group than in the early recurrence group (41.4% v 24.0%, P = .033). Among 42 patients with AF, 12 (28.6%) were newly diagnosed at the time of stroke.

CONCLUSIONS

The frequency of cardioembolic stroke did not decline as time after TIA passed. More than one quarter of AF patients had been asymptomatic before stroke, suggesting the need for repeated examinations to detect AF in patients with TIA of unknown etiology.

Cardiac workup of ischemic stroke

Stroke is the leading cause of disability in developed countries and the third cause of mortality. Up to 15-30% of ischemic strokes are caused by cardiac sources of emboli being associated with poor prognosis and high index of fatal recurrence. In order to establish an adequate preventive strategy it is crucial to identify the cause of the embolism. After a complete diagnostic workup up to 30% of strokes remain with an undetermined cause, and most of them are attributed to an embolic mechanism suggesting a cardiac origin.There is no consensus in the extent and optimal approach of cardiac workup of ischemic stroke. Clinical features along with brain imaging and the study of the cerebral vessels with ultrasonography or MRI/CT based angiography can identify other causes or lead to think about a possible cardioembolic origin.Atrial fibrillation is the most common cause of cardioembolic stroke. Identification of occult atrial fibrillation is essential. Baseline ECG, serial ECG('s), cardiac monitoring during the first 48 hours, and Holter monitoring have detection rates varying from 4 to 8% each separately. Extended cardiac monitoring with event loop recorders has shown higher rates of detection of paroxysmal atrial fibrillation.Cardiac imaging with echocardiography is necessary to identify structural sources of emboli. There is insufficient data to determine which is the optimal approach. Transthoracic echocardiography has an acceptable diagnostic yield in patients with heart disease but transesophageal echocardiography has a higher diagnostic yield and is necessary if no cardiac sources have been identified in patients with cryptogenic stroke with embolic mechanism.

Simplified electrocardiogram sampling maintains high diagnostic capability for atrial fibrillation: implications for opportunistic atrial fibrillation screening in primary care

AIMS

Atrial fibrillation (AF) is a major cause of morbidity, mortality, and health resource consumption. However, as many patients with chronic AF are asymptomatic, rapid, accurate opportunistic screening is needed in primary care to detect AF. Conventional electrocardiogram (ECG) technology is too clumsy and time consuming for mass opportunistic screening, thus technology that allows easy, rapid, yet accurate AF screening is required. To address this requirement a prototype hand-held electrode assembly was developed. We hypothesized that a 6-lead frontal-plane ECG acquired from this apparatus in a seated, clothed patient would be as accurate at detecting AF as conventional 12-lead ECG in the undressed, supine patient (the 'gold standard').

METHODS AND RESULTS

Electrocardiograms were obtained from 78 patients with AF and 79 with sinus rhythm (SR). All had a conventional 12-lead ECG, a 6-lead ECG from conventionally positioned limb electrodes, a supine 6-lead recording using the prototype recorder placed on the lower thorax/upper abdomen, and a 6-lead prototype recording in the seated patient, the latter with loosened clothing only. Electrocardiograms were randomly and blindly assessed by two cardiologists for (i) diagnosis of AF vs. SR and (ii) tracing quality (subjectively assessed as good, adequate, or bad). Compared with conventional 12-lead ECG recordings, all 'new' recording methods performed satisfactorily with sensitivities ≥90% (90-99%), specificities ≥94% (94-100%), positive predictive values ≥94% (94-100%), negative predictive values ≥90% (90-99%), and accuracies ≥93% (93-99%). Tracing quality was higher in conventional 12-lead recordings (71 and 80% were assessed as good by the two observers) compared with conventional 6-lead (57 and 59%), supine prototype (41 and 31%), and sitting prototype (39 and 19%).

CONCLUSIONS

Despite inferior electrocardiographic quality a 6-lead frontal plane ECG acquired by a simple prototype hand-held electrode assembly allowed reliable differentiation of AF from SR compared with standard 12-lead ECG.

Young women have poorer outcomes than men after stroke

BACKGROUND AND PURPOSE

Gender differences in stroke outcome have not been fully assessed in young patients.

METHODS

We conducted an observational study of consecutive young ischemic stroke patients (≤ 50 years of age) admitted to a stroke unit (January 1999 to December 2009). Basal data, subtype of ischemic stroke, stroke severity [Canadian Neurological Scale (CNS)], length of hospital stay, inhospital complications, mortality and functional outcome at discharge [modified Rankin Scale (mRS) score] were analyzed. For stroke severity and outcome analyses, 2 age groups were established: 15-30 (very young group) and 31-50 years old (middle-aged young group).

RESULTS

A total of 310 patients were enrolled; 128 females and 182 males. The mean age was similar in women and men (41.07 ± 8.6 vs. 42.12 ± 8.2, NS). Migraine was more frequent in women, whereas arterial hypertension, hyperlipidemia, alcohol abuse, current smoking and atherothrombotic infarction were more frequent in men (p < 0.05). Females presented greater stroke severity than men [median CNS (IQR) = 8 (3.5) vs. 9 (2.5), p = 0.014] except in the very young group [median CNS (IQR) = 9 (1.8) vs. 8 (5), p = 0.022]. Female sex was a predictor of unfavorable outcomes (mRS >2) at discharge in the total sample (OR = 3.33; 95% CI = 1.41-7.84) and in the middle-aged young group (OR = 2.62; 95% CI = 1.05-6.53), adjusted by baseline data, stroke subtype, inhospital complications, length of stay and stroke severity.

CONCLUSIONS

Female gender is associated with worse outcomes in adult ischemic stroke patients up to 50 years old. However, this effect is not observed in younger patients (15-30 years).

Predictors of occult paroxysmal atrial fibrillation in cryptogenic strokes detected by long-term noninvasive cardiac monitoring

Background and Purpose. Paroxysmal Atrial fibrillation/Flutter (PAF) detection rates in cryptogenic strokes have been variable. We sought to determine the percentage of patients with cryptogenic stroke who had PAF on prolonged non-invasive cardiac monitoring. Methods and Results. Sixty-two consecutive patients with stroke and TIA in a single center with a mean age of 61 (+/− 14) years were analyzed. PAF was detected in 15 (24%) patients. Only one patient reported symptoms of shortness of breath during the episode of PAF while on monitoring, and 71 (97%) of these 73 episodes were asymptomatic. A regression analysis revealed that the presence of PVCs (ventricular premature beats) lasting more than 2 minutes (OR 6.3, 95% CI, 1.11–18.92; P = .042) and strokes (high signal on Diffusion Weighted Imaging) (OR 4.3, 95% CI, 5–36.3; P = .041) predicted PAF. Patients with multiple DWI signals were more likely than solitary signals to have PAF (OR 11.1, 95% CI, 2.5–48.5, P < .01). Conclusion. Occult PAF is common in cryptogenic strokes, and is often asymptomatic. Our data suggests that up to one in five patients with suspected cryptogenic strokes and TIAs have PAF, especially if they have PVCs and multiple high DWI signals on MRI.

Paroxysmal atrial fibrillation in cryptogenic stroke

INTRODUCTION

Paroxysmal atrial fibrillation (PAF) is perhaps the most underdiagnosed mechanism of apparent cryptogenic stroke (CS). Various studies have shown that increasing the duration of monitoring can increase the diagnosis of PAF in CS.

METHODS

We compared demographic and risk factors for ischemic stroke across different TOAST (Trial of ORG 10172 in Acute Stroke Treatment) stroke subtypes to look for clinical differences between other subtypes and CS and subsequently performed periodic Holter monitoring and imaging studies in apparent CS patients.

RESULTS

Of the 298 patients with ischemic stroke, 17% had CS. Periodic holter monitoring enabled diagnosis of PAF in 29% of patients. Five of 51 patients with CS had recurrent ischemic stroke and all 5 were demonstrated as PAF on repeated Holter monitoring.

CONCLUSIONS

Long-term periodic rhythm monitoring in patients with apparent CS showed PAF in a significant percentage of CS patients, which altered subsequent treatment.

[Detection of atrial fibrillation after stroke]

Approximately every fourth stroke results from cardiac embolism. Atrial fibrillation has been recognized as a common cause for thromboembolic stroke. Detection of unknown atrial fibrillation is an important clinical challenge, as anticoagulation may effectively reduce the risk of recurrent ischemic stroke. In all patients with a cryptogenic stroke 24-h Holter monitoring should be performed in addition to a standard ECG to detect paroxysmal atrial fibrillation. In addition, it is useful to pay attention to atrial fibrillation during continuous bedside ECG monitoring on the stroke unit and in pacemaker interrogation. The indication for longer ECG monitoring by implantable loop recorders may be considered individually based on the expected probability of atrial fibrillation. The potential benefit of these devices is currently being evaluated in clinical trials.

Incidence of Atrial Fibrillation after Percutaneous Closure of Patent Foramen Ovale and Small Atrial Septal Defects in Patients Presenting with Cryptogenic Stroke

Objective

The occurrence of atrial fibrillation after percutaneous closure of a patent foramen ovale for cryptogenic stroke has been reported in a variable percentage of patients. However, its precise incidence and mechanism are presently unclear and remain to be elucidated.

Design

Prospective follow-up study.

Patients

Ninety-two patients undergoing a percutaneous patent foramen ovale closure procedure (closure group) for cryptogenic stroke were compared with a similar group of 51 patients, who were medically treated.

Methods

A systematic arrhythmia follow-up protocol to assess the incidence of AF was performed including a 7-day event-loop recording at day 1, after 6 and 12 months in patients of the closure group and compared with those of the medically treated group.

Results

The incidence of AF was similar in both study groups during a follow-up of 12 months, including 7·6% (95% CI: 3·1–15·0%) in the closure and 7·8% (95% CI: 2·18–18·9%) in the medically treated group ( P = 1·0). The presence of a large patent foramen ovale was the only significant risk factor for the occurrence of AF as demonstrated by a multivariate Cox regression analysis (95% CI, 1·275–20·018; P = 0·021).

Conclusions

Our findings indicate that patients with cryptogenic stroke and patent foramen ovale have a rather high incidence of AF during a follow-up of 12 months. Atrial fibrillation occurred with a similar frequency whether the patent foramen ovale/atrial septal defect was successfully percutaneously closed or was medically managed. The presence of a large patent foramen ovale was the only significant predictor of AF occurrence during follow-up.

[Relationship between left atrial size and paroxysmal atrial fibrillation in acute ischemic stroke]

We investigated the relationship between parosysmal atrial fibrillation (pAF) and left atrial (LA) size in patients with acute ischemic stroke. Between June 2006 and April 2008, we retrospectively enrolled 292 patients with acute ischemic stroke within 24 hours of onset, who measured LA size by transthoracic echocardiography. The patients were classified according to the presence or absence of chronic AF on admission (cAF and normal sinus rhythm (NSR) group). The NSR group was subdivided based on the pAF (pAF and non-AF group). We compared LA size among each groups. Furthermore in the NSR group, the factors associated with pAF were investigated by multivariate logistic regression analysis. Among the enrolled patients, cAF (cAF group) had 77 (26.4%), pAF (pAF group) had 32 (11.0%) and non-AF group was 183 (62.7%). The median of LA size of the cAF was highest (4.7 cm), followed by the pAF group (4.1 cm) and the non-AF group (3.5 cm) (p<0.001). Median age (72.0 for the non-AF group vs. 74.5 years for the pAF group, p<0.001), NIHSS score on admission (3.0 vs. 12.5, p<0.001), D-dimer (0.6 vs. 2.1 microg/ml, p=0.003), LA size (3.5 vs. 4.1 cm, p<0.001) were higher in the pAF group than in the non-AF group. The optimal cut-off value, sensitivity and specificity of LA size to distinguish pAF from non-AF were 3.8 cm, 68.6% and 73.8%, respectively. Multivariate logistic regression analysis demonstrated that a NIHSS score of > or =8 (odds ratio [OR], 4.399; 95% confidence interval [CI], 1.701 to 11.378, p=0.002), LA size of > or =3.8 cm (OR, 8.882; 95% CI, 3.238 to 24.268, p<0.001) and mitral valvular disease (OR, 4.677; 95% CI, 1.720 to 12.720, p=0.003) were independent factors associated with pAF. We should consider the presence of pAF when LA size is over 3.8 cm in acute ischemic stroke patients with sinus rhythm.

[Cardiologic diagnostics after stroke: what is really important?]

Patients with a stroke often exhibit similar risk factors compared to patients with coronary artery disease. The morbidity and mortality of patients surviving a stroke are strongly determined by cardiac co-morbidities. Moreover, ischemic stroke frequently results from cardiac embolism. Thus, for risk assessment and prevention of cardiovascular events patients should undergo cardiac evaluation after a stroke. Laboratory testing should include blood glucose, coagulation parameters, blood cell count and in the case of suspected acute coronary syndrome cardiac ischemic markers. Assessment of the lipid profile is useful to determine the overall cardiovascular risk. In all patients with a stroke an ECG should be recorded. In those with normal ECG and suspected thromboembolic stroke additional Holter is helpful to detect possible atrial fibrillation. Echocardiography should be performed in all patients with suspected cardioembolic stroke. Moreover, echocardiography may establish the diagnosis of structural heart disease, which has a major impact on prognosis in patients with a stroke.

Home monitoring in patients with implantable cardiac devices: is there a potential reduction of stroke risk? Results from a computer model tested through monte carlo simulations

INTRODUCTION

Patients with pacemakers and implantable defibrillators (ICD) may experience asymptomatic atrial fibrillation (AF), detected with a delay depending on the in-person follow-up schedule. Home monitoring (HM) remote control with automatic alerts for AF may drive early anticoagulation, potentially reducing stroke risk.

METHODS AND RESULTS

A sample of 136 pacemaker (103) and ICD (33) patients with or without cardiac resynchronization therapy not taking anticoagulation at implant were monitored remotely with HM. Upon HM alerts for AF, patients were recalled to update therapy. Two-year data were entered in a computer Monte Carlo model, simulating 4,000 virtual subjects with the same AF and CHADS(2) stroke risk distribution of our real population. Simulations reproduced a 2-year follow-up. Two thousand subjects were supposed to be followed with HM (HM group) and 2,000 with standard in-person follow-up (SF group) at 3, 6, 9, or 12 months. Two-year Kaplan-Meier cumulative probability of >/=24-hour AF was 15.6% (95%CI 8.5-23.3%); the AF-related symptom rate was 27% and the median CHADS(2) score was 2. As a result of simulations, stroke incidence in case of AF was 2.3 +/- 1.1% in the HM group and 2.4 +/- 1.1%, 2.5 +/- 1.2%, 2.7 +/- 1.2%, and 2.9 +/- 1.3% in the SF group with 3-, 6-, 9-, and 12-month follow-up programs, with odds ratios of 0.97 (95%CI 0.93-1.01), 0.91 (0.88-0.95), 0.87 (0.84-0.90), and 0.82 (0.79-0.85) (HM better if odds ratios <1), respectively.

CONCLUSIONS

Daily HM potentially reduces the stroke risk by 9% to 18% with respect to SF with intervisit intervals of 6 to 12 months.

Cardiac workup of ischemic stroke: can we improve our diagnostic yield?

BACKGROUND AND PURPOSE

Discovering potential cardiac sources of stroke is an important part of the urgent evaluation of the ischemic stroke patient as it often impacts treatment decisions that are essential for determining secondary stroke prevention strategies, yet the optimal approach to the cardiac workup of an ischemic stroke patient is not known.

METHODS

A review of the literature concerning the utility of cardiac rhythm monitoring (ECG, telemetry, Holter monitors, and event recorders) and structural imaging (transthoracic and transesophageal echocardiography) was performed.

RESULTS

Data supporting a definitive, optimal, and cost-effective approach are lacking, though some data suggest that appropriate patient selection can improve the diagnostic and therapeutic yield of rhythm monitoring and echocardiography in the evaluation of stroke etiology.

CONCLUSIONS

Based on available data, an algorithmic approach for the evaluation of patients with acute ischemic cerebrovascular events that takes into account therapeutic and diagnostic yield as well as cost-efficiency is proposed.

Differential use of warfarin for secondary stroke prevention in patients with various types of atrial fibrillation

Anticoagulation therapy significantly reduces the incidence of thromboembolic events in patients with atrial fibrillation (AF), and warfarin therapy at discharge is a class I-indicated drug in patients with ischemic stroke with persistent or paroxysmal AF without contraindications. The aim was to determine whether participation in the Get With The Guidelines-Stroke (GWTG-S) quality improvement program would be associated with improved adherence to anticoagulation guidelines for patients with all types of AF. Adherence to warfarin treatment at hospital discharge was assessed in eligible patients with AF who presented with stroke or transient ischemic attack, based on type of AF. Of patients with stroke, 10.5% presented with some form of AF. When AF was documented using electrocardiography or telemetry (ECG) during the present admission, eligible patients were more likely to receive warfarin compared with patients for whom AF was reported using medical history only (78.8% vs 49.4%; p<0.0001). Improvement after GWTG-S participation in warfarin use was observed in patients with ECG-documented AF (73.8% at baseline vs 88.5% after the intervention; p<0.0001), but not patients using history only. Women and elderly patients were less likely to receive warfarin, and these gaps in treatment did not narrow during the quality improvement program for patients with ECG-documented AF and those with history only. In conclusion, anticoagulation for stroke prevention was underused in general for patients with AF, even in such high-risk groups as patients with stroke. GWTG-S was associated with improved adherence for patients with ECG-documented AF, but patients with a history of AF alone were largely untreated.

Algorithm for identifying patients with paroxysmal atrial fibrillation without appearance on the ECG

Although atrial fibrillation is the most common sustained cardiac rhythm disturbance, it remains under-diagnosed. One of the most drastic complications is embolism, and strokes in particular. Patients having atrial fibrillation must be identified in order to reduce the number of strokes. The algorithm presented detects atrial fibrillation, even without it being indicated in the analyzed ECG. Based on parameters of heart rate variability, only a 60-minute single channel ECG is required. At first, all R peaks are detected and all RR intervals are calculated. After normalizing the RR intervals, the time domain parameter SDSD is calculated and the so-called Poincaré Plot is generated. The image and the time domain analysis assess a risk level, which determines whether the patient is suffering from atrial fibrillation. The resulting sensitivity calculated for ECG recordings from the MIT-BIH Atrial Fibrillation Database is 91.5% and the specificity determined for the ECG recordings from the MIT-BIH Normal Sinus Rhythm Database is 96.9%. The sensitivity depends on the atrial fibrillation burden. Even if a burden of 0 % is assumed, the results still prove satisfactory (sensitivity nearly 83%).

Noninvasive Cardiac Monitoring for Detecting Paroxysmal Atrial Fibrillation or Flutter After Acute Ischemic Stroke

Background and Purpose— Identifying paroxysmal atrial fibrillation/flutter is an essential part of the etiological workup of patients with ischemic stroke. However, there is controversy in the literature regarding the use of noninvasive cardiac rhythm monitoring with previous reviews reporting a low detection rate with routine monitoring. We performed a systematic review to determine the frequency of occult atrial fibrillation/flutter detected by noninvasive methods of continuous cardiac monitoring after acute ischemic stroke or transient ischemic attack.

Methods— Studies were identified from comprehensive searches of PubMed, EMBASE, Science Citation Index, and bibliographies of relevant articles. Only English language articles were included. Randomized controlled trials and prospective cohort studies of consecutive patients with acute ischemic stroke that fulfilled predefined criteria were eligible. Two authors conducted searches and abstracted data from eligible studies independently.

Results— Sixty studies were deemed potentially eligible. After application of eligibility criteria, 5 studies (736 participants) were included in the analysis. All studies evaluated Holter monitoring; 2 also evaluated event loop recording. In studies that evaluated Holter monitoring (588 participants), new atrial fibrillation/flutter was detected in 4.6% (95% CI: 0% to 12.7%) of consecutive patients with ischemic stroke. Duration of monitoring ranged from 24 to 72 hours. Two studies (140 participants) evaluated event loop recorders after Holter monitoring. New atrial fibrillation/flutter was detected in 5.7% and 7.7% of consecutive patients in these 2 studies.

Conclusions— Screening consecutive patients with ischemic stroke with routine Holter monitoring will identify new atrial fibrillation/flutter in approximately one in 20 patients. Although based on limited data, extended duration of monitoring may improve the detection rate. Further research is required before definitive recommendations can be made.

Holter monitoring for 24 hours in patients with thromboembolic stroke and sinus rhythm diagnosed in the emergency department

It is well known that patients with ischemic stroke show ST-T abnormalities and various rhythm abnormalities on an electrocardiogram (ECG). The most commonly encountered rhythm abnormality is atrial fibrillation. It was recently shown that paroxysmal atrial fibrillation (PAF) is an important causative factor in patients with stroke. Detection of PAF is important in identifying the cause, prognosis, and treatment in patients with thromboembolic stroke. Investigators in the present study followed patients with thromboembolic stroke who had been admitted to the emergency department in sinus rhythm; 24-h Holter monitoring was used, and patients were assessed at referral and every 6 h for 24 h with ECG, which was used to detect rhythm disturbances, especially PAF. In 26 patients with stroke who came to the emergency department, acute thromboembolic stroke was diagnosed on the basis of magnetic resonance imaging; no rhythm abnormalities were noted on Holter monitoring. Eighteen patients were male and 8 were female (mean age: 66+/-13 y). Arrhythmia was identified on ECG in 3 patients (11%) and on 24-h Holter monitoring in 24 patients (92%). PAF was diagnosed in 3 patients (11%) on ECG and in 11 patients (42%) on Holter monitoring. In 2 patients, nonsustained ventricular tachycardia was detected only on Holter monitoring, which was found to be significantly superior to ECG for the detection of arrhythmias (P<.001). Investigators found no significant relationship between PAF and variables such as hypertension, diabetes, coronary artery disease, history of myocardial infarction, ST-T changes, and elevations in cardiac markers. However, a significant relationship (P<.01) was seen between nonsustained ventricular tachycardia and a history of myocardial infarction. No relationship was discerned between arrhythmia and stroke localization. Study results suggested that (1) PAF is a commonly diagnosed rhythm abnormality, and (2) Holter monitoring is superior to routine ECG for the detection of arrhythmias such as PAF in patients anticipated to have thromboembolic stroke with sinus rhythm.

Long-term continuous external electrocardiographic recording: a review

Ambulatory electrocardiographic (AECG) monitoring is an essential tool in the diagnostic evaluation of patients with cardiac arrhythmias. Recent advances in solid-state technology have improved the quality of the ECG signals and new dedicated algorithms have expanded the clinical application of software-based AECG analysis systems. These advances, in addition to the availability of inexpensive large storage capacities, and very long-term continuous high-quality AECG monitoring, have opened new potential uses for AECG. New digital recorders have the capability of multichannel simultaneous recordings (from 3 to 12 leads) and for telemetred signal transduction. These possibilities will expand the traditional uses of AECG for arrhythmia detection, as arrhythmia monitoring to assess drug and device efficacies has been further defined by new studies. The analysis of transient ST-segment deviation still remains controversial, but considerably more data are now available, especially about the prognostic value of detecting asymptomatic ischaemia. Heart rate variability analysis has shown promise for predicting mortality rates in cardiac patients at high risk. We review recent advances in this field of non-invasive cardiac testing.

Usefulness of Ambulatory 7-Day ECG Monitoring for the Detection of Atrial Fibrillation and Flutter After Acute Stroke and Transient Ischemic Attack

BACKGROUND AND PURPOSE

Although atrial fibrillation is the most frequent cause of cardioembolic stroke, this arrhythmia remains underdiagnosed, as it is often asymptomatic or intermittent and, thus, may not be detected on standard 12-lead ECG or even 24-hour ECG recording (Holter). In this study, we hypothesized that 7-day ambulatory ECG monitoring using an event-loop recording (ELR) device would detect otherwise occult episodes atrial fibrillation and flutter (AF) after acute stroke or transient ischemic attack (TIA).

METHODS

One hundred forty-nine consecutive patients admitted to our neurology department with an acute stroke or TIA were systematically screened for emboligenic arrhythmias using standard ECG. In the absence of AF on standard ECG, patients underwent 24-hour ECG recording (Holter), which was followed by a 7-day ambulatory ECG monitoring (ELR) in patients with a normal Holter. Patients with previously documented persistent AF, with primary hemorrhagic stroke, or with acute large vessel dissection were not included in the study.

RESULTS

AF was detected in 22 patients. Standard ECG identified AF in 2.7% of the cases at admission (4/149 patients) and in 4.1% of remaining patients within 5 days (6/145). Holter disclosed AF in 5% of patients with a normal standard ECG (7/139 patients), whereas ELR detected AF in 5.7% of patients with a normal standard ECG and normal Holter (5/88 patients).

CONCLUSIONS

Following acute stroke or TIA, ELR identified patients with AF, which remained undetected with standard ECG and with Holter. ELR should, therefore, be considered in every patient in whom a cardioembolic mechanism is suspected.