Detection and Predictors of Paroxysmal Atrial Fibrillation in Acute Ischemic Stroke and Transient Ischemic Attack Patients in Singapore

A Simplified Risk Score to Predict In-Hospital Newly-Diagnosed Atrial Fibrillation in Acute Ischemic Stroke Patients

Purpose

Atrial fibrillation (AF) is a significant cause of stroke, and newly diagnosed AF (NDAF) is typically detected in the early period of stroke onset. We aimed to identify the factors associated with in-hospital NDAF in acute ischemic stroke patients and developed a simplified clinical prediction model.

Methods

Patients with cryptogenic stroke aged 18 years or older who were admitted between January 2017 and December 2021 were recruited. NDAF was determined by inpatient cardiac telemetry. Univariable and multivariable regression analyses were used to evaluate the factors associated with in-hospital NDAF. The predictive model was developed using regression coefficients.

Results

The study enrolled 244 eligible participants, of which 52 NDAFs were documented (21.31%), and the median time to detection was two days (1-3.5). After multivariable regression analysis, parameters significantly associated with in-hospital NDAF were elderly (>75 years) (adjusted Odds ratio, 2.99; 95% confident interval, 1.51-5.91; P = 0.002), female sex (2.08; 1.04-4.14; P = 0.04), higher admission national institute of health stroke scale (1.04; 1.00-1.09; P = 0.05), and presence of hyperdense middle cerebral artery sign (2.33; 1.13-4.79; P = 0.02). The area under the receiver operating characteristic curve resulted in 0.74 (95% CI 0.65-0.80), and the cut-point of 2 showed 87% sensitivity and 42% specificity.

Conclusion

The validated and simplified risk scores for predicting in-hospital NDAF primarily rely on simplified parameters and high sensitivity. It might be used as a screening tool for in-hospital NDAF in stroke patients who initially presumed cryptogenic stroke.

Evaluation of the Feasibility and Efficacy of a Novel Device for Screening Silent Atrial Fibrillation (MYBEAT Trial)

BACKGROUND

myBeat is a novel cutaneous patch device that continuously records electrocardiography and automatically detects atrial fibrillation (AF) by using a new algorithm based on RR intervals. We aimed to test the diagnostic ability of this novel device for screening silent AF in asymptomatic patients.Methods and Results:A multicenter randomized prospective clinical study was performed. To be eligible for inclusion in the study, patients had to be ≥65 years of age and have ≥1 of the following risk factors: hypertension, diabetes, heart failure, ischemic heart disease, stroke, and transient ischemic attack. Patients with prior AF, an implantable pacemaker, and previous palpitation or syncope were excluded. The 300 participants were divided into 2 groups, those using myBeat (n=150) or those undergoing 24-h Holter monitoring (control group; n=150), for AF screening. The rate of AF detection was significantly higher in the myBeat than control group (16 [10.7%] vs. 7 [4.7%], respectively; P=0.04). Multivariable logistic regression analysis revealed that prior heart failure was an independent predictor of silent AF (odds ratio 12.07; 95% confidence interval 1.67-86.27; P=0.01). A 7.7-fold difference in silent AF was found between subjects with CHA₂DS₂-VASc scores of 1 point and those with scores ≥4 points.

CONCLUSIONS

The novel patch device using an original algorithm was beneficial for screening of silent AF.

High Incidence of Occult Atrial Fibrillation in Asian Patients with Cryptogenic Stroke

BACKGROUND

Occult atrial fibrillation (AF) is not uncommon in patients with stroke. In western cohorts, insertable loop recorders (ILRs) have been shown to be the gold-standard and are cost-effective for AF detection. Anticoagulation for secondary stroke prevention is indicated if AF is detected. The incidence of occult AF among Asian patients with cryptogenic stroke is unclear.

METHODS

Patients with cryptogenic stroke referred between August 2014 and February 2017 had ILRs implanted. Episodes of AF >2 minutes duration were recorded using proprietary algorithms within the ILRs, whereupon clinicians and patients were alerted via remote monitoring. All AF episodes were adjudicated using recorded electrograms. Once AF was detected, patients were counseled for anticoagulation.

RESULTS

Seventy-one patients with cryptogenic stroke, (age 61.9 ± 13.5 years, 77.5% male, mean CHA₂DS₂VASc score of 4.2 ± 1.3) had ILRs implanted. Time from stroke to the ILR implant was a median of 66 days. Duration of ILR monitoring was 345 ± 229 days. The primary endpoint of AF detection at 6 months was 12.9%; and at 12 months it was 15.2%. Median time to detection of AF was 50 days. The AF episodes were all asymptomatic and lasted a mean of 77 minutes (± 118.9). Anticoagulation was initiated in all but 1 patient found to have AF.

CONCLUSIONS

The incidence of occult AF is high in Asian patients with cryptogenic stroke and comparable to western cohorts. The combination of ILR and remote monitoring is a highly automated, technologically driven, and clinically effective technique to screen for AF.

The complexity of atrial fibrillation newly diagnosed after ischemic stroke and transient ischemic attack: advances and uncertainties

Purpose of review

Atrial fibrillation is being increasingly diagnosed after ischemic stroke and transient ischemic attack (TIA). Patient characteristics, frequency and duration of paroxysms, and the risk of recurrent ischemic stroke associated with atrial fibrillation detected after stroke and TIA (AFDAS) may differ from atrial fibrillation already known before stroke occurrence. We aim to summarize major recent advances in the field, in the context of prior evidence, and to identify areas of uncertainty to be addressed in future research.

Recent findings

Half of all atrial fibrillations in ischemic stroke and TIA patients are AFDAS, and most of them are asymptomatic. Over 50% of AFDAS paroxysms last less than 30 s. The rapid initiation of cardiac monitoring and its duration are crucial for its timely and effective detection. AFDAS comprises a heterogeneous mix of atrial fibrillation, possibly including cardiogenic and neurogenic types, and a mix of both. Over 25 single markers and at least 10 scores have been proposed as predictors of AFDAS. However, there are considerable inconsistencies across studies. The role of AFDAS burden and its associated risk of stroke recurrence have not yet been investigated.

Summary

AFDAS may differ from atrial fibrillation known before stroke in several clinical dimensions, which are important for optimal patient care strategies. Many questions remain unanswered. Neurogenic and cardiogenic AFDAS need to be characterized, as it may be possible to avoid some neurogenic cases by initiating timely preventive treatments. AFDAS burden may differ in ischemic stroke and TIA patients, with distinctive diagnostic and treatment implications. The prognosis of AFDAS and its risk of recurrent stroke are still unknown; therefore, it is uncertain whether AFDAS patients should be treated with oral anticoagulants.

Neuro-otology- some recent clinical advances

Vestibular disorders manifesting as vertigo, chronic dizziness and imbalance are common problems in neurological practice. Here, we review some recent interesting and important advances in diagnosis of vestibular disorders using the video head impulse test and in the management of benign positional vertigo and migrainous vertigo.

Optimal Duration of Monitoring for Atrial Fibrillation in Cryptogenic Stroke: A Nonsystematic Review

Atrial fibrillation (AF) is the most common form of cardiac arrhythmias and an independent risk factor for stroke. Despite major advances in monitoring strategies, clinicians tend to miss the diagnoses of AF and especially paroxysmal AF due mainly to its asymptomatic presentation and the rather limited duration dedicated for monitoring for AF after a stroke, which is 24 hours as per the current recommended guidelines. Hence, determining the optimal duration of monitoring for paroxysmal atrial fibrillation after acute ischemic stroke remains a matter of debate. Multiple trials were published in regard to this matter using both invasive and noninvasive monitoring strategies for different monitoring periods. The data provided by these trials showcase strong evidence suggesting a longer monitoring strategy beyond 24 hours is associated with higher detection rates of AF, with the higher percentage of patients detected consequently receiving proper secondary stroke prevention with anticoagulation and thus justifying the cost-effectiveness of such measures. Overall, we thus conclude that increasing the monitoring duration for AF after a cryptogenic stroke to at least 72 hours will indeed enhance the detection rates, but the cost-effectiveness of this monitoring strategy compared to longer monitoring durations is yet to be established.