Atrial Fibrillation Risk Assessment after Embolic Stroke of Undetermined Source.

OBJECTIVE: Approximately 20% of strokes are embolic strokes of undetermined source (ESUS). Undetected atrial fibrillation (AF) remains an important cause. Yet, oral anticoagulation in unselected ESUS patients failed in secondary stroke prevention. Guidance on effective AF detection is lacking. Here, we introduce a novel, non-invasive AF risk assessment after ESUS. METHODS: Catch-Up ESUS is an investigator-initiated, observational cohort study conducted between 2018 and 2019 at the Munich University Hospital. Besides clinical characteristics, patients received ≥72 h digital electrocardiogram recordings to generate the rhythm irregularity burden. Uni- and multivariable regression models predicted the primary endpoint of incident AF, ascertained by standardized follow-up including implantable cardiac monitors. Predictors included the novel rhythm irregularity burden constructed from digital electrocardiogram recordings. We independently validated our model in ESUS patients from the University Hospital Tübingen, Germany. RESULTS: A total of 297 ESUS patients were followed for 15.6 ± 7.6 months. Incident AF (46 patients, 15.4%) occurred after a median of 105 days (25th to 75th percentile 31-33 days). Secondary outcomes were recurrent stroke in 7.7% and death in 6.1%. Multivariable-adjusted analyses identified the rhythm irregularity burden as the strongest AF-predictor (hazard ratio 3.12, 95% confidence interval 1.62-5.80, p < 0001) while accounting for the known risk factors age, CHA2 DS2 -VASc-Score, and NT-proBNP. Independent validation confirmed the rhythm irregularity burden as the most significant AF-predictor (hazard ratio 2.20, 95% confidence interval 1.45-3.33, p < 0001). INTERPRETATION: The novel, non-invasive, electrocardiogram-based rhythm irregularity burden may help adjudicating AF risk after ESUS, and subsequently guide AF-detection after ESUS. Clinical trials need to clarify if high-AF risk patients benefit from tailored secondary stroke prevention. ANN NEUROL 2023;93:479-488.

Detection of Atrial Fibrillation on Stroke Units: Comparison of Manual versus Automatic Analysis of Continuous Telemetry.

BACKGROUND: Detection of atrial fibrillation (AF) is one of the primary diagnostic goals for patients on a stroke unit. Physician-based manual analysis of continuous ECG monitoring is regarded as the gold standard for AF detection but requires considerable resources. Recently, automated computer-based analysis of RR intervals was established to simplify AF detection. The present prospective study analyzes both methods head to head regarding AF detection specificity, sensitivity, and overall effectiveness. METHODS: Consecutive stroke patients without history of AF or proof of AF in the admission ECG were enrolled over the period of 7 months. All patients received continuous ECG telemetry during the complete stay on the stroke unit. All ECGs underwent automated analysis by a commercially available program. Blinded to these results, all ECG tracings were also assessed manually. Sensitivity, specificity, time consumption, costs per day, and cost-effectiveness were compared. RESULTS: 216 consecutive patients were enrolled (70.7 ± 14.1 years, 56% male) and 555 analysis days compared. AF was detected by manual ECG analysis on 37 days (6.7%) and automatically on 57 days (10.3%). Specificity of the automated algorithm was 94.6% and sensitivity 78.4% (28 [5.0%] false positive and 8 [1.4%] false negative). Patients with AF were older and had more often arterial hypertension, higher NIHSS at admission, more often left atrial dilatation, and a higher CHA2DS2-VASc score. Automation significantly reduced human resources but was more expensive compared to manual analysis alone. CONCLUSION: Automatic AF detection is highly specific, but sensitivity is relatively low. Results of this study suggest that automated computer-based AF detection should be rather complementary to manual ECG analysis than replacing it.

Functional long-term outcome following endovascular thrombectomy in patients with acute ischemic stroke.

Endovascular thrombectomy (EVT) is the most effective treatment for acute ischemic stroke caused by large vessel occlusion (LVO). Yet, long-term outcome (LTO) and health-related quality of life (HRQoL) in these patients have rarely been addressed, as opposed to modified Rankin scale (mRS) recordings. We analysed demographic data, treatment and neuroimaging parameters in 694 consecutive stroke patients in a maximum care hospital. In 138 of these patients with respect on receipt of written informed consent, LTO and HRQoL were collected over a period of 48 months after EVT using a standardised telephone survey (median 2.1 years after EVT). Age < 70 years (OR 4.82), lower NIHSS on admission (OR 1.11), NIHSS ≤ 10 after 24 h (OR 11.23) and complete recanalisation (mTICI3) (OR 7.79) were identified as independent predictors of favourable LTO. Occurrence of an infection requiring treatment within the first 72 h was recognised as a negative predictor for good long-term outcome (OR 0.22). Patients with mRS > 2 according to the telephone survey more often had complaints regarding mobility, self-care, and usual activity domains of the HRQoL. Our results underline a sustainable positive effect of effective EVT on the quality of life in LVO stroke. Additionally, predictive parameters of outcome were identified, that may support clinical decision making in LVO stroke.

Long-term functional outcome and quality of life 2.5 years after thrombolysis in acute ischemic stroke.

BACKGROUND: Evaluation of outcome after stroke is largely based on assessment of gross function 3 months after stroke onset using scales such as mRS. Cognitive or social functions, level of symptom burden or emotional health are not usually assessed, nor are data available on long-term functional outcomes years after stroke. METHODS: Analysis of 1141 patients with AIS treated with IVT from two major German university hospitals between 2017 and 2020. Patient characteristics and short-term outcome were analysed from patient records. Long-term outcome of 228 patients with prior written informed consent was assessed via telephone survey using mRS and PROMs (EQ-5D-5L, EQ-VAS) 2.5 years after stroke. RESULTS: Predictors of excellent to good long-term outcome were younger age, event to door time ≤ 2 h, NIHSS ≤ 6 on admission and NIHSS ≤ 6 after IVT. Stroke recurrence was a negative predictor. Predictors of excellent quality of life at 2.5 years included age < 73 years, lower NIHSS after IVT, absence of hypertension. Quality of life was rated in all dimensions with a medium score of 1 and a medium EQ-VAS of 70, representing the good general health status of this stroke population. CONCLUSION: Main predictors of an excellent to good long-term outcome and excellent QoL 2.5 years after stroke are younger age, lower NIHSS, and event to door time ≤ 2 h. Research on long-term outcome after disease and treatment is of utmost importance, as it has the ability to reveal the patient true functional outcome and quality of life and to provide information on the status of independence and self-esteem.

[Embolic stroke of undetermined source (ESUS) - Classification of a new stroke entity]. / Embolischer Schlaganfall mit ungeklärter Emboliequelle (ESUS) ­ Klassifikation einer neuen Schlaganfallentität.

Embolic stroke of undetermined source (ESUS) represents a subpopulation of cryptogenic strokes defined by its embolic stroke pattern on imaging and if after a carefully performed diagnostic evaluation, a specific, well recognized cause of stroke has not been identified. This review article analyses the basics of the ESUS concept and provides an overview of the evidence from recent cohort studies. The definition, aetiology and diagnosis of ESUS are reassessed. Targeted diagnostics in ESUS patients can reduce the number of cryptogenic strokes by making a specific diagnosis.

Atrial Fibrillation in Patients with Embolic Stroke of Undetermined Source during 3 Years of Prolonged Monitoring with an Implantable Loop Recorder.

BACKGROUND: Undocumented atrial fibrillation (AF) is suspected as a main stroke cause in patients with embolic stroke of undetermined source (ESUS), but its prevalence is largely unknown. This prospective study therefore aimed at delineating the prevalence of AF in patients with ESUS using continuous cardiac monitoring by implantable loop recorder (ILR) with daily remote interrogation over a period of 3 years and its clinical consequences, including recurrent stroke. METHODS: In consecutive patients with an ESUS diagnosis after complete work-up, an ILR was implanted and followed by daily remote monitoring until AF was detected or a follow-up of at least 3 years was completed. Additionally, the ILR was interrogated in-hospital in 6-month intervals. RESULTS: A total of 123 patients (74 male, mean age 65 ± 9 years) were enrolled and completed the 3 years study period. AF was detected in 51 patients (41.4%). In 43 of the 51 AF positive patients (84%) oral anticoagulation was established. Recurrent strokes occurred in 18 patients (14.6%) of this ESUS population, 9 of these patients being AF positive (17.6% of the AF-positive patients) and 9 being AF negative (12.5% of AF-negative patients). Patients with AF were slightly older than patients without AF (63.1 ± 8.8 vs. 67.5 ± 9.6 years, p = 0.12). Other parameters such as CHA2DS2-VASc score, infarct localization, micro- and macroangiopathy, carotid or aortic plaques, or stroke recurrence were not significantly different between groups. CONCLUSION: In ESUS patients, early implantation of an ILR with cardiac monitoring and remote transmission over a 3-year period detected AF in 41.4% and resulted in oral anticoagulation in 84% of these patients.

Detection of atrial fibrillation in patients with embolic stroke of undetermined source by prolonged monitoring with implantable loop recorders.

Recently, the clinical entity embolic stroke of undetermined source (ESUS) has been defined for patients with ischemic strokes, where neither a cardioembolic nor a non-cardiac source can be detected. These patients may suffer from asymptomatic atrial fibrillation (AF), terminating spontaneously and thus eluding detection. Implantable loop recorders (ILR) with automatic AF detection algorithms can detect short-lasting, subclinical AF. The aim of this study was to prospectively assess and predict AF detection in patients with ESUS using ILR with daily remote interrogation. Patients with acute ESUS received an ILR, were seen every 6 months and additionally interrogated their ILR daily using remote monitoring. The incidence of AF detection was assessed and parameters which might predict AF detection (clinical and from magnetic resonance tomography) were analysed. ILR implantation was performed in 123 patients on average 20 days after stroke. During a mean follow-up of 12.7±5.5 months, AF was documented and manually confirmed in 29 of 123 patients (23.6 %). First AF detection occurred on average after 3.6±3.4 months of monitoring. Patients with AF were on average older, had a higher CHA2DS2-VASc score and more often cerebral microangiopathy. In conclusion, AF can be documented in approximately 25 % of patients with the diagnosis of ESUS after careful work-up within a year of monitoring by an ILR and daily remote interrogation. This had important therapeutic consequences (initiation of anticoagulation for secondary stroke prevention) in these patients.