Association of Electrocardiographic P-Wave Markers and Atrial Fibrillation in Embolic Stroke of Undetermined Source.

BACKGROUND: Several P-wave indices are thought to represent underlying atrial remodeling and have been associated with ischaemic stroke even in the absence of atrial fibrillation (AF). However, the utility of these P-wave indices in predicting outcomes in patients with embolic stroke of undetermined source (ESUS) has not been studied. The aim of this study is to examine these different P-wave indices towards predicting new-onset AF and stroke recurrence in a cohort of patients with ESUS, thereby demonstrating the value of these electrocardiographic markers for stroke risk stratification. METHODS: Between October 2014 and October 2017, consecutive patients diagnosed with ESUS were followed for new-onset AF and ischaemic stroke recurrence. The various P-wave indices, namely, the P-terminal force in the precordial lead V1 (PTFV1), P-wave duration, P-wave dispersion, interatrial blocks, and P-wave axis, were assessed on the initial electrocardiogram on presentation and studied for their relation to eventual AF detection and recurrent stroke. RESULTS: 181 ischaemic stroke patients with ESUS were recruited and followed up for a median duration of 2.1 years. An abnormal PTFV1 was associated with occult AF detection but not with recurrent ischaemic strokes. No significant association was observed between the other P-wave indices with either occult AF or stroke recurrence. CONCLUSION: PTFV1 is associated with AF detection but not recurrent strokes in ESUS patients and can be a useful electrocardiographic marker for further risk stratification in ESUS patients.

Left Atrial Volume Index Predicts New-Onset Atrial Fibrillation and Stroke Recurrence in Patients with Embolic Stroke of Undetermined Source.

INTRODUCTION: It is unclear which surrogate of atrial cardiopathy best predicts the risk of developing a recurrent ischemic stroke in embolic stroke of undetermined source (ESUS). Left atrial diameter (LAD) and LAD index (LADi) are often used as markers of left atrial enlargement in current ESUS research, but left atrial volume index (LAVi) has been found to be a better predictor of cardiovascular outcomes in other patient populations. OBJECTIVE: We aim to compare the performance of LAVi, LAD, and LADi in predicting the development of new-onset atrial fibrillation (AF) and stroke recurrence in ESUS. METHODS: Between October 2014 and October 2017, consecutive patients diagnosed with ESUS were followed for new-onset AF, ischemic stroke recurrence, and a composite outcome of occult AF and stroke recurrence. LAVi and LADi were measured by transthoracic echocardiogram; "high" LAVi was defined as ≥35 mL/m2 in accordance with American Society of Echocardiography guidelines. RESULTS: 185 ischemic stroke patients with ESUS were recruited and followed for a median duration of 2.1 years. Increased LAVi was associated with new-onset AF detection (aOR 1.08; 95% CI 1.03-1.14; p = 0.003) and stroke recurrence (aOR 1.05; 95% CI 1.01-1.10; p = 0.026). Patients with "high" LAVi had a higher likelihood of developing a composite of AF detection and stroke recurrence (HR 3.45; 95% CI 1.55-7.67; p = 0.002). No significant association was observed between LADi and either occult AF or stroke recurrence. CONCLUSIONS: LAVi is associated with new-onset AF and stroke recurrence in ESUS patients and may be a better surrogate of atrial cardiopathy.