Prolonged QTc Interval Predicts Poststroke Paroxysmal Atrial Fibrillation

Abstract

A trial fibrillation (AF) is a strong risk factor for ischemic stroke and a leading cause of cardioembolic stroke. 1In particular, patients with AF with previous stroke are at high risk of recurrence.2 Because anticoagulant therapy can remarkably reduce the risk of recurrence, 3 early identification of AF is crucial for targeted secondary prevention.Persistent AF is usually easy to diagnose using the standard 12-lead ECG. However, paroxysmal AF (PAF) is often difficult to detect in patients with acute ischemic stroke (AIS) because such patients are frequently asymptomatic or present with sinus rhythm on ECGs, 4 because of which the prevalence of PAF is possibly underestimated and anticoagulants are underused. Repetitive and extended cardiac monitoring, including standard 12-lead ECG, 24-hour Holter ECG, and inpatient telemetry monitoring, are recommended to detect occult PAF in patients with AIS. 5 However, the optimal timing, duration, and method to detect PAF remain to be clarified, and the detection rate of PAF after stroke is limited. Therefore, it would be helpful to determine a factor predicting covert PAF in patients with sinus rhythms on ECGs.The QT interval corrected for heart rate (QTc)-which represents the ventricular action potential duration-has long been established as a predictor of cardiac morbidity and mortality. 6,7 Several large population-based studies have recently shown that a prolonged QTc interval is associated with an increased risk of AF development. [8][9][10] Moreover, small studies have suggested that patients with congenital long-QT syndrome (LQTS) have a greater risk of developing AF than the general population.11,12 Thus, we hypothesized that the QTc interval is potentially a good predictor of occult PAF in patients with AIS. In the present study, we aimed to assess the predictive value of a prolonged QTc interval for the detection of poststroke PAF, using data from our observational stroke registry system. MethodsThe ethics committee at our institution approved the protocol of this study. The Tokyo Women's Medical University Stroke Registry Retrospective Cohort is an observational study including 1038 consecutive patients with AIS hospitalized at the Department of Neurology, Tokyo Women's Medical University Hospital, between April 2003 and November 2013. After excluding 66 patients with Background and Purpose-Paroxysmal atrial fibrillation (PAF) is often difficult to detect in patients with acute ischemic stroke. We aimed to assess the predictive value of a prolonged QT interval corrected for heart rate (QTc) in PAF detection after acute ischemic stroke. Methods-We enrolled 972 patients with acute ischemic stroke consecutively extracted from our observational stroke registry system. Exclusion criteria were as follows: (1) AF on the initial 12-lead ECG (n=171); (2) previously diagnosed PAF (n=47); and (3) the use of a cardiac pacemaker (n=10). Of the 972 patients, 744 (mean age, 67.6 years; men, 62.6%) were eligible for analysis. The clinical characteristics and 12-lead ECG findin...

Prolonged corrected QT interval in predicting atrial fibrillation: A systematic review and meta‐analysis

“…The QT interval corrected for heart rate (QTc) is a simple electrocardiogram parameter as an indicator of ventricular repolarization and is widely used as a predictor of life‐threatening ventricular arrhythmias . Recent studies revealed that a prolonged QTc interval was a predictor of AF incidence . Therefore, the aim of this meta‐analysis is to investigate whether prolonged QTc would be a potent risk factor of AF and how much the efficacy of prolonged QTc predict AF.…”

Insular Cortex Lesions, Cardiac Troponin, and Detection of Previously Unknown Atrial Fibrillation in Acute Ischemic Stroke

“…8,15,16 Besides longer duration of ECG monitoring, we identified older age, history of hypertension, lesions within the insular cortex, and higher levels of circulating hs-cTnT to be associated with newly detected pAF. A regression model including these variables yielded better discriminative performance for new pAF than both the CHADS 2or CHA 2 DS 2 -VASc-score alone.…”

“…In a recent study, prolonged QTc interval was associated with detection of pAF after stroke. 16 Fifth, the presence of embolic infarct pattern was not recorded in the entire cohort. Consequently, the findings of insula cortex stroke might be biased by the embolic nature.…”

Action potential shortening rescues atrial calcium alternans

“…; Hoshino et al . ). Although the atrial and ventricular myocardium differ in their endowment with ion channels (see below), both tissues still show important commonalities, a fact that suggests that many patients with LQTS are also likely to exhibit delayed atrial repolarization (Kirchhof et al .…”