Abstract 15360: Prolonged P Wave Duration is Not Associated With New Onset Atrial Fibrillation During 10-year Follow-up After First-ever Ischemic Stroke in Lund Stroke Register

Abstract

Introduction: Prolonged P-wave duration (PWD) is associated with paroxysmal atrial fibrillation (AF), which might be underdiagnosed in ischemic stroke patients, in whom it might be pivotal for initiation of secondary prevention oral anticoagulation therapy. We aimed to assess whether PWD predicts new-onset AF during 10-year follow-up in ischemic stroke patients compared to control subjects enrolled in the Lund Stroke Register (LSR). Methods: Study sample comprised of 227 first-ever ischemic stroke patients without AF (mean age 72±12 y, 92 female) and 1:1 age- and gender- matched control subjects without stroke and AF enrolled in LSR from Mar 2001 to Feb 2002. The date of new-onset AF during follow-up was assessed by the date of first AF ECG in the regional ECG database and by record linkage with the Swedish National Patient Register. The available standard snapshot 12-lead sinus rhythm ECGs at baseline were retrieved from electronic database and digitally processed. Results: Patients with ischemic stroke compared to controls more often had hypertension (57% vs 31%), diabetes (15% vs 7%) and vascular diseases (42% vs 13%, all p < 0.005). New-onset AF was detected in 39 (17%) stroke patients and in 30 (13%) controls, p=0.296. In the multivariate Cox regression analysis, new onset AF in the stroke group was associated with age>65 years (HR=3.78, 95%CI 1.32-10.85, p=0.013) and hypertension (HR=2.42, 95%CI 1.09-5.40, p=0.030), but not with PWD. On the contrary, PWD>120 ms was the only independent predictor of new onset AF in the control group after adjustment for age and cardiovascular risk factors (HR=3.36, 95%CI 1.41-8.01, p=0.006, Figure 1). Conclusions: Prolonged P-wave duration is the strongest predictor of AF incidence during 10-year follow-up in stroke-free population. However, in ischemic stroke patients the developing of AF is more likely associated with more advanced cardiovascular comorbidities than with electrical abnormalities in the heart.