Subclinical atrial fibrillation in patients with recent transient ischemic attack

J Cardiovasc Electrophysiol. 2018 May;29(5):707-714. doi: 10.1111/jce.13470. Epub 2018 Mar 22.

Abstract

Background: Atrial fibrillation (AF) is a major risk factor of stroke, but the association between AF and transient ischemic attack (TIA) is less clear. Despite this, patients with TIA are included in stroke trials.

Aims: To determine the 1-year incidence of AF in TIA patients using an insertable cardiac monitor (ICM); second, to determine factors associated with incident AF in these patients.

Methods: Prospective cohort study of patients with TIA with normal standard electrocardiogram (ECG) and 72-hour Holter monitoring (HM). Exclusion criteria were as follows: age < 18 or > 81 years; prior AF/stroke; ongoing oral anticoagulation therapy or contraindication for it; significant carotid artery stenosis; uncertain TIA diagnosis. Eligible patients received an ICM and were followed for 12 months.

Results: From November 2013 to October 2015, 809 patients were diagnosed with TIA. In total, 235 patients were eligible. Nine (3.8%) of these had AF on standard ECG or HM. Of the remaining patients, 121 refused ICM implantation. In total, 105 patients (median age 65.4 years [range 27.1-80.8], 46% males) received an ICM, which revealed AF in 7 (6.7%). Factors associated with new-onset AF were a history of recurrent TIA (odds ratio [OR] 11.5, 95% confidence interval [CI] 2.1-63.6) and heart failure (OR 12.7, 95% CI 1.71-96.83).

Conclusions: The 1-year incidence of AF in TIA patients with normal ECG and HM was 6.7% using an ICM. Factors associated with development of AF were recurrent TIA and heart failure.

Keywords: atrial fibrillation; cardiac monitoring; implantable cardiac monitor; stroke; transient ischemic attack.

MeSH terms

  • Adolescent
  • Adult
  • Aged
  • Aged, 80 and over
  • Asymptomatic Diseases
  • Atrial Fibrillation / diagnosis
  • Atrial Fibrillation / epidemiology*
  • Denmark / epidemiology
  • Electrocardiography, Ambulatory
  • Female
  • Heart Failure / epidemiology
  • Humans
  • Incidence
  • Ischemic Attack, Transient / diagnostic imaging
  • Ischemic Attack, Transient / epidemiology*
  • Male
  • Middle Aged
  • Prospective Studies
  • Recurrence
  • Risk Factors
  • Time Factors
  • Young Adult