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Temporal Association Between Episodes of Atrial Fibrillation and Risk of Ischemic Stroke. JAMA Cardiol 2021; 6:1364. Topic 956 Version 36.0 https://www.uptodate.com/contents/paroxysmal-atrial-fibrillation/print 14/18 7/5/23, 10:17 AM Paroxysmal atrial fibrillation - UpToDate GRAPHICS Long pause after episode of paroxysmal atrial fibrillation An example of a long postconversion pause after spontaneous conversion of an episode of paroxysmal atrial fibrillation. Graphic 132571 Version 2.0 https://www.uptodate.com/contents/paroxysmal-atrial-fibrillation/print 15/18 7/5/23, 10:17 AM Paroxysmal atrial fibrillation - UpToDate Approach to diagnosis of an irregularly irregular supraventricular rhythm* This graphic describes an approach to distinguishing atrial fibrillation (identified with a thick border) from other causes of an irregularly irregular supraventricular rhythm. While atrial fibrillation is the rhythm most commonly described as irregularly irregular, mimics of atrial fibrillation should be excluded when an irregularly irregular rhythm is identified. Of note, atrial fibrillation uncommonly occurs with a regular ventricular rhythm, as described in UpToDate content on the electrocardiogram in atrial fibrillation. ECG: electrocardiogram; AV: atrioventricular; PVCs: premature ventricular complexes; PACs: premature atrial complexes. Refer to UpToDate content on distinguishing supraventricular from ventricular rhythms. If no atrial activity is detected or the morphology of atrial activity is unclear, use ECG amplification (digital magnification or increase in gain for the entire ECG signal). https://www.uptodate.com/contents/paroxysmal-atrial-fibrillation/print 16/18 7/5/23, 10:17 AM Paroxysmal atrial fibrillation - UpToDate The ventricular rhythm associated with Mobitz I or II second-degree AV block is not irregularly irregular since there is a pattern to the variation in ventricular rate, but this pattern may not be immediately recognized. Graphic 132103 Version 1.0 https://www.uptodate.com/contents/paroxysmal-atrial-fibrillation/print 17/18 7/5/23, 10:17 AM Paroxysmal atrial fibrillation - UpToDate Contributor Disclosures David Spragg, MD, FHRS No relevant financial relationship(s) with ineligible companies to disclose. Kapil Kumar, MD No relevant financial relationship(s) with ineligible companies to disclose. Bradley P Knight, MD, FACC Grant/Research/Clinical Trial Support: Abbott [Electrophysiology]; Atricure [Electrophysiology]; Biosense Webster [Electrophysiology]; Biotronik [Electrophysiology]; Boston Scientific [Electrophysiology]; BSCI [Electrophysiology]; MDT [Electrophysiology]; Philips [Electrophysiology]. Consultant/Advisory Boards: Abbott [Electrophysiology]; Atricure [Electrophysiology]; Biosense Webster [Electrophysiology]; Biotronik [Electrophysiology]; Boston Scientific [Electrophysiology]; BSCI [Electrophysiology]; CVRx [Heart failure]; MDT [Electrophysiology]; Philips [Electrophysiology]; Sanofi [Arrhythmias]. Speaker's Bureau: Abbott [Electrophysiology]; Biosense Webster [Electrophysiology]; Biotronik [Electrophysiology]; Boston Scientific [Transeptal catheterization]; BSCI [Electrophysiology]; MDT [Electrophysiology]. All of the relevant financial relationships listed have been mitigated. Nisha Parikh, MD, MPH No relevant financial relationship(s) with ineligible companies to disclose. Contributor disclosures are reviewed for conflicts of interest by the editorial group. When found, these are addressed by vetting through a multi-level review process, and through requirements for references to be provided to support the content. Appropriately referenced content is required of all authors and must conform to UpToDate standards of evidence. Conflict of interest policy https://www.uptodate.com/contents/paroxysmal-atrial-fibrillation/print 18/18