New-onset atrial fibrillation (AF) is a new or first detectable episode of a chaotic and irregular atrial arrhythmia. Prevalence increases progressively with age.
Causes significant morbidity and mortality including palpitations, dyspnea, angina, dizziness or syncope, and features of congestive heart failure, tachycardia-induced cardiomyopathy, stroke, and death.
ECG shows absent P waves, presence of fibrillatory waves, and irregularly irregular QRS complexes.
Most patients presenting with new-onset or “acute” atrial fibrillation (AF) do not require immediate cardioversion. Most patients will require medical therapy to control ventricular rate.
Patients who develop hemodynamic compromise should have immediate direct current cardioversion.
If the precise timing of the onset of AF is unclear, a transesophageal echocardiogram must be performed to exclude left atrial clots before cardioversion.
Atrial fibrillation (AF) is a supraventricular tachyarrhythmia. It is characterized by uncoordinated atrial activity on the surface ECG, with fibrillatory waves of varying shapes, amplitudes, and timing associated with an irregularly irregular ventricular response when atrioventricular conduction is intact. New-onset AF is defined as a new onset or a first detectable episode of AF, whether symptomatic or not.
This topic will concentrate on new-onset AF in the nonvalvular and nonsurgical settings.
History and exam
Key diagnostic factors
- irregular pulse rate
Other diagnostic factors
- elevated jugular venous pressure
- added heart sounds
- evidence of stroke
- increasing age
- diabetes mellitus
- congestive heart failure
- valvular heart disease
- coronary artery disease (CAD)
- other atrial arrhythmias
- cardiac or thoracic surgery
- hypoxic pulmonary conditions
- alcohol intoxication
- inflammatory disorders
- excessive exercise
1st investigations to order
- serum electrolytes
- cardiac biomarkers
- thyroid function tests
- transthoracic echocardiogram
- transesophageal echocardiogram (TEE)
Investigations to consider
- electrophysiologic study
- exercise stress tests
hemodynamically stable with left atrial thrombus
hemodynamically stable without left atrial thrombus: symptom onset <48 hours
hemodynamically stable without left atrial thrombus: symptom onset ≥48 hours
hemodynamically stable without left atrial thrombus: asymptomatic
- Atrial flutter
- Wolff-Parkinson-White syndrome
- Atrial tachycardia
- 2020 ESC Guidelines for the diagnosis and management of atrial fibrillation developed in collaboration with the European Association of Cardio-Thoracic Surgery (EACTS)
- 2019 AHA/ACC/HRS focused update of the 2014 AHA/ACC/HRS guideline for the management of patients with atrial fibrillation
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