From the Guidelines
The workup for atrial fibrillation (a-fib) should begin with a thorough history and physical examination, followed by an ECG to confirm the diagnosis, as recommended by the 2016 ESC guidelines 1. The initial evaluation of a patient with suspected or proven AF involves characterizing the pattern of the arrhythmia as paroxysmal or persistent, determining its cause, and defining associated cardiac and extracardiac factors, as outlined in the 2006 ACC/AHA/ESC guidelines 1. Key points to consider in the workup include:
- Initial testing should include a complete blood count, comprehensive metabolic panel, thyroid function tests, and a chest X-ray.
- An echocardiogram is essential to evaluate cardiac structure and function, particularly to assess for valvular disease, left atrial size, and left ventricular function, as noted in the 2001 ACC/AHA/ESC guidelines 1.
- Additional testing may include ambulatory ECG monitoring (Holter or event monitor) if the diagnosis is uncertain or to evaluate rate control.
- For patients with unexplained a-fib, consider testing for sleep apnea, alcohol or stimulant use, and other potential triggers.
- Risk stratification using the CHA₂DS₂-VASc score is crucial to guide anticoagulation decisions, with most patients with a score ≥2 for men or ≥3 for women receiving oral anticoagulation with a direct oral anticoagulant (DOAC) such as apixaban 5mg twice daily, rivaroxaban 20mg daily, or warfarin with a target INR of 2-3, as recommended by the 2016 ESC guidelines 1.
- Rate control medications typically include beta-blockers (metoprolol 25-100mg twice daily) or calcium channel blockers (diltiazem 120-360mg daily).
- For rhythm control, options include antiarrhythmic drugs like amiodarone, flecainide, or propafenone, or referral for cardioversion or catheter ablation. This comprehensive approach helps identify underlying causes of a-fib while ensuring appropriate management of symptoms and stroke prevention, ultimately prioritizing morbidity, mortality, and quality of life as the outcome.
From the FDA Drug Label
The FDA drug label does not answer the question.
From the Research
Workup for Atrial Fibrillation
The workup for atrial fibrillation (a-fib) involves several steps to diagnose and manage the condition.
- Diagnosis is based on history and physical examination findings and should be confirmed with 12-lead electrocardiography or other recording device 2.
- The initial evaluation should include:
- Transthoracic echocardiography
- Serum electrolyte levels
- Complete blood count
- Thyroid, kidney, and liver function tests 2
- Echocardiography, including transthoracic and transesophageal echocardiography, plays a crucial role in the evaluation and management of a-fib, allowing for the assessment of cardiac structure and function, and the detection of thromboembolic risk 3, 4.
Laboratory Tests and Risk Assessment
- Laboratory tests, such as serum electrolyte levels, complete blood count, and thyroid function tests, are essential in the workup for a-fib 2.
- The CHA2DS2-VASc score is used to assess stroke risk in patients with a-fib 2.
- Thyroid function tests are particularly important, as thyroid disease, especially hyperthyroidism, is a potential underlying cause of a-fib 5.
Imaging Studies
- Echocardiography is a critical imaging modality in the workup for a-fib, providing valuable information on cardiac structure and function, and thromboembolic risk 3, 4.
- Transthoracic echocardiography is recommended for all patients with a-fib, while transesophageal echocardiography may be used in specific situations, such as before electrical cardioversion 3.