From the Guidelines
For a new onset atrial flutter workup, start with a 12-lead ECG to confirm the diagnosis, looking for the characteristic "saw-tooth" pattern of flutter waves, typically at a rate of 300 beats per minute, as recommended by the 2015 ACC/AHA/HRS guideline for the management of adult patients with supraventricular tachycardia 1. Next, assess the patient's hemodynamic stability. If unstable, prepare for immediate cardioversion.
Initial Assessment
- Order basic blood tests including complete blood count, electrolytes, thyroid function tests, and cardiac biomarkers.
- Perform a chest X-ray to evaluate for underlying pulmonary disease or heart failure.
- Echocardiography is crucial to assess cardiac structure and function, looking for valvular abnormalities, left atrial enlargement, or ventricular dysfunction.
Rate Control
- Initiate rate control with medications such as beta-blockers (e.g., metoprolol 25-50 mg orally twice daily) or calcium channel blockers (e.g., diltiazem 30-60 mg orally four times daily), as recommended by the 2015 ACC/AHA/HRS guideline 1.
- Assess stroke risk using the CHA2DS2-VASc score and consider anticoagulation if the score is 2 or greater for men, or 3 or greater for women, as recommended by the 2014 AHA/ACC/HRS guideline for the management of patients with atrial fibrillation 1.
- Options include direct oral anticoagulants like apixaban 5 mg twice daily or warfarin with a target INR of 2-3.
Further Workup
- Further workup should include a thorough history and physical examination to identify potential triggers or underlying conditions such as hyperthyroidism, pulmonary embolism, or recent surgery.
- Consider additional tests like a stress test or coronary angiography if ischemic heart disease is suspected.
- Develop a plan for rhythm control, which may involve electrical cardioversion after appropriate anticoagulation, or pharmacological cardioversion with agents like amiodarone or flecainide under close monitoring, as recommended by the 2015 ACC/AHA/HRS guideline 1.
- Discuss long-term management options, including catheter ablation for recurrent or persistent atrial flutter.
Rhythm Control
- Elective synchronized cardioversion is indicated in stable patients with well-tolerated atrial flutter when a rhythm-control strategy is being pursued, as recommended by the 2015 ACC/AHA/HRS guideline 1.
- Synchronized cardioversion is recommended for acute treatment of patients with atrial flutter who are hemodynamically unstable and do not respond to pharmacological therapies, as recommended by the 2015 ACC/AHA/HRS guideline 1.
From the Research
Initial Evaluation of Atrial Flutter
The initial evaluation of atrial flutter (AFL) involves several key components, including:
- Electrocardiogram (ECG) to confirm the diagnosis and determine the type of AFL 2
- Assessment of cardiac function, valvular and ischemic heart disease, and thyroid, kidney, and liver function 3
- Evaluation of the patient's medical history, including any previous arrhythmias or cardiac conditions 4
Importance of Accurate Diagnosis
Accurate diagnosis of AFL is crucial to prevent misdiagnosis and unnecessary treatment 5. ECG artifacts can mimic AFL, and careful review of the ECG by a cardiologist is necessary to confirm the diagnosis.
Predictive Value of ECG Parameters
Certain ECG parameters, such as the duration of the negative component of flutter wave in lead II (DFNII) and P wave duration in lead II (DPII), have been found to be independently associated with new-onset atrial fibrillation (AF) after typical AFL ablation 6.
Guideline-Recommended Evaluation
Guidelines recommend a comprehensive evaluation of patients with newly diagnosed AFL, including:
- Basic evaluation, including physician visit, electrocardiogram, and echocardiography 3
- Laboratory testing, including thyroid function tests 3
- Assessment of cardiac function and valvular and ischemic heart disease 4, 3
Completion of Guideline-Recommended Evaluation
Completion rates for guideline-recommended evaluations vary, with basic evaluation completed in up to 66.6% of patients and all guideline-recommended evaluations completed in 17.4% to 18.5% of patients 3. Increasing the observation period to 1 year before through 3 months after the AFL diagnosis can increase completion rates.