Atrial Flutter with Rapid Ventricular Response (RVR)

Introduction

Atrial flutter (AFL) is a type of supraventricular tachycardia characterized by rapid, organized atrial contractions. When accompanied by rapid ventricular response (RVR), the heart rate can become dangerously high, leading to symptoms such as palpitations, dizziness, and even heart failure.

Mechanism of Atrial Flutter

Atrial flutter arises from a reentrant circuit in the atria, usually within the right atrium. The atria contract very quickly—typically at a rate of 250–350 beats per minute (bpm). The atrioventricular (AV) node filters these impulses, but if conduction is high (e.g., 2:1 conduction), the ventricles may beat at dangerously high rates, leading to RVR.

Symptoms

• Palpitations (fast, irregular heartbeat)
• Shortness of breath
• Dizziness or syncope (fainting)
• Chest discomfort
• Fatigue
• Signs of heart failure (e.g., swelling in legs, difficulty breathing)

Risk Factors and Associations

Patients with certain conditions have a higher risk of developing atrial flutter, including: - Hypertension - Coronary artery disease - Heart failure - Chronic obstructive pulmonary disease (COPD) - Diabetes mellitus - Thyroid disorders (especially hyperthyroidism) - Electrolyte imbalances

Diagnosis

Atrial flutter is diagnosed using an electrocardiogram (ECG/EKG). The hallmark of AFL is sawtooth waves in leads II, III, and aVF. A rapid ventricular rate confirms RVR.

Further tests may include: - Echocardiography to evaluate heart structure and function - Thyroid function tests - Electrolyte levels - Holter monitor for intermittent episodes

Treatment Approaches

1. Rate Control

• Medications such as beta-blockers (e.g., metoprolol) or calcium channel blockers (e.g., diltiazem) slow the ventricular response.
• Used in stable patients when rhythm control is not the primary goal.

2. Rhythm Control

• Electrical Cardioversion: Direct-current (DC) cardioversion can restore normal sinus rhythm, especially if symptoms are severe.
• Antiarrhythmic Drugs: Such as amiodarone or flecainide may help maintain normal rhythm.
• Catheter Ablation: First-line therapy for many patients with recurrent AFL; ablation of the reentry pathway in the right atrium is often curative.

3. Anticoagulation

• Patients with atrial flutter are at increased risk of stroke due to potential clot formation in the atria.
• Anticoagulants such as warfarin, apixaban, or rivaroxaban are prescribed based on stroke risk assessment (CHA₂DS₂-VASc score).

Conclusion

Atrial flutter with RVR is a serious arrhythmia that requires prompt medical attention. Management includes rate control, rhythm regulation, and stroke prevention. Long-term strategies may involve catheter ablation in recurrent cases. Seeking medical evaluation for palpitations or irregular heartbeats is crucial for effective treatment and preventing complications.

Source recommendations

1. American Heart Association (AHA) Guidelines for the Management of Atrial Fibrillation

1. https://www.ahajournals.org/doi/10.1161/CIR.0000000000001193
2. https://professional.heart.org/en/science-news/2023-acc-aha-accp-hrs-guideline-for-the-diagnosis-and-management-of-atrial-fibrillation
3. https://www.heart.org/en/health-topics/atrial-fibrillation
4. https://pubmed.ncbi.nlm.nih.gov/38033089/
5. https://www.acc.org/Latest-in-Cardiology/Articles/2023/11/29/18/58/New-ACC-AHA-Guideline-Focuses-on-Diagnosis-Management-of-AFib-gl-af

2. European Society of Cardiology (ESC) Guidelines for the Diagnosis and Management of Atrial Fibrillation

1. https://www.escardio.org/Guidelines/Clinical-Practice-Guidelines/Atrial-Fibrillation
2. https://academic.oup.com/eurheartj/article/42/5/373/5899003
3. https://www.escardio.org/static-file/Escardio/Guidelines/Documents/ehaa612.pdf
4. https://pubmed.ncbi.nlm.nih.gov/32860505/
5. https://www.ahajournals.org/doi/10.1161/CIR.0000000000001193