Atrial arrhythmias can be challenging to manage in any patient—but when they occur in post-transplant recipients, the complexity rises significantly. Immunosuppressive medications, altered cardiac physiology, and long-term metabolic changes often blur the lines between typical cardiac care and transplant-specific concerns.

This blog delves into a real-world case of persistent atrial flutter in a liver transplant recipient, exploring the clinical decision-making, diagnostic clarity, and interventional precision that ultimately led to a successful outcome.

Understanding the Clinical Background

The Patient

A middle-aged liver transplant recipient presented with persistent palpitations that had been ongoing for over a year. Despite stable graft function and no recent transplant complications, the palpitations were significantly impacting the patient’s quality of life.

Medical History

  • Liver transplant: Done approximately 4 years ago for alcoholic cirrhosis

  • Medications: Tacrolimus, mycophenolate mofetil, low-dose steroids

  • No prior cardiac history before transplantation

  • ECG findings: Showed typical atrial flutter with a ventricular response of ~130 bpm

Initial Management Approach

Medical Therapy

The patient was initially started on rate control therapy using a combination of beta-blockers and calcium channel blockers. However, due to persistent symptoms and fluctuating ventricular rates, the strategy was escalated to rhythm control.

Cardioversion

Direct Current Cardioversion (DCCV) was performed using 200J biphasic shock, successfully restoring sinus rhythm. Unfortunately, the patient relapsed into atrial flutter within 2 months.

Clinical Challenge

The early recurrence despite rhythm control raised red flags. In transplant recipients, certain arrhythmias may be persistent due to metabolic changes, atrial scarring, or inflammation. The team had to weigh the risks of long-term antiarrhythmic therapy against the procedural option of catheter ablation.

Diagnostic Electrophysiology Study

The patient was scheduled for a 3D electroanatomic mapping study, with a plan for ablation if appropriate.

Key Findings:

  • A counterclockwise cavotricuspid isthmus (CTI)-dependent atrial flutter was identified.

  • This is the most common form of typical atrial flutter, often amenable to ablation.

  • No signs of atrial thrombus were seen on pre-procedure transesophageal echocardiography.

Catheter Ablation Procedure

Procedural Details:

  • A 3D mapping system was used to delineate the macro-reentrant flutter circuit.

  • Radiofrequency (RF) ablation was targeted at the CTI between the tricuspid valve annulus and the inferior vena cava.

  • Extensive linear ablation was performed until bidirectional conduction block was confirmed.

Outcome:

  • The tachycardia terminated mid-procedure.

  • Post-ablation testing showed no inducible atrial flutter.

  • The patient remained hemodynamically stable throughout.

Post-Procedure Course

Immediate Recovery

  • Continued on low-dose beta-blockers for ventricular control

  • Immunosuppressants were not interrupted

  • Anticoagulation was maintained with apixaban due to CHA₂DS₂-VASc score

Long-Term Follow-Up

At 6 months post-ablation:

  • The patient remained in sinus rhythm

  • No recurrence of palpitations

  • Quality of life improved dramatically

  • Liver graft remained stable

Clinical Reflections

Managing atrial flutter in post-transplant patients demands a multidisciplinary approach:

Considerations:

  • Drug interactions: Antiarrhythmics like amiodarone can interact with tacrolimus.

  • Electrolyte disturbances: Common in liver transplant recipients and can precipitate arrhythmias.

  • Hemodynamic fragility: These patients often cannot tolerate persistent tachycardia.

Why Ablation Was Preferred:

  • Lower long-term medication burden

  • High success rate for typical CTI flutter

  • Avoidance of potential toxic drug interactions

  • Durable rhythm control

Key Takeaways

Feature Relevance
Post-transplant status Higher risk for arrhythmias
Typical CTI flutter Responds well to ablation
Medical management failed DCCV relapse within 2 months
RF ablation Achieved durable success
Ongoing immunosuppression Managed without interruption

Frequently Asked Questions (FAQs)

1. Is atrial flutter common in liver transplant patients?

Yes. Though not universal, atrial flutter and other arrhythmias can occur due to post-operative changes, metabolic imbalances, or side effects of immunosuppressants.

2. Why not just use antiarrhythmic medications long term?

Many antiarrhythmic drugs interact with immunosuppressants or cause liver toxicity. Ablation, especially for CTI-dependent flutter, offers a safer and more definitive solution.

3. Can immunosuppressive drugs cause arrhythmias?

Yes. Medications like tacrolimus and cyclosporine can lead to electrolyte disturbances (especially magnesium and potassium), increasing the risk of arrhythmias.

4. Is catheter ablation safe in transplant recipients?

With proper preparation and monitoring, yes. These procedures are routinely done even in patients with complex medical histories, provided transplant function is stable.

5. How do you monitor for recurrence after ablation?

Through regular ECGs, Holter monitoring if symptoms return, and continuous evaluation of graft function to rule out systemic causes of any new symptoms.

6. What is CTI-dependent flutter?

It’s a type of atrial flutter where the reentrant circuit passes through the cavotricuspid isthmus, an area between the tricuspid valve and inferior vena cava. It’s highly amenable to catheter ablation.

7. Can this patient stop anticoagulation now?

Not necessarily. Stroke risk depends on the patient’s CHA₂DS₂-VASc score, not just rhythm. Many patients remain on anticoagulation despite sinus rhythm restoration.

8. How is this different from atrial fibrillation?

Atrial flutter is usually more organized and has a predictable reentrant circuit. Atrial fibrillation is chaotic and may require different strategies for ablation or rhythm control.

9. What’s the risk of recurrence after ablation?

For CTI-dependent flutter, recurrence rates are low—usually under 10% if bidirectional block is achieved.

10. Can the ablation procedure affect the liver transplant?

No direct effect, but close coordination with the transplant team is essential to avoid drug interactions, monitor immunosuppression, and ensure peri-procedural stability.