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Failure of diltiazem to prevent 1:1 conduction of atrial flutter: a case report

K D Tiver1,2, D K Martin3, J Quah1,2

  • 1Department of Cardiology, Flinders Medical Centre, Level 6, Flinders Drive, Bedford Park, SA, 5042, Australia.

Journal of Medical Case Reports
|July 18, 2023
PubMed

Insights

Diltiazem failed to prevent dangerous 1:1 atrial flutter in a patient taking flecainide. This highlights potential risks when combining these anti-arrhythmic drugs for atrial fibrillation management.

Area of Science:

  • Cardiology
  • Pharmacology

Background:

  • Atrial flutter with 1:1 ventricular conduction is a critical arrhythmia.
  • Current guidelines suggest combining AV nodal blockers with Class 1C anti-arrhythmics for prophylaxis.
  • Guidance on AV nodal blockade type and dosage is lacking, leading to suboptimal use.

Observation:

  • A 62-year-old male patient with atrial fibrillation on flecainide presented with 1:1 atrial flutter.
  • Cardioversion was performed, and diltiazem was added for prophylaxis.
  • The patient recurred with 1:1 atrial flutter despite diltiazem prophylaxis.

Findings:

  • Diltiazem failed to prevent 1:1 atrial flutter in a patient on chronic flecainide therapy.
  • This case illustrates a potential drug interaction or inadequate blockade.

Implications:

  • Clinicians should be aware of the potential for diltiazem to fail in preventing 1:1 flutter when used with flecainide.
  • Further research is needed to clarify optimal prophylactic strategies for 1:1 atrial flutter in patients on Class 1C agents.
  • This case underscores the importance of individualized treatment approaches in managing complex cardiac arrhythmias.
Abstract

Keywords:
1:1 conductionAtrial flutterCase reportClass 1cDiltiazemFlecainide

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