Concealed Sinus Node Dysfunction and Paradoxical Effect of Atropine during Arrhythmia Diagnostic Pharmacological
Myriam Karam1, Antoine Kossaify2
1Anesthesia and Critical care Department, University Hospital Notre Dame de Secours, St Charbel street, Byblos, Lebanon.
Clinical Medicine Insights. Case Reports
|September 19, 2014
Summary
Sinus node dysfunction (SND) caused fainting and ventricular bigeminy in a patient. Pacemaker implantation resolved these symptoms, highlighting a link between bradycardia and ventricular ectopy.
Area of Science:
- Cardiology
- Electrophysiology
- Internal Medicine
Background:
- Sinus node dysfunction (SND) can manifest with varied symptoms, including syncope.
- Ventricular ectopy can sometimes be associated with underlying bradyarrhythmias.
- Pharmacological challenges are crucial for diagnosing elusive cardiac conditions.
Observation:
- A 78-year-old male presented with recurrent syncope and persistent ventricular bigeminy on ECG.
- Atropine administration revealed an accelerated junctional rhythm and suppressed ventricular ectopy.
- This paradoxical response suggested concealed SND triggering ventricular hyperexcitability.
Findings:
- The patient was diagnosed with sinus node dysfunction (SND).
- A dual-chamber pacemaker implantation successfully eliminated both syncope and ventricular ectopy.
- Atropine's effect on junctional rhythm was noted as a paradoxical response.
Implications:
- This case underscores the importance of considering SND in patients with unexplained syncope and ventricular ectopy.
- Pacemaker therapy is effective in managing bradycardia-induced ventricular arrhythmias.
- Understanding paradoxical responses to pharmacological agents aids in accurate diagnosis and treatment of cardiac arrhythmias.
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