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[Ineffective atrial pacing and cardiac arrest in a 80-year old woman with hyperkalemia]

Jacek Lelakowski1, Agnieszka Czunko, Jacek Majewski

  • 1Oddział Kliniczny Elektrokardiologii Krakowskiego Szpitala Specjalistycznego im. Jana Pawła II, Kraków.

Polski Merkuriusz Lekarski : Organ Polskiego Towarzystwa Lekarskiego
|September 16, 2005
PubMed

Insights

This case study highlights how severe hyperkalemia in an elderly patient on ACE inhibitors and spironolactone caused ineffective atrial pacing and nodal rhythm. Normalizing potassium levels resolved these electrocardiogram changes.

Area of Science:

  • Cardiology
  • Electrophysiology
  • Nephrology

Background:

  • Elderly patients on dual therapy with angiotensin-converting enzyme (ACE) inhibitors and spironolactone are at risk for hyperkalemia.
  • Pacemaker implantation, particularly AAI mode, can be affected by electrolyte imbalances.

Observation:

  • An 80-year-old woman presented with marked hyperkalemia during chronic treatment with ACE inhibitors and spironolactone.
  • Electrocardiogram (ECG) revealed a nodal rhythm and ineffective AAI pacing, consistent with hyperkalemia.

Findings:

  • Hyperkalemia was the likely cause of the observed ECG abnormalities, including nodal rhythm and ineffective atrial pacing.
  • Normalization of serum potassium levels led to the resolution of all ECG changes.

Implications:

  • Clinicians should be vigilant for hyperkalemia in patients on ACE inhibitors and spironolactone, especially those with pacemakers.
  • Electrolyte disturbances can significantly impact cardiac pacing function and ECG interpretation.

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