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Intraventricular conduction disturbances and paroxysmal atrioventricular block in a young patient with MELAS

Stefania Reato1, Sara Spartà, Daniele D'Este

  • 1aCardiology Unit bNeurology Unit, Civic Hospital, Dolo, Venice, Italy Riviera XXIX Aprile 2 30031 Dolo, Venice, Italy.

Journal of Cardiovascular Medicine (Hagerstown, Md.)
|November 19, 2010
PubMed

Insights

Mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes (MELAS) can cause heart rhythm problems like atrioventricular block. Early pacemaker consideration is vital for MELAS patients with worsening heart conduction issues.

Area of Science:

  • Cardiology
  • Neurology
  • Genetics

Background:

  • Mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes (MELAS) is a multisystem disorder.
  • Cardiac involvement in MELAS is increasingly recognized.

Observation:

  • A 36-year-old male with MELAS presented with syncope and intraventricular conduction disturbances.
  • The patient developed paroxysmal atrioventricular block.

Findings:

  • This case highlights that conduction system abnormalities, including atrioventricular block, can be a feature of MELAS.
  • Rapid progression of atrioventricular block was observed in this patient.

Implications:

  • MELAS patients with cardiac conduction anomalies require prompt evaluation for pacemaker implantation.
  • Age should not be a barrier to considering pacemaker intervention in MELAS patients with severe conduction defects.

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