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Isolation of Human Atrial Myocytes for Simultaneous Measurements of Ca2+ Transients and Membrane Currents
10:53

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Published on: July 3, 2013

Intrahissian anisotropy and second degree type I block

Jeffrey L Williams1, David Lugg, Robert Gray

  • 1Good Samaritan Health System, Lebanon Cardiology Associates, 775 Norman Drive, Lebanon, PA 17042.

Indian Pacing and Electrophysiology Journal
|June 17, 2010
PubMed

Insights

This study reports a rare case of a patient experiencing both intrahissian Wenckebach and anisotropy, leading to syncope. A dual-chamber pacemaker successfully treated these cardiac conduction abnormalities.

Area of Science:

  • Cardiology
  • Electrophysiology
  • Cardiac Electrophysiology

Background:

  • Syncope can result from various cardiac conduction abnormalities.
  • Intrahissian Wenckebach and anisotropy are distinct electrophysiological phenomena affecting cardiac conduction.

Purpose of the Study:

  • To report the first documented case of co-occurring intrahissian Wenckebach and anisotropy in a single patient presenting with syncope.
  • To highlight the diagnostic and therapeutic approach for complex conduction disorders.

Main Methods:

  • Invasive electrophysiologic study was performed to evaluate the cause of syncope.
  • Diagnostic criteria for intrahissian Wenckebach and anisotropy were applied.
  • Dual-chamber pacemaker implantation was performed.

Main Results:

  • Electrophysiologic evaluation confirmed the presence of both intrahissian Wenckebach and anisotropy in the patient.
  • The patient experienced multiple episodes of witnessed syncope attributed to these conduction abnormalities.
  • Dual-chamber pacemaker implantation was technically successful and without immediate complications.

Conclusions:

  • The simultaneous occurrence of intrahissian Wenckebach and anisotropy is a rare but significant finding in patients with syncope.
  • Electrophysiologic studies are crucial for diagnosing complex conduction disturbances.
  • Pacemaker implantation is an effective treatment for syncope caused by these conditions.

Keywords:
AnisotropyIntrahissianPacemakerSecond Degree Block

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