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Updated: Apr 4, 2026
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Whole-Mount Immunofluorescence Staining, Confocal Imaging and 3D Reconstruction of the Sinoatrial and Atrioventricular Node in the Mouse
Published on: December 22, 2020
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Anatomy and pathology of the sinus node
Siew Yen Ho1,2, Damián Sánchez-Quintana3
1Cardiac Morphology, Royal Brompton Hospital, Sydney Street, London, SW3 6NP, UK. syenho@yahoo.com.
Summary
This review details the human sinus node anatomy and its common pathological variations. We highlight age-related changes and fibro-fatty tissue replacement in the sinus node.
Area of Science:
- Cardiovascular Anatomy
- Cardiac Electrophysiology
Background:
- The sinus node is the heart's primary pacemaker.
- Understanding its anatomy is crucial for diagnosing arrhythmias.
Purpose of the Study:
- To review the anatomical features of the human sinus node.
- To examine pathological variations and their clinical implications.
Main Methods:
- Literature review of sinus node anatomy and pathology.
- Analysis of observational data on sinus node characteristics.
Main Results:
- The sinus node is near the right phrenic nerve and nodal artery.
- Nodal cell count decreases with age; pathological changes include fibro-fatty replacement.
- Variations exist in the node's arterial supply and its relation to the cavo-atrial junction.
Conclusions:
- The normal sinus node location is well-established.
- Anatomical variations in the sinus node and its blood supply are recognized.
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