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Updated: Jun 16, 2026
09:20
Microelectrode Array Recording of Sinoatrial Node Firing Rate to Identify Intrinsic Cardiac Pacemaking Defects in Mice
Published on: July 5, 2021
Variation in the blood supply of the sinus node
Christos E Nerantzis1, Hector Anninos, Philipp N Koutsaftis
1Forensic Medical Service of Athens, Micras Asias 75, Sirou 3, 112 57, Athens, Greece. theano9@otenet.gr
Surgical and Radiologic Anatomy : SRA
|February 17, 2010
Summary
This study details anatomical variations in sinus node artery supply, revealing a rare case of dual arteries from the left circumflex coronary artery. This finding is crucial for cardiac surgeons and interventional cardiologists.
Area of Science:
- Cardiovascular Anatomy
- Coronary Artery Anatomy
Background:
- The sinus node artery's origin is critical for cardiac electrical conduction.
- Variations in sinus node artery supply can impact surgical planning and clinical outcomes.
Purpose of the Study:
- To investigate anatomical variations in the blood supply to the sinus node.
- To document the prevalence of different sinus node artery origins.
Main Methods:
- Gross anatomical examination of 400 human hearts.
- Postmortem angiographic evaluation of coronary artery anatomy.
Main Results:
- The sinus node artery originated from the right coronary artery (245 cases) or left circumflex artery (147 cases).
- In 8 cases, the sinus node artery arose from both coronary arteries.
- A previously unreported case featured two sinus node arteries originating from the left circumflex artery.
Conclusions:
- Demonstration of a unique anatomical variation: dual sinus node arteries from the left circumflex coronary artery.
- Highlights the clinical significance of sinus node artery variations for interventional cardiologists and cardiac surgeons.
- Emphasizes the importance of detailed anatomical knowledge for precise surgical procedures.
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