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Temporal changes of the diameter of the coronary sinus during the cardiac cycle
Rafal Mlynarski1,2, Agnieszka Mlynarska2,3, Bartłomiej Stasiow4
1Department of Electrocardiology and Heart Failure, School of Health Sciences, Medical University of Silesia, Katowice, Poland.
Insights
The size of the coronary sinus (CS) changes throughout the cardiac cycle. This study found the CS is largest around the 40% RR interval phase, offering insights into cardiac venous system dynamics.
Area of Science:
- Cardiovascular Imaging
- Cardiac Anatomy
- Venous System Research
Background:
- No prior studies have analyzed cardiac venous system changes based on the cardiac cycle phase.
- Understanding these dynamics is crucial for accurate anatomical assessments.
Purpose of the Study:
- To evaluate the size variations of the coronary sinus (CS) at two distinct measurement points.
- To determine if CS dimensions are dependent on the specific phase of the cardiac cycle (RR interval).
Main Methods:
- Fifty patients underwent cardiac computed tomography (CT) using a dual-source Siemens Somatom Force scanner.
- Coronary sinus ostium and trunk dimensions were measured in millimeters using "MM reading" presets.
- Measurements were analyzed on axial scans across the 0%-100% RR interval.
Main Results:
- The coronary sinus (CS) exhibited its largest dimensions at the 30%, 40%, and 50% RR interval phases in 74% of patients.
- The 40% RR interval phase showed the largest CS size in the majority of cases (34%).
- No significant gender-related differences in CS size were observed relative to the cardiac cycle phase.
Conclusions:
- The size of the coronary sinus demonstrates significant variability depending on the cardiac cycle phase.
- The 40% RR interval phase is consistently associated with the largest coronary sinus dimensions in most individuals.
Introduction:
Currently, there are no studies that analyse the changes in the cardiac venous system that are dependent on the phase (RR interval) of reconstruction. The aim of the study was to assess the size of the coronary sinus at two measurement sites depending on the phase of the heart cycle.
Methods:
Fifty patients were included. Cardiac computed tomography was performed in all of the patients due to a suspicion of coronary artery disease (typical indications) using a dual-source Siemens Somatom Force scanner. The "MM reading" presets were used to measure the coronary sinus ostium (measurement 1) and the coronary sinus trunk, which is close to the great cardiac vein (measurement 2) in millimetres. All of the calculations were performed on axial scans using 0%-100% and a 256 × 256 matrix.
Results:
The largest CS was found at the 30%, 40% and 50% RR interval-this phenomenon occurred in 37 of the 50 cases (74%). The CS was largest in the 30% phase (9/50 cases; 18%), in the 40% phase (17/50 cases; 34%) and in the 50% phase, and it was the largest in 11 of the 50 cases (22%). There were also no gender-related differences.
Conclusions:
The size of the coronary sinus varies with the phase of the heart cycle. At the 40% phase, it is largest in most cases.
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