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The role of the Gregg phenomenon in cardiac performance
1Nicolae C. Paulescu Department of Physiology, University of Medicine and Pharmacy Carol Davila Bucharest.
Insights
The Gregg phenomenon, possibly a "garden house"-like effect, may enhance left ventricle performance through sarcomere stretch. This study supports the Gregg effect theory but not as a primary cardiac performance determinant.
Area of Science:
- Cardiology
- Physiology
Background:
- The Gregg phenomenon lacks a complete explanation.
- It is theorized to involve positive inotropic factors released due to shear stress from increased coronary flow.
Purpose of the Study:
- To investigate the Gregg phenomenon's potential role in left ventricle performance.
- To explore the
- garden house
- effect as a mechanism for sarcomere stretch.
Main Methods:
- Coronarography data from 22 patients with coronary obstruction were analyzed.
- Left ventricle performance was assessed during contrast medium injection, increasing coronary bed pressure.
Main Results:
- The study observed increased left ventricle performance in some cases.
- Results support the Gregg effect theory.
- The Gregg effect was not identified as a fundamental determinant of cardiac performance.
Conclusions:
- The
- garden house
- effect is a probable explanation for the Gregg phenomenon.
- While supporting the Gregg effect, this study indicates it's not the sole driver of cardiac performance.
Abstract:
The Gregg phenomenon has not, yet, a full and complete explanation. We are allowed to consider it a "garden house"-like effect. Positive inotropic factors are released as a consequence of "shear stress" phenomenon following an increased coronarian flow. In our study, it is more probably a "garden house"-like effect that causes a sarcomere stretch. This could explain the increased left ventricle performance found, in some circumstances, in our study. We used the data obtained by coronarography in 22 patients carrying various degrees of coronarian obstruction and we assessed the left ventricle performance during the repeated injection of contrast medium, that increases the pressure in the coronarian bed. The results obtained support the theory regarding the Gregg effect but do not allow us to consider this effect as a fundamental determinant of the cardiac performance.