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Supernormal ejection performance is isolated to the ipsilateral congenitally pressure-overloaded ventricle
R B Leman1, F G Spinale, G W Dorn
1Department of Medicine, Medical University of South Carolina, Charleston 29425.
Journal of the American College of Cardiology
|May 1, 1989
Summary
Congenital pressure overload in either the right or left ventricle leads to enhanced ejection performance in the overloaded chamber. This study investigated ventricular function in patients with congenital pulmonary or aortic stenosis.
Area of Science:
- Cardiology
- Physiology
- Pediatric Cardiology
Background:
- Congenital left ventricular pressure overload causes hypertrophy and improved ejection performance.
- It is unclear if congenital right ventricular pressure overload causes similar effects.
- The impact of supranormal ejection performance on one or both ventricles is unknown.
Purpose of the Study:
- To investigate whether congenital right ventricular pressure overload is associated with enhanced ejection performance.
- To determine if enhanced ejection performance affects only the overloaded ventricle or both ventricles.
- To explore whether ventricular hypertrophy is due to local loading or neuroendocrine influences.
Main Methods:
- Examined right and left ventricular performance in patients with isolated congenital pulmonary stenosis (n=7) and isolated congenital aortic stenosis (n=6).
- Included a control group of six normal subjects.
- Measured pressure gradients and ejection fractions for both ventricles.
Main Results:
- Right ventricular ejection fraction was significantly increased in patients with pulmonary stenosis compared to normal subjects and aortic stenosis patients.
- Left ventricular ejection fraction was significantly increased in patients with aortic stenosis compared to normal subjects and pulmonary stenosis patients.
- Both ventricles showed increased ejection fraction when overloaded.
Conclusions:
- Congenital pressure overload in either ventricle is associated with enhanced ejection performance in that ventricle.
- The findings suggest that local loading conditions, rather than systemic neuroendocrine influences, primarily drive ventricular hypertrophy in response to pressure overload.
- Both ventricles can exhibit supranormal ejection performance when subjected to pressure overload.