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[Function and reserve of the hypertrophic left ventricle in aortic valve disease]
Insights
Left ventricular function in aortic valve disease depends on the degree of hypertrophy. Moderate hypertrophy maintains normal function, while severe hypertrophy impairs cardiac performance.
Area of Science:
- Cardiology
- Cardiac Physiology
Context:
- Aortic valve disease (AVD) encompasses aortic stenosis and regurgitation, often leading to left ventricular (LV) hypertrophy.
- Assessing LV function is crucial for managing AVD and predicting outcomes.
Purpose:
- To investigate the relationship between the degree of left ventricular hypertrophy and cardiac function in patients with aortic valve disease.
Summary:
- Left ventricular function was assessed using angiography in 31 AVD patients and 12 controls. Parameters included ejection fraction, fractional shortening, mean velocity of fiber shortening, and left atrial pressure. Contractile reserve was tested post-extrasystolic beat. Pure aortic stenosis and regurgitation with moderate hypertrophy (220-260% of normal) showed preserved LV function. However, combined aortic valve lesions with severe hypertrophy (360% of normal) resulted in impaired LV function and elevated left atrial pressure, with persistent depression after a premature beat.
Impact:
- The degree of left ventricular hypertrophy is a key determinant of cardiac function in aortic valve disease.
- Moderate hypertrophy is associated with normal resting cardiac function, whereas severe hypertrophy leads to impaired function, highlighting the importance of hypertrophy severity in AVD management.
Abstract:
Left ventricular function was analyzed by angiography in 31 patients with aortic valve disease and in 12 patients without heart disease (control group). Ejection fraction, percentage shortening of minor equator, mean velocity of fiber shortening and men left atrial pressure were considered as parameters of left ventricular function. Contractile reserve was tested by a single postextrasystolic beat. Patients with pure aortic stenosis and an increase of left ventricular muscle mass to 220% of the normal value showed no impairment of left ventricular function. Patients with pure aortic regurgitation and a left ventricular muscle mass of 260% of normal showed no significantly impaired function. Both groups increased ejection fraction and percentage shortening of the minor equator after premature beat comparable to the control group. Patients with combined lesions of the aortic valve had a left ventricular muscle mass of 360% of normal. This group showed decreased ejection fraction, percentage shortening of minor equator and mean velocity of fiber shortening as compared to the control group while mean left atrial pressure was significantly elevated. After premature beat all parameters remained depressed as compared to control group. We conclude that the degree of hypertrophy determinates cardiac function in aortic valve disease. Moderate hypertrophy shows normal function at rest, while severe hypertrophy shows impaired function.