الفهرس 
introduction and literature reviewOnly 14 pages are availabe for public view
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Abstract
A data processing system is established to quantitatively analyze the pattern of inflow velocity to the left ventricle through the mitral valve. Since the filling phase of the left ventricle results from a complex interplay between different parameters Including the left atrial and left ventricular pressures which in turn are affected by ventricular geometry and dispensability, the study is conducted on typical wave forms For Normal Physiological Conditions And For Two Pathological Conditions: A) Hypertrophied Left Ventricle In Which The Geometry And Elastic Properties Of The Left Ventricular Wall Are Altered And B) Constricted (Stenotic) Mitral Valve. The Fast Fourier Transform (FFT) Method Is Applied To Resolve The Velocity time Signals To Their Harmonic Components. The Re-Synthesis Of The Original Curves From Ten Harmonics Demonstrated A Great Deal Of Accuracy. Under Normal Conditions The First Three Harmonics Contribute To More Than 95% Of Signal Variance. The Number Of Harmonics Required To Approach The Velocity Pattern Increases Under Abno11i1al Conditions. The Results Suggest That The Ratios Of Amplitudes And Phase Angles Between The Periodic Components May Provide Characterizing).G Parameters Discriminating Normal From Abnormal Conditions. The Study Also Proposed A Very Simple Approach To Obtain The Pattern Of Left Ventricular Filling It Is Based On Expressing The Change Of Left Ventricular Volume As A Ratio Of The Stroke Volume By Integrating The Velocity-Time Signal At Successive Moments During The Filling Phase. The Filling Of The Left Ventricular Cavity Showed Three Distinguished Patterns Reflecting The Effect Of Decreased Left Ventricular Compliance And Constricted Valve Orifice Area On The Filling Characteristics Of The Left Ventricular Chamber. The Agreement Of The Present Results With Previous Studies Employing Different Techniques Such As Magnetic Resonance Imaging (MRI), Gated Blood Pool Cardiac Scintigraphy, Automated Border Detection (ABD) And Cine Computed Tomography (CT) Justifies This Methodology Which Involves Simple Clinical Procedures And Less Tedious Computations.