Noninvasive Structural and Valvular Abnormality Detection System based on Flow Aberrations

Embodiments provide a reliable, convenient, noninvasive, and cost-effective determination of structural and valvular abnormalities in the left ventricular outflow tract. Embodiments obtain a noninvasive optical pulse plethysmogram from the systolic and diastolic phases of the cardiac cycle for subsequent morphologic waveform analysis to determine left ventricular outflow tract anomalies. Left ventricular outflow tract abnormalities alter the rate of increase in flow during early systole and decrease in flow during late systole. These flow variances at the aortic valve are amplified as the pulse wave moves to the periphery due to a combination of the ventricular-aortic interaction, pulse augmentation, and reflections at branching vessels and changes in diameter. The invention addresses historical limitations in the noninvasive determination of structural and valvular abnormalities in the left ventricular outflow tract by using one or more of (1) improved optical measurement systems, (2) peripheral sampling locations that maximize signal differences, (3) volitional patient maneuvers to improve the diagnostic ability of the system, and (4) pulse enhancement techniques. The resulting test system can be used to determine the presence of abnormalities and to diagnose the type of abnormality. The ability to more efficiently and effectively diagnose aortic stenosis, the most common abnormality, in the primary care clinic will result in fewer patients experiencing complications such as heart failure, heart attack, and sudden death.