This serves the important function of dampening the pulsatile output of the left ventricle, thereby reducing the pulse pressure systolic minus diastolic arterial pressure.
If the aorta were a rigid tube, the pulse pressure would be very high. Because the aorta is compliant, as blood is ejected into the aorta, the walls of the aorta expand to accommodate the increase in blood volume. As the aorta expands, the increase in pressure is determined by the compliance of the aorta at that particular range of volumes. The more compliant the aorta, the smaller the pressure change during ventricular ejection i. Therefore, aortic compliance is a major determinant, along with stroke volume, of the pulse pressure.
Finally, prior studies revealed that the hemodynamic condition and arterial stiffness might affect the timing of the aortic pressure waves.
Reduced arterial compliance frequently occurs in elderly patients with AS, which contributes to increased afterload, decreased LV function, and low mean pressure gradient. Prospective studies, including larger populations of patients with varying severity of AS, are needed to confirm our findings and investigate the potential role of T LV-Ao as a marker of diagnosis and clinical outcome. Published Online: May 1, Author Contributions: Dr Kapadia had full access to all of the data in the study and takes responsibility for the integrity of the data and the accuracy of the data analysis.
Administrative, technical, or material support: Jobanputra, Harb, Wael, Svensson. No other disclosures were reported. Our website uses cookies to enhance your experience. By continuing to use our site, or clicking "Continue," you are agreeing to our Cookie Policy Continue. Assesment of Aortic Stenosis Severity. View Large Download. Table 1. Table 2. Table 3. Table 4. Recommendations on the echocardiographic assessment of aortic valve stenosis: a focused update from the european association of cardiovascular imaging and the american society of echocardiography.
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SoftChalk About this book Chapter Index. Phases of the Cardiac Cycle: Isovolumetric ventricular contraction a-b : This phase marks the beginning of systole and starts with the appearance of the QRS complex on the EKG and the closure of the AV valves at point a. With all valves closed, the ventricle generates positive pressure without any change in its volume isovolumetric to overcome the semilunar valves resistance that open at point b.
Rapid ejection b-c : As the semilunar valves open at point b , there is a rapid ejection of blood due to increased ventricular contractility. The arterial pressure increases until reaching it maximum at point c.
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