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Regurgitant fraction is the percentage of blood that regurgitates back through the aortic valve to the left ventricle due to aortic insufficiency, or through the mitral valve to the atrium due to mitral insufficiency. It is measured as the amount of blood regurgitated into a cardiac chamber divided by the stroke volume.
Mitral regurgitation, also known as mitral insufficiency or mitral incompetence, is the backward flow of blood from the left ventricle, through the mitral valve, and into the left atrium, when the left ventricle contracts, resulting in a systolic murmur radiating to the left armpit.
Velocity Time Integral is a clinical Doppler ultrasound measurement of blood flow, equivalent to the area under the velocity time curve. The product of VTI (cm/stroke) and the cross sectional area of a valve (cm2) yields a stroke volume (cm3/stroke), which can be used to calculate cardiac output.
Afterload is the mean tension produced by a chamber of the heart in order to contract. It can also be considered as the ‘load’ that the heart must eject blood against. Afterload is, therefore, a consequence of aortic large vessel compliance, wave reflection, and small vessel resistance (LV afterload) or similar pulmonary artery parameters (RV afterload
This can also produce a mid-diastolic murmur, such as in severe mitral regurgitation where a large regurgitant volume in the left atrium can lead to "functional mitral stenosis." Mid-diastolic Austin Flint murmur: An apical diastolic rumbling murmur in patients with pure aortic regurgitation.
Aortic regurgitation causes both volume overload (elevated preload) and pressure overload (elevated afterload) of the heart. [14] The volume overload, due to elevated pulse pressure and the systemic effects of neuroendocrine hormones causes left ventricular hypertrophy (LVH). [9] There is both concentric hypertrophy and eccentric hypertrophy in AI.
Modalities applied to measurement of ejection fraction is an emerging field of medical mathematics and subsequent computational applications. The first common measurement method is echocardiography, [7] [8] although cardiac magnetic resonance imaging (MRI), [8] [9] cardiac computed tomography, [8] [9] ventriculography and nuclear medicine (gated SPECT and radionuclide angiography) [8] [10 ...
A Wiggers diagram modified from [1]. A Wiggers diagram, named after its developer, Carl Wiggers, is a unique diagram that has been used in teaching cardiac physiology for more than a century.