Percentage of Left Ventricular Stroke Work Loss
نویسنده
چکیده
The ratio of the mean systolic transaortic valvular gradient to the mean systolic left ventricular pressure times 100 yields a percentage that represents the portion of left ventricular pressure-volume work per stroke lost because of outflow-tract obstruction. The percentage of the left ventricular stroke work loss and the area of the aortic orifice have been estimated in 49 patients with aortic valvular stenosis and two open-chest dogs with varying degrees of supravalvular aortic constriction. Left ventricular stroke work loss of 30% or greater was associated with calculated aortic valve areas of 1.0
منابع مشابه
Hypereosinophilic Cardiac Involvement Presenting With Left Ventricular Massive Thrombus and Cardioembolic Stroke: A Case Report
Introduction: It is well known that the tendency toward thrombosis is increased in cancer patients. The increase in cancer procoagulant and tissue factor levels, endothelial damage, and stasis due to compression are among the most accused causes of thrombosis in cancer patients. Hypereosinophilia is a rare condition that causes endothelial damage leading to thrombosis. <s...
متن کاملVentricular stroke work loss: validation of a method of quantifying the severity of aortic stenosis and derivation of an orifice formula.
Because aortic stenosis results in the loss of left ventricular stroke work (due to resistance to flow through the valve and turbulence in the aorta), the percentage of stroke work that is lost may reflect the severity of stenosis. This index can be calculated from pressure data alone. The relation between percent stroke work loss and anatomic aortic valve orifice area (measured by planimetry f...
متن کاملDesign an Equivalent Left Ventricular Assist Device for Medical Equipment Labs
LVAD is a mechanical pump supporting a weak heart function and blood flow. Sometimes, the heart may not recover fast enough to take over the pumping action immediately after surgery, in such patients a temporary support device has been employed to maintain the pumping action until the patient’s own heart recovers. This device can be considered as a temporary alternative before the process of ar...
متن کاملDoppler echocardiography markedly underestimates left ventricular stroke work loss in severe aortic valve stenosis.
AIMS Left ventricular (LV) stroke work loss (SWL) is an index of aortic stenosis (AS) severity based on the energy loss concept. Traditionally known as an invasive measurement, SWL has also been determined noninvasively using Doppler echocardiography. The present work was done to compare the echocardiographic estimate against the standard invasive SWL. METHODS AND RESULTS We determined SWL in...
متن کاملPressure-flow studies in man: effect of atrial systole on left ventricular function.
In order to evaluate the effects of atrial contraction on left ventricular function, the pressure gradient technique was used to measure instantaneous aortic blood flow and pressure in nine patients, six having complete heart block and three having normal sinus rhythm. From these data both left ventricular stroke volume and stroke work were calculated. Ventricular rate was controlled by transve...
متن کامل