e’ Average Calculator

e' Average: Explanation and Clinical Context The e prime average value represents the combined early diastolic mitral annular velocity obtained from the lateral and septal annulus using tissue Doppler imaging. This index provides a quantitative assessment of myocardial relaxation, which is a key determinant of left ventricular diastolic function. Because the lateral annulus typically exhibits higher velocities and the septal annulus tends to produce lower values, averaging both sites produces a more reliable and reproducible measure across different pathological states.

A reduced e prime average indicates impaired myocardial relaxation, which is an early marker of abnormal left ventricular diastolic function. This reduction is commonly seen in hypertensive heart disease, left ventricular hypertrophy, ischemic heart disease, infiltrative cardiomyopathies, and heart failure with preserved ejection fraction. Clinical interpretation often incorporates this value into broader diagnostic frameworks such as the diastolic function algorithm from echocardiography guidelines, where e prime average is used in combination with parameters such as E over e prime ratio, left atrial volume index, and tricuspid regurgitation velocity.

Normal reference values generally include lateral e prime greater than 10 mm per second and septal e prime greater than 7 mm per second. Therefore, the averaged value helps clinicians identify early myocardial relaxation abnormalities even when a single site is borderline. In clinical scenarios, a reduced e prime average is associated with elevated filling pressures, reduced exercise tolerance, and adverse cardiovascular outcomes.