Diastolic function is defined as/describes the filling of the heart during diastole

is defined as/describes the filling of the heart during diastole. The left ventricle is filled with blood initially by a pressure gradient between the left atrium (LA) and the left ventricle (LV). Especially ventricles of young healthy individuals also create suction in the very early phase of filling due to rapid expansion of the LV. In between passive and active filling of the left ventricle there is a period of time where only little filling occurs, the so called diastasis.
#diastolic_dysfunction
is impaired left ventricular relaxation with increased stiffness of the LV and elevated filling pressures.
#Grading_of_diastolic_dysfunction:
*Grade I diastolic dysfunction, impaired relaxation: First stage of diastolic dysfunction. Decreased suction of the LV.
*Grade II diastolic dysfunction, pseudonormalization: Increased stiffness of the LV, elevated LAP.
*Grade III, restrictive filling (reversible): High LAP, noncompliant LV. May be reversible with reduction of preload (e.g. diuretics).
*Grade IV, restrictive filling (irreversible): As stage III with no benefit from reduction of preload.#Grading_of_diastolic_dysfunction:
*Grade I diastolic dysfunction, impaired relaxation: First stage of diastolic dysfunction. Decreased suction of the LV.
*Grade II diastolic dysfunction, pseudonormalization: Increased stiffness of the LV, elevated LAP.
*Grade III, restrictive filling (reversible): High LAP, noncompliant LV. May be reversible with reduction of preload (e.g. diuretics).
*Grade IV, restrictive filling (irreversible): As stage III with no benefit from reduction of preload
.#Assesment_of_diastolic_dysfunction:
There are various variables to assess diastolic function using corresponding pathological cut off values:
*Mitral E/A ratio - cut off value: ≤ 0.8 & > 2
*Peak E velocity - cut off value: > 50 cm/sec
*Deceleration time (DT) - cut off value: 140 - 240 msec
*e´ - cut off values: septal < 7cm/sec, lateral < 10cm/sec
*E/e´ ratio - cut off value: average > 14 (septal >15 , lateral >13)
*Left atrial (LA) *maximum volume index - cut off value: 34mL/m2
*Peak tricuspid regurgitation (TR) velocity - cut off value: > 2.8m/sec
*Isovolumetric relaxation time (IVRT) - cut off value: ≤ 70 mm/sec - >100 mm/sec
*pulmonary venous S/D ratio - cut off value: < 1
*Ar - A duration - cut off value: >30 msec