[Clinical interpretation of the character of mitral valve flow in relation to diastolic properties of the left ventricle].
- I. interní klinika 3. lékarské fakulty UK, Praha.
Based on their own experience and data in the literature the authors describe the Doppler method of evaluation of properties of the left ventricle. In patients with early disorders of the diastolic function, when above all relaxation of the left ventricle is affected, a reduced rate of early diastolic filling (E) is a typical finding. There is also compensatory increase in the rate of filling during auricular contraction (A) with the appropriate increase of the A/E ratio and the ratio of rate velocity integrals (TVIA/TVIE). At the same time the maximal flow through the mitral orifice is reduced during early diastole (PFR), the deceleration time is protracted and so is the time of isovolumic relaxation. For more advanced stages of cardiac damage when impaired compliance of the left ventricle predominates, typical features are the so-called restrictive type of filling with a high rate of E, short DT and a relatively low velocity A. There exists a number of intermediary types between these extreme types of flow. The final shape of the flow curve is influenced also by the actual haemodynamic condition of the subject (heart rate, pre-load, after-load, pressure in left, ventricle, left ventricular systolic function etc.). The authors draw therefore attention to possible errors during interpretation of assessed indicators. In the conclusion they recommend methodical principles for examination of left ventricular diastolic function by Doppler echocardiography. Above all it is necessary to respect restrictions due to valvular defects, arrhythmias, the action of drugs with haemodynamic action, the presence of signs of left ventricular failure, the influence of respiration on the flow rate, etc.
Keywords: Blood Flow Velocity; Diastole; Echocardiography, Doppler; Humans; Mitral Valve, physiology, ; Myocardial Contraction; Ventricular Function, Left
Published: January 1, 1992 Show citation