Background: Mitral inflow velocity, deceleration time, and isovolumic relaxation time recorded by Doppler echocardiography have been widely used to evaluate left ventricular diastolic function but are affected by age, heart rate, loading conditions, and other factors. The diastolic mitral anulus velocity assessed by tissue Doppler echocardiography (TDE) was suggested to provide additional information about LV relaxation less affected by filling pressures.
Aim of the study: This study was designed to assess the clinical utility of mitral anulus velocity in the evaluation of left ventricular diastolic function.
Patients and methods: Three groups of patients with a systolic ejection fraction > 45% were separated: 10 normal volunteers (60 +/- 10 y, CON group), 15 asymptomatic patients with known coronary artery disease (60 +/- 11 y, CAD group) and 15 patients with long-term arterial hypertension and heart failure symptoms (58 +/- 9 y, HYP group). The mitral inflow profile (E, A, E/A) was measured by pulsed Doppler, and the deceleration time (DT) and the isovolumic relaxation period (IVRT) were calculated. Systolic, early, and late diastolic velocities of the septal mitral anulus (ST, ET, AT, ET/AT) were assessed by pulsed TDE. All study subjects had invasive measurements of left ventricular end diastolic filling pressures during left heart catheterization.
Results: In the AH group, ET (6.9 +/- 4.8 cm/s) and ET/AT (0.71 +/- 0.28) were reduced compared to the CON group (11.7 +/- 4.7 cm/s and 1.11 +/- 0.36, p < 0.05, respectively) and the CAD group (8.9 +/- 5.4 cm/s and 0.85 +/- 0.26, respectively, p = ns). The groups did not differ with respect to the mitral E/A ratio, the deceleration time and the isovolumic relaxation time. LVED in the HYP group (16 +/- 8 mm Hg) was elevated compared to the CON group (8 +/- 3, p < 0.05) and the CAD group (12 +/- 6 mm Hg, p = ns). No correlation was found between ET and LVED (r = 0.26). When the combination of mitral E/A ratio > 1 with LVED > or = 15 mm Hg was classified as pseudonormalization, the pseudonormalization could be identified by a peak early diastolic mitral anulus velocity (ET) < 7 cm/s and an ET/AT ratio < 1 with a sensitivity of 77% and a specificity of 88%.
Conclusions: The early diastolic mitral anulus velocity assessed by TDE (ET) is a preload-independent index of LV relaxation. TDE permits the detection of diastolic dysfunction in patients with a pseudonormal mitral inflow and elevated filling pressures.