[Relationship between systolic and diastolic function of the left ventricle in patients with impaired relaxation of the left ventricle without symptoms of heart failure. Attempt at quantitative estimation of diastolic function in the impaired relaxation stage].

UNLABELLED

Diastolic dysfunction of left ventricle appears very often in patients with coronary artery disease (CAD) and hypertension (HT) and is a main cause of heart failure in 30-40% of all cases. Relation between systolic and diastolic function of left ventricle (LV) is commonly known but not documented well enough. Moreover, no quantitative classification of diastolic dysfunction is still available.

AIM OF THE STUDY

To find out the relations between the parameters of systolic and diastolic function of LV in patients with CAD or HT with impaired relaxation of LV without symptoms of heart failure and to make up the quantitative classification of diastolic dysfunction in the stage of impaired relaxation of LV.

METHODS

Investigations were carried out in 57 patients (mean age 55.5 +/- 11.5) with angiographically proven CAD and in 91 patients (mean age 56.3 +/- 10.6) with HT and angiographically excluded CAD, all without regional myocardial contractility abnormalities and valvular heart diseases. Control group consisted of 54 healthy subjects (mean age 55.4 +/- 11.4). During 2D echocardiography examination left ventricular end-diastolic (LVEDD) and end-systolic diameters (LVESD) and left atrial dimension (LA) were obtained. Using Doppler method transmitral inflow indices: E velocity (E), A velocity (A), E velocity integral (E-VTI), A velocity integral (A-VTI), total velocity integral (T-VTI), E deceleration time (DT), isovolumic relaxation time (IVRT) and aortic flow velocity integral (Ao-VTI) were measured. Only patients with E/A < or = 1 and--to exclude pseudonormalization of mitral inflow--with DT > or = 140 ms were qualified to the study. We proposed diastolic dysfunction ratio (DDR) calculated from formula: DDR = E/A x E-VTI/T-VTI. Using AFVI, LV outflow diameter, heart rate (HR) and body surface area cardiac index (CI) was calculated.

RESULTS

In studied group there were significantly higher values of LA, A, IVRT, DT and lower values of E, E/A, E-VTI and DDR compared to controls. There were no significant differences between these groups in HR, LVEDD, LVESD, T-VTI and CI. No significant differences in any of studied parameters were found between subgroups with CAD and HT. Among healthy subjects in subgroup with abnormal mitral inflow pattern (E/A < or = 1) there were significantly higher values of LA, IVRT, DT and lower values of DDR than in sugroup with normal one. Both subgroups did not differ in LVEDD, LVESD, CI. In the studied group there was positive correlation between DDR and CI (r = 0.69, p < 0.001), DDR and IVRT (r = 0.71, p < 0.001), DDR and DT (r = 0.61, p < 0.001), CI and E (r = 0.34, p < 0.01), CI and IVRT (r = 0.52, p < 0.001), CI and DT (r = 0.42, p < 0.001), CI and E/A (r = 0.54, p < 0.001), CI and E-VTI (r = 0.43, p < 0.001). In the control group significant correlation was found only between DDR and IVRT (r = 0.64, p < 0.02) and between DDR and DT (r = 0.52, p < 0.02) but not between DDR and CI. Using DDR DD was divided into 3 classes: class I with DDR > 0.47, class II with 0.47 > or = 0.30, and class III with DDR < 0.30. Applying of such intervals of values of DDR determined the groups which significantly differed between themselves in CI, IVRT and DT.

CONCLUSIONS

(1) In patients with CAD or HT with impaired relaxation of LV without symptoms of heart failure there is relation between parameters of systolic and diastolic function of LV: the more advanced diastolic dysfunction, the more impaired systolic function. (2) In healthy subjects there is no relation between parameters of systolic and diastolic function of LV. (3) DDR is a good indicator of quantitative estimation of diastolic dysfunction in the stage of impaired relaxation of LV.