What does impedance cardiography add more to the assessment of left ventricular diastolic function in essential hypertension?

Left ventricular diastolic dysfunction (LVDdf) and arterial stiffness are associated with increased mortality in patients with arterial hypertension.

The aim: of the study was to evaluate the relation between left ventricular diastolic function and hemodynamic profile assessed by impedance cardiography (ICG).

Material and methods: In 209 hypertensives clinical evaluation, echocardiography and ICG were performed to evaluate i.e. septal annulus early diastolic velocity (e'), mitral flow ratio (E/A), stroke index (SI), acceleration index (ACI), velocity index (VI), Heather index (HI), total arterial compliance.

Results: Left ventricular diastolic dysfunction was associated with lower SI (p=0.049), VI (p=0.002), ACI (p=0.014), HI (p=0.002) and higher SVRI (p=0.004). There were no significant differences in age, blood pressure, BMI, sex distribution. Males with LVDdf characterized with lower SI (p=0.011), VI (p<0.00001), ACI (p=0.0005), HI (p=0.00005) and higher SVRI (p=0.008). No such relevant differences were observed in women. In the analysis of the relations between clinical/hemodynamic features and echocardiographic indices of left ventricular diastolic function the significant correlations were observed in males, the most relevant for: age vs E/A (-0.45; p<0.001), VI vs e' (0.30; p<0.001), VI vs E/A (0.30; p<0.001), and SVRI vs e' (-0.28; p<0.001).

Conclusions: Impedance cardiography revealed to be useful in the evaluation of impaired left ventricular performance and increased arterial stiffness related to LVDdf in young and middle-aged hypertensives. Sex may influence cardiovascular hemodynamics resulting in slightly different ventricular-vascular interactions that should be considered in therapeutic strategies.