LEFT VENTRICULAR GLOBAL FUNCTION INDEX AND BLOOD PRESSURE PARAMETERS IN UNTREATED PATIENTS WITH HYPERTENSION

Abstract

Objective: The left ventricular global function index (LVGFI) is a novel marker that incorporates LV structure in the assessment of LV cardiac performance.Typically, LVGFI is assessed with MRI, but recently proposed a technique for calculating this index by echocardiography. It was previously shown that a decrease in LVGFI may be a predictor of adverse outcomes in young patients with hypertension and a preserved ejection fraction. The study aimed to elucidate the association between LVGFI and the features of the daily profile of blood pressure in untreated patients with essential hypertension (EH). Design and method: We included in the study 104 patients with EH (51 men (49%) and 53 women (51%)). Mean age 58,7 ± 11,73 years. All patients had no history of blood pressure-lowering treatment. All patients underwent echocardiography and ambulatory blood pressure monitoring (ABPM). LVGFI (%) was defined as left ventricular (LV) stroke volume/LV global volume∗100% where LV global volume was calculated as the sum of the LV mean cavity volume ((LV end-diastolic volume + end-systolic volume)/2) and myocardium volume (LV mass/density). End-diastolic and end-systolic volume were obtained using Teichholz method. Results: The mean LVGFI was 30,21 ± 7,32%. We performed a correlation analysis of the main clinical characteristics and parameters of ABPM with LVGFI. We found slight correlation between age (r = -0,215, p = 0,028) and body mass index (r = -0,378, p < 0,0001) with the LVGFI. There were no significant associations between office blood pressure and echocardiography parameters. Also mean daily, daytime and night systolic and diastolic blood pressure were not correlated with LVGFI. The most significant associations were found between ABPM systolic (r = -0,307, p = 0,002) and diastolic (r = -0,355, p < 0,0001) blood pressure variability. Patients with the impaired circadian rhythm of blood pressure by type of over-dipper had the lowest LVGFI (26,84 ± 3,301%) compared with patients with normal circadian rhythm (32,43 ± 6,908%) and non-dipper patients (30,49 ± 7,773%), p = 0,041. Conclusions: Lowering of LVGFI is associated with high blood pressure variability and over-dipper circadian rhythm of blood pressure.