Microalbuminuria, Pulse Pressure, Left Ventricular Hypertrophy, and Myocardial Ultrasonic Tissue Characterization In Essential Hypertension

Abstract

Microalbuminuria (UAE) may be considered a marker of systemic vascular dysfunction, while pulse pressure (PP) is an indicator of the stiffness of vascular conduits. Both these parameters, together with left ventricular hypertrophy (LVH), are linked to cardiovascular morbidity in hypertensive patients. The aim of this study was the analysis of the possible relationships among UAE, PP, and LVH with ultrasonic myocardial textural parameters, which are altered in hypertensives patients. A group of male (n = 70) essential hypertensive patients (mean age: 58 +/- 7 yr) was analyzed with a group of age-comparable normotensive healthy subjects as controls (n = 32). Ambulatory blood pressure monitoring (ABPM) was performed with an oscillometric monitor; UAE was measured by nephelometry. A conventional 2D-Doppler echocardiography (to analyze left ventricular mass: LVM) and a quantitative analysis of the echocardiographic digitized imaging with the use of a calibrated digitization system (to calculate the septum and the posterior wall textural parameters) were performed on all subjects. The myocardial mean gray level was calculated to derive the cyclic variation index (CVI). The CVI was significantly lower in hypertensives both for the septum (- 16.3 +/- 22.8 vs 34.7 +/- 15.3%; p < 0.001) and for the posterior wall (- 15.2 +/- 23.6 vs 38.2 +/- 15.4%; p < 0.001). A significant negative correlation was found between logUAE and the CVI of the septum (r = -0.42; p < 0.001), between the PP and the CVI of the septum (r = -0.40; p < 0.002) and between the CVI and the LVM (r = -0.38; p < 0.001). Multiple regression analysis having as dependent variable the CVI at septum level showed as significantly related independent variables: PP (p < 0.01), logUAE (p < 0.001), and LVM (p < 0.05) (multiple R: 0.76, squared multiple R: 0.57; p < 0.001). It was found that LVM, logUAE, and PP are all correlated with textural parameters, and the CVI can be considered a sensitive parameter in the identification of an abnormal myocardial texture in hypertension. A high level of arterial stiffness and the presence of vascular dysfunction in essential hypertension could participate in the determination of myocardial alterations and permit the identification of patients with the worst prognosis in terms of morbidity or mortality due to cardiovascular events.