Ultrasonic myocardial textural parameters and midwall left ventricular mechanics in essential arterial hypertension

Background: The evaluation of the systolic left ventricular performance in hypertensive patients presents some problems related to left ventricular hypertrophy (LVH) which alters the ventricular geometry. The videodensitometric textural ultrasonic analysis of hypertensive myocardium has provided evidence of impairment in the cyclic variation of the mean gray level. This might be considered as an index of intrinsic myocardial function. Objectives: The aim of the present study was to analyse the connection between the midwall fractional shortening and end-systolic stress. The ultrasonic textural parameters in hypertensive patients, arranged in different groups according to the level of LVH and relative wall thickness, were also evaluated. Methods: A group of age-matched (58 +/- 7 years) male essential hypertensive patients (n = 70) were compared to a group of normotensive and healthy subjects used as controls (n = 32). All subjects performed a conventional 2D-Doppler echocardiography to analyse the left ventricular performance. A quantitative analysis of the echocardiographic digitised imaging was also carried out with the help of a calibrated digitisation system in order to calculate the septum and the posterior wall textural parameters. The myocardial mean gray level was calculated to derive the cyclic variation index (CVI). Results: When subjected to a higher meridional endsystolic stress, the hypertensive patients showed a significantly lower midwall fractional shortening than the control patients. The CVI was also significantly lower in the hypertensives group, both for the septum wall (-16.3 +/- 22.8 vs 34.7 +/- 15.3%; P < 0.001) and the posterior wall (-5.2 +/- 23.6 vs 38.2 +/- 15.4%; P < 0.001). A significant correlation was found between the midwall fractional shortening (MFS) and the textural parameters, and between these two variables and the end-systolic stress. Conclusion:The CVI was found to be a highly sensitive parameter in the identification of abnormal echodensity in essential hypertension. The CVI was significantly lower in patients with concentric hypertrophy in comparison with other left ventricular geometric models. This parameter could be considered as an index of the intrinsic myocardial function, being related, in essential hypertension, to midwall fractional shortening and to end-systolic stress.