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 hy pertrophy (LVH) which alters the ventricular geometry. The videodensitometr ic textural ultrasonic analysis of hypertensive myocardium has provided evi dence of impairment in the cyclic variation of the mean gray level. This mi ght be considered as an index of intrinsic myocardial function. Objectives: The aim of the present study was to analyse the connection betw een the midwall fractional shortening and end-systolic stress. The ultrason ic textural parameters in hypertensive patients, arranged in different grou ps according to the level of LVH and relative wall thickness, were also eva luated. Methods: A group of age-matched (58 +/- 7 years) male essential hypertensiv e patients (n = 70) were compared to a group of normotensive and healthy su bjects used as controls (n = 32). All subjects performed a conventional 2D- Doppler echocardiography to analyse the left ventricular performance. A qua ntitative analysis of the echocardiographic digitised imaging was also carr ied out with the help of a calibrated digitisation system in order to calcu late 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 hype rtensive patients showed a significantly lower midwall fractional shortenin g than the control patients. The CVI was also significantly lower in the hy pertensives 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 variab les and the end-systolic stress. Conclusion:The CVI was found to be a highly sensitive parameter in the iden tification of abnormal echodensity in essential hypertension. The CVI was s ignificantly lower in patients with concentric hypertrophy in comparison wi th other left ventricular geometric models. This parameter could be conside red as an index of the intrinsic myocardial function, being related, in ess ential hypertension, to midwall fractional shortening and to end-systolic s tress.