Myocardial ultrasound tissue characterization in patients with chronic renal failure.

The objective of this study was to detect ultrastructural changes in myocardium related to collagen content by ultrasound tissue characterization in patients with chronic kidney disease (CKD) and in uncomplicated hypertensive control subjects. In 25 hemodialysis (HD) patients, in 25 patients with moderate to severe chronic renal failure (CRF), and in 10 patients with essential hypertension (EH) and normal renal function matched for age, BP, and left ventricular mass index, left ventricular anatomy and function were evaluated by conventional echocardiography, and integrated backscatter signal (IBS) was analyzed by acoustic densitometry. IBS mean reflectivity increased from 48% in patients with EH to 56% in patients with CRF to 62% in HD patients (ANOVA P < 0.01). IBS mean cyclic variation was progressively increased from 4.35 +/- 1.2 dB in HD patients to 5.27 +/- 0.90 in patients with CRF to 6.50 +/- 1.6 dB in patients with EH (ANOVA P < 0.01). At multivariate analysis, IBS mean reflectivity was positively related to age and serum creatinine (beta 0.351, P = 0.036; and beta = 0.408, P = 0.016, respectively). IBS mean cyclic variation was inversely related to age and serum creatinine (beta = -0.274, P = 0.025; and beta = -0.262, P = 0.025, respectively) and positively related to left ventricular midwall fractional shortening and transmitral E/A ratio (beta = 0.269, P < 0.05; and beta = 0.314, P < 0.001, respectively). The data support the hypothesis that interstitial collagen deposition may appear early in the course of CKD and suggest that acoustic densitometry may represent a useful tool for the assessment of myocardial tissue changes in patients with CKD.