Analysis of transmural trends in myocardial integrated backscatter in patients with progressive systemic sclerosis.

Cardiac involvement in progressive systemic sclerosis (PSS) is common and has a strong negative impact on the prognosis, especially when autoantibodies are present. To determine whether ultrasonic tissue characterization can detect early ultrastructural changes in the sclerodermal myocardium, we analyzed the transmural heterogeneity in myocardial integrated backscatter (THIB). "A-THIB" was defined as the absolute difference in integrated backscatter between the left (subendocardial) and right (subepicardial) ventricular halves of the myocardium in the septum and posterior wall, and was measured in 11 patients with PSS and 10 age- and sex-matched healthy participants. A-THIB in patients with PSS was higher than that in healthy participants (1.3 +/- 1.3 vs 4.0 +/- 1.4 dB for the septum and 1.1 +/- 0.7 dB vs 2.8 +/- 0.4 dB for the posterior wall; mean +/- SD, respectively, P <.0005). Septal A-THIB was higher in patients with PSS with than without anti-Scl70 or antinucleolar antibodies (3.2 +/- 1.1 vs 5.0 +/- 1.0 dB, P =.0165). Early changes in the myocardium of patients with PSS, possibly related to increased interstitial collagen deposition, can be detected by quantitative analysis of THIB.