Ultrasound myocardial tissue characterization by integrated backscatter inchildren treated with anthracyclines

The objective of our study was to evaluate integrated backscatter (IBS) mea surement, an ultrasound method of myocardial tissue characterization, in ch ildren receiving cardiotoxic anthracyclines for malignancy. Myocardial inju ry is known to diminish the normal cyclic variation of IBS (CVIBS) during t he cardiac cycle. We used a cross-sectional, case-controlled study of child ren receiving anthracyclines and serial, prospective observation in a subgr oup of children. The study took place in a university-affiliated, tertiary referral center for pediatric cardiology and oncology. Children undergoing routine echocardiograms before, during, and after anthracycline treatment p articipated in this study, Children evaluated in the cardiology clinic for innocent murmurs participated as controls. There was no intervention. CVIBS was measured using specialized echocardiographic software which quantitate s the intensity of backscattered echoes returning from myocardial cells wit hin a user-defined region of interest. Standard echocardiographic measures of left ventricular function were also made. The results indicated that abn ormal CVIBS was prevalent during anthracycline treatment (17%) and at late follow-up (20%). In serial studies, CVIBS decreased in all children after a nthracycline treatment. Anthracycline dose and time since last dose did not predict which children would have abnormalities of left ventricular functi on or of CVIBS, This report provides preliminary evidence that CVIBS may be a useful supplement to the noninvasive, echocardiographic assessment of th e heart during anthracycline treatment in children.