Left ventricular diastolic filling patterns associated with progressive anthracycline-induced myocardial damage: A prospective study.

The objective of this study was to examine changes in diastolic function associated with progressive myocardial damage and their implications. We used prospective sequential Doppler echocardiographic studies of left ventricular (LV) function. The study included 125 consecutive children (median age 6.3 years) receiving anthracyclines to cumulative doses between 45 and 1150 mg/m2 (median 270 mg/m2). We measured peak early (E) and atrial (A) phase filling velocities, EA ratio, deceleration and isovolumic relaxation times (EDecT and IVRT), heart rate, and fractional shortening (SF). Results were compared serially and with individually paired control data matched for body surface area. Progressive myocardial damage was evidenced by a mean SF decrease of 1 absolute %/100 mg/m2 of anthracycline. Six patients developed cardiac failure. After 1-100 mg/m2 of anthracyclines, the EA ratio decreased (mean 1.54-1.40, p = 0.02) and IVRT became prolonged (54 vs 52 msec in controls, p = 0.03). EA ratio increased again with the next dose, usually normalizing thereafter. Twelve patients ended treatment with an EA ratio <1 (1 cardiac death) and 17 with EA ratio >2 (2 cardiac deaths). Diastolic abnormalities were not strongly predictive of reduced SF. Modest changes in left ventricular diastolic filling patterns occur during anthracycline treatment of childhood malignancies. Although 20% of patients have significant abnormalities of diastolic filling by the end of treatment, considerable individual variability renders the pathophysiological and clinical implications of the early changes uncertain.