Assessment of Left Ventricular Function with Echocardiography in Patients Treated with Adriamycin: A Load-Independent Index of Myocardial Contractility and Comparisons between Rest and Exercise

ABSTRACT

PURPOSE: The aim of this study was to evaluate myocardial injury in children treated with adriamycin by echocardiography, which is non-invasive and safe measurement for children. METHODS: Left ventricular dimensions, wall stress, and contractile function were determined by echocardiographic methods in 17 patient recepients with adriamycin chemotherapy at rest(group 1) and during stress(group 2). Twenty age-matched normal subjects were established as control group. RESULTS: End-diastolic dimension was decreased in both groups(group 1; 92+/-7% of normal, group 2; 87+/-8% of normal, P<0.05). Left ventricular end diastolic volume and wall mass were also decreased in both groups(group 1; 96+/-12 mL/m2 and 145+/-18 g/m2, group 2; 87+/-8 mL/m2 and 137+/-16 g/m2, respectively, P<0.05 and P<0.05) and group 2 showed lower values than group 1. Meridional end systolic stress(ESSm) was increased in both groups but there was no significant difference between the two groups(group 1; 52.6+/-6.2 g/cm2, group 2; 63.5+/-8.5 g/cm2, P<0.05, normal value 45.7+/-3.5 g/cm2). The load-independent relation of rate-corrected circumferential fiber shortening velocity(Vcfc) to ESSm has a significant abnormal change in 7 out of 17(41%) in group 1 and 12 out of 17(71%) in group 2. CONCLUSION: The load-dependent systolic index, such as fractional shortening, may fail to show abnormality because of the compensatory changes in preload and afterload which can mask the impaired contractility. Therefore, systolic performance also should be monitored by a load-indepedent contractility index such as slope value of the end-systolic pressure-dimension relation and the position of the left ventricular stress-fiber shortening velocity after exercise.