Myocardial performance index combining systolic and diastolic myocardial performance in doxorubicin-treated patients and its correlation to conventional echo/Doppler indices.

This study was designed to evaluate the utility of myocardial performance index (MPI) in anthracycline cardiotoxicity. The MPI measures the ratio of total time spent in isovolumic activity (isovolumetric contraction time and isovolumetric relaxation time) to the ejection time, thus giving a global index combining systolic and diastolic myocardial performance. In this study, MPI was measured in 35 doxorubicin-treated children (aged 108.5+/-55.31 months, 23 males and 12 females) in sinus rhythm and 32 age-matched controls, and it was compared with conventional Doppler echocardiographic parameters. The isovolumetric contraction time was prolonged (38.37+/-24.43 vs 26.37+/-15.53, p <0.02) and ejection time was shortened (231.91 +/- 28.87 vs 256.21+/-19.55, p<0.001) in doxorubicin-treated patients compared to that in normal children. The isovolumetric relaxation time did not show significant difference between patients and control group (60.11+/-10.92 vs 61.06+/-12.12, p>0.05). MPI was significantly increased in doxorubicin-treated patients compared with that in control groups (0.42+/-0.07 vs 0.34+/-0.06, p<0.001), and significant correlation was observed between MPI and fractional shortening, ejection fraction, and left ventricular end diastolic and end systolic diameters (respectively, r = -0.508, p <0.002; r = -0.532, p<0.001; r = 0.467 p<0.005; r=0.606, p<0.001). Also, a weak correlation was found between MPI and duration of the disease and patient ages (r = 0.393, p < 0.02; r = 0.379; p < 0.02). However, there was no correlation between MPI and cumulative doxorubicin dose (r = 0.311, p > 0.05) and diastolic Doppler parameters in doxorubicin-treated patients. We think that MPI may be a useful parameter in monitoring left ventricular dysfunction in anthracyline-treated patients.

High prevelance of chronic magnesium deficiency in T cell lymphoblastic leukemia and chronic zinc deficiency in children with acute lymphoblastic leukemia and malignant lymphoma.

Magnesium and zinc are the elements having essential roles in regulation of cell growth, division and differentiation. There have been some studies in the literature suggesting an association between the deficiency of these elements and the development of malignant disorders. In this study hair and serum zinc and magnesium levels were investigated in children with acute lymphoblastic leukemia (ALL) and malignant lymphoma (ML) at the time of initial diagnosis. Ten children with T-cell ALL, 10 children with B-precursor ALL, 5 children with Burkitt's Lymphoma (BL), 11 children with Hodgkin's lymphoma (HL), 10 children with non-Burkitt non-Hodgkin's lymphoma (NBNHL) and 12 age and sex matched healthy children as a control group were included in the study. Mean hair magnesium levels in all of the groups of the patients were lower than the levels in the control group but the difference was statistically significant only in the children with T cell ALL comparable to the controls (28.9+/-3.9 microg/g and 87.6+/-18.5 microg/g respectiveley, p<0,05). Mean serum magnesium levels in all the cohorts were not significantly different than those in controls (p>0.05 in each comparison). Mean hair zinc levels in the patients with T-cell, B-precursor ALL, BL, HL, NBNHL were 103.4+/-14.6 microg/g, 100.9+/-7.8 microg/g, 91.1+/-19 microg/g, 72.5+/-9.1 microg/g, 103.2+/-12.2 microg/g respectively. Each of these levels were significantly lower than the mean hair zinc levels of the control group (141.2+/-9.6 microg/g, p<0.05 in each comparison). Although mean serum zinc levels in all of the groups were also decreased, the differences were statistically significant only in the groups with B-precursor ALL, HL and NBNHL (75.9+/-5.29 microg/dl, 68.6+/-7.3 microg/dl, 85.7+/-5.5 microg/dl respectively) when compared with controls (105.1+/-9.9 microg/dl, p<0.05 in each comparison). Hair magnesium and zinc levels showed a positive correlation with each other in all the groups (r congruent with 0.5). No significant difference was found in the mean hair/serum magnesium and zinc levels between malnourished and nonmalnourished patients. In conclusion, regarding the results of our study and previous data in the literature chronic magnesium and zinc deficiency seems to be associated with the development of ALL and malignant lymphoma in a group of patients.