Echocardiographic Evaluation of Left Ventricular Function in Pediatric Patients with Kidney Transplantation

Background: Cardiovascular complications are a major cause of mortality in patients with end stage renal disease.These abnormalities become more important because of improved life span of children after successful kidney transplantation (KT).

Objective: The aim of this study was to evaluate structural and functional abnormalities of the heart in pediatric patients after KT by using both of the echocardiographic parameters and measurement of serum level of N-terminal pro B- type natriuretic peptide (pro- BNP).

Methods: We investigated possible differences in echocardiographic parameters between a population of 20 patients (mean age: 12±3.1 years) after KT for a median time of 2.1 years (range 0.9-3.5) and 30 age-matched healthy controls. Transmitral flow velocities, mitral annular velocities and myocardial performance index (MPI) were determined by pulsed Doppler and tissue Doppler echocardiography. All of patients had blinded serum BNP levels.

Results: LVH was found in 8 (20%) patients. The mean value of MPI of the patients was significantly different from those of the control subjects (0.47±0.09 vs. 0.37 ± 0.02, p<0.001). We found an increased E/e` ratio (10.2±1.6 vs. 7.8± 1.2, p<0.05); lower e´ and s´ velocities [10.8± 2.8 vs. 13± 2.1 (p<0.001); 6.8±1.9 vs. 7.2 ±1 (p<0.001), respectively] in patients indicating systolic and diastolic abnormalities. Abnormally high level of Pro-BNP, as a sensitive biomarker of myocardial dysfunction was found in 20% of the patients and was associated with greater LVMI and MPI. There was a negative correlation between pro- BNP level and s´ wave velocity as a marker of myocardial longitudinal systolic function(r= -0.44).

Conclusion: Subtle abnormalities in systolic and diastolic LV function are present in renal transplanted patients. These findings were confirmed the importance of early detection and initiation of interventions to modify the natural progression of cardiac dysfunction in children with chronic kidney disease and also in renal transplant recipients.