Cardiac functions in children with steroid-sensitive nephrotic syndrome.

Background: The aim of the present study was to evaluate the presence of cardiac systolic and diastolic dysfunction in pediatric patients with steroid-sensitive nephrotic syndrome (NS).

Methods: The study population consisted of 19 patients with debut-relapse of NS aged 1-18 years and 30 sex and age-matched healthy controls. Blood and urine samples, two M-mode conventional echocardiograms and tissue Doppler velocity imaging were evaluated in both attack and remission periods.

Results: With regard to conventional pulse wave Doppler (cPWD), steroid-sensitive NS patients (both in debut / relapse and in remission periods) had a higher peak of late diastolic flow velocities (A peak), and patients in debut / relapse had a lower E/A ratio than the control group, indicating diastolic dysfunction (overall P = 0.003 and P = 0.006, respectively). Based on tissue Doppler velocity imaging echocardiography results, patients in debut/relapse had a higher A' and a lower E'/A' ratio (overall P < 0.001 and P = 0.001, respectively). There was also a significant difference in the cPWD E/TDI E' ratio between the patients showing an increased cPWD E/TDI E' ratio in remission periods compared to in debut/relapse periods (P = 0.09). The albumin levels were positively correlated with E'/A' and E/ E' ratio (r = 0.609; P = 0.007, r = 0.472; P = 0.041 respectively).

Conclusions: Systolic cardiac functions are preserved but diastolic functions are affected in steroid-sensitive NS patients both in debut/relapse and in remission periods in a relatively short time. The persistence of left ventricular (LV) dysfunction during the remission period requires special attention during the follow up for early detection of cardiac abnormalities.