Prognostic value of cardiac troponin I and left ventricular geometry in pediatric chronic hemodialysis: a one year follow up study

ABSTRACT

Increase in left ventricular mass index [LVMI] is associated with an increase in the incident risk of fatal and nonfatal cardiovascular events in chronic renal failure [CRF]. Cardiac troponin I [cTnl] has been shown to be specific for myocardial damage in chronic dialysis patients. To assess LVMI and cTnI in pediatric patients with CRF on chronic hemodialysis [HD] and to determine their relation to dialytic hypotensive episodes as well as mortality over a period of one year. A prospective follow up study was conducted on 30 pediatric patients with CRF on chronic regular HD with a mean age [10.3 +/- 3.04 years]. Cases were subjected to clinical evaluation, 2-D, M-mode, pulsed and color Doppler echocardiography. Calculation of left ventricular mass [LVM] and LVMI were done. Assessment of cTnI using one-step serum immunoassay test was performed. Cases were clinically followed up for 1 year for dialytic hypotensive episodes and mortality. LVMI was increased in 20 cases [66.7%]. Concentric hypertrophy was present in 13 patients and eccentric hypertrophy was detected in 7 patients. Another six cases had concentric remodeling. All cases were negative for cTnl. There was a statistically significant difference between CRF patients with LVH and those with normal LVM as regards pH, HCO3 and left ventricular posterior wall thickness [LVPW] [p<0.05]. A positive correlation markedly approaching significance was found between fractional shortening [FS] and body mass index [BMI] [r=0.35. p=0.05]. Mortality was 10% and hypotensive episodes occurred in 13.3% of the cases. The positive predictive value of LVMI to mortality was 28.6%, negative predictive value 95.7% with 81.5% specificity and 66.7 +/- sensitivity. Low FS was an excellent predictor of mortality in the studied cases with positive predictive value 100 +/- , and negative predictive value 96.4% with 100% specificity and 66.7% sensitivity. Normal cardiac Troponin I does not preclude cardiovascular risk in chronic hemodialysis patients. Increased LVMI and low FS are useful predictors of mortality in chronic pediatric hemodialysis patients