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BACKGROUND: Myocardial performance index (MPI) or Tei index is a Doppler-derived index of combined systolic and diastolic myocardial function, calculated as the sum of isovolumetric relaxation time (IRT) and isovolumetric contraction time (ICT) divided by the ejection time (ET). OBJECTIVE: To evaluate the right and left ventricular systolic and diastolic function using MPI in children before and after liver transplantation. METHODS: A cross-sectional study was conducted on 30 children with liver cirrhosis before liver transplantation, 30 age-matched comparison group at least 6 months after liver transplantation, and 30 aged-matched children without history of heart disease in Nemazi Liver Transplant Center, Shiraz, Iran, from April 2012 to April 2014. Echocardiographic evaluation was carried out with a GE Vivid 3 echocardiographic machine, using a 3-MHz probe with tissue Doppler imaging (TDI) software using conventional and TDI method. RESULTS: The mean±SD left ventricle Tei index in patients was 0.33±0.02 before liver transplantation, 0.34±0.02 after liver transplantation, and 0.33±003 in the comparison group (p=0.36). The mean±SD right ventricular Tei index was 0.35±0.04 in patients before transplantation, 0.36±0.46 after liver transplantation, and 0.28±0.04 in the comparison group (p<0.001). In addition, when TDI was used, the mean±SD left ventricular Tei index was 0.39±0.50 in patients before transplantation, 0.37±0.42 after liver transplantation, and 0.38±006 in the comparison group (p=0.32). The tissue Doppler-derived Tei index for the right ventricle was 0.37±0.04 in patients before transplantation, 0.37±0.04 after liver transplantation, and 0.33±0.05 in the comparison group (p=0.031). The left ventricular Doppler-derived Tei index had a significant (p=0.03) correlation with Child-Turcotte-Pugh (CTP) score (r=0.57). CONCLUSION: Left ventricular MPI with Doppler echocardiography was correlated with CTP score. Right ventricular MPI was significantly increased in patients with cirrhosis and did not improve 6 months after transplantation.
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BACKGROUND: Anthracyclines are important components of many chemotherapeutic protocols. The present study aimed to evaluate the repolarization changes in electrocardiography (ECG) which may predict drug induced arrhythmia. MATERIALS AND METHODS: In this cross-sectional study, the recorded ECGs were assessed for QT dispersion (QTd), QT corrected dispersion (QTcd), T peak to Tend dispersion (TPed), and P dispersion (Pd) in 12 ECG leads. The demographic information, including sex, age, and duration of drug consumption, were recorded, as well. RESULTS: In this study, 112 patients, including 58 females (52%) and 54 males (48%) with the mean age of 8.7±4.5 years, as the case group were compared with 43 children, including 17 males (40%) and 26 females (60%), in the control group. Most of our patients (88%) had received usual doses of anthracyclines; i.e., 330 mg/m2. QT dispersion of the patients and the controls was 0.054±0.02 and 0.05± 0.02 seconds, respectively. No significant difference was found between the patients and the controls regarding corrected QT dispersion (P> 0.05). However, P dispersion time had increased in the patients' group. Our study showed that the duration of anthracyclines therapy did not cause any significant increase in ventricular re-polarization parameters. CONCLUSION: Anthracyclines may show their cardiac toxicity through increasing P dispersion.
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BACKGROUND: Chronic renal failure and hemodialysis affect many ECG parameters which can affect cardiac repolarization. OBJECTIVE: To investigate the change in ventricular repolarization before and after kidney transplantation in children. METHODS: A total of 45 children with end-stage renal disease, 45 children at least 6 months after successful renal transplantation, and 45 normal age-matched subjects were enrolled into this study. A 12-lead ECG was recorded in the 3 groups. QT dispersion, QTc dispersion, and T peak to T end (TPE) dispersion were measured. RESULTS: In the patients before and after renal transplantation and the normal children, respectively, the mean±SD QT dispersion was 0.083±0.033, 0.056±0.029, and 0.033±0.016 (p<0.01); the mean±SD QTc dispersion was 0.104±0.038, 0.066±0.033, and 0.039±0.020 (p<0.01); the mean±SD TPE interval dispersion was 0.060±0.021, 0.045±0.021, and 0.034±0.019 (p<0.01). There was a significant correlation between left intra-ventricular diastolic diameter and QT dispersion, QTc dispersion, and TPE dispersion. The systolic velocity of the mitral valve also correlated with TPE dispersion (r=0.44, p=0.01). CONCLUSION: In children with chronic renal failure, indices of ventricular repolarization improve after transplantation, though they still remain longer than the normal values.
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BACKGROUND: Measurement of central venous pressure (CVP) is a reliable method for evaluating intravascular volume status and cardiac function; however it is an invasive and expensive method that may result in some complications such as arterial puncture, pneumothorax and development of infections. This study was performedto compare CVP measurements between central and peripheral catheters in infant and children with congenital heart disease. METHODS: The CVP and peripheral venous pressure (PVP) were measured simultaneously in 30 patients within 10 consecutive hours. RESULTS: The mean difference between CVP and PVP was 1.48±0.98 mmHg. The linear regression equation showed that CVP was 0.374+0.774 PVP (r(2) = 0.725). CONCLUSION: PVP measured from a peripheral intravenous catheter in infants and children with congenital heart disease is an accurate estimation of CVP and its changes has good concordance with CVP over a long period of time.
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Central venous pressure (CVP) measurement is a reliable method for evaluating intravascular volume status and cardiac function, but it is an invasive method that results in some complications such as arterial puncture, pneumothorax, and development of infection. The current study was performed to compare CVP measurements between central and peripheral catheters in infants and children with congenital heart disease referred for right-sided heart catheterization. The CVP and peripheral venous pressure (PVP) in 45 patients were measured simultaneously. The mean difference between CVPs measured from the central and peripheral catheters was 8 +/- 4 cm H(2)O. The linear regression equation showed that CVP = 0.32 PVP + 3.8 (r = 0.67; p < 0.005). There was no difference in CVP measurements depending on the intravenous cannula and chest diameters, arm diameter, arm length, body surface area, patient's age (< or =10 years and >10 years), and type of congenital heart disease (cyanotic or noncyanotic). In conclusion, although CVP measured from a peripheral intravenous catheter in infants and children with congenital heart disease is not as accurate as the measurement in adults, the aforementioned linear regression equation based on measurement of PVP gives a reliable estimate of CVP.