الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
 |  | from | 16 |  |  |
| | | from | 16 | | |
Abstract
OBJECTIVE: QT is considered as an index of repolarization. Prolonged QT indicates a myocardium at risk for ventricular arrhythmia .This study aimed to study the repolarization patterns in pediatric patients with cyanotic and acyanotic congenital heart diseases (CHDs).
Methods: This cross-sectional case-controlled study included 100 pediatric patients (males and females); 50 patients with acyanotic CHDs and 50 patients with cyanotic CHDs who presented to Catheterization unit of Cairo University Pediatric Hospital between March 2013 and June 2014 and 50 pediatric healthy children as control. For all the patients’ oxygen saturation measurement, echocardiography and 12 leads electrocardiogram (ECG) done and the corrected QT (QTc) measured .
Results: mean of QTc was higher in acyanotic CHDs with volume overload than control(0.426 s vs 0.4 s, P = 0.009) while in acyanotic with pressure overload(0.409 s vs 0.4 ,p=0.6) in cyanotic hrt diseases with increased and decreasd pulmonary bood flow; it was(0.407 s p= 0.9 and 0.41 s p=0.5 respectively) .
Increasing left ventricular end diastolic dimension (LVEDD) is a risk factor of QTc prolongation (p=0.01) while pulmonary hypertension is not a risk factor of prolongation of QTc(p=0.24).Early repolarization is higher in CHDs(18% in acyanotic patient p=0.003 and 48% in cyanotic patients p=0.0004 and 6% in control) and decreasing oxygen saturation is a risk factor(p=0.01).
Conclusion: prolonged QT is higher in CHDs especially acyanotic with volume overload. Early repolarization affecting mainly patients with cyanotic CHDs and decreasing oxygen saturation is a risk factor.