Published online by Cambridge University Press: 21 July 2011
Tetralogy of Fallot is the most common cyanotic congenital heart disease with decreased pulmonary blood flow. Right-to-left shunt and infundibular pulmonary stenosis in this disease lead to a decrease in arterial O2 saturation. Hypoxia is a strong stimulus for angiogenesis; however, the reason for insufficiency in the pulmonary vascular growth in patients despite chronic arterial hypoxia is still not known. This study was planned considering that the impairment in vascular endothelial growth factor-receptor relationship or the vascular endothelial growth factor-receptor deficiency in the pulmonary vascular bed during development may cause insufficiency of pulmonary vascular growth. A total of 24 patients were grouped as cyanotic – including 13 patients with tetralogy of Fallot – and acyanotic – including 11 patients with left-to-right shunt lesions. During cardiac catheterisation, vascular endothelial growth factor measurements were performed; and oxygen saturations, pressures, and haemoglobin levels were measured. Perioperative lung biopsy for vascular endothelial growth factor receptors was performed in the cyanotic group. Vascular endothelial growth factor of the aorta was higher in the acyanotic group. There was a significant negative correlation between vascular endothelial growth factor levels and aortic O2 saturation in the cyanotic group (p < 0.05). Vascular endothelial growth factor tissue staining was negative in 11 out of 13 (84.6%) patients. KDR/Flk-1 receptor was positive in four out of 13 (30.7%) patients; Flt-1 receptor was positive in six out of 13 (46.1%) patients. Vascular endothelial growth factor values were found to be lower than those of the acyanotic patients in this study. Low serum vascular endothelial growth factor levels of the cyanotic group, in spite of the hypoxia, demonstrated the importance of studying vascular endothelial growth factor tissue levels and vascular endothelial growth factor receptors in these patients.