In cases of cyanotic defects, what aspect of growth is mainly affected?

In cases of cyanotic defects, the primary concern is often related to insufficient oxygenation of the blood, which can lead to various systemic effects on the child's growth and development. Among these, growth velocity in both length and weight can be significantly impacted. This occurs because cyanotic conditions can result in inadequate oxygen delivery to tissues, which affects metabolism and energy levels, leading to decreased overall growth.

Children with cyanotic heart defects may experience failure to thrive, which is characterized by suboptimal gain in weight and length for age. This is often due to increased energy expenditure caused by the work of breathing, poor feeding, and the increased metabolic demands of oxygen-poor blood. Thus, both weight and length growth velocity are key indicators of the child’s growth in this clinical context, making them the most affected aspects of growth in cases of cyanotic defects.