Scintigraphy of the cardiovascular system in children is less common than in adults, reflecting the different nature and prevalence of cardiac diseases in paediatrics. Congenital malformations of the heart and their effect on cardiac and pulmonary functions and on myocardial perfusion are common indications in children. The first pass study is an investigation that can detect and quantify cardiac left-to-right shunts. It is used only in selected cases. Myocardial perfusion scintigraphy (MPS), with or without physical or pharmacological stress, provides important information on blood supply to the myocardium. It can also evaluate myocardial contractility with gated SPECT. The gated cardiac blood pool scan, also known as radionuclide ventriculography or multigated acquisition (MUGA) scan assesses the cardiac blood pool synchronized to the child’s ECG and allows measurement of the left ventricular (LV) ejection fraction (EF). In most centres, this study has been replaced in the last decade by echocardiography and MRI to assess the quality of the ventricular contraction and is therefore not discussed further in this chapter (Milanesi et al., Semin Nucl Med 47(2): 158–169, 2017; Venet et al., Front Pediatr 10: 909994, 2022). Vascular anomalies in children include benign tumors such as infantile hemangiomas and hemangioendotheliomas as well as low and high-flow vascular malformations. Whole-body blood pool scintigraphy with focused SPECT or SPECT/CT provides specific diagnosis for vascular anomalies and is commonly used in conjunction with radiological imaging methods, especially when those are inconclusive.
