Aim: Absent pulmonary valve syndrome (APVS) is found in 3-6% of patients with Tetralogy of Fallot (TOF). Along with findings of TOF. absence of pulmonary valve tissue results in aneurysmal dilatation of the main and branch pulmonary arteries compressing the trachea. main-stem. https://www.danishhospitalconstruction.com/product-category/acoustic-guitar-strings/