A 14-year-old patient with the complex congenital heart defect of transposition of great arteries, ventricular septal defect and pulmonary stenosis, after the “reparation a l'etage ventriculaire” operation at the age of 3, was admitted to the hospital with critical pulmonary stenosis with a maximal right ventricle-pulmonary artery (RV-PA) gradient of 110 mm Hg. Transcatheter pulmonary valve implantation was performed in a stepwise manner: first, a metal stent LD Max S18–36 was implanted (BIB 22 mm); subsequently a Melody valve was implanted with the 22 mm system and deployed with a high pressure balloon (Mullins X 20 mm, 8 atm). All was done with the access site via the right femoral vein (Figures 1–3). After the procedure, the pulmonary gradient measured invasively dropped to 23 mm Hg. The day after the valve was implanted, the RV-PA gradient was 108–121 (mean 60) mm Hg. The chest X ray showed a compressed valve-stent in the right ventricle outflow tract (RVOT) (Figures 4A and andB).B). The patient was scheduled for surgery. The pulmonary artery with the squeezed valve was removed (Figure 5) and the pulmonary homograft was successfully implanted. Extensive discentric RVOT calcifications may be connected with a risk of early valve compression. A staged procedure, with at least double-stent prestenting and delayed valve implantation, should be considered in this situation. Fig. 1 Pulmonary angiogram – left lateral view; significant pulmonary incompetence and RVOT stenosis Fig. 3 Pulmonary angiogram, left lateral projection, immediate result after prestenting and Melody valve implantation: proper valve expansion, competent valve Fig. 4 The day after implantation. A – Left lateral projection, B – LAO + caudal projection: sqeezed valve-stent by severe calcifications of the anterior wall of the RVOT (arrows) Fig. 5 Explanted compressed Melody valve Fig. 2 Measurement of the size of the RVOT with the balloon – left lateral view; balloon waist marks the landing zone for the bare metal stent prestenting and the valve; the opacity in the part of the balloon located opposite to the posterior waist is ...