Introduction: Lung agenesis is a rare disorder with a variable, but potentially very bad clinical course. It necessitates complex clinical management, especially in life-threatening situations. Case report: We describe a case of a 6-month-old girl with right lung agenesis who required venovenous extracorporeal membrane oxygenation (VV-ECMO) due to pneumonia complicated by exacerbated previously diagnosed left main bronchus stenosis. The stenosis was resolved by endobronchial intervention and X-ray-guided stent insertion, which enabled weaning from ECMO and was aimed at preventing such a life-threatening respiratory failure in the future. Unfortunately, even with the functional stent, the baby died 2 months post-procedure due to unresolvable bronchial spasms. Discussion: Despite high endobronchial stenting-related mortality in children, in cases where no effective pharmacological or surgical alternatives exist, stenting may be safely performed during VV-ECMO support and be a viable option to overcome critical respiratory failure caused by bronchial stenosis.