Concomitant congenital malformations are an actual problem in pediatrics. Association of tracheobronchial tree anomalies and congenital heart disease (CHD) could be the cause of the patient’s condition deterioration before and after cardiac surgery. We present a clinical case of a patient with multiple malformations with a long-term and poorly corrected broncho-obstructive syndrome, combined with pneumonia and hypoventilation. After surgery for tetralogy of Fallot at 3 months, the boy needed mechanical ventilation for a long time due to bilateral pneumonia complicated by bilateral pneumothorax. At 7 months, a respiratory infection required hospitalization in the intensive care unit. When pneumonia resolved, the boy was discharged home with continued oxygen support using an oxygen concentrator. The reason for the patient’s prolonged respiratory failure could be explained by prolonged hypoventilation due to narrowing of the left main bronchus and consecutive congenital pneumonia, repeated aspirations, and postoperative mechanical ventilation-associated pneumonia with bilateral pneumothorax. At the age of 1 year 3 months in the Department of Thoracic Surgery of St. Vladimir’s biodegradable stent in the left main bronchus was installed. The bronchus lumen was restored. The boy did not need oxygen support, and his physical and motor development indicators improved. Thus, in patients with tetrad of Fallot, a thorough assessment of the condition of the tracheobronchial tree is advisable in order to develop an appropriate treatment plan if needed. The collaboration of specialists in various fields of care for pediatric patients is the basis for a favorable prognosis in terms of the full growth and development of patients with multiple malformations.