Post-cardiac injury syndrome (PCIS) is a syndrome characterized by pericardial and/or pleural effusion, triggered by a cardiac injury, usually a myocardial infarction or cardiac surgery, rarely a minor cardiovascular percutaneous procedure. Nowadays, the post-cardiac injury syndrome, is regaining importance and interest as an emerging cause of pericarditis, especially in developed countries, due to a great and continuous increase in the number and complexity of percutaneous cardiologic procedures. The etiopathogenesis seems mediated by the immunitary system producing immune complexes, which deposit in the pericardium and pleura and trigger an inflammatory response. We present the atypical case of a 76-year-old man presenting with a hydro-pneumothorax, low-grade fever and elevated inflammation markers, after two complex percutaneous coronary interventions, executed 30 and 75 days prior. The clinical features of our case are consistent with the diagnostic criteria of PCIS: prior injury of the pericardium and/or myocardium, fever, leucocytosis, elevated inflammatory markers, remarkable steroid responsiveness and latency period. Only one element does not fit with this diagnosis and does not find any further explanation: the air accompanying the pleural effusion, determining a hydro-pneumothorax and requiring a pleural drainage catheter positioning.