A case report of right ventricular compression from a septal haematoma during retrograde coronary intervention to a chronic total occlusion.

Background: Septal haematomas causing left ventricular or biventricular outflow obstruction are rare but known complications of chronic total occlusion (CTO) percutaneous coronary intervention (PCI) and can be life-threatening.

Case Summary: In this case, we describe the formation of a septal haematoma during retrograde CTO PCI. The patient was initially managed conservatively but became progressively unstable, for which she underwent coiling of the inflow and outflow of the septal perforator.