Retroperitoneal hematoma (RPH) is a well-recognised, albeit rare complication of percutaneous transfemoral cardiac catheterization. We describe an unusual case of renal perforation and RPH following transfemoral cardiac catheterization for endomyocardial biopsy. Diagnosis was made based on multidetector computed tomography (MDCT) which clearly depicted active renal hemorrhage in short acquisition time. The case expands the spectrum of possible complications of percutaneous transfemoral cardiac catheterization and illustrates the usefulness MDCT in quickly and adequately detecting RPH.