Objectives Our goal was to validate an educational 90-min minicourse in lower-irradiating cardiac invasive techniques. Background Despite comprehensive radiation safety programs, patient radiation exposure in invasive cardiology remains considerable. Methods Before and at a median period of 3.7 months after the minicourse at 32 German cardiac centers, 177 interventionalists consistently documented radiation parameters for 10 coronary angiographies: dose area product (DAP), radiographic and fluoroscopic fractions, fluoroscopy time, and number of radiographic frames and runs. Results A total of 154 cardiologists attended the minicourse and achieved significant (p < 0.001) decrease in patients' median overall DAP (-48.4%), from baseline 26.5 to 13.7 Gy x cm(2). They reduced fluoroscopy times (-20.8%), radiographic runs (-9.1%), frames/run (-18.6%) and frames (-29.6%), and both radiographic DAP/frame (-27.4%) and fluoroscopic DAP/s (-39.3%), which indicate improved collimation, reduced-irradiation angulations, or adequate image quality. Dose-related parameters for the remaining 23 invited cardiologists unable to attend the workshop did not change significantly in univariate comparison. Multilevel analysis (p < 0.001) confirmed the efficacy of the minicourse itself (-14.7 Gy x cm(2)) and revealed higher DAP for increasing body mass index (+1.5 Gy x cm(2) per kg/m(2)), male sex (+5.8 Gy x cm(2)), age (+1.5 Gy x cm(2)/decade), and-owing to different settings during image acquisition-for advanced flat-panel detector systems (+9.0 Gy x cm(2)) versus older, traditional image intensifier systems. Conclusions Despite significant required training in radiation safety for all interventional cardiologists, the presented additional 90-min minicourse significantly reduced patient dose. (C) 2014 by the American College of Cardiology Foundation