Computed tomography angiography (CTA) has been investigated as a confirmatory study (CS) for the diagnosis of brain death (BD). International consensus regarding its use, study parameters, and evaluation criteria is lacking. In the German BD guideline, a CTA protocol was first introduced in 2015. The authors obtained a comprehensive dataset of all BD examinations in adults from the German organ procurement organization to investigate implementation, results, and impact of CTA on BD determination during the first 4 years. In 5152 patients with clinically absent brain function, 1272 CTA were reported by 676 hospitals. Use of CTA increased from 17.2% of patients in the first year to 29.7% in the final year. CTA replaced other CS such as electroencephalography without increasing overall CS frequency. Technical failure was rare (0.9%); 89.3% of studies were positive. Negative results (9.8%) were more frequent with secondary brain injury, longer duration of the clinical BD syndrome, or unreliable clinical assessment. Median time to diagnosis was longer with CTA (2.6 h) versus other CS (1.6 h). CTA had no differential impact on the rate of confirmed BD and did not improve access of small hospitals to CS for BD determination. CTA expands the range of available CS for the diagnosis of BD in adults. Real-world evidence from a large cohort confirms usability of the German CTA protocol within the guideline-specified context.