Sonographic Diagnosis and Anatomic Mapping of a Radial Artery Pseudoaneurysm Following Transradial Cardiac Catheterization.

Radial artery pseudoaneurysm is a rare complication of transradial catheterization. We report a 74-year-old woman on rivaroxaban who developed a pulsatile distal forearm mass 1 day after transradial cardiac catheterization. High-frequency ultrasound showed a rounded extra-arterial lesion (7.6 × 8.9 × 7.0 mm) not involving all wall layers, with thrombus, a discrete communicating neck, turbulent bidirectional "yin-yang" color Doppler, and preserved distal flow. Anatomic mapping showed the lesion abutting adjacent tendons and the palmar cutaneous branch of the median nerve. Surgical excision and microscopic repair succeeded. Sonographic characterization provided anatomic detail that, with clinical and surgical assessment, informed individualized management.