Supplementary Material for: Two-Step Distal Radial Artery Cannulation for Challenging Radial Anatomies

The radial artery is the preferred access site for cardiac catheterization because of patient comfort, early ambulation, and improved survival in acute coronary syndromes, when compared to the femoral artery route. However, it is associated with a high radial artery occlusion (RAO) rate, and patent haemostasis which can reduce this is extremely hard to implement in a busy clinical practice. Smaller sized sheaths are associated with less RAO but are uncommonly used as they could limit procedural prowess and complexity. Alternatively, the distal radial artery (dRA) approach appears to be safer with observed RAO rates of well under 1 percent without compromising benefits offered by the radial artery access. Default dRA can be accessed by palpation alone in most cases with some practice, and this can be improved further with ultrasound guidance. There is a subset of patients, especially in the elderly, where dRA access can be particularly challenging. To mitigate this, we propose a two-step cannulation strategy and illustrate this with a few cases with difficult dRA and radial artery anatomies.