The MATRIX Score was developed to predict the risk of radial access crossover in patients with acute coronary syndrome (ACS) undergoing invasive management. This tool can inform and assist operators in anticipating and better addressing difficulties related to trans-radial interventions, potentially improving patients’ care.

The MATRIX Score consists of 8 items that are readily available in clinical practice (age, height, smoking status, renal failure, prior CABG, Killip class, STEMI at presentation, and radial expertise). At cut-off of ≥41 points, the Score can identify patients with at least 2-fold higher risk of radial crossover compared with those at lower score.
 
The Score was generated from the largest trial of ACS patients with randomly assigned radial or femoral access site (MATRIX trial, NCT01433627), and externally validated in the second-largest trial (RIVAL trial, NCT01014273) and in one of the largest trials focusing on STEMI (RIFLE-STEACS trial, NCT01420614) with randomized vascular access.

Radial crossover was defined as a failure to either start or complete coronary angiography or intervention via radial access and subsequent crossover to femoral or brachial access.

The MATRIX Score and all related materials are for the exclusive use of health care professionals and are intended as a supportive risk assessment tool which should never replace clinical judgment, physician- patient relationship, or medical advice. Treatment risks and benefits should always be considered in the context of a comprehensive professional clinical assessment, taking into account all available data and treatment options. Physicians and other healthcare providers should always exercise their own clinical judgment for any given situation.