Portugal and Spain share one of Europe’s largest border regions, where healthcare accessibility remains a critical challenge. Despite the potential benefits of cross-border cooperation, healthcare planning has largely neglected shared access to specialized medical infrastructure, such as hemodynamic units. This study assesses spatial accessibility to these units for populations in the Portuguese-Spanish border region, particularly those at risk of acute myocardial infarctions. Using a Geographic Information Systems (GIS)-based three-step floating catchment area (3SFCA) method, we analyze healthcare resource distribution and identify disparities in service availability. The results highlight areas with limited access to emergency cardiac care, revealing crucial gaps in infrastructure. Findings suggest that strategic cross-border collaboration could enhance healthcare equity and reduce response times in life-threatening situations. This research provides valuable insights for policymakers, advocating for integrated planning efforts to optimize healthcare accessibility and improve patient outcomes in borderland regions.