Harnessing the parallax for better spatial awareness.

Despite easy access to imaging diagnostic procedures and an abundance of spatial data, most cardiac interventions are still performed under two-dimensional fluoroscopy. Incorporating anatomical data from scans into procedures plans has the potential to improve the swiftness and outcomes of percutaneous cardiac interventions. Therefore, procedure planning based on the specific anatomy is becoming a new standard of excellence in interventional cardiology. Still, we often tend to disregard specific spatial relations and the actual direction of catheter tip movement inside the body, relying on a try and error approach. The precise spatial orientation of instruments and prosthetic devices is crucial, especially during structural heart interventions. Here, we present how deliberate movements of objects under fluoroscopy can reveal the spatial orientation of catheters and other devices. We also propose a novel "two-point rule" for identifying three-dimensional relations between points in space. Understanding and applying this rule might substantially increase the spatial awareness of operators performing cardiovascular interventions. Although the concept is pretty simple, using it "live" during interventional cardiology procedures requires thorough understanding and practice. We propose the "two-point rule" as a crucial rule to develop expertise in spatial orientation under fluoroscopy and ensure high-quality outcomes.