MRI measurements Representative blood oxygen saturation (SbO 2 ) maps and left ventricle (LV) geometry images from a control participant and a patient with heart failure, demonstrating reduced coronary sinus SbO 2 and impaired LV contractility in the patient. The colour scale indicates SbO 2 of 20 to 100%. (Courtesy: Ting Huang et al. Sci. Trans. Med. 18 eady6269 (2026))" title="Click to open image in popup" href="https://physicsworld.com/wp-content/uploads/2026/05/11-05-26-cardiac-mri-figure4b.jpg"> MRI measurements Representative blood oxygen saturation (SbO 2 ) maps and left ventricle (LV) geometry images from a control participant and a patient with heart failure, demonstrating reduced coronary sinus SbO 2 and impaired LV contractility in the patient. The colour scale indicates SbO 2 of 20 to 100%. (Courtesy: Ting Huang et al. Sci. Trans. Med. 18 eady6269 (2026))

The amount of oxygen that a heart consumes is a key indicator of its health.…