Assessment of right ventricular function and anatomy using peripheral vein infusion of krypton 81m.

A method for imaging the right side of the heart (atrium, ventricle and main pulmonary artery) and for assessment of RV systolic function (ejection fraction and ejection rate) is described. An ultra-short-lived isotope (81Krm) is continuously eluted in 5% dextrose and infused into an ante-cubital arm vein; standard multigated images are acquired using a gamma camera and commercially available software. Preliminary evaluation of the method in 55 subjects (20 with repaired tetralogy of Fallot, 14 with dilated cardiomyopathy and 21 normal volunteers) showed that the technical success rate was 100%; that RV boundaries free from LV overlap can be clearly visualised due to efficient exhalation of 81Krm through the lungs and that 81Krm measurements of RVEF are reproducible. The technique offers considerable potential for serial non-invasive assessment of RV function.