Study will compare measurements made with Necklace device for stroke volume/cardiac output with values from a FDA-approved reference device. The gold standard that will be used is Cardiac MRI. Subjects will be measured with both the Necklace, reference device, and the Cardiac MRI. Values calculated by the Cardiac MRI analysis will be compared with the reference device and the Necklace.~The Cardiac MRI will be received ~1-4 days after the measurement is completed. The data will be compared with data collected from the Necklace and the reference device during the study.
Study will compare measurements made with Necklace device for stroke volume/cardiac output with values from a FDA-approved reference device. The gold standard that will be used is Cardiac MRI. Subjects will be measured with both the Necklace, reference device, and the Cardiac MRI. Values calculated by the Cardiac MRI analysis will be compared with the reference device and the Necklace.