The Endopath device performs a 15-minute arterial stress test, including a 5-minute brachial artery occlusion, to assess endothelial function and nitric oxide response.

“I have a device called the EndoPAT that is basically like a stress test for the arteries. It's a test that you administer uh for over about 15-minute period. 5 minutes of it is an occlusion of your brachial artery. So, you have a blood pressure cuff on, and you pump it up higher than your systolic blood pressure. You'll get like a pins and needles sensation as you kind of cut off the flow to their hand for a minute. Yeah, it's kind of a weird sensation, but after 5 minutes, you crank open the um the blood pressure cuff, blood rushes back down into the hand, and if you have healthy endothelial glycocalyx and a healthy endothelium, that huge slug of blood is registered as, "Oh, here it comes." The body will pump out nitric oxide to cause the smooth muscle in the artery to relax, and then the flow improves.”