As part of an EMT shift at an athletic event yesterday, I took vitals on a 45y/o female Pt who had completed the stressful event about 30 minutes prior. She is very fit and experienced in athletic competition. When I was auscultating her BP, I thought that it sounded like she was skipping some heartbeats or had an irregular heart rhythm. I usually take the BP both on the way up and the way down (and estimate HR while I can hear the pulse), and I definitely heard something going on with her heart rhythm. So after the BP I spent a minute or so listening to (well, palpating) her radial pulse, and I felt something that I'd never felt before. Vitals: HR 60 (irreg?), RR 12, BP 128/78 (irreg?) Her pulse pressure was varying over the course of every 6-10 beats or so. Her systolic pressure for most of the beats was 128, but I could feel that some of the beats occasionally were much softer under my palpation. Strange! So I talked with her a bit about it, and her HX showed no cardiac issues. I know that pulse pressure varies over the course of physical exertion and exercise, but up until now I'd only seen smoothly varying pulse pressures that increased with exertion, and returned to normal smoothly over a period of many minutes. See for example this study: circ.ahajournals.org/content/18/2/249.full.pdf I showed her how to take her radial pulse so that she could see if it happened consistently after exercise (or even without exercise...), and asked her to talk about it with her doctor when she saw him/her next. Does anybody know of pathologies or other causes that can result in a pulse pressure varying over the course of just a few heartbeats? EDIT -- While I was palpating her pulse, the rate turned out to be regular, and it was just the varying pulse pressure that made me think it was irregular during the previous auscultation.