Itamar Medical's Endo-PAT2000 is an FDA-cleared device used to assess endothelial function.
Endo-PAT2000 was used in a clinical study (Vaclavik et al. Indoor Particles Affect Vascular Function in the Aged. American Journal of Respiratory and Critical Care Medicine 2008; Vol 177. pp. 419-425) for evaluating the effect of high-efficiency particulate air (HEPA) filters on endothelial function, an indicator of cardiovascular health.
Both short-term and long-term exposure to ambient levels of particulate are associated with increased fatalities related to respiratory and cardiovascular disease. Researchers in the study believe endothelial dysfunction, which is a strong predictor of adverse cardiovascular conditions, may be the source of this increase in respiratory and cardiovascular diseases.