Commentaries on Viewpoint: The human cutaneous circulation as a model of generalized microvascular function

TO THE EDITOR: The paper by Holowatz et al. (3) may be advancing our ability to achieve the elusive goal of using readily accessible vessels, such as in the skin, as diagnostic surrogates for the vessels supplying internal organs (especially the heart and brain). This advance would allow minimally invasive detection of early, presymptomatic disease of the arteries in the critical organs. The new technique applied by them advances the ability to monitor skin microcirculation, but it is not clear that they have demonstrated that skin circulation is quantitatively representative of the vessels supplying critical internal organs in that same individual. For example, Aboyans et al. (1) recently reconfirmed that large and small vessels do show similarities as far as atherosclerosis is concerned, but Haltmayer et al. (2) showed clearly that different vessel beds respond differently to the same risk factors. The skin circulation consists predominantly of microvessels, which raises the question as to their propensity for being affected by atherosclerosis (or other systemic diseases such as hypertension or diabetes mellitus) just like the microvessels of the critical organs or, perhaps better still, the larger, conduit vessels that most often result in massive infarctions due to their blockage. Hence, the onus is on the authors to use their technique to show that indeed they can apply it to skin microvessels as indicators of disease in vessels of the internal organs in the same individual.