Vascular function and circulating progenitor cells in thromboangitis obliterans (Buerger's disease) and atherosclerosis obliterans.

Thromboangitis obliterans (TAO; Buerger's disease) and atherosclerosis obliterans (ASO) are associated with endothelial dysfunction. The purpose of this study was to evaluate the role of circulating progenitor cells (CPCs) in endothelial function in patients with TAO and ASO. We measured flow-mediated vasodilation (FMD), nitroglycerine-induced vasodilation, and circulating CPCs in 30 patients with TAO and 30 age- and sex-matched healthy subjects and in 40 patients with ASO. FMD was smaller in both the TAO group and ASO group than in the control group (6.6 ± 2.7%, 5.7 ± 3.3% versus 9.5 ± 3.1%, P<0.0001, respectively). There was no significant difference in FMD between the TAO group and ASO group. Nitroglycerine-induced vasodilation was similar in the 3 groups. The number of and migration of circulating CPCs were similar in the TAO group and control group, whereas the number of and migration of circulating CPCs were significantly lower in the ASO group than in other groups (ASO 553 ± 297/mL versus TAO 963 ± 543/mL; control 1063 ± 426/mL and ASO 36 ± 18/hpf versus TAO 62 ± 23/hpf; control 68 ± 18/hpf, P<0.0001, respectively). There was a significant relationship between the number of and migration of CPCs and FMD (r = 0.43 and r = 0.40, P<0.0001, respectively). FMD was impaired in patients with TAO as well as in patients with ASO compared to that in normal control subjects, and the number of and function of circulating CPCs were not decreased in patients with TAO. These findings may partially explain why there are differences in cardiovascular morbidity and mortality rates between patients with TAO and patients with ASO.