Autonomic functions in Buerger's disease.

One of the pathophysiological features in Buerger's disease, i.e. thromboangitis obliterans (TAO), is vasospastic phenomena. So autonomic reactivity was evaluated in 12 patients of Buerger's disease (1-6 years duration) and compared to age and sex matched controls (nonsmokers). Basal heart rate was significantly (P < 0.001) higher without any variation in blood pressure in TAO group compared to controls. Valsalva ratio (P < 0.01) and 30:15 ratio (P < 0.001) were increased without any effect on E:I ratio in TAO group versus controls. On head up tilt (HUT), there was significant (P < 0.001) fall in blood pressure in TAO group compared to controls. On cold pressure test (CPT), systolic blood pressure was reduced significantly (P < 0.01) in TAO group than that of controls, however, diastolic blood pressure showed no change in two groups. Responses indicate towards lower sympathetic reactivity in Buerger's patients.