Cerebral Vasomotor Reactivity in Medically Stabilized Patients with Takayasu's Arteritis

Objective: Takayasu arteritis (TA) is a large vessel vasculitis that affects the aorta and its main branches in the young population. Although data about the effects of controlling disease activity with immunosuppressive treatments on cerebral circulatory capacity are limited, these treatments might stabilize the cerebrovascular hemodynamic status, regardless of the severity of proximal arteriopathy. One of the causes might be the normalization of cerebral autoregulation by the treatment. Materials and Methods: Cerebral vasomotor reactivity (cVMR) was calculated using the breath holding index (BHI) after bilateral middle cerebral artery (MCA) flow pattern was detected using transcranial Doppler ultrasound (TCD) in six patients with TA who were stabilized with treatment (age: 29 +/- 7 years, 5 female). A total of 28 measurements were performed. The control group included 18 healthy volunteers, except for migraine (29 +/- 6 years, 12 female). Bilateral MCA mean flow rates (Vmean, cm/s), pulsatility indexes (PI) and BHI were compared using non-parametric statistical methods. Results: Middle cerebral artery Vmean and PI values were lower in patients with TA (48.3 +/- 17.2 cm/s and 0.31 +/- 0.16, respectively) compared with the controls (62.2 +/- 11.3 and 0.70 +/- 0.11, respectively) (both p<0.001). BHI was measured as 0.92 +/- 0.63 in the TA group and 0.93 +/- 0.38 in the controls (p=0.97). Additionally, in the TA group, TCD parameters measured in the occluded carotid artery territory (11 tests) did not differ from those measured in the non-occluded parent carotid artery territory. Conclusion: It seems that cVMR can be stabilized at least in the medium range in patients with TA. A protected or improved cerebral microcirculation in patients with TA, unlike in patients with atherosclerotic cervicocephalic artery occlusions, might be an explanation.