Dysfunctional arteriovenous anastomoses in hands of systemic sclerosis patients with digital ulcers.
OBJECTIVE
Previous studies indicate that the arteriovenous anastomoses (AVAs) and the arterioles with the nutritive flow are involved in the pathophysiologic process disturbing hand blood flow in systemic sclerosis (SSc). However, impact of different part of the microvascular system involved in digital ulcers (DU) is not well known. Here, we aimed to assess the vasomotor activity of the AVAs in the hands of patients with and without DU in SSc.


METHODS
Simultaneous recordings were made of laser Doppler flux in the finger pulp and thenar eminence, together with ipsilateral radial artery blood velocity and mean arterial blood pressure (MAP) in 22 non-smoking SSc patients and 13 aged-matched healthy controls.


RESULTS
AVA responses in the finger pulp to spontaneous vasoconstrictor nerve impulses were abolished in 64% of the SSc patients. Correlation and cross-spectra analysis showed positive correlation between blood flow changes and MAP changes, indicating a passive vascular bed in the SSc finger pulp with blood flow variations depending on short-term variability in MAP. Dysfunctional AVAs were identified in all the patients with a history of DU (n=8), while none of the patients with normal AVA function had episodes of DU (n=8) (p= 0.017).


CONCLUSIONS
We found that in SSc patients with DU there is a dysfunction of the AVAs of the finger pulp. This proof-of-concept study supports the notion that AVA dysfunction may play a critical role in SSc related DU. AVA dysfunction may be a part of autonomic dysfunction in SSc.
Department of Dermatology, Oslo University Hospital, Oslo, Norway. kbergers@ous-hf.no.
T K
TK
Bergersen
A-M
AM
Hoffmann-Vold
Ø
Ø
Midtvedt
J T
JT
Gran
C
C
Mørk
K
K
Toska
M
M
Elstad
D000368:Aged; D001163:Arteriovenous Anastomosis / Q000503:physiopathology*; D016022:Case-Control Studies; D005260:Female; D005385:Fingers / Q000098:blood supply*; D006229:Hand Dermatoses / Q000209:etiology / Q000503:physiopathology*; D006801:Humans; D017078:Laser-Doppler Flowmetry; D008297:Male; D008833:Microcirculation; D008875:Middle Aged; D011928:Raynaud Disease / Q000209:etiology / Q000503:physiopathology*; D012039:Regional Blood Flow; D012595:Scleroderma, Systemic / Q000150:complications / Q000503:physiopathology*; D012883:Skin Ulcer / Q000209:etiology / Q000503:physiopathology*