Measurement of the cutaneous blood flow reserve in normal humans by laser-Doppler flowmetry.

AIM: To assess the normality of the cutaneous blood flow reserve (CR). METHODS: To explore the feasibility and reproducibility of laser-Doppler flowmetry for CR measurement, we prospectively measured CR in 17 healthy subjects on the dorsum of the foot and pulp of the big toe. CR was defined as the sum of the venoarteriolar reflex (VAR), i.e. postural vasoconstriction, and postischemic reactive vasodilation (H), expressed as % of the resting supine flux and assessed by using laser-Doppler flowmetry. RESULTS: For the dorsal foot, VAR%+/-SEM was 61+/-14, H%, 752.5+/-214 and CR, 813.5+/-217. On the pulp of the big toe, VAR% was 61.6+/-4.7, H%, 588.2+/-174 and CR, 649.9+/-176. CR measurement variability was assessed by calculating the inter-individual coefficient of variation of CR, which was 1.1 for both the dorsal foot and pulp of the big toe. Reproducibility was assessed by calculating the CR intraclass correlation coefficient, which was 0.49 for the dorsal foot and 0.64 for the pulp of the big toe. CONCLUSIONS: The CR is proposed as a new parameter for assessing the microvascular integrity and contractile reserve of the skin. Laser-Doppler flowmetry is suitable for this non-invasive evaluation. The method displayed large variability, and its reproducibility varied from moderate for the dorsal foot, to substantial for the toe. Further studies are necessary to demonstrate its clinical usefulness.

Cutaneous microvascular effects of mid-term hormone replacement therapy in healthy postmenopausal women: a prospective placebo controlled trial.

OBJECTIVE: To study the mid-term effects of Hormone Replacement Therapy (HRT) on cutaneous microcirculatory blood flow and reactivity in healthy postmenopausal women. DESIGN: In a double-blind placebo controlled randomized study, 16 healthy postmenopausal women received either placebo or HRT (micronized estradiol: 1 mg/day, day 1-28, promegestrone: 0.25 mg/day, day 14-28). This regimen was completed 6 times. Cutaneous microcirculatory blood flow was recorded by laser-Doppler velocimetry on the foot dorsum, in the supine and then dependent positions, and after post-ischemic hyperemia. RESULTS: At day 0, the two groups were similar and none of the following data differed significantly between treated and placebo group: (supine flux: 11.8 +/- 1.8 u vs. 13.2 +/- 3.9, venoarteriolar reflex: 5.6 +/- 1.3 vs. 6 +/- 3.3, and post-ischemic hyperemia: 35.2 +/- 3.9 vs.48.3+/-11). At the end of the study (day 26-28 of 6th cycle), the supine flux was 9.8 +/- 2.1 in the HRT group vs.12.9 +/- 6 in the placebo group (NS), the venoarteriolar reflex, 1.2 +/- 2 vs. 7+/-1.7 (p=0.04), and post ischemic hyperemia, 31.8 +/- 5.4 vs. 39.5 +/- 4.6 (NS). Intragroup values did not change significantly for any of the microcirculatory parameters measured, which remained stable throughout the 6 months of the study. Intergroup values for these parameters did not change either, except for the venoarteriolar reflex, which was lower at the end of the study in the HRT (EP period, cycle 6 day 26-28) than placebo group (p=0.04). CONCLUSIONS: HRT does not impair the resting supine cutaneous microcirculation blood flow or post-ischemic hyperemia.

[Treatments of progressive systemic sclerosis]. / Evolution des traitements de fond de la sclérodermie.

Progressive Systemic Sclerosis (PSS) is still an incurable disease but there are treatments for it, and the list of proposed treatments is long. The methodology of trials concerning PSS is complex, due to the low prevalence of the disease and therefore its financial interest for pharmaceutical companies, the lack of simple end points for efficacy, and the large number of clinical expressions with various prognoses. These causes explain why most open studies are fiercely positive, and why controlled studies are so rare. The progress made during the last 10 years concern 1) the diagnosis, which is now made earlier due to capillaroscopy and antibody assays, especially of anticentromere antibodies, 2) better knowledge of the prognosis, due to the classification of PSS into limited and the diffuse forms which have different prognoses, and 3) the recognition of a serious complication of the disease, ie. pulmonary hypertension, which can now be detected by non-invasive methods. All these improvements will also improve the methodology of future trials of drugs for treating PSS. In this ocean of uncertainties, some treatments have a valid background, and 3 visceral locations of PSS can be efficiently treated: renal involvement, with angiotensin-converting enzyme inhibitors, respiratory involvement, with D-penicillamine, and pulmonary hypertension, with prostacyclin derivatives. Corticosteroids are suspected to increase the risk of renal complications. Calcium blockers are considered a useful symptomatic treatment of the associated Raynaud's phenomenon and of the risk of digital necrosis, and may also constitute a treatment of PSS itself. A recent trial conducted by the French Microcirculation Society and its acrosyndrome Study Group considered the effects of an oral derivative of prostacyclin. Beneficial effects were: a reduction of the risk of digital necroses, improved overall wellbeing, less necessity for hospitalizations, fewer giant capillaries, and a dramatic fall in the level of von-Willebrand factor.

[Cannabis and tobacco: cofactors favoring juvenile obliterative arteriopathy]. / Cannabis et tabac. Co-facteurs favorisant l'artériopathie oblitérante juvénile.

The causal effect of cannabis, associated or not with smoking, in juvenile thromboangiitis disorders such as Leo Buerger disease, has been suggested. We describe here a case of a 30-year-old woman who smoked cannabis and developed intermittent claudication of the lower limbs. Female sex and proximal localization of the lesions (external iliac artery) are not usually described in "cannabis arteritis". Cannabis would be involved not only in the pathogenesis of juvenile obstructive arteriopathy, but also in the development of atheromatous lesions in the young subject.

Clinical significance of subcutaneous calcinosis in patients with systemic sclerosis. Does diltiazem induce its regression?

OBJECTIVE: To establish whether diltiazem reduces subcutaneous calcinosis (SCC) in patients with systemic sclerosis (SSc), and whether this calcinosis is related to other signs or symptoms. METHODS: 47 patients with SSc were evaluated and divided into two groups according to the presence or absence of SCC. RESULTS: Among the 12 patients with SCC who were treated with diltiazem and had sequential hand radiographs (differential time between the two radiographs: 7.8+/-4 years), there was a slight radiological improvement in three patients only. More patients with SCC had anticentromere antibodies than patients without (p = 0.003), fewer had anti-Scl 70 antibodies (p = 0.01), more had telangiectasia and giant capillaries ( p + 0.04 and 0.048 respectively), and SCC patients had significantly fewer capillaries at the nailfold (p = 0.03). CONCLUSION: These results do not clearly indicate that diltiazem is effective in calcinosis associated with SSc. Among the patients with SSc, those who also had SCC exhibited a distinctive autoimmune profile and more severe cutaneous capillary injury than those without SCC.