Background/Purpose

Vascular involvement is a key feature of Systemic sclerosis (SSc) and involves both the micro and macrovasculature. Vascular changes are central in the disease’s pathogenesis and the assessment of vascular involvement has a prognostic value, therefore vascular assessment has a pivotal significance, both for research and clinical purpose.

A non invasive technique to monitor cutaneous vascular function is the response to a physiological challenge using laser speckle contrast  imaging. This technique has proven effective and reproducible for the assessment of skin blood flow in SSc patients, either with or without dynamic challenge.

The aim of our study was to evaluate post-occlusive reactive hyperemia test (PORH) in  consecutive SSc patients and to test whether PORH is a useful tool to discriminate different disease subsets within SSc population.

Methods

Patients

Starting from to april 2011 to June 2014, 54 consecutive SSc patients were enrolled (mean age 56 ±15 years, F/M =18). Patients were divided into limited SSc (n=29), Diffuse SSc (n=8) and Very early SSc (VEDOSS) (n=17) according to literature definition.

Laser Speckle Contrast Analysis

Cutaneous blood flow was measured throughout the experiments using a high frame rate LSkI (Pericam PSI system, Perimed, Jarfalla). The occlusive/ischemic test was performed by inflating for 4 minutes a cuff placed on the left arm to 30 mm Hg above the systolic pressure. The recovery time (time needed to recover the basal flux after occlusion in seconds), the peak flux (hyperemic peak reached after occlusion) and the area under the hyperemic curve were recorded.

Statistical analysis

Correlation between clinical data and laser measurements were performed by non parametric tests and contingency tables for cathegorical variables (Stat-View, SAS). In view of the high number of comparisons involved, only p values equal or below 0,01 were considered significant.

Results

A statistical significant difference was detected in the post-ischemic hyperemic peak flow between very early SSc and established SSc (424 vs 137% p = 0,0001). PORH peak flow decreased according to capillaroscopic pattern (early=435%, active=173%, Late=145% P<0,005). Moreover a strong correlation between capillary density and peak flow was unveiled (rho=0,56, p < 0,0001).

Conclusion

These data show a different pattern of vascular involvement in early SSc as compared to established disease that mirror capillaroscopic changes. In this context, functional features of early and established disease seem to be the physiologic counterpart of abnormalities detected by capillaroscopy. POHR test might be a useful aid for further characterization of vascular involvement in SSc.

---

« Back to 2014 ACR/ARHP Annual Meeting

ACR Meeting Abstracts - https://acrabstracts.org/abstract/post-occlusive-reactive-hyperemia-porh-test-mirrors-vascular-changes-in-systemic-sclerosis-ssca-laser-speckle-contrast-lasca-study/