POS0890 MACROVASCULAR DYSFUNCTION AND ITS CLINICAL IMPLICATION IN SYSTEMIC SCLEROSIS
Authors: D. Bairwa, C. Kavadichanda, V. Negi
Journal: Annals of the Rheumatic Diseases (2021)

Background: Even though microvascular dysfunction has been implicated in pathogenesis of scleroderma (SSc), there is minimal evidence to suggest presence of macrovascular dysfunction. The clinical implication of macrovascular dysfunction in SSc is unknown. Moreover, data on the correlation between dysfunction in small and large blood vessel is inconclusive. [1-2] Objectives: To study the correlation between macrovascular dysfunction as assessed by percent change in flow mediated vasodilation (FMD) of brachial artery and microvascular dysfunction as assessed by nail fold capillaroscopy (NFC) findings in SSc. To assess the clinical impact of macrovascular dysfunction. Methods: This cross-sectional comparative study enrolled patients with SSc and age and gender matched healthy controls. FMD change was calculated using standard USG probe of 5 to 6 MHz in right brachial diameter from the average of 3 consecutive end diastolic frames. NFC was performed using portable nail fold capillary microscope at 800X magnification. Clinical features of SSc were compared between SSc patients with and without macrovascular dysfunction. Results: This study enrolled 59 SSc patients including 29 (49.2%) diffuse, 20 (20.4%) limited, 08 (10.2%) sine SSc and 2 patients (3.4%) with myositis overlap. SSc patients had significantly (p-&lt;0.0001) lower % FMD change compared to healthy controls. NFC showed significantly higher architecture distortion (p-&lt;0.0001), loss of capillaries (p-&lt;0.0001) and abnormal capillaries (p-&lt;0.0001). There was no correlation between FMD change and capillary density (p-0.381), avascular area (p-0.266) and abnormal capillaries (p-0.899). None of the clinical features like pulmonary hypertension, digital ulcer burden, acro-osteolysis and auto amputation were different between SSc with and without macrovascular dysfunction. Conclusion: Macrovascular dysfunction in SSc is substantial and it seems to be independent of the microvascular dysfunction. The clinical implications of macrovascular dysfunction are yet to be identified. References: [1]Schioppo T, Orenti A, Boracchi P, De Lucia O, Murgo A, Ingegnoli F. Evidence of macro- and micro-angiopathy in scleroderma: An integrated approach combining 22-MHz power Doppler ultrasonography and video-capillaroscopy. Microvasc Res. 2019 Mar;122:125–30. [2]Rollando D, Bezante GP, Sulli A, Balbi M, Panico N, Pizzorni C, et al. Brachial Artery Endothelial-dependent Flow-mediated Dilation Identifies Early-stage Endothelial Dysfunction in Systemic Sclerosis and Correlates with Nailfold Microvascular Impairment. J Rheumatol. 2010 Jun 1;37(6):1168–73. Table 1. Comparison of various parameters between the SSc patients with healthy controls. Parameter Frequency (percentage)/median (interquartile range ) SSc patients (n=59 ) Healthy controls (n=64 ) Demographic details Age in years 38 (27-46) 36.5 (28.25-42) Gender Male 03 (5.1%) 03 (4.7%) Female 56 (95.1%) 61 (95.3%) FMD findings FMD % change* 4.54 (3.13-8.82) 10.30 (8.33-13.16) NFC findings Number of capillaries* 51 (38-63) 121 (113-128) Average capillary density* 3.19 (2.38-3.94) 7.56 (7.06-8) Disorganized architecture (%)* 37.5 (12.5-37.5) 0 U shape (%)* 50 (36.59-68.09) 85.51 (82.97 – 88.53) Abnormal (%)* 36.11 (14.03-55.26) 0 Enlarged (%)* 10.63 (2.94-23.68) 0 Giant (%)* 21.05 (0-45.45) 0 Microhemorrhages (%)* 6.25 (0-12.5) 0 Neoangiogenesis (%)* 3.85 (0-20) 0 Avascular area (%)* 50 (31.25- 75) 0 *parameters with statistically significant (p value&lt; 0.0001) difference among two groups. SSc; Systemic Sclerosis, FMD; flow mediated vasodilatation, NFC; nail fold capillaroscopy Figure 1. Scatter plot showing correlation between FMD percentage change and average capillary density. (r= 0.116) (P-value - 0.381) Disclosure of Interests: None declared