Bosentan fosters microvascular de-remodelling in systemic sclerosis

Area of Science:

• Cardiovascular Medicine
• Rheumatology
• Medical Imaging

Background:

• Systemic sclerosis (SSc) is associated with significant microvascular damage, particularly in patients with pulmonary arterial hypertension (PAH).
• Nailfold videocapillaroscopy (NVC) is a key diagnostic tool for evaluating microvascular abnormalities in SSc.
• Distinct NVC patterns correlate with the severity of SSc-related microvascular damage.

Purpose of the Study:

• To assess the impact of Bosentan, a dual endothelin receptor antagonist, on microvascular modifications in SSc patients with PAH.
• To evaluate changes in NVC patterns after 12 months of Bosentan treatment.

Main Methods:

• Nine SSc patients with NYHA class III-IV PAH received Bosentan (125 mg twice daily).
• NVC was performed before and after 12 months of treatment using optical probe videocapillaroscopy (100x and 200x magnification) with image analysis software.
• A control group of nine PAH SSc patients treated with Iloprost was included.

Main Results:

• Before treatment, seven patients exhibited a 'late' SSc NVC pattern characterized by severe capillary loss and avascular areas.
• After 12 months, seven patients showed a transition from the 'late' to an 'active' SSc NVC pattern.
• Key improvements included the disappearance of avascular areas and capillary hemorrhages; new capillaries suggest angiogenesis.

Conclusions:

• Bosentan therapy demonstrates potential to improve and stabilize microvasculature in SSc patients with PAH, as evidenced by NVC pattern modifications.
• The observed changes, including the emergence of new capillaries, suggest Bosentan may promote angiogenesis and modulate structural vascular changes.
• Bosentan may be a beneficial treatment for managing microvascular complications in SSc-related PAH.