The heart and pulmonary arterial hypertension in systemic sclerosis

Systemic sclerosis (SSc) is an autoimmune connective tissue disease characterized by vasculopathy and progressive fibrosis of the skin and visceral organs (gastrointestinal tract, heart, kidneys and lungs). Although the prevalence is low, SSc is a disease with high morbidity and mortality. Since pulmonary arterial hypertension (PAH) associated with SSc (SSc-PAH) and clinically evident cardiac involvement is associated with increased mortality, the cardiac complications and PAH in SSc are reviewed. Both diffuse cutaneous (DcSSc) and limited cutaneous (LcSSc) subgroups are at risk for cardiac involvement and SSc-PAH. Cardiac involvement can be divided in pericardial involvement, myocardial involvement and rhythm disturbances and mostly occurs asymptomatically. However, when symptomatic, it is associated with a poor prognosis. Screening for asymptomatic cardiac involvement should be considered in SSc in order to initiate treatment in an early stage. However, there are no randomized controlled trials on treatment options for cardiac involvement in SSc. SSc-PAH is a devastating complication of SSc, which can develop early in DcSSc and LcSSc. Screening for PAH should be performed since screening leads to earlier diagnosis and earlier treatment is associated with a better prognosis. Today, screening is performed by clinical judgement and echocardiography. Recently the DETECT algorithm, a 2-step screening algorithm is proposed in a SSc-subgroup at increased risk for PAH, but further validation is needed. Despite current treatment options with prostacyclins, endothelin-1 receptor antagonists and phosphodiesterase type-5 inhibitors, mortality remains high. Several promising new treatment options for PAH are evaluated in phase II and III clinical trials.