The aim of the study is to document the left and right ventricular function in patients with sclerodermia associated pulmonal arterial hypertension via 3D echocardiography. The results of this study should help to generate hypothesis for further future studies.

The primary hypothesis is that the increased use of modern image guided methods could provide essential aspects for the follow up.

The 3D echocardiography could provide early and detailed information about the changes in the left and right ventricle.

The prediction of sclerodermia associated pulmonary arterial hypertension (PAH) is rather adverse, so it makes sense to evaluate relevant changes of the left-ventricular longitudinal strain soon to adapt the PAH specific therapy accordingly.

Inclusion Criteria:

• age >17
• pulmonary arterial hypertension (PAH) associated with WHO group 1 who start a parenteral prostanoid-therapy
• written informed consent
• prostanoid naive
• no change of the PAH specific therapy within 3 weeks of the recruitment to the study

Exclusion Criteria:

• pregnancy and lactation period
• Women of child bearing potential who do not use an effective and secure method for birth control
• severe chronic kidney insufficiency (glomerular filtration rate <30), which will remain for more than 3 months
• liver-insufficiency Child C
• life expectancy shorter than the course of the study (for example because of malignant disease

patients with pulmonary arterial hypertension associated with WHO group 1 who start with a parenteral prostanoidtherapy.