The purposes of this study are (I), to evaluate various screening methods for their ability to predict and to confirm Pulmonary Hypertension (PH) in scleroderma patients, and (II) to evaluate the incidence of PH (i.e. the number of new cases per year) in scleroderma patients.

Inclusion Criteria:

• consent form
• men and women> 18 years
• fulfill the current definition of a collagen vascular disease according to the actual guidelines of the American College of Rheumatology (ACR)

Exclusion Criteria:

• all contraindications for exercise testing
• significant restriction of the left ventricle, unstable coronary artery disease and myocardial infarction in the last 6 months
• patients with other lung diseases (as the pulmonary infestations as part of systemic disease) or related musculoskeletal disorders influencing baseline exercise capacity
• pregnancy

Included are all patients who fulfill the current definition of a collagen vascular disease according to the actual guidelines of the American College of Rheumatology (ACR) and who are 18 years or older.