4 − Severe arrhythmias; cerebrovascular events (e. g. transient ischaemic attack, stroke) within the last 3 months. − Pulmonary hypertension due to venous occlusive disease. − Congenital or acquired valvular defects with clinically relevant myocardial function disorders not related to pulmonary hypertension. − Pregnancy and lactation (see section 4.6).