Pulmonary arterial hypertension is a disease characterised by pathological changes in the pulmonary arteries leading to a progressive increase in pulmonary vascular resistance and pulmonary artery pressure. Right ventricular failure is the main cause of death in patients with pulmonary arterial hypertension, and the ability of the right ventricle to adapt to the progressive increase in pulmonary vascular resistance associated with changes to the pulmonary vasculature in pulmonary arterial hypertension is the main determinant of a patient's functional capacity and survival.

Right ventricular dyssynchrony was present in a substantial proportion of patients with pulmonary arterial hypertension and this dyssynchrony adversely affected right ventricular function.

Inclusion Criteria:

• Pulmonary hypertension type I, III, IV, V Dana Point classification
• NYHA classification equal or superior to stage II
• During right catetherization : cardiac index inferior or equal 2.5 L/mn/m2 and atrial pressure superior or equal 10 mmHg OR cardiac index equal or inferior to 2.2 L/mn/m2
• Optimal therapy considered by the referring specialist practioner of the patient

Exclusion Criteria:

• Minor or incapacitated adult
• Pregnancy
• Unability to give free and informed consent
• Pulmonary hypertension type II Dana Point classification
• Eisenmenger syndrome
• Patent foramen ovale
• Left bundle-brach block
• Pulmonary hypertension exacerbation
• Medical clinical situation considered inappropriate by the investigator
• Patient eligible for a heart-lung transplant
• Patient eligible for pulmonary endarterectomy
• Patient with poor echogenicity
• Filter in the inferior vena cava