Left ventricular failure leads to circulatory failure which causes clinical symptoms and in which regional blood flow changes play an important role. An abnormality of systemic vasodilatation on exercise or on pharmacological intervention has been shown. This affects both the resistance and conductive vessels and is mainly functional, related to neurohormonal stimulation with a predominance of vasoconstrictive factors amongst which increased adrenergic tone probably plays an essential part. A modification of the endothelium-dependent response has recently been confirmed. The presence of structural vascular abnormalities (increase in parietal sodium and water concentrations, "remodelling" remains debatable in the human. These abnormalities have a common factor in their chronicity and take time to regress with medical treatment or after cardiac transplantation. Physical training seems to induce more marked and, above all, more rapid effects.