Alteration in diaphragmatic function during cardiac insufficiency: potential pharmacology modulation.

Respiratory muscle dysfunction has been demonstrated in several clinical situations including chronic respiratory disease, such as chronic obstructive pulmonary disease, as well as cardiac insufficiency. In the latter case, respiratory muscle dysfunction has been demonstrated in acute situation (cardiogenic shock) and in chronic cardiac insufficiency. In the former case, it has been shown in an animal model that respiratory muscle dysfunction could influence markedly the outcome of cardiogenic shock. In chronic cardiac insufficiency histologic, biochemical and contractile abnormalities of the respiratory muscles have been demonstrated in an animal model as well as in humans. These alterations may account, at least in part, for the sensation of dyspnea that these patients encountered. Finally, several pharmacological agents such as angiotensin-converting enzyme inhibitors have been shown to restore muscle abnormalities observed during chronic cardiac insufficiency.