[Aortic stenosis with left ventricular dysfunction: evaluation and management]

Aortic stenosis is the most frequent valvulopathy in France today. Valve replacement has transformed the prognosis, when indications are present before the appearance of irreversible left ventricular dysfunction. However, some patients are still not seen before this time or their surgery was deferred. Thus, the postoperative prognosis depends on the reversibility of this dysfunction which can occur even when the stenosis is severe and essentially reflects the elevated afterload. The prognosis is less favorable once myocardial fibrosis has developed in response to left ventricular hypertrophy or when ischemic cardiopathy contributes to this dysfunction. The diagnosis and prognosis are based on the confirmation of the presence of a severe stenosis and that the removal of this obstacle will lead to regression of the dysfunction. For this, Doppler echocardiography is determinant, as combined with a dobutamine test, it is able to evaluate the tightness of the stenosis, the severity of the left ventricular dysfunction and its reversibility. When the stenosis is severe with contractile reserve, indicating a better postoperative prognosis, dobutamine does not induce an appreciable change of the aortic area, but the mean pressure gradient, often low prior to dobutamine administration, rises. Although the surgical risk remains higher in the presence of left ventricular dysfunction, the ultimate prognosis is more favorable when the test suggests regression is possible.