Rôle de l'hémodynamique Doppler de stress dans la prise en charge des rétrécissements aortiques avec dysfonction ventriculaire gauche

Patients with aortic stenosis (AS) and left ventricular (LV) systolic dysfunction have a poor short-term prognosis. In this setting, the decrease in transaortic gradients has an independent prognostic value for operative risk and long-term outcome. The 2 main issues for these patients are: 1/ The real severity of AS; 2/ How to stratify operative risk and evaluate long-term prognosis. Dobutamine Hemodynamics has the potential to address these issues. In case of relative AS, valve area is increased by dobutamine (final valve area >1.2 cm2 with a mean pressure gradient < 30 mmHg); on the basis of published data, medical treatment is justified in this case. Left ventricular contractile reserve is defined an increase in stroke volume, by 20 % or more, under dobutamine. Operative risk is between 5 and 11 % in case of LV contractile reserve and long-term outcome is improved by surgery in this case. In contrast, operative risk varies from 30 to 60 % in case of exhausted reserve; this risk is also determined by other factors such as the presence of coronary artery disease and associated comorbidities. All these parameters are factored into risk-benefit analysis in order to determine the best therapeutic approach for each patient.