Severe low-gradient aortic stenosis: impact of inadequate left ventricular responses to high afterload on diagnosis and therapeutic decision-making

AbstractThe fact that nearly 50% of patients with an aortic valve (AV) area  <  1.0 cm2, consistent with severe aortic stenosis (AS), can have mean trans-AV pressure gradients  <  40 mmHg, consistent with non-severe AS, indicates that “low-gradient” (LG) severe AS, which is often associated with poor prognosis, deserves particular consideration. Inadequate left ventricular (LV) adaptation to severe AV stenosis resulting from preexistent intrinsic myocardial damages an d/or maladaptive LV responses to increased afterload are typical features of severe LG-AS. The diagnosis and management of patients with severe LG-AS are particularly challenging because the discrepancy between the AV area and the trans-AV pressure gradient raises doubts concerning the actual severi ty of AS and therefore also about the necessity of AV replacement (AVR). LG-AS diagnosis requires integrative multimodality evaluation of both the AV and the LV and therapeutic decision-making necessitates careful individual benefit-risk estimation. Although patients with severe LG-AS associated wit h low trans-AV flow (i.e., stroke volume ≤ 35 ml/m2) have worse outcomes after AVR than those with high-gradient severe AS, even those with reduced LV ejection fraction (LVEF) can have a significant survival benefit particularly by transcatheter AVR. Dobutamine stress echocardiography facilitates distinction between true-severe and pseudo-severe low-flow LG-AS with reduced LVEF. The review aimed ...
Source: Heart Failure Reviews - Category: Cardiology Source Type: research