Abstract 10411: Outcome of Patients Presenting with Small Aortic Valve Area and Low Gradient Despite Preserved LV Ejection Fraction
Background: In patients with preserved LV ejection fraction (LVEF), a discordance between the aortic valve area (AVA<1cm2) and the mean gradient (MG<40mmHg)raises uncertainty regarding the actual severity of the aortic stenosis (AS) and the therapeutic management. Some investigators suggested that this discordance is due to inconsistency in the guidelines criteria, whereas others reported that this entity may be related to the presence of a severe stenosis with concomitant “paradoxical” low flow. Thus, we compared the outcome of patients with concordant findings to that of patients with discordant findings.
Methods and Results: In a cohort of AS patients with preserved LVEF (>50%), we identified 167 patients with discordant findings: i.e. a priori severe AS on the basis of an AVA<1cm2 and an indexed AVA<0.6cm2/m2 but with a MG<40mmHg (SAS-LG group). These patients were matched, (a) according to the gradient with 167 patients with a moderate AS (AVA>1cm2 and an indexed AVA>0.6cm2/m2) (MAS-LG group) and (b) according to the AVA with 167 patients with a severe AS (AVA<1cm2 and indexed AVA<0.6cm2/m2) with a MG>40mmHg (SAS-HG group). Compared to patients in SAS-HG and MAS-LG groups, patients with in SAS-LG group were older (75±12 vs.66±15 and 68±13 years, respectively; p<0.0001), had higher prevalence of coronary artery disease (66 vs. 47 and 49%; p=0.0001), lower indexed stroke volume (30±4 vs. 48±8 and 46±8ml.m-2; p<0.0001) and lower LVEF (62±8 vs. 68±7 and 65±7%; p<0.0001). During a mean follow-up of 4.2±2.4 years, there were 114 deaths. Patients with SAS-LG had lower 5-year survival compared to patients with SAS-HG or MAS-LG (63±4 vs. 84±3 and 81±3%, respectively; p<0.0001). After adjustment for age, gender, coronary artery disease, previous myocardial infarction, diabetes, type of treatment, MG, and LVEF, patients with SAS-LG displayed increased mortality risk (Hazard ratio>1.6; p=0.03).
Conclusion: These findings provide further evidence that a substantial proportion of patients with severe AS may paradoxically have low transvalvular flow and low gradient despite the presence of normal LVEF. In case of discordance between AVA and gradient, other echocardiographic or diagnostic tests should be considered to corroborate the stenosis severity.
- © 2010 by American Heart Association, Inc.