Validation of Conventional and Simplified Methods to Calculate Projected Valve Area at Normal Flow Rate in Patients With Low Flow, Low Gradient Aortic Stenosis: The Multicenter TOPAS (True or Pseudo Severe Aortic Stenosis) Study
Section snippets
Methods
The protocol of the True or Pseudo Severe Aortic Stenosis (TOPAS) multicenter prospective observational study was described in detail in our previous publications.4, 5, 9 Briefly, between July 2002 and March 2008, we recruited 142 patients with low-flow, low-gradient AS, defined as AVA ≤ 1.2 cm2, indexed AVA ≤ 0.6 cm2/m2, a mean transvalvular gradient ≤ 40 mmHg, and an LV ejection fraction ≤ 40%. All patients underwent DSE using commercially available ultrasound systems, and functional capacity
Results
The mean age of the cohort was 73 ± 10 years, 108 (76%) were men. Systemic arterial hypertension was present in 60% of the patients, diabetes in 37%, coronary artery disease in 70%, multivessel coronary disease in 51%, and previous myocardial infarctions in 58%. Although 73 (51%) had no or minimal myocardial contractile reserve as defined by a percentage increase in stroke volume < 20%,3 the vast majority of the patients (92%) included in this series had significant increases in mean Q during
Discussion
We have previously reported that AVAproj can mitigate important interindividual variability in Q response during DSE and result in improved diagnostic accuracy compared with traditional dobutamine stress echocardiographic criteria for distinguishing TS from PS AS in patients with low-flow, low-gradient AS.9 However, the main limitations of the previous study were its limited sample size (n = 23), the absence of quantitative reference method to corroborate stenosis severity, and the absence of
Conclusions
Appropriate distinction between TS and PS AS is essential for therapeutic decision making in patients with LV dysfunction and low-flow, low-gradient AS. The results of this study demonstrate that AVAproj better predicts underlying AS severity and patient outcomes than traditional dobutamine stress echocardiographic indices in these patients. Importantly, simplified AVAproj is easier to calculate than conventional AVAproj, thus facilitating the use of AVAproj in clinical practice.
Acknowledgments
We thank Jocelyn Beauchemin and Isabelle Fortin for data collection and technical assistance.
References (18)
- et al.
Usefulness of dobutamine echocardiography in distinguishing severe from nonsevere valvular aortic stenosis in patients with depressed left ventricular function and low transvalvular gradients
Am J Cardiol
(1995) - et al.
Comparison of valve resistance with effective orifice area regarding flow dependence
Am J Cardiol
(2001) - et al.
Hemodynamic stability of valve area, valve resistance and stroke work loss in aortic stenosis: a comparative analysis
J Am Soc Echocardiogr
(2002) - et al.
Aortic valve replacement for low-flow/low-gradient aortic stenosis: operative risk stratification and long-term outcome: a European multicenter study
J Am Coll Cardiol
(2008) - et al.
Comparison of the hemodynamic performance of percutaneous and surgical bioprostheses for the treatment of severe aortic stenosis
J Am Coll Cardiol
(2009) - et al.
Size-adjusted left ventricular outflow tract diameter reference values: a safeguard for the evaluation of the severity of aortic stenosis
J Am Soc Echocardiogr
(2009) - et al.
Low-gradient aortic stenosis: operative risk stratification and predictors for long-term outcome: a multicenter study using dobutamine stress hemodynamics
Circulation
(2003) Low-flow, low-gradient aortic stenosis: from evaluation to treatment
Curr Opin Cardiol
(2007)- et al.
Low-gradient aortic valve stenosis. Value and limitations of dobutamine stress testing
Heart
(2007)
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This work was supported by grant 57445 from the Canadian Institutes of Health Research (Ottawa, ON, Canada). Dr Pibarot holds the Canada Research Chair in Valvular Heart Diseases at the Canadian Institutes of Health Research. Dr Mathieu is a research scholar at Fonds de Recherches en Santé du Québec (Montreal, QC, Canada).