Original articleFlow dependence of the aortic valve area in patients with aortic stenosis: Assessment by application of the continuity equation☆
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Cited by (24)
Transvalvular Flow Rate Determines Prognostic Value of Aortic Valve Area in Aortic Stenosis
2020, Journal of the American College of CardiologyCitation Excerpt :Our observations are mechanistically supported by studies showing change in AVA with change in Q. In an in vitro model, Voelker et al. (9) showed that changing Q from 100 to 200 ml/s changed measured AVA by 24%, whereas there was minimal change in AVA by changing Q from 200 to 300 ml/s. Rask et al. (10) showed that Q significantly altered AVA measurement by continuity equation. They showed that the percentage change in AVA was roughly one-half (0.56) the percentage change in Q, such that a 50% change in Q (e.g., from 160 to 240 ml/s) could alter AVA by 25%.
Flow Rate in Aortic Stenosis: Clinical Tool, Hemodynamic Insight, or Both?
2020, Journal of the American Society of EchocardiographyAssessment of Severity in Aortic Stenosis-Incremental Value of Endocardial Function Parameters Compared With Standard Indexes
2007, Ultrasound in Medicine and BiologyCitation Excerpt :Peak and mean transvalvular gradients were calculated by using the modified Bernoulli equation. Aortic valve area was determined by transthoracic echocardiography using the standard continuity equation (Oh et al. 1988; Rask et al. 1996; Donal 2005) and by transesophageal echocardiography using area planimetry (Hoffmann et al. 1993). The general principles that underlie the TDI modalities have been previously described (McDicken et al. 1992).
Flow-dependent changes in doppler-derived aortic valve effective orifice area are real and not due to artifact
2006, Journal of the American College of CardiologyCitation Excerpt :The EOA is the standard parameter for the assessment of the severity of aortic valve stenosis, and it was initially believed to be a flow-independent parameter. However, many studies have subsequently reported that EOA determined by Doppler or by catheterization may vary with increasing flow rate in patients with aortic stenosis (22–35). Several in vitro studies have also reported that EOA may increase with flow rate in both rigid and flexible (i.e., bioprosthetic valves) orifices (7,21,29,36,37).
Dobutamine hemodynamics for aortic stenosis with left ventricular dysfunction
2005, Annales de Cardiologie et d'AngeiologieEstimation of aortic valve effective orifice area by Doppler echocardiography: Effects of valve inflow shape and flow rate
2004, Journal of the American Society of Echocardiography
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Supported in part by the Umeå University Research Foundation.