Imaging Strategies for Evaluating Low-Flow, Low-Gradient Aortic Stenosis with Reduced and Preserved Left Ventricular Ejection Fraction
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Purpose of Review
Aortic stenosis (AS) is one of the most common valvular heart diseases, and aortic valve replacement (AVR) provides both symptomatic and survival benefit in symptomatic severe AS patients. The purpose of this review is to discuss low-flow low-gradient AS which is still a challenging diagnostic entity.
Thirty–forty percent of patients with AS have low flow which makes it difficult to differentiate truly severe AS that benefits from AVR compared to pseudo-severe AS which is currently managed conservatively. Patients with low-flow low-gradient AS (LF-LG AS) include those with reduced left ventricular systolic function (classical LF-LG AS) and those with preserved left ventricular systolic function (paradoxical LF-LG AS). Low-dose dobutamine stress echocardiography (DSE) helps to identify truly severe stenosis in patients with classical LF-LG AS. Aortic valve calcium scoring with multidetector computed tomography plays a major role in patients with paradoxical LF-LG AS and also among classical LF-LG AS patients who have reduced contractile reserve on DSE.
This article will provide an overview of imaging strategies for evaluating LF-LG AS with reduced and preserved left ventricular ejection fraction.
KeywordsAortic stenosis Left ventricular ejection fraction Dobutamine stress Echocardiography Multidetector computed tomography Aortic valve replacement
Compliance with Ethical Standards
Conflict of Interest
Krishna Alluri, Blase A. Carabello, and Rajasekhar Nekkanti declare that they have no conflict of interest.
Human and Animal Rights and Informed Consent
This article does not contain any studies with human or animal subjects performed by any of the authors.
Papers of particular interest, published recently, have been highlighted as: • Of importance •• Of major importance
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