Low-Flow, Low-Gradient Severe Aortic Stenosis in patients with preserved or reduced ejection fraction: a systematic literature review.

A systematic review of the literature was conducted to analyze the current evidence on low-flow, low-gradient severe aortic stenosis. This analysis aimed to differentiate between subgroups of patients with reduced and preserved left ventricular ejection fraction (LVEF). After conducting a systematic literature review, 35 observational studies were included. Out of these, 28 were prospective and 7 retrospective. The studies that included a mortality risk stratification of low-flow, low-gradient aortic stenosis (LF- LG AS) with both preserved and reduced LVEF were reviewed. The importance of considering multiple clinical and echocardiographic variables in diagnostic evaluation and therapeutic decision-making was highlighted. LF- LG AS, in any of its subgroups, is a common and challenging valve lesion. A careful assessment of severity and, in specific scenarios, a thorough reclassification is important. More high-quality studies are required to more precisely define the classification and prognosis of this entity.