Fewer Than Half patients with Severe Aortic Stenosis Get New Valves

Although valve replacement was traditionally performed via open-heart surgery (surgical AVR [SAVR]), the development of transcatheter AVR (TAVR) expanded options for AVR to the majority of patients with AS. Yet, despite the widespread availability of effective treatment options, barriers to treatment persist. Also, limited data suggest symptomatic severe AS remains undertreated. Therefore, Dr Shawn X. Li and his team conducted a study to investigate temporal trends in AVR utilization among patients with a clinical indication for AVR.

In this study, the researchers included 10, 795 patients with severe AS (aortic valve area <1 cm2) on transthoracic echocardiograms. They further classified them based on clinical guideline indications for AVR and divided them into the following 4 AS subgroups:

• High Gradient With Normal Left Ventricular Ejection Fraction (Lvef) (HG-NRF),
• High Gradient With Low Lvef (HG-LEF),
• Low Gradient With Normal Lvef (LG-NEF), And
• Low Gradient With Low LVEF (LG-LEF).

The researchers then examined the utilization of AVR and identified predictors.

Key findings of the study:

• Among 10,795 patients, the researchers noted that 6,150 (57%) had an indication or potential indication for AVR, of whom 2,977 (48%) received AVR.
• They also noted that the frequency of AVR varied by AS subtype with LG groups less likely to receive an AVR (HG-NEF: 70%, HG-LEF: 53%, LG-NEF: 32%, LG-LEF: 38%).
• Although AVR volumes grew over the 18-year study period, they mentioned that these were paralleled by comparable growth in the number of patients with AVR indication.
• In patients with a Class I indication, they found that younger age, coronary artery disease, smoking history, higher hematocrit, outpatient index transthoracic echocardiogram, and LVEF ≥0.5 were independently associated with an increased likelihood of receiving an AVR.
• They further highlighted that the AVR was associated with improved survival in each AS-subgroup.

The authors concluded, "Over an 18-year period, the proportion of patients with an indication for AVR who did not receive AVR has remained substantial despite the rapid growth of AVR volumes."

In an accompanying editorial, Dr Brian R. Lindman and Dr Angela Lowenstern wrote, "Li et al report an equally disturbing scenario with respect to the undertreatment of aortic stenosis (AS) with aortic valve replacement (AVR): <50% of those with an indication or potential indication for AVR underwent the procedure."

They further added, "The report by Li et al is thorough and compelling, supported by data indicating that most apparently untreated patients were not simply treated in another health care system…Data such as these ought to galvanize action to not simply carry on, in the same way, hoping for a different result, but to date, they have not. What can be done? Although education and awareness campaigns are needed, such efforts alone have and will continue to fall short of substantively moving the needle. There is an urgent need for a new approach."

For further information:

DOI: https://www.jacc.org/doi/10.1016/j.jacc.2021.11.060

Keywords: aortic stenosis, aortic valve replacement, high gradient with normal left ventricular ejection fraction, high gradient with low LVEF, low gradient with normal LVEF, low gradient with low LVEF, trans-catheter aortic valve implantation, Surgical aortic valve replacement, Undertreatment, Journal of American College of Cardiology, TAVR.