A contemporary review of transcatheter aortic valve replacement in low-gradient aortic stenosis

Abstract

Transcatheter aortic valve replacement (TAVR) has been approved for patients with severe symptomatic aortic stenosis (AS) across the spectrum of surgical risk. Although there is substantial evidence regarding the utility of TAVR in patients with classic high-gradient symptomatic AS, the management of patients with discordant AS and gradients that are lower than expected remains uncertain. As low-gradient AS is quite prevalent, it warrants our attention. The TAVR approach in these patients requires risk stratification and additional imaging modalities, such as stress echocardiography, to more accurately evaluate the severity of AS. TAVR complications include stroke, kidney injury, conduction abnormalities, devicerelated thrombosis, endocarditis, and mechanical or vascular complications, which affect both patients with low- and high-gradient AS (HGAS). Contemporary research has demonstrated that TAVR is more effective in the low-gradient AS population than in the HGAS population and shows better outcomes than conservative management. The management of patients with AS, particularly low-gradient AS, remains poorly understood.

Keywords

Transcatheter aortic valve replacement / Aortic stenosis / Low-flow lowgradient aortic stenosis / Valvular heart disease

Acknowledgments

None.

Funding

None.

Conflict of interest

The authors declare they have no competing interests.

Author contributions

Conceptualization: Tom Kai Ming Wang

Writing - original draft: Muhammad Majid, Akiva Rosenzveig, Elio Haroun, Aro Daniela Arockiam, Ankit Agrawal, Sharmeen Sorathia, Rochell Issa, Tiffany Dong, Nithila Sivakumar

Writing - review & editing: Muhammad Majid, Akiva Rosenzveig, Tom Kai Ming Wang

Ethics approval and consent to participate

Not applicable.

Consent for publication

Not applicable.

Availability of data

Not applicable.

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