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Updated: Jan 31, 2026

Full-root Aortic Valve Replacement by Stentless Aortic Xenografts in Patients with Small Aortic Roots
Published on: May 21, 2017
The Combined Konno-Nicks Procedure for Severely Stenotic Aortic Root and Left Ventricular Outflow Tract
Masaru Matsuda1, Shin Yajima1, Daisuke Yoshioka1
1Department of Cardiovascular Surgery, University of Osaka, Suita, Japan.
Background:
Patients with a small aortic root and subvalvular stenosis are at risk of prosthesis-patient mismatch, making annular and left ventricular outflow tract (LVOT) enlargement essential.
Case Summary:
We herein report the case of a 41-year-old woman with prosthetic valve dysfunction and severe LVOT obstruction due to pannus formation in whom a 12-mm sizer could not be passed. Redo aortic valve replacement with the combined Konno-Nicks procedure successfully enlarged the annulus and LVOT, enabling the implantation of a 4-size larger prosthesis based on intraoperative sizer measurements. Postoperative echocardiography and computed tomography confirmed effective valve enlargement and preserved valve function.
Discussion:
Combined anterior-posterior enlargement can be valuable for redo aortic valve replacement in patients with a small annulus and subvalvular stenosis to prevent prosthesis-patient mismatch.
Take-Home Message:
The combined Konno-Nicks procedure can effectively relieve prosthetic valve dysfunction with severe subvalvular stenosis by enabling larger prosthesis implantation.
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