June 4, 2026Open Access

Clinical Course and Mid- to Long-Term Outcome of Chimney Stenting in Patients With Small Anatomy Undergoing Self-Expanding Transcatheter Aortic Valve Implantation

Q: What is the clinical evidence from this study?

Study design: Observational. Population: Severe aortic stenosis (n=315). Intervention: Prophylactic chimney stenting vs. Standard TAVI without chimney stenting. Primary outcome: All-cause mortality over a mean follow-up of 4.3 years (p=0.756).

Key Result

Prophylactic chimney stenting during transcatheter aortic valve implantation in patients at high risk for coronary obstruction resulted in mid- to long-term mortality comparable to standard TAVI.

Key Points

This study aims to assess the mid- to long-term outcomes of prophylactic chimney stenting during transcatheter aortic valve implantation in high-risk patients.
14 high-risk patients selected for chimney stenting out of 315 total TAVI procedures between 2015 and 2022.
Clinical outcomes compared with a non-CS group (n=301) using preprocedural computed tomography for anatomy assessment.
Follow-up duration averaged 4.3 years; dual antiplatelet therapy was administered for about 7.4 months to 93% of CS patients.
4.3-year follow-up showed mortality rates in the CS group were similar to the non-CS group (log-rank P=0.756).
CS group patients had significantly smaller aortic root dimensions and lower left coronary heights compared to non-CS group patients (9.6 vs. 12.5 mm; P<0.001).
Chimney stenting is suggested as a viable option for high-risk patients to prevent coronary obstruction during TAVI.

Study Design

Type

Observational (n=315)

Multicenter

PICO

Population

315 patients with symptomatic severe aortic stenosis undergoing transcatheter aortic valve implantation with self-expanding valves, followed for a mean of 4.3 years.

Intervention / Comparator

Prophylactic chimney stenting vs Standard TAVI without chimney stenting

Primary Outcome

All-cause mortality over a mean follow-up of 4.3 years, p=0.756

Main Result

p-value: p=0.756

Limitations

Single-center, retrospective observational study design
Small sample size of the chimney stenting group (n=14)
Chimney stenting patients were predominantly small-statured women, limiting generalizability to larger or male patients
Lack of standardized criteria for chimney stenting indication and uniform procedural technique
Very long-term outcomes beyond 10 years remain unknown

Abstract

Background: Coronary obstruction (CO) is a catastrophic complication of transcatheter aortic valve implantation (TAVI). Chimney stenting (CS) is one of the direct preventive measures for CO; however, data on its clinical course and characteristics are limited. We evaluated mid- to long-term outcomes of prophylactic CS during TAVI using supra-annular self-expanding bioprostheses. Methods and Results: Among 315 consecutive TAVI procedures with supra-annular self-expanding valves between November 2015 and April 2022, 14 patients at high risk for CO underwent prophylactic CS. The clinical outcomes of the CS group were investigated using a non-CS group (n=301) as a comparison reference. High-risk anatomy was identified by preprocedural computed tomography assessing the sinotubular junction, sinus of Valsalva, coronary height, and annular calcification. CS was performed when balloon aortic valvuloplasty with simultaneous aortography demonstrated absent coronary opacification or impending obstruction. Patients in the CS group were predominantly female with a smaller body size, smaller aortic root dimensions, and low left coronary height (9.6 vs. 12.5 mm; P<0.001). Dual antiplatelet therapy was administered in 93% of CS patients for a mean duration of 7.4 months. During a mean follow up of 4.3 years, mortality was similar to that of non-CS patients (log-rank P=0.756). Conclusions: The clinical outcomes of prophylactic chimney stenting were comparable with the conventional TAVI cohort; therefore, it may be considered a therapeutic option for patients at high risk of CO during supra-annular self-expanding TAVI.

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