Paediatric aortic valve replacement: a meta-analysis and microsimulation study

Abstract

Aims: To support decision-making in children undergoing aortic valve replacement (AVR), by providing a comprehensive overview of published outcomes after paediatric AVR, and microsimulation-based age-specific estimates of outcome with different valve substitutes.

Methods and results: A systematic review of published literature reporting clinical outcome after paediatric AVR (mean age <18 years) published between 1/1/1990 and 11/08/2021 was conducted. Publications reporting outcome after paediatric Ross procedure, mechanical AVR (mAVR), homograft AVR (hAVR), and/or bioprosthetic AVR were considered for inclusion. Early risks (<30d), late event rates (>30d) and time-to-event data were pooled and entered into a microsimulation model. Sixty-eight studies, of which one prospective and 67 retrospective cohort studies, were included, encompassing a total of 5259 patients (37 435 patient-years; median follow-up: 5.9 years; range 1-21 years). Pooled mean age for the Ross procedure, mAVR, and hAVR was 9.2 ± 5.6, 13.0 ± 3.4, and 8.4 ± 5.4 years, respectively. Pooled early mortality for the Ross procedure, mAVR, and hAVR was 3.7% (95% CI, 3.0%-4.7%), 7.0% (5.1%-9.6%), and 10.6% (6.6%-17.0%), respectively, and late mortality rate was 0.5%/year (0.4%-0.7%/year), 1.0%/year (0.6%-1.5%/year), and 1.4%/year (0.8%-2.5%/year), respectively. Microsimulation-based mean life-expectancy in the first 20 years was 18.9 years (18.6-19.1 years) after Ross (relative life-expectancy: 94.8%) and 17.0 years (16.5-17.6 years) after mAVR (relative life-expectancy: 86.3%). Microsimulation-based 20-year risk of aortic valve reintervention was 42.0% (95% CI: 39.6%-44.6%) after Ross and 17.8% (95% CI: 17.0%-19.4%) after mAVR.

Conclusion: Results of paediatric AVR are currently suboptimal with substantial mortality especially in the very young with considerable reintervention hazards for all valve substitutes, but the Ross procedure provides a survival benefit over mAVR. Pros and cons of substitutes should be carefully weighed during paediatric valve selection.

Keywords: Aortic valve; Aortic valve replacement; Congenital heart disease; Microsimulation.

Structured Graphical Abstract

Summary of clinical outcome after paediatric aortic valve replacement (AVR) with a pulmonary autograft (Ross procedure), mechanical prosthesis, or homograft.

Figure 1

Flowchart of study selection. * The total number of publications (n = 68) includes three publications from which only Kaplan–Meier curves were used. Baseline characteristics and outcome estimates of these publications are not provided due to overlapping study populations with other publications included in this meta-analysis.

Figure 2

A. Pooled Kaplan–Meier freedom from all-cause mortality after the Ross procedure. (B) Pooled Kaplan–Meier freedom from all-cause mortality after mechanical AVR. (C) Pooled Kaplan–Meier freedom from all-cause mortality after homograft AVR. (D) Pooled Kaplan–Meier freedom from autograft (LVOT) reintervention after the Ross procedure. (E) Pooled Kaplan–Meier freedom from homograft (RVOT) reintervention after the Ross procedure. (F) Pooled Kaplan–Meier freedom from any aortic valve-related reintervention after mechanical AVR.

Figure 3

Microsimulation-based age-specific life expectancy and 20-year risks of valve-related morbidity after mechanical aortic valve replacement and the ross procedure. Included error bars represent 95% credible intervals. SVD indicates structural valve deterioration and NSVD indicates non-SVD.

Figure 4

Microsimulation-based life expectancy after mechanical aortic valve replacement (<18 years) and the Ross procedure (<18 years and <1 year) compared with the age-, origin-, and sex-matched general population. Included error bars represent 95% credible intervals. (A) Life expectancy in children aged <18 years (Ross procedure and mechanical aortic valve replacement). (B) Life expectancy in infants aged <18 years at time of the Ross procedure.