A Prospective Multicenter Cohort Study on Surgical Treatment Strategies for Pediatric Mitral Regurgitation

This prospective, multicenter cohort study aims to evaluate the outcomes of surgical repair for pediatric mitral regurgitation (MR) in China. From March 2020 to December 2024, consecutive patients younger than 14 years who underwent mitral valve repair at eight representative congenital heart disease centers were enrolled. Eligible patients were those with at least moderate MR on preoperative echocardiography and no prior mitral valve surgery. Patients with uncorrectable concomitant cardiac anomalies, moderate or greater mitral stenosis, ischemic MR, severe leaflet dysplasia, connective tissue disorders (e.g., Barlow, Marfan), cardiomyopathies, or single-ventricle physiology were excluded.

The primary endpoint is a composite of all-cause mortality, reoperation for cardiovascular causes, or recurrence of moderate-or-severe MR during follow-up. Secondary endpoints include perioperative outcomes such as postoperative hospital stay, intensive care unit stay, mechanical ventilation time, and hospitalization cost.

This study is designed to provide high-quality prospective evidence on the safety, durability, and predictors of surgical repair for pediatric MR in a contemporary, real-world, multicenter setting. The findings may inform surgical decision-making and postoperative management strategies for this rare but challenging population.

Study Overview

• Status: Completed
• Conditions: Pediatric Cardiac Surgery; Mitral Regurgitation (MR)
• Intervention / Treatment: Procedure: conventional mitral valve repair; Procedure: standardized mitral valve repair

• Study Type: Observational
• Enrollment (Actual): 427

Contacts and Locations

Study Locations

• China
  • Beijing Municipality
    • Beijing, Beijing Municipality, China, 100037
      • Pediatric Cardiac Surgery Center, Fuwai Hospital

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Child
• Accepts Healthy Volunteers: No

• Sampling Method: Non-Probability Sample

Study Population

Children younger than 14 years with moderate or greater mitral regurgitation undergoing surgical repair at eight representative congenital heart disease centers in China. Eligible patients must not have undergone prior mitral valve surgery and must meet the predefined inclusion and exclusion criteria. The study aims to prospectively evaluate surgical outcomes, durability, and predictors of repair from March 2020 to December 2024, with follow-up completed through September 2025.

Description

Inclusion Criteria:

• Age < 14 years
• No prior mitral valve surgery
• Preoperative echocardiography demonstrating moderate or severe mitral regurgitation

Exclusion Criteria:

• Concomitant cardiac malformations unable to be corrected simultaneously
• Moderate or severe mitral stenosis
• Ischemic mitral regurgitation
• Severe leaflet dysplasia precluding adequate coaptation
• Connective tissue disorders(e.g., Barlow's disease, Marfan syndrome)
• Any type of cardiomyopathy
• Single ventricle physiology or common atrioventricular valve

Study Plan

How is the study designed?

Number of groups / cohorts

2

Cohorts and Interventions

Group / Cohort	Intervention / Treatment
Conventional Group; Those who have undergone conventional mitral valve repair	Procedure: conventional mitral valve repair; Patients undergoing conventional mitral valve repair, including annuloplasty, leaflet cleft closure, chordal transfer, and chordal resection, et al.
Standardized Group; Those who have undergone standardized mitral valve repair	Procedure: standardized mitral valve repair; Patients undergoing the standardized mitral valve repair strategy proposed by Professor Li at Fuwai Hospital in 2016, which involves comprehensive exploration and correction of abnormalities at the subvalvular, leaflet, and annular levels.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Composite Primary Endpoint	Time-to-first event of any of the following: (a) all-cause mortality; (b) mitral valve reoperation; or (c) recurrence of ≥ moderate mitral regurgitation on transthoracic echocardiography.	From date of index surgery until last follow-up (up to 5 years)

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Postoperative Hospital Length of Stay	Total postoperative days from surgery to hospital discharge.	perioperatively
ICU Length of Stay	Consecutive time in intensive care unit.	perioperatively
Duration of Invasive Mechanical Ventilation	Cumulative duration of invasive mechanical ventilation during the index hospitalization, including all episodes of intubation and re-intubation.	perioperatively
Hospitalization Cost	Total in-hospital medical cost for the index surgical admission (local currency), extracted from billing records.	perioperatively

Collaborators and Investigators

• Sponsor: China National Center for Cardiovascular Diseases

Study record dates

Study Major Dates

• Study Start (Actual): March 18, 2020
• Primary Completion (Actual): September 20, 2025
• Study Completion (Actual): September 20, 2025

Study Registration Dates

• First Submitted: September 24, 2025
• First Submitted That Met QC Criteria: December 14, 2025
• First Posted (Actual): December 16, 2025

Study Record Updates

• Last Update Posted (Actual): December 16, 2025
• Last Update Submitted That Met QC Criteria: December 14, 2025
• Last Verified: December 1, 2025

More Information

Terms related to this study

• Keywords: Mitral Regurgitation; Surgical Outcomes; Mitral Valve Repair; Pediatric Cardiac Surgery
• Additional Relevant MeSH Terms: Cardiovascular Diseases; Heart Diseases; Heart Valve Diseases; Mitral Valve Insufficiency
• Other Study ID Numbers: 2020-FW-MR

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO
• IPD Plan Description: The data underlying this article cannot be shared publicly for the privacy of individuals that participated in the study.

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No