LEFT ATRIAL MONITORING IN PATIENTS BEFORE AND AFTER MITRAL SURGERY - LAMBDA STUDY (LAMBDA)

Mitral valve leakage, or mitral regurgitation (MR), is associated with heart failure symptoms including shortness of breath, fatigue, irregular heart rate. When left untreated, it may cause death. Patients with MR can be divided in two broad groups: those with primary MR, caused by disease of the mitral valve structures, and those with secondary MR, due to dilation of the heart chambers. Our study focuses on patients with primary MR.

The standard treatment for severe symptomatic primary MR is mitral valve surgery, a type of open-heart surgery. The outcomes following this procedure are excellent, however, a subset of patients continue to experience heart failure symptoms after surgery due to very high pressures in the heart, more specifically in the left atrium, which is one of the four heart chambers. This is called functional mitral stenosis (FMS).

Previous studies have shown that creating a small opening between the left and right atria can help relieve the pressure inside the left atrium. We would like to determine whether creating this opening between the two atria at the time of mitral valve surgery can help prevent FMS. To answer this question, we will study two groups of patients who need mitral valve surgery for primary MR. The first group will undergo mitral valve surgery, along with the creation of the opening between the two atria. The second group will undergo mitral valve surgery alone. We will then compare the outcomes between both groups, namely with regards to their heart failure symptoms after open-heart surgery.

Study Overview

• Status: Not yet recruiting
• Conditions: Heart Failure; Mitral Regurgitation; Mitral Valve Disease
• Intervention / Treatment: Other: Mitral valve repair with creation of an 8 mm inter-atrial shunt

• Study Type: Interventional
• Enrollment (Estimated): 50
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Kenza Rahmouni El Idrissi, Dr.; Phone Number: 613-696-7000; Email: krahmouni@ottawaheart.ca
• Study Contact Backup: Name: Alice Black; Phone Number: 613-696-7230; Email: alblack@ottawaheart.ca

Study Locations

• Canada
  • Ontario
    • Ottawa, Ontario, Canada, K1Y 4W7
      • University of Ottawa Heart Institute
      • Contact: Alice Black; Phone Number: 613-696-7230; Email: alblack@ottawaheart.ca
      • Contact: Kenza Rahmouni, Dr.; Email: krahmouni@ottawaheart.ca

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Patients ≥18 years of age
• Severe (4+) symptomatic Carpentier Type II MR due to degenerative disease
• Planned surgical mitral valve repair
• Right-to-left atrial pressure gradient ≥ 5 mmHg at baseline
• Pulmonary vascular resistance ≤ 4 Wood units

Exclusion Criteria:

• Secondary causes of MR and mixed mitral valve disease
• Infective endocarditis within 30-days
• Any prior mitral valve intervention
• Need for emergency intervention or surgery
• Left ventricular ejection fraction 2+

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Single

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Mitral valve repair with creation of an 8m inter-atrial shunt	Other: Mitral valve repair with creation of an 8 mm inter-atrial shunt; Mitral valve repair with creation of an 8 mm inter-atrial shunt
Active Comparator: Mitral valve repair without a shunt	Other: Mitral valve repair with creation of an 8 mm inter-atrial shunt; Mitral valve repair with creation of an 8 mm inter-atrial shunt

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Feasibility: recruitment rate	Process, Resources, Management, Scientific	30 Months
Feasibility: Success rate of intervention	Process, Resources, Management, Scientific	30 Months
Feasibility: Study follow-up rate and length	Process, Resources, Management, Scientific	30 Months

Collaborators and Investigators

• Sponsor: Ottawa Heart Institute Research Corporation
• Investigators: Principal Investigator: Vincent Chan, Dr., Ottawa Heart Institute Research Corporation

Study record dates

Study Major Dates

• Study Start (Estimated): September 30, 2026
• Primary Completion (Estimated): January 31, 2028
• Study Completion (Estimated): January 31, 2030

Study Registration Dates

• First Submitted: August 7, 2024
• First Submitted That Met QC Criteria: August 7, 2024
• First Posted (Actual): August 9, 2024

Study Record Updates

• Last Update Posted (Actual): May 6, 2026
• Last Update Submitted That Met QC Criteria: April 29, 2026
• Last Verified: April 1, 2026

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Cardiovascular Diseases; Heart Diseases; Heart Valve Diseases; Heart Failure; Mitral Valve Insufficiency
• Other Study ID Numbers: 20240059

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

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