Moderate Mitral StenosisMITIGATENCT01406353
Early Percutaneous Mitral Intervention in Asymptomatic Moderate Mitral Stenosis
A study testing Percutaneous Mitral Commissurotomy in people with Moderate Mitral Stenosis, run by Asan Medical Center at 3 sites in South Korea.
Trial summary
Although percutaneous mitral commissurotomy (PMC) has been accepted as an effective treatment for symptomatic patients with moderate or severe mitral stenosis (MS), most asymptomatic patients are not candidates for PMC owing to the small but inherent procedure-related risks. Read more about this study
- Who is it for?
- Ages 20 to 70 years
- Conditions the study is for
- Moderate Mitral Stenosis
- What is being tested?
- Percutaneous Mitral Commissurotomy
- Type of treatment
- Surgery or procedure
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 167 participants
- Where
- 3 sitesSouth Korea
- Study dates
- 29 Jul 2011to May 2026
- Phase
- Interventional
- Are there results?
- Not yet: the study is under way
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 20 to 70 years
- All sexes
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- asymptomatic patients with moderate MS who are potential candidates for early percutaneous mitral commissurotomy
Who cannot join
- patients with exertional dyspnea
- total echocardiographic score > 10
- moderate to severe mitral regurgitation
- left atrial thrombi
- significant aortic valve disease,
- left ventricle (LV) ejection fraction (EF) <50%
- Doppler-estimated pulmonary artery systolic pressure >50 mmHg
- those who were not candidates for early intervention based on age > 70 years or the presence of coexisting malignancies
Trial locations and contacts
3 sites in 1 country.
South Korea3 sites
Asan Medical Center
Seoul, 138-736
Samsung Medical Center
Seoul
Yonsei University Severance Hospital
Seoul
About this study
Official title: Early Percutaneous Mitral Intervention Versus Conventional Management in Asymptomatic Moderate Mitral Stenosis
Although percutaneous mitral commissurotomy (PMC) has been accepted as an effective treatment for symptomatic patients with moderate or severe mitral stenosis (MS), most asymptomatic patients are not candidates for PMC owing to the small but inherent procedure-related risks. Asymptomatic patients with MS show good survival rates up to 10 years, but there was a sudden deterioration precipitated by atrial fibrillation or embolism in half of the patients. Because the success rates of PMC were improved to more than 95% in ideal patients from highly selected centers and early PMC may decrease the occurrence of adverse events, such as atrial fibrillation or embolism, experienced centers tend to perform PMC at an early stage of disease. However, the potential benefits of early preemptive PMC in asymptomatic patients should be balanced against the real risks related to the procedure, and further studies of the efficacy of PMC in the prevention of embolism are necessary to extend its indications to asymptomatic patients. To the best of our knowledge, No randomized trials have been performed to ascertain the optimal timing of intervention in asymptomatic patients with significant MS. The early percutaneous MITral Intervention versus conventional manaGement in Asymptomatic moderate miTral stEnosis (MITIGATE) trial was designed to compare clinical outcomes of early intervention with those of a conventional management based on current guidelines in asymptomatic moderate mitral stenosis.
Read the detailed description
We enroll consecutive asymptomatic patients with moderate mitral stenosis who are candidates for both early percutaneous mitral commissurotomy (PMC) and conventional treatment at 3 centers in Seoul, Korea.
Echocardiographic evaluation is performed before enrollment, immediately after PMC and annually during follow-up. All patients undergo two-dimensional echocardiography and/or transesophageal echocardiography to detect left atrial thrombi. Morphologic features of the mitral valve (MV) are categorized as described previously (14), and total echocardiographic score is obtained by adding the scores for leaflet mobility, thickness, calcification, and subvalvular lesions. The MVA is measured by direct planimetry of the mitral orifice, and MS severity is graded as mild, moderate, or severe when MVA was > 1.5, 1.0 to 1.5, or < 1.0 cm2, respectively. The severity of mitral and tricuspid regurgitation is assessed semiquantitatively or using quantitative methods and classified as mild, moderate, or severe. Pulmonary artery systolic pressure (PAP) is estimated by continuous wave Doppler with the simplified Bernoulli equation.
All study patients regularly visit their attending physicians at 3 monthly interval for maintenance of anticoagulation therapy or every year for annual re-evaluation. Patients in the conventional treatment group who become symptomatic during follow-up are referred for PMC or mitral valve surgery. An embolic event is defined as a systemic embolism fulfilling both prespecified criteria: acute onset of clinical symptoms or signs of embolism and occurrence of new lesions confirmed by imaging studies. A specific diagnosis of cerebral infarction is confirmed by an experienced neurologist and additional brain magnetic resonance imaging is performed if indicated.
We estimate that a sample size of 166 patients would provide 80% power to detect a significant difference with respect to the primary end point at the 2-sided significance level of 0.05, assuming 3-year event rates of 13% in the conventional treatment group and 2% in the early PMC group, and drop-out rate of 5%. These rates are based on the results of our previous study. Analyses are performed on an intention-to-treat basis. To analyze primary outcome, estimates of cumulative event rates are calculated by the Kaplan-Meier method and compared employing the log-rank test. For Kaplan-Meier analysis, we analyze all clinical events by time to first event. Hazard ratios with 95% confidence intervals are derived with the use of the Cox proportional hazards model.
- Conditions
- Moderate Mitral Stenosis
- Being tested
- Percutaneous Mitral Commissurotomy
- Keywords
- Mitral Stenosis, Mitral Valvuloplasty
- Medical subject headings
- Mitral Valve Stenosis
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Percutaneous Mitral CommissurotomyProcedure or surgery
Also called Percutaneous mitral valvuloplasty
Percutaneous mitral commissurotomy is performed by experienced interventional cardiologists using the Inoue balloon technique. During the procedure, conventional hemodynamic parameters are monitored. A successful immediate result is defined as a mitral valve area > 1.5 square cm with less than moderate to severe mitral regurgitation.
| Study group | Role | What they receive |
|---|---|---|
| Early Percutaneous Mitral Intervention | Active comparator | early elective percutaneous mitral commissurotomy within 3 months of enrollment Receives: Procedure: Percutaneous Mitral Commissurotomy |
| Conventional Treatment | No intervention | All patients in the conventional treatment group regularly visit their attending physicians at 3 monthly interval for maintenance of anticoagulation therapy or every year for annual re-evaluation. Patients who become symptomatic during follow-up are referred for percutaneous mitral commissurotomy or mitral valve surgery. |
What is being measured
The primary outcome is the main question the study is designed to answer.
Composite of cardiovascular event
Composite of cardiovascular mortality, cerebral infarction, systemic embolic events that occurred during follow-up, and PMC-related complications; procedural mortality and urgent MV surgery.
Measured: Participants will be followed for the duration of the trial, a minimum follow-up of 10 years
Secondary outcomes (2)
all-cause death and each component of cardiovascular event
all-cause death and any component of composite primary end point.
Measured: Participants will be followed for the duration of the trial, a minimum follow-up of 10 years
Mitral valve replacement
Measured: Participants will be followed for the duration of the trial, a minimum follow-up of 10 years
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted1 Aug 2011 (estimated)
- Study start29 Jul 2011
- Primary completionMay 2026 (estimated)
- Study completionMay 2026 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Publications (2)Papers the sponsor has linked to this study.
- Other trials for Moderate Mitral StenosisStudies of the same condition, open and under way.
- More trials run by Asan Medical CenterThe sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Model description
- early percutaneous mitral commissurotomy
- Masking
- None (open label)
- Enrolment
- 167 participants (actual)
Sponsor and investigators
- Lead sponsor
- Asan Medical Center
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, Duk-Hyun Kang, Asan Medical Center
- Investigators
- Duk-Hyun Kang, MD, PhD, Principal investigator, Asan Medical Center
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT01406353
- Sponsor's protocol ID
- 2011-0432
- Acronym
- MITIGATE
- Status last verified
- Nov 2025
- First submitted
- 28 Jul 2011
- Last updated
- 17 Nov 2025
- Results posted
- No
- Data monitoring committee
- Yes
Publications
Kang DH, Lee CH, Kim DH, Yun SC, Song JM, Lee CW, Song JK, Park SW, Park SJ. Early percutaneous mitral commissurotomy vs. conventional management in asymptomatic moderate mitral stenosis. Eur Heart J. 2012 Jun;33(12):1511-7. doi: 10.1093/eurheartj/ehr495. Epub 2012 Jan 13.
PubMed 22246444Kang DH, Park SJ, Lee SA, Lee S, Kim DH, Park DW, Yun SC, Hong GR, Song JM, Hong MK, Park SW, Park SJ. Early percutaneous mitral commissurotomy or conventional management for asymptomatic mitral stenosis: a randomised clinical trial. Heart. 2021 Dec;107(24):1980-1986. doi: 10.1136/heartjnl-2021-319857. Epub 2021 Sep 15.
PubMed 34526318
Study at a glance
From the registry record, last updated by the sponsor on 17 Nov 2025. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Early Percutaneous Mitral Intervention Versus Conventional Management in Asymptomatic Moderate Mitral Stenosis
- ClinicalTrials.gov ID
- NCT01406353
- Acronym / sponsor ID
- MITIGATE / 2011-0432
- Conditions
- Moderate Mitral Stenosis
- Keywords
- Mitral Stenosis, Mitral Valvuloplasty
- Study type
- Interventional
- Recruitment status
- Active, not recruiting
- Enrolment
- 167 participants (actual)
- Lead sponsor
- Asan Medical CenterUniversity, hospital or other
- Study start
- 29 Jul 2011 (actual)
- Primary completion
- May 2026 (estimated)
- Study completion
- May 2026 (estimated)
- First posted
- 1 Aug 2011 (estimated)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
Although percutaneous mitral commissurotomy (PMC) has been accepted as an effective treatment for symptomatic patients with moderate or severe mitral stenosis (MS), most asymptomatic patients are not candidates for PMC owing to the small but inherent procedure-related risks. Asymptomatic patients with MS show good survival rates up to 10 years, but there was a sudden deterioration precipitated by atrial fibrillation or embolism in half of the patients. Because the success rates of PMC were improved to more than 95% in ideal patients from highly selected centers and early PMC may decrease the occurrence of adverse events, such as atrial fibrillation or embolism, experienced centers tend to perform PMC at an early stage of disease. However, the potential benefits of early preemptive PMC in asymptomatic patients should be balanced against the real risks related to the procedure, and further studies of the efficacy of PMC in the prevention of embolism are necessary to extend its indications to asymptomatic patients. To the best of our knowledge, No randomized trials have been performed to ascertain the optimal timing of intervention in asymptomatic patients with significant MS. The early percutaneous MITral Intervention versus conventional manaGement in Asymptomatic moderate miTral stEnosis (MITIGATE) trial was designed to compare clinical outcomes of early intervention with those of a conventional management based on current guidelines in asymptomatic moderate mitral stenosis.
Detailed description
We enroll consecutive asymptomatic patients with moderate mitral stenosis who are candidates for both early percutaneous mitral commissurotomy (PMC) and conventional treatment at 3 centers in Seoul, Korea.
Echocardiographic evaluation is performed before enrollment, immediately after PMC and annually during follow-up. All patients undergo two-dimensional echocardiography and/or transesophageal echocardiography to detect left atrial thrombi. Morphologic features of the mitral valve (MV) are categorized as described previously (14), and total echocardiographic score is obtained by adding the scores for leaflet mobility, thickness, calcification, and subvalvular lesions. The MVA is measured by direct planimetry of the mitral orifice, and MS severity is graded as mild, moderate, or severe when MVA was > 1.5, 1.0 to 1.5, or < 1.0 cm2, respectively. The severity of mitral and tricuspid regurgitation is assessed semiquantitatively or using quantitative methods and classified as mild, moderate, or severe. Pulmonary artery systolic pressure (PAP) is estimated by continuous wave Doppler with the simplified Bernoulli equation.
All study patients regularly visit their attending physicians at 3 monthly interval for maintenance of anticoagulation therapy or every year for annual re-evaluation. Patients in the conventional treatment group who become symptomatic during follow-up are referred for PMC or mitral valve surgery. An embolic event is defined as a systemic embolism fulfilling both prespecified criteria: acute onset of clinical symptoms or signs of embolism and occurrence of new lesions confirmed by imaging studies. A specific diagnosis of cerebral infarction is confirmed by an experienced neurologist and additional brain magnetic resonance imaging is performed if indicated.
We estimate that a sample size of 166 patients would provide 80% power to detect a significant difference with respect to the primary end point at the 2-sided significance level of 0.05, assuming 3-year event rates of 13% in the conventional treatment group and 2% in the early PMC group, and drop-out rate of 5%. These rates are based on the results of our previous study. Analyses are performed on an intention-to-treat basis. To analyze primary outcome, estimates of cumulative event rates are calculated by the Kaplan-Meier method and compared employing the log-rank test. For Kaplan-Meier analysis, we analyze all clinical events by time to first event. Hazard ratios with 95% confidence intervals are derived with the use of the Cox proportional hazards model.
Study design
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- None (open label)
- Number of arms
- 2
- Model description
- early percutaneous mitral commissurotomy
| Arm | Type | Receives |
|---|---|---|
| Early Percutaneous Mitral Intervention | Active comparator | Procedure: Percutaneous Mitral Commissurotomyearly elective percutaneous mitral commissurotomy within 3 months of enrollment |
| Conventional Treatment | No intervention | –All patients in the conventional treatment group regularly visit their attending physicians at 3 monthly interval for maintenance of anticoagulation therapy or every year for annual re-evaluation. Patients who become symptomatic during follow-up are referred for percutaneous mitral commissurotomy or mitral valve surgery. |
Who may qualify
- Ages
- 20 to 70 years
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (1 listed)
- asymptomatic patients with moderate MS who are potential candidates for early percutaneous mitral commissurotomy
Key exclusion criteria (8 listed)
- patients with exertional dyspnea
- total echocardiographic score > 10
- moderate to severe mitral regurgitation
- left atrial thrombi
- significant aortic valve disease,
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Percutaneous Mitral CommissurotomyAlso: Percutaneous mitral valvuloplastyPercutaneous mitral commissurotomy is performed by experienced interventional cardiologists using the Inoue balloon technique. During the procedure, conventional hemodynamic parameters are monitored. A successful immediate result is defined as a mitral valve area > 1.5 square cm with less than moderate to severe mitral regurgitation. | Procedure or surgery | Early Percutaneous Mitral Intervention |
Primary outcome
Composite of cardiovascular event
Time frame: Participants will be followed for the duration of the trial, a minimum follow-up of 10 years
Composite of cardiovascular mortality, cerebral infarction, systemic embolic events that occurred during follow-up, and PMC-related complications; procedural mortality and urgent MV surgery.
2 secondary outcomes
all-cause death and each component of cardiovascular event
Time frame: Participants will be followed for the duration of the trial, a minimum follow-up of 10 years
Mitral valve replacement
Time frame: Participants will be followed for the duration of the trial, a minimum follow-up of 10 years
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 17 Nov 2025.
- Background: PubMed 22246444Kang DH, Lee CH, Kim DH, Yun SC, Song JM, Lee CW, Song JK, Park SW, Park SJ. Early percutaneous mitral commissurotomy vs. conventional management in asymptomatic moderate mitral stenosis. Eur Heart J. 2012 Jun;33(12):1511-7. doi: 10.1093/eurheartj/ehr495. Epub 2012 Jan 13.
- Derived from this study: PubMed 34526318Kang DH, Park SJ, Lee SA, Lee S, Kim DH, Park DW, Yun SC, Hong GR, Song JM, Hong MK, Park SW, Park SJ. Early percutaneous mitral commissurotomy or conventional management for asymptomatic mitral stenosis: a randomised clinical trial. Heart. 2021 Dec;107(24):1980-1986. doi: 10.1136/heartjnl-2021-319857. Epub 2021 Sep 15.
Related trials for Moderate Mitral Stenosis
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Impact of Automatic Prompts in Echocardiographic Reports on Referral to Cardiology
Mitral Regurgitation (MR), Moderate or Severe Aortic Stenosis (AS) (Mean Pressure Gradient ≥ 20 mm Hg or Aortic Valve Area ≤ 1.5 cm2)
Recruiting
Early Versus Deferred Aortic Valve Replacement in Patients With Moderate Aortic Stenosis and Mitral Regurgitation
Aortic Valve Replacement in Patients With Moderate Aortic Stenosis Combined With Mitral Regurgitation
Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
Duk-Hyun Kang, MD, PhD principal investigator
Asan Medical Center
3 sites in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing Percutaneous Mitral Commissurotomy in people with Moderate Mitral Stenosis, run by Asan Medical Center at 3 sites in South Korea.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 1 inclusion and 8 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: under way, not looking for participants, as of the sponsor's last update on 17 Nov 2025. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 3 sites in South Korea. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Composite of cardiovascular event (time frame: Participants will be followed for the duration of the trial, a minimum follow-up of 10 years). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
On the ClinicalTrials.gov record for NCT01406353, which also lists 2 linked publications.
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 17 Nov 2025.