Sources and Guidelines Referenced

The clinical evidence and diagnostic protocols referenced in this guide are derived from major international cardiovascular clinical practice guidelines and milestone clinical trials, including: the ACC/AHA Guideline for the Management of Patients With Valvular Heart Disease (2020), the ESC/EACTS Guidelines for the management of valvular heart disease (2021), the COAPT Trial (Stone et al., New England Journal of Medicine, 2018), the EVEREST II Trial (Feldman et al., New England Journal of Medicine, 2011), the MITRA-FR Trial (Obadia et al., New England Journal of Medicine, 2018), and the STS/ACC TVT Registry Analysis (Mack et al., Journal of the American College of Cardiology, 2021).

MitraClip (Transcatheter Mitral Repair): A Comprehensive Patient Guide

1. Definition and Medical Identity

MitraClip (Transcatheter Mitral Repair) is a minimally invasive percutaneous structural heart procedure that fixes a leaking mitral valve without open-heart surgery. Clinically categorized as transcatheter edge-to-edge repair (TEER), this intervention uses a mechanical clip to join the center of the valve's leaflets, reducing mitral regurgitation and restoring normal forward blood flow.

Anatomical Context and Classification

The procedure belongs to the subspecialty of interventional cardiology. It adapts the open surgical technique developed by Dr. Ottavio Alfieri into a catheter-based therapy. Rather than cutting through the chest bone, interventional cardiologists access the heart through a blood vessel in the leg. The fundamental goal of the procedure is to decrease backward blood flow into the lungs, relieve debilitating heart failure symptoms, prevent recurrent hospitalizations, and improve long-term survival in eligible patients.

2. The Underlying Condition or Need

Mitral regurgitation (MR) is a structural cardiac disorder where the mitral valve fails to close tightly during ventricular contraction, allowing blood to leak backward into the left atrium. This mechanical failure disrupts normal cardiovascular circulation, increasing pressure in the pulmonary vessels and reducing the net volume of oxygen-rich blood pumped to the rest of the body.

Pathophysiology and Natural Trajectory

Under healthy conditions, the mitral valve acts as a one-way door between the left atrium (upper chamber) and left ventricle (lower chamber). When the left ventricle contracts, high intraventricular pressure closes the two valve leaflets—the anterior leaflet and posterior leaflet. In mitral regurgitation, incomplete closure causes a fraction of the stroke volume to flow backward (the regurgitant volume).

Mitral regurgitation is broadly categorized into two main types:

• Primary (Degenerative) Mitral Regurgitation: Caused by an intrinsic physical defect in the valve apparatus itself, such as myxomatous degeneration, leaflet prolapse (flail leaflet), or rupture of the supporting chordae tendineae.
• Secondary (Functional) Mitral Regurgitation: Caused by underlying disease of the left ventricle (such as an enlarged heart from prior heart attacks or dilated cardiomyopathy). The valve leaflets are structurally normal, but physical stretching of the heart muscle pulls the leaflets apart (tethering), preventing them from meeting in the middle.

If left untreated, severe mitral regurgitation triggers progressive cardiac remodeling. The left ventricle dilates to accommodate the extra volume, leading to elevated left atrial pressures, pulmonary hypertension, atrial fibrillation, congestive heart failure, and elevated mortality (ACC/AHA Valvular Heart Disease Guidelines, 2020).

3. How the Treatment Works — Mechanism

Transcatheter edge-to-edge repair works by mechanically clipping the free edges of the mitral valve leaflets together at the exact site of the regurgitant jet. This mechanical connection creates a permanent bridge of tissue, transforming the single large, leaking valve opening into a functional double-orifice valve during diastole while ensuring full closure during systole.

Cellular and Mechanical Principles

The fundamental mechanism relies on mechanical approximation and subsequent tissue integration. When the device grasps both the anterior and posterior leaflets, it eliminates the gap (coaptation defect) through which blood leaks backward.

Over weeks to months following implantation, the body responds to the presence of the metallic implant through a biological process called endothelialization. Endothelial cells grow over the device, encasing the clip in natural cardiovascular tissue. This structural bridge secures the connection between the leaflets, stabilizes valve mechanics, and reduces mechanical shear stress on the valve structures. By eliminating the high-pressure backward leakage, transcatheter repair immediately reduces left atrial volume and pressure, lowering pulmonary capillary wedge pressure and alleviating breathlessness.

4. Types and Variations

Transcatheter edge-to-edge repair systems have evolved through multiple technological generations, offering various clip sizes and independent grasping capabilities to accommodate diverse valve anatomies. Modern clip systems allow operators to tailor the size, width, and control mechanisms of the implant to the specific structural shape of the patient's valve defect.

Device Generation Comparison

Current Fourth-Generation (G4) systems feature four distinct clip size options and independent leaflet control, allowing clinicians to grasp each leaflet separately if complex movement or anatomical asymmetry is present (Kar et al., EXPAND Study, 2021).

Device Variant / Size	Arm Length	Clip Width	Primary Anatomical Indication
Standard / NT	9.0 mm	4.0 mm	Standard leaflet tethering, narrow grasping zones, classical central jets.
NTW (Wide)	9.0 mm	6.0 mm	Broad regurgitant jets, wide coaptation gaps requiring broader mechanical coverage.
XT	12.0 mm	4.0 mm	Redundant leaflet tissue, deep coaptation gaps, severe leaflet prolapse or flail gap.
XTW (Extra Wide)	12.0 mm	6.0 mm	Large dilated rings with broad jets and severe tethering needing maximal leaflet engagement.

Clinicians determine the appropriate clip selection using pre-procedural 3D transesophageal echocardiography (3D-TEE). Larger clips engage more tissue but require sufficient valve area to prevent narrowing (stenosis), whereas narrower clips are preferred when the baseline valve area is smaller.

5. Who the Treatment Is For — Indications

Transcatheter edge-to-edge repair is indicated for patients with symptomatic, severe mitral regurgitation who meet specific anatomical criteria and are considered at elevated risk for conventional surgery. Eligibility is determined through formal multi-specialty evaluation by a multidisciplinary Structural Heart Team.

Clinical Indications and Thresholds

Clinical practice guidelines (ACC/AHA 2020; ESC/EACTS 2021) establish specific criteria for intervention across both disease types:

• Primary (Degenerative) Mitral Regurgitation: Indicated for patients with symptomatic severe (Grade 3+ or 4+) primary MR who are deemed to be at high or prohibitive risk for open surgical repair or replacement by a cardiac surgeon (predicted perioperative mortality risk ≥ 8% or presence of severe frailty/porcelain aorta).
• Secondary (Functional) Mitral Regurgitation: Indicated for patients with persistent, severe symptomatic secondary MR (Grade 3+ or 4+) despite maximal, optimized guideline-directed medical therapy (GDMT), provided they meet trial-proven anatomical thresholds (COAPT Trial, Stone et al., 2018):
  • Left ventricular ejection fraction (LVEF) between 20% and 50%.
  • Left ventricular end-systolic dimension (LVESD) ≤ 70 mm.
  • Documented residual severe regurgitation after maximum tolerated doses of heart failure medications (ARNIs/ACEi, beta-blockers, MRAs, SGLT2 inhibitors).

6. Who the Treatment Is NOT For — Contraindications

Transcatheter edge-to-edge repair is contraindicated in patients who cannot tolerate anticoagulation, have active infections, or present with valve geometries that prevent safe clip placement. Attempting the procedure in unsuitable candidates carries a high risk of worsening valve function or vascular injury.

Absolute and Relative Contraindications

Category	Clinical Condition	Clinical Rationale
Absolute Contraindications	Active Endocarditis / Infection	High risk of device infection and destruction of valve tissue.
Absolute Contraindications	Severe Mitral Stenosis	Baseline valve area < 4.0 cm² creates prohibitive risk of severe mechanical airway obstruction/stenosis post-clip.
Absolute Contraindications	Intracardiac Thrombus	High risk of systemic arterial embolization during catheter manipulation in left atrium.
Absolute Contraindications	Inability to Anticoagulate	Inability to tolerate intra-procedural heparin or post-procedural antiplatelet regimens.
Relative Contraindications	Severe Calcification of Grasp Zone	Prevents firm mechanical grip by clip grippers; risk of tissue tearing.
Relative Contraindications	Short Posterior Leaflet (< 7 mm)	Insufficient tissue depth for clip friction arms to reliably catch and retain leaflet.
Relative Contraindications	Inadequate Transseptal Access Route	Severe inferior vena cava occlusion or severe structural septal anomalies.

7. Alternatives and Clinical Comparison

Alternatives to transcatheter edge-to-edge repair include guideline-directed medical therapy, open surgical repair or replacement, and emerging transcatheter mitral valve replacement options. The choice between options depends on the underlying mechanism of regurgitation, surgical risk, and anatomical feasibility.

Treatment Modality Comparison

technique-dependent; potential residual grade 1-2+ MR; requires strict anatomy.Does not fix physical leaflet defects; progressive disease trajectory.High procedural risk in elderly/frail; requires cardiopulmonary bypass.Requires long-term anticoagulation (mechanical) or risk of structural degradation (bioprosthetic).High risk of left ventricular outflow tract (LVOT) obstruction; early clinical trial phase.

Treatment Option	Mechanism	Invasiveness	Primary Advantages	Key Trade-Offs / Limitations
MitraClip (TEER)	Percutaneous edge-to-edge leaflet clipping.	Minimally Invasive (Femoral vein access).	No sternotomy; fast recovery; safe in high-risk patients.
Guideline-Directed Medical Therapy (GDMT)	Neurohormonal blockade (ARNIs, SGLT2i, Beta-blockers).	Non-invasive (Oral medications).	Treats baseline heart failure; no procedural risk.
Surgical Mitral Repair	Annuloplasty ring placement + leaflet resection.	Highly Invasive (Median sternotomy / thoracotomy).	Gold standard durability for primary MR; near-zero residual MR.
Surgical Mitral Replacement	Excision of valve and mechanical/bioprosthetic valve insertion.	Highly Invasive (Open surgery).	Completely eliminates regurgitation regardless of valve shape.
Transcatheter Valve Replacement (TMVR)	Percutaneous bioprosthetic valve deployment.	Minimally / Moderately Invasive.	Eliminates regurgitation without open surgery.

8. Pre-Treatment Phase

The pre-treatment phase focuses on confirming anatomical suitability through specialized cardiac imaging and optimizing medical management. This phase ensures that every candidate receives the safest, most effective individualized treatment plan.

Diagnostic Workup and Consultation

The patient undergoes an evaluation by the multidisciplinary Heart Team, consisting of structural interventional cardiologists, cardiac surgeons, imaging cardiologists, and heart failure specialists. Essential diagnostics include:

• Multiplanar Transesophageal Echocardiography (TEE): The core diagnostic tool used to measure leaflet length, coaptation depth, coaptation length, flail width, flail gap, and baseline mitral valve area.
• Transthoracic Echocardiography (TTE): Assesses overall left ventricular ejection fraction, cardiac chamber dimensions, and right ventricular systolic pressure.
• Coronary Angiography: Evaluates underlying coronary artery disease to determine if percutaneous coronary intervention (PCI) is needed before valve repair.
• Computed Tomography (CT) Vascular Mapping: Evaluates the pelvic and femoral veins to ensure sheath insertion can be performed safely.

Patients are instructed on medication adjustments—specifically holding short-acting oral anticoagulants or converting to low-molecular-weight heparin according to institutional electrophysiology guidelines—and must fast for 8 hours prior to the procedure.

9. The Procedure — Step-by-Step Clinical Detail

Transcatheter edge-to-edge repair is performed in a specialized hybrid operating room or cardiac catheterization laboratory under general anesthesia using continuous 3D-TEE and fluoroscopy guidance. The entire procedure typically takes between 1.5 and 3 hours.

Chronological Step-by-Step Overview

1. Vascular Access: The interventional cardiologist obtains percutaneous access to the right femoral vein using ultrasound guidance. A large-bore introducer sheath is inserted.
2. Transseptal Puncture: Under real-time TEE guidance, a specialized needle is advanced from the inferior vena cava into the right atrium and driven across the interatrial septum into the left atrium at a precise height (typically 4.0 to 4.5 cm above the mitral annular plane).
3. Steerable Guide Catheter Insertion: A high-flexibility steerable guide catheter (SGC) is advanced over a guidewire through the septum into the left atrium. Heparin is administered to maintain an activated clotting time (ACT) above 250–300 seconds.
4. Positioning the Delivery System: The Clip Delivery System (CDS) is navigated through the guide catheter. Using precise three-dimensional steering controls, the operator positions the clip directly over the center of the regurgitant jet, aligning the clip arms perpendicular to the leaflet coaptation line.
5. Crossing the Valve and Leaflet Grasping: The open clip is advanced across the mitral valve into the left ventricle during diastole. Upon slow retraction during systole, the operator uses internal friction grippers (Elastomer grippers) to catch the anterior and posterior valve leaflets simultaneously within the clip arms.
6. Echocardiographic Verification: TEE imaging confirms both leaflets are captured securely with adequate tissue bridges. Color Doppler verifies significant reduction in mitral regurgitation (target ≤ Grade 2+), while continuous hemodynamic monitoring confirms that the mean transvalvular gradient remains low (typically < 5 mmHg).
7. Deployment and Closure: Once optimal position and efficacy are verified, the clip is locked and detached from the catheter. If necessary, a second clip is deployed. The delivery system is withdrawn, heparin is reversed with protamine, and the femoral vein puncture site is sealed using percutaneous closure devices or figure-of-eight sutures.

10. Immediate Post-Procedure Period

During the first 24 hours, the patient is monitored in a cardiac intensive care or step-down unit to confirm groin site stability and maintain stable blood pressure. Bed rest is maintained for several hours to prevent access site bleeding.

First 24 to 48 Hours

Immediately following catheter removal, direct manual pressure or vascular closure systems secure the femoral venous access site. The patient remains flat on their back (supine) for 4 to 6 hours to prevent hematoma formation.

Key post-procedural protocols include:

• Continuous telemetry to detect potential atrial or ventricular arrhythmias.
• Serial groin evaluations to monitor for vascular complications or hematoma.
• Repeat transthoracic echocardiogram before discharge to re-evaluate clip stability, measure residual mitral regurgitation, and exclude pericardial effusion.
• Discharge criteria include stable vital signs, independent ambulation, absence of access-site bleeding, and stable renal function. Most patients meet these criteria within 24 to 48 hours.

11. Recovery — Short and Long Term

Recovery from transcatheter edge-to-edge repair is relatively rapid, with most patients returning to light daily activities within one week of the procedure. Long-term care focuses on antiplatelet therapy and serial cardiac imaging.

Recovery Timeline and Restrictions

• Days 1–7: Light household ambulation. Patients are instructed to avoid heavy lifting (>10 lbs), vigorous straining, or driving for 5 to 7 days to allow the femoral venous puncture site to heal.
• Weeks 2–4: Gradual restoration of normal daily routines. Patients may participate in structured cardiac rehabilitation programs tailored to their functional baseline.
• Medication Management: Patients typically receive single or dual antiplatelet therapy (such as aspirin and clopidogrel) for 1 to 6 months post-procedure to prevent thrombus formation on the implant. Patients with pre-existing atrial fibrillation remain on oral anticoagulants.
• Follow-up Schedule: Clinical evaluation and TTE imaging occur at 30 days, 6 months, and 12 months post-procedure to monitor valve function, ventricular remodeling, and device stability.

12. Risks, Side Effects, and Complications

Although transcatheter edge-to-edge repair is safer than open cardiac surgery in high-risk populations, it carries inherent procedural, structural, and vascular risks. Risk severity varies based on baseline medical fragility and underlying cardiac anatomy.

Risk Severity Matrix

Frequency / Severity	Complication Name	Clinical Incidence Rate	Description and Management
Common / Mild	Femoral Groin Hematoma	3% – 6%	Localized bruising or fluid collection at access site; managed conservatively with compression and rest.
Common / Mild	Transient Atrial Fibrillation	2% – 5%	Post-procedural atrial arrhythmia; managed with rate/rhythm control agents.
Uncommon / Moderate	Single Leaflet Device Attachment (SLDA)	1% – 3%	Clip detaches from one leaflet; requires evaluation for secondary clip placement or conservative monitoring.
Uncommon / Moderate	Vascular Access Pseudoaneurysm	1% – 2%	Arterial or venous wall defect; treated with ultrasound-guided compression or thrombin injection.
Uncommon / Moderate	Mitral Gradient Elevation	1% – 3%	Excessive narrowing of valve area causing mild-to-moderate stenosis; managed with medical therapy.
Rare / Severe	Cardiac Tamponade / Perforation	< 1%	Accidental puncture of left atrial wall during transseptal crossing; requires emergency pericardiocentesis.
Rare / Severe	Ischemic Stroke	< 1%	Embolization of air or thrombus into cerebral vascular bed; mitigated by rigorous intraoperative heparinization.
Rare / Severe	Device Embolization	< 0.5%	Complete detachment of clip; requires emergent transcatheter retrieval or surgical intervention.

Warning Signs Requiring Urgent Medical Attention

Patients must seek immediate emergency medical care if they experience: sudden severe shortness of breath, rapid swelling or pain at the leg access site, coughing up blood, chest pain, fever, or signs of stroke (face drooping, arm weakness, speech difficulty).

13. Lifestyle and Behavioural Considerations

Long-term lifestyle modifications complement the mechanical benefit of the clip repair by reducing overall heart failure strain and optimizing physical endurance. Patients must align behavioral habits with structured heart failure guidelines.

Evidence-Based Guidance

• Sodium and Fluid Control: Patients with heart failure should adhere to a low-sodium diet (typically <2,000 mg/day) and monitor daily weights to prevent fluid overload.
• Physical Activity: Aerobic exercise should be resumed gradually under medical supervision. Structured cardiac rehabilitation significantly improves aerobic functional capacity post-procedure.
• Infective Endocarditis Prophylaxis: American Heart Association guidelines recommend antibiotic prophylaxis prior to high-risk dental procedures for 6 months post-implantation, or indefinitely if residual regurgitation remains adjacent to prosthetic material.

14. How Outcomes Are Measured

Procedural success and long-term effectiveness are measured by reductions in mitral regurgitation grade, improvements in functional class, and reductions in heart failure hospitalizations. Standardized international registries track these parameters systematically.

Key Clinical Endpoints

Outcomes are defined using criteria established by the Mitral Valve Academic Research Consortium (MVARC):

• Technical Success: Successful deployment of the clip with removal of the delivery system and reduction of MR to Grade 2+ or lower, without intra-procedural mortality or emergency surgery.
• Hemodynamic Success: Achievement of residual MR ≤ Grade 2+ with a mean transvalvular pressure gradient < 5 mmHg as measured on echocardiography.
• Clinical Efficacy: According to registry data (STS/ACC TVT Registry, Mack et al., 2021), over 85% of patients achieve MR ≤ Grade 2+ at 30 days, leading to sustained improvements in New York Heart Association (NYHA) functional class (transitioning from Class III/IV to Class I/II) and significantly reduced 1-year rehospitalization rates for heart failure.

15. Recent Advances and Current Standard of Care

Over the past decade, transcatheter edge-to-edge repair has transformed from an investigational procedure into a primary standard-of-care option for selected patients with mitral regurgitation. Technological innovations continue to expand the range of treatable cardiac anatomies.

Evolution of Clinical Standards

The landmark EVEREST II trial (Feldman et al., 2011) established initial safety and efficacy in primary MR compared to open surgery. Subsequently, the landmark COAPT trial (Stone et al., 2018) demonstrated that adding TEER to guideline-directed medical therapy in patients with secondary MR reduced 2-year heart failure hospitalizations by 47% and reduced all-cause mortality by 38% compared to medical therapy alone.

Recent device advancements—including fourth-generation systems featuring longer clip arms and independent leaflet grasping mechanisms—allow operators to treat complex valve shapes, wide coaptation gaps, and asymmetric regurgitant jets that were previously considered untreatable percutaneously. Current multi-center trials are investigating expanded indications, including use in lower-risk patients and combination therapies for complex structural heart disease.

16. Common Myths and Misconceptions

Myth: Transcatheter edge-to-edge repair completely replaces the need for open-heart surgery in all patients.
Reality: Surgical repair remains the gold standard treatment for young, low-risk patients with primary degenerative mitral regurgitation due to its long-term durability (ACC/AHA Guidelines, 2020). Transcatheter repair is reserved for patients meeting specific risk or anatomical criteria.

Myth: The clip open and closes like a mechanical valve.
Reality: The clip is a stationary implant that holds the middle portions of the valve leaflets together. The remaining unclipped openings on either side continue to open and close naturally during the cardiac cycle.

Myth: Once the clip is placed, heart failure medications can be stopped.
Reality: Patients with secondary mitral regurgitation must remain on optimized guideline-directed medical therapy indefinitely to manage underlying left ventricular dysfunction.

Myth: The procedure involves opening the chest bone.
Reality: Transcatheter repair is performed entirely percutaneously through a small puncture in the femoral vein at the top of the leg.

Myth: A person can only receive one clip during the procedure.
Reality: Operators frequently place two or more clips side-by-side during the same procedure if required to reduce the regurgitant jet to an acceptable level.

Myth: Recovery takes several months in the hospital.
Reality: Most patients are ambulating the day after the procedure and are discharged home within 1 to 3 days.

17. Frequently Asked Questions

What is the primary goal of transcatheter edge-to-edge repair?

The main objective is to reduce severe mitral regurgitation to an acceptable level (Grade 2+ or less). Reducing this leakage lowers blood pressure in the lungs, relieves severe shortness of breath and fatigue, improves physical stamina, and reduces the likelihood of future heart failure hospitalizations.

Is general anesthesia required for this procedure?

Yes, general anesthesia is necessary. Precise real-time transesophageal echocardiography (TEE) imaging requires an ultrasound probe placed in the esophagus throughout the procedure, which is safest and most comfortable under general anesthesia with airway protection.

How long does the clip stay in the heart?

The clip is designed to remain in the heart permanently. Over weeks and months following implantation, bodily tissue grows over the implant (endothelialization), permanently securing it to the valve leaflets without requiring replacement under normal conditions.

Can a patient undergo an MRI after receiving a clip?

Yes. Current transcatheter clips are manufactured from non-ferromagnetic materials (typically cobalt-chromium and nitinol) and are certified as MR-conditional. Patients can safely undergo magnetic resonance imaging under standard operational parameters, usually up to 1.5T or 3.0T field strengths.

What is the difference between primary and secondary mitral regurgitation?

Primary mitral regurgitation stems from a physical structural defect in the valve leaflets or supporting chords themselves. Secondary mitral regurgitation occurs when an enlarged or damaged left ventricle pulls structurally normal valve leaflets apart, preventing them from closing completely.

How long will I stay in the hospital after the procedure?

The average hospital stay is 1 to 2 days. Patients spend the first night in a monitored step-down or cardiac unit and are evaluated for safe ambulation, groin healing, and stable cardiac output before being discharged home.

What happens if the clip does not work or detaches?

If partial detachment (single leaflet device attachment) occurs, echocardiography assesses whether placing a second clip can stabilize the repair. If percutaneous repair is unsuccessful and severe symptoms persist, the Heart Team re-evaluates options, including conservative medical management or open surgery.

Can I travel by airplane after the procedure?

Most patients can safely resume air travel 2 to 4 weeks after the procedure, provided the groin puncture site has fully healed, heart failure symptoms are stable, and the treating cardiologist clears the plan during initial post-discharge evaluation.

Will I feel the clip inside my chest?

No, patients cannot feel the device. The mitral valve lacks pain receptors sensitive to mechanical hardware, and the clip weighs less than a fraction of a gram, operating seamlessly with heart motion.

How soon can I return to work or routine physical activities?

Most patients resume light daily household tasks within 3 to 5 days and return to sedentary office work within 1 to 2 weeks. Heavy physical labor, strenuous athletic training, and heavy lifting (>10 lbs) should be avoided for at least 2 to 4 weeks.

Will I need blood thinners after getting a clip?

Most patients without pre-existing conditions take antiplatelet medications (such as aspirin and clopidogrel) for 1 to 6 months post-procedure to prevent small clots from forming on the new implant while tissue covers it. Patients with atrial fibrillation continue their prescribed oral anticoagulants.

What is a transseptal puncture and is it dangerous?

A transseptal puncture is a routine technique where a specialized needle creates a tiny access hole through the tissue wall (septum) separating the right and left upper chambers of the heart. Performed under direct 3D echocardiographic visualization, it allows safe catheter entry into the left atrium and typically heals naturally over time.

How is success defined right after the procedure is finished?

Immediate procedural success is defined as reducing mitral regurgitation from severe (Grade 3+ or 4+) down to mild or moderate (Grade 1+ or 2+) without causing significant narrowing (stenosis) of the valve or serious complications prior to hospital discharge.

Can a second procedure be performed if leakage returns years later?

Yes, if the valve anatomy remains suitable and adequate valve area exists without stenosis, a second procedure to place an additional clip can be performed years later if regurgitation recurs.