Heart Valve Repair and Replacement Surgery

Heart valve repair and replacement surgery encompasses a range of open surgical and catheter-based procedures designed to restore normal valve function in patients whose valves have become stenotic, regurgitant, or structurally compromised. The cardiac valves — aortic, mitral, tricuspid, and pulmonary — regulate unidirectional blood flow through the heart's chambers, and failure in any of them can produce progressive heart failure, arrhythmia, or sudden death. This page covers the anatomical targets, procedural mechanisms, clinical indications, and the frameworks surgeons and cardiologists use to decide between repair and replacement. For regulatory context governing cardiac surgical programs and device approvals, the regulatory context for cardiology section provides relevant agency and statute references.

Definition and Scope

Heart valve surgery refers to any operative intervention — open-chest or transcatheter — intended to correct valvular dysfunction severe enough to cause symptoms or measurable cardiac injury. The four valves divide into two functional categories: the atrioventricular valves (mitral and tricuspid, separating atria from ventricles) and the semilunar valves (aortic and pulmonary, separating ventricles from the great arteries).

The principal pathological states addressed by surgery are:

• Stenosis — restricted leaflet opening that obstructs outflow, quantified by valve area and mean pressure gradient on echocardiography (American College of Cardiology/American Heart Association Valve Guidelines, 2021)
• Regurgitation — incomplete leaflet coaptation allowing retrograde flow, graded on a scale of 1 (trivial) to 4 (severe)
• Mixed lesions — simultaneous stenosis and regurgitation, common in rheumatic disease
• Structural failure — infective endocarditis, leaflet perforation, chordal rupture, or prosthetic valve dysfunction

The U.S. Food and Drug Administration (FDA) classifies prosthetic heart valves as Class III devices under 21 CFR Part 870, requiring premarket approval (PMA) before commercial distribution (FDA, 21 CFR Part 870). Surgical programs performing valve procedures at U.S. hospitals operate under the Society of Thoracic Surgeons (STS) National Database reporting standards, which track 30-day mortality, stroke, and reoperation rates as primary quality endpoints.

How It Works

Repair Techniques

Valve repair preserves native tissue and carries a lower long-term risk of thromboembolism and prosthetic valve endocarditis compared to replacement. Mitral valve repair is the preferred approach when anatomically feasible, with repair rates exceeding 95% at high-volume centers according to STS database analyses.

Core repair techniques include:

1. Annuloplasty — implantation of a rigid or flexible ring to remodel the annulus, restoring leaflet coaptation geometry; used in mitral and tricuspid regurgitation
2. Leaflet resection or plication — removal or folding of prolapsed or flail leaflet segments, most commonly the posterior mitral leaflet
3. Chordal replacement — synthetic polytetrafluoroethylene (PTFE) neochordae reattach detached or elongated chordae tendineae to the papillary muscle
4. Commissurotomy — surgical separation of fused leaflet edges in mitral stenosis, predominantly of rheumatic origin
5. Decalcification — débridement of calcium deposits from aortic or mitral leaflets to improve mobility

Replacement Techniques

When repair is not anatomically viable, surgeons excise the native valve and seat a prosthesis. Cardiopulmonary bypass supports circulation throughout. Two prosthesis classes dominate:

• Mechanical valves — carbon-leaflet bileaflet designs (e.g., St. Jude Medical, CarboMedics) with projected durability exceeding 20–25 years but requiring lifelong anticoagulation with warfarin (target INR 2.0–3.5 depending on position and patient risk per ACC/AHA guidelines)
• Bioprosthetic valves — porcine or bovine pericardial tissue mounted on a stent or stentless, typically lasting 10–15 years in older patients without anticoagulation after the initial 3-month perioperative window

Transcatheter approaches — most notably transcatheter aortic valve replacement (TAVR), described in detail separately — deploy a bioprosthetic valve via catheter without open sternotomy, using femoral, subclavian, or transapical access.

Common Scenarios

The clinical situations most frequently driving referral for valve surgery include:

• Severe aortic stenosis — valve area less than 1.0 cm² with mean gradient above 40 mmHg; the most common acquired valve lesion requiring surgery in adults over 65
• Severe mitral regurgitation — left ventricular ejection fraction decline below 60% or end-systolic diameter above 40 mm triggers intervention thresholds per ACC/AHA 2021 guidelines
• Aortic regurgitation with ventricular enlargement — end-diastolic diameter exceeding 65 mm or symptomatic status
• Infective endocarditis — heart failure unresponsive to antibiotics, persistent bacteremia, large vegetations above 10 mm with embolic events, or periannular abscess
• Rheumatic mitral stenosis — mitral valve area below 1.5 cm² with symptoms; commissurotomy or replacement depending on leaflet morphology score

Patients with heart valve disease as an underlying diagnosis represent the primary surgical population, but overlap exists with patients carrying congenital anomalies or those who have undergone prior coronary artery bypass surgery in whom valve pathology was incidentally identified.

Decision Boundaries

The choice between repair, surgical replacement, and transcatheter replacement depends on four intersecting factors: valve anatomy, patient operative risk, institutional expertise, and patient preference. A structured Heart Team — cardiologist, cardiac surgeon, and imaging specialist — is mandated by Centers for Medicare & Medicaid Services (CMS) coverage determinations for TAVR and recommended by ACC/AHA guidelines for all complex valve decisions.

The STS Predicted Risk of Mortality (PROM) score stratifies operative risk:

• Low risk: STS PROM below 4%
• Intermediate risk: STS PROM 4%–8%
• High risk or inoperable: STS PROM above 8% or anatomical/physiological contraindications to sternotomy

Repair is preferred over replacement when durable repair is achievable because it avoids prosthesis-related complications and preserves subvalvular architecture. The cardiology authority index provides cross-references to related procedural topics.

Bioprosthetic valves are generally selected for patients above age 65 in the aortic position and above age 70 in the mitral position, where structural valve deterioration during the patient's expected lifespan is less likely than in younger recipients. Mechanical valves remain the default for patients under age 50 who have no contraindication to anticoagulation. Ages 50–65 represent a shared-decision zone where bleeding risk, lifestyle factors, and patient preference each carry substantial weight per the ACC/AHA framework.

Pulmonary valve replacement — the least common of the four — arises most frequently in adults with repaired tetralogy of Fallot or other congenital heart defects who develop free pulmonary regurgitation after prior right ventricular outflow tract reconstruction.

References

• ACC/AHA Guideline for the Management of Patients With Valvular Heart Disease (2021) — American College of Cardiology / American Heart Association
• FDA 21 CFR Part 870 — Cardiovascular Devices — U.S. Food and Drug Administration
• Society of Thoracic Surgeons National Database — STS
• Centers for Medicare & Medicaid Services: TAVR Coverage Determination — CMS
• American Heart Association: Heart Valve Disease — AHA

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