Edwards Mitral Valve Options: Surgical and Transcatheter

Edwards Lifesciences has shaped mitral valve therapy more than any other single company, beginning with the first successful prosthetic mitral valve implant in 1960 and extending through a modern portfolio that spans surgical bioprostheses, transcatheter repair devices, and a new purpose-built transcatheter replacement system. The name “Edwards mitral valve” can refer to several distinct products depending on the context: a surgeon might mean the Carpentier-Edwards Perimount pericardial bioprosthesis, an interventional cardiologist might mean the PASCAL transcatheter repair system or the SAPIEN M3 replacement valve, and a historian of cardiac surgery would think of the original Starr-Edwards ball-and-cage prosthesis that launched the entire field. Understanding these devices as a connected family, rather than isolated products, gives a clearer picture of where mitral valve treatment stands today and where it is heading.

Where It All Started

Before Lowell Edwards, a retired engineer, partnered with Albert Starr, a young cardiac surgeon at the University of Oregon, no patient had survived longer than three months with a prosthetic valve in the mitral position.¹ Working together, they developed and implanted the first Starr-Edwards caged-ball valve in less than two years. That device, crude by today’s standards, proved that replacing a diseased mitral valve was survivable and could restore patients to functional lives. The Starr-Edwards valve became the benchmark against which every subsequent prosthesis was measured, and its legacy is the reason the company that grew from Edwards’s engineering workshop still bears his name.

The Carpentier-Edwards Perimount Bioprosthesis

For decades, the workhorse surgical mitral valve from Edwards has been the Carpentier-Edwards Perimount, a bioprosthesis made from bovine pericardium (the tough sac around a cow’s heart) mounted on a flexible stent frame. Multiple long-term studies have confirmed its durability, particularly in older patients. A 15-year follow-up study concluded that the Perimount was a reliable tissue valve choice in the mitral position, especially for patients over 60.² A separate 25-year study of 450 implants reinforced that conclusion, reporting a low rate of valve-related events over two decades.³

Durability is the central concern with any bioprosthetic valve, because biological tissue wears out in ways that mechanical valves do not. An independent study following the Perimount in the mitral position for 25 years found that freedom from reoperation due to structural valve deterioration at 20 years was roughly 24% for patients with degenerative disease and about 15% for those with non-degenerative disease.⁴ Age mattered substantially: patients under 60 had a much higher rate of structural deterioration over 18 years than those 60 and older. This is why surgeons have traditionally steered younger patients toward mechanical valves or mitral repair whenever possible, reserving bioprostheses primarily for older individuals who are less likely to outlive the valve.

RESILIA Tissue and the Fight Against Calcification

The main reason bioprosthetic valves eventually fail is calcification, a gradual buildup of calcium deposits in the tissue that stiffens the leaflets and degrades valve function. Edwards developed a proprietary tissue treatment called RESILIA, designed to address one of the chemical drivers of that process: residual aldehyde left behind after the glutaraldehyde fixation that all bioprosthetic tissue undergoes during manufacturing. In laboratory testing, RESILIA tissue had dramatically lower residual aldehyde content compared to conventionally fixed tissue, and in an animal implant model, it accumulated far less calcium over 60 days. RESILIA tissue showed a median calcium content of about 10 micrograms per milligram, compared to roughly 227 for standard glutaraldehyde-fixed tissue.⁵

The first mitral bioprosthesis to incorporate this tissue is the MITRIS RESILIA valve. Early clinical data have been encouraging: a study reported stable mean pressure gradients of around 4 mmHg through two years, with no cases of structural valve deterioration and a two-year freedom from all-cause mortality of about 93%.⁶ Longer follow-up data from a study tracking both first-time and redo patients receiving the MITRIS RESILIA valve showed that at three years, freedom from structural valve deterioration was 100%, and freedom from all-cause mortality was 89%.⁷ Whether these early results will translate into meaningfully longer valve life spans compared to the Perimount remains to be seen, but the animal data on calcium reduction give reason for cautious optimism.

Transcatheter Edge-to-Edge Repair With the PASCAL System

Not every mitral valve needs to be replaced. For many patients with mitral regurgitation, where the valve leaks backward rather than failing to open, repair is the preferred approach. Edwards entered the transcatheter repair space with the PASCAL system, a catheter-delivered device that clips the leaking mitral leaflets together to reduce regurgitation without open-heart surgery. The device consists of broad paddles that distribute force across the leaflet surface and a central spacer that gives the leaflets something to close against, reducing the gap that allows blood to leak.⁸ A smaller variant, the PASCAL Ace, has narrower paddles with increased curvature, allowing it to work in tighter anatomies.

The CLASP IID randomized trial compared PASCAL head-to-head against Abbott’s MitraClip, the established market leader, in patients with degenerative mitral regurgitation. At one year, PASCAL met its noninferiority endpoints for safety and effectiveness, with rates of mitral regurgitation reduced to mild or less in about 77% of PASCAL patients versus 71% for MitraClip.⁹ At two years, those results held steady: roughly 95% of PASCAL patients had regurgitation reduced to moderate or less, with no statistically significant differences between devices in mortality, heart-failure hospitalization, or need for reintervention.¹⁰ For patients and their physicians, the practical takeaway is that both devices perform similarly, giving heart teams a meaningful choice when planning a repair procedure.

Transcatheter Replacement With the SAPIEN 3 Valve-in-Valve

When a surgically implanted bioprosthetic mitral valve fails, the patient faces a difficult decision: undergo another open-heart surgery, or try a catheter-based approach. Edwards’ SAPIEN 3 balloon-expandable valve, originally designed for aortic valve replacement, has been used off-label to deploy a new valve inside the old failing one, a technique called valve-in-valve. A large registry study of over 1,500 patients who underwent transcatheter mitral valve-in-valve with the SAPIEN 3 reported a technical success rate of about 97%. One-year mortality was roughly 17%, and the proportion of patients with severe heart failure symptoms dropped from 87% before the procedure to under 10% afterward.¹¹ The study also found that a transseptal approach, threading the catheter across the wall between the heart’s upper chambers, produced better survival than the transapical route, which involves a small incision through the tip of the heart.

Five-year data from the MITRAL trial added more nuance. Patients who received a valve-in-valve inside a previously implanted bioprosthesis fared best, with a five-year mortality of about 21%. Those with a valve placed inside a surgical ring or into a heavily calcified native annulus had considerably higher mortality, in the range of 65-68%.¹² These latter scenarios remain technically demanding, often requiring creative modifications to both the valve and the delivery system to achieve adequate results.¹³

The SAPIEN M3 and a Purpose-Built Era

Using a valve designed for the aortic position in the mitral spot was always a workaround. The mitral annulus is larger, more oval, and moves more dynamically than the aortic annulus, which means an aortic valve repurposed for the mitral position can face anchoring challenges and a heightened risk of obstructing the left ventricular outflow tract. Edwards addressed these limitations with the SAPIEN M3, a system designed from the ground up for transcatheter mitral valve replacement. It uses a two-component design: a self-expanding nitinol dock that wraps around the structures beneath the mitral valve to create a stable landing zone, and a balloon-expandable SAPIEN 3 valve that is deployed inside that dock.¹⁴ This anchoring strategy does not depend on calcification to hold the valve in place, which broadens the pool of patients who can be treated.

The pivotal ENCIRCLE trial evaluated the SAPIEN M3 in patients with mitral regurgitation who were poor candidates for surgery or transcatheter repair. The primary composite endpoint of death and heart-failure rehospitalization at one year came in at about 25%, well below the prespecified performance goal of 45%. There were no cases of outflow tract obstruction causing significant problems and no conversions to emergency surgery during the procedure.¹⁵ If these results hold up in broader use, the M3 could fill a major gap for patients who are too sick for surgery but whose anatomy is not suitable for clip-based repair.

The Outflow Tract Obstruction Problem

One of the unique engineering challenges of putting any device in the mitral position is the left ventricular outflow tract, the channel through which blood exits the heart. A bulky prosthesis in the mitral annulus can push the anterior leaflet of the native valve forward and partially block that channel, a complication that can be fatal if severe. This risk can be predicted with cardiac CT imaging before the procedure.¹⁶ When the predicted risk is high, interventional teams have developed strategies to deal with the anterior leaflet proactively. These include alcohol septal ablation, radiofrequency ablation, and electrosurgical laceration of the leaflet before or during the valve implant.¹⁷ The SAPIEN M3’s dock-based design was specifically engineered to reduce this risk, and the ENCIRCLE trial data suggest it succeeded on that front.

Imaging and Preprocedural Planning

Whether the planned procedure is a transcatheter repair, a valve-in-valve replacement, or a native TMVR, detailed imaging of the mitral annulus is essential for choosing the right device size and approach. Cardiac CT provides the high spatial resolution needed to measure the annulus precisely and, critically, to assess the distance between the annulus and the circumflex artery, which runs close enough to be damaged by an anchor or implant placed in the wrong spot.¹⁸ Three-dimensional transesophageal echocardiography provides a complementary picture. One comparison found no systematic difference in annular measurements between 3D echo and CT, supporting the use of echo as a backup or cross-check when CT imaging is ambiguous.¹⁹

Dedicated software tools can now convert CT datasets into simulated echocardiographic views, letting the interventional team rehearse catheter positioning and anchor placement before they enter the procedure room. This kind of fusion planning has become especially valuable for complex cases like valve-in-ring and valve-in-MAC procedures, where small miscalculations in device sizing or positioning can lead to paravalvular leak or outflow obstruction.

Anticoagulation After a Bioprosthetic Mitral Valve

One reason patients choose a bioprosthetic valve over a mechanical one is the expectation of lighter blood-thinning treatment. Mechanical mitral valves require lifelong warfarin, while bioprosthetic valves typically need anticoagulation for only a few months after surgery. But the specifics of that short-term anticoagulation have been debated, particularly whether newer direct oral anticoagulants can safely replace warfarin in the early postoperative period.

A meta-analysis comparing newer oral anticoagulants to warfarin after bioprosthetic mitral valve replacement found no significant difference in rates of stroke, major bleeding, or all-cause mortality, leading the authors to conclude that newer agents appear to be a safe and effective alternative.²⁰ However, a separate and larger meta-analysis specifically focused on valve thrombosis told a more cautious story. Patients on any oral anticoagulant had about a 3.5-fold lower rate of bioprosthetic mitral valve thrombosis compared to those on no anticoagulant at all. And among those on anticoagulants, patients taking warfarin had about a 3.2-fold lower incidence of valve thrombosis compared to those on newer agents.²¹ This disagreement matters: the first meta-analysis found no clear difference in clinical events like stroke, while the second found a real difference in subclinical valve thrombosis. The practical implication is that many cardiologists still prefer a few months of warfarin after a bioprosthetic mitral valve, even though newer agents might be acceptable for patients who have strong reasons to avoid warfarin.

Monitoring for Structural Valve Deterioration

All bioprosthetic valves eventually wear out. Recognizing early signs of deterioration is important because it gives the heart team time to plan a controlled reintervention rather than an emergency one. Structural valve deterioration in the mitral position is formally defined as permanent changes to the valve leaflets, such as thickening, calcification, or tearing, confirmed by imaging alongside measurable worsening of valve function on echocardiography.²² In practical terms, clinicians watch for a rising mean pressure gradient across the valve (with a threshold of 6 mmHg often used as a flag for significant stenosis) or the return of moderate or worse regurgitation.²³

When deterioration is caught early enough, patients with a failing Edwards bioprosthesis in the mitral position now have the option of a transcatheter valve-in-valve procedure rather than a full redo surgery. A cost-effectiveness analysis comparing the two approaches found that valve-in-valve TMVR was both less expensive and associated with slightly better short-term survival, producing an estimated savings of roughly $16,700 per patient and one fewer death per 25 patients treated.²⁴ This calculus has made many clinicians more willing to implant a bioprosthetic valve in the first place, knowing that a less invasive bailout exists down the road.

The Heart Team and How Patients Get Matched to Devices

With so many options now available, from surgical repair and surgical replacement to transcatheter repair and transcatheter replacement, choosing the right procedure for a given patient is no longer a one-physician decision. A multidisciplinary heart team, typically including cardiac surgeons, interventional cardiologists, imaging specialists, and anesthesiologists, evaluates each patient’s anatomy, comorbidities, and preferences.²⁵ Studies of this approach have shown that reserving surgical repair for lower-risk patients with favorable anatomy, while directing high-risk patients toward transcatheter options, produces better-than-expected outcomes across the board.²⁶

In practice, the decision tree branches early. If the valve can be repaired, surgical repair remains the gold standard for patients who can tolerate surgery. If repair is not feasible but the patient is a reasonable surgical candidate, a bioprosthetic or mechanical valve replacement follows. If the patient is too frail for surgery but has anatomy suitable for a clip, a PASCAL or MitraClip procedure enters the conversation. And for patients who are truly left without good options, the SAPIEN M3 now offers a purpose-built transcatheter replacement pathway. The point of the heart team is to avoid defaulting to any single technology and instead match the device to the patient.

Edwards Valves in Pediatric Patients

Mitral valve disease in children presents unique challenges. Children’s hearts are small and still growing, so any prosthesis implanted today will eventually be outgrown or will need replacement. The SAPIEN 3 valve has been used surgically in children whose mitral annulus is large enough to accommodate it, with one published case describing its implantation in a child with prosthetic valve endocarditis after multiple prior surgeries. The procedure was safe and delivered adequate hemodynamics in the short term, highlighting the valve’s potential when a bioprosthesis is needed in a pediatric setting.²⁷

Transcatheter valve-in-valve implantation has also been performed in pediatric patients with failing bioprosthetic mitral valves. A case series reported substantial hemodynamic improvement, with the average gradient across the valve dropping from about 20 mmHg before the procedure to 1 mmHg afterward, and functional status improving dramatically.²⁸ These procedures remain uncommon and are reserved for children at high surgical risk, but they illustrate how the transcatheter toolkit originally built for elderly adults is being adapted across the age spectrum. For pediatric cardiologists, the ability to deploy a new valve inside an old one via catheter means fewer sternotomies over the course of a child’s lifetime, a meaningful reduction in cumulative surgical burden.