Going Solo: Can TAVI Be Performed Without a Surgical Safety Net?

The heart team at University Hospitals, Cleveland, OH, was in the midst of implanting a transcatheter aortic valve in an elderly patient when things went abruptly wrong.

“The pacemaker happened to poke a hole in the right ventricle,” Marc Pelletier, MD, MS, told TCTMD. “They put in a drain, and they drained it, but it just kept on bleeding. There was nothing they could do. [The patient] went for surgery, and we were able to fix it.”

The story ends well, he continued, thanks to the on-site surgical team that was able to take over. The patient “walked out of the hospital alive and well.”

In the two decades since the first bioprosthetic aortic valve was implanted percutaneously in an inoperable patient, TAVI has revolutionized the care of people with symptomatic severe aortic stenosis. As the procedures have become safer and more standardized, some physicians are starting to question the need for on-site surgical backup, something specified in clinical guidelines and expert consensus statements. Doing so, they argue, would radically improve access to a streamlined procedure that, in the most high-risk patients, represents their only chance at a new valve.

In Pelletier’s case, however, on-site surgical backup was the difference between life and death. “[The patient] would have died if they were in a center doing TAVR without cardiac surgery,” he said.

Improving Patient Access to TAVI

Between 2011 and 2019, more than 275,000 patients underwent TAVI at 715 sites in the US, with volumes increasing year over year, according to data from the Society of Thoracic Surgeons/American College of Cardiology (STS/ACC) TVT Registry. Programs now exist in all 50 states, and TAVI officially surpassed cardiac surgery as the dominant type of aortic valve replacement in 2019.

But physicians continue to worry about access, particularly for patients in rural areas and in underserved neighborhoods of larger North American cities, especially since longer wait times for the procedure are associated with worse outcomes, including a higher rate of mortality, hospitalizations for heart failure, and need for urgent procedures.

Similar problems are seen in the United Kingdom, where the demand for TAVI also “far outstrips capacity,” according to one recent study pointing to median wait times of 20 weeks, but close to 35 weeks in underserved areas. Concerns about access and delay times led to the introduction of the European Society of Cardiology’s “Valve for Life” program, an initiative that also launched in Poland, France, and Portugal, to increase patient access. 

In 5 years, it will not be possible to restrict it only to units that have a really big cardiology or cardiac surgery department. Holger Eggebrecht

Creation of TAVI programs at centers that don’t already offer valve surgery is one possible solution, albeit one not currently permitted by payers or endorsed by guidelines.

Holger Eggebrecht, MD (Cardiovascular Center Bethanien, Frankfurt, Germany), however, believes that needs to change. Conversion to open heart surgery is exceedingly rare with TAVI, he said, noting that data from Germany suggest it’s less than half a percent. Moreover, the collaboration between surgeons, interventionalists, and general cardiologists doesn’t have to be compromised with such a shift.

Add to that the aging population and increasing demand for TAVI, and it becomes clear that the current way of doing things is untenable, he said. 

“I think that the pressure in the US will come because of the workload and the very high [TAVI] numbers that they’re doing over there,” he told TCTMD. “In 5 years, it will not be possible to restrict it only to units that have a really big cardiology or cardiac surgery department.” 

The Case For, and Against, Stand-alone TAVI

Complications that require surgical bailout include device migration, cardiac perforation, and annular/root rupture, as well as other causes like type A dissection and coronary occlusion. Pelletier, a cardiac surgeon who works at a high-volume center where they do more than 400 TAVIs annually, said his group sees such complications every year.  

He believes that the push to consider scenarios where TAVI might be performed without surgical backup comes from a good place, which is the desire to increase patient access. Similar arguments were made when operators first started advocating for PCI and stenting to happen at sites without surgeons on hand to perform rescue CABG. But in Pelletier’s opinion, it’s misguided. Trying to find new ways to treat more people must be balanced with the risks of TAVI, particularly the ability to “salvage” a patient in the rare instances when a procedure goes south.

“I can definitely see the drive, especially in some countries that have socialized medicine, like the UK or Canada, to try to find a way to increase the number of procedures and drive the wait list down,” said Pelletier. “I think that's fine. What I do find a little bit troubling, though, is the willingness to consider doing that at the potential higher risk for patients.”

Speaking with TCTMD, cardiac surgeon Gorav Ailawadi, MD (University of Michigan, Ann Arbor), said that “the likelihood of something going bad is pretty low . . . but it’s still not as safe as putting in a stent. Stents are done in the inpatient and outpatient setting, but it took many years. I know, [people] argue that it’s been two decades [with TAVR], but it really hasn’t been prime time for two decades. I’d say over the last 5 years it’s become that way [but] I don’t think it’s as safe as PCI.” 

Ailawadi, who also works in a high-volume center that performs more than 300 procedures each year, said that most complications with PCI can be handled percutaneously, but that’s not the case with TAVI where the catheters, and complications, are bigger. “Every year, [we get] one or two, at least,” he said. “It’s still less than 1%, but those patients would not have survived [without surgery].”

Moreover, Ailawadi doesn’t believe cardiac surgery is the limiting factor when it comes to patient access in the US. “Hospitals are busy and full and [TAVI] still takes many steps to ensure that there is a low risk of complications,” he said. He pointed out, however, that most patients referred to their center are treated within “a couple of weeks.”

In 2019, a study led by Ashwin Nathan, MD, MS (Hospital of the University of Pennsylvania, Philadelphia), found that of the nearly 600 TAVI programs started in the US between 2012 and 2018, 98% were started in metropolitan areas and more than 50% were started in cities with existing programs. The study also found large disparities in access, “with hospitals serving wealthier patients more likely to start programs.”

Even in areas where there's an abundance of cardiac surgery, there's still limitations in access to this procedure. Ashwin Nathan

Eliminating cardiac surgery isn’t going to help address those challenges, particularly among historically underrepresented groups, Nathan told TCTMD. “In major metropolitan areas that have multiple centers that offer cardiac surgery and TAVR, we still have huge inequities in access to these procedures for Black, Hispanic, and socioeconomically disadvantaged patients,” he said. “Even in areas where there's an abundance of cardiac surgery, there's still limitations in access to this procedure.”

In a different study, Nathan’s team also looked into the hospital-level economics of TAVI, but said it remains uncertain what would happen to the overall cost of the procedure if the need for on-site surgery were eliminated. The reduction in cost with no longer having to maintain an operating room, or pay for surgeons to perform the procedure, could be offset in other ways—with increases in complications that lead to longer hospital stays, for example.

Similar Complications at Sites Without Surgery

Current US and European guidelines state that TAVI should only be performed at heart valve centers with on-site cardiac surgery (class I recommendation), but there are some, like Eggebrecht, who believe it can be done safely without surgical backup. In a viewpoint published last month in JACC: Cardiovascular Interventions, Miriam Compagnone, MD (Morgagni Pierantoni Hospital, Forli, Italy), and colleagues make such a case.

“Performing TAVR in centers without on-site cardiac surgery could significantly increase the number of procedures worldwide, resulting in quicker TAVR access and, subsequently, a lower risk of adverse events during wait time for patients with severe aortic stenosis,” they write.

In fact, it’s already been done in some countries, including Germany, Austria, and Spain. In 2014, the German Cardiac Society relaxed recommendations to allow hospitals without on-site cardiac surgery to operate TAVI programs if they have an existing contract with an external surgical department and an interdisciplinary heart team in place.

Eggebrecht, who has analyzed outcomes of procedures done at sites with and without on-site cardiac surgery, said the desire to perform TAVI without backup isn’t simply because cardiologists want to take over from their surgical colleagues. He emphasized that even though patients may be treated at centers without on-site surgery, the heart team can continue to play a pivotal role. Smaller centers without on-site surgery can not only increase access but also provide more high-quality, personal care than the large academic medical centers.

“If you go there, it's a huge hospital clinic,” he said. “You get lost a little bit and you don't have any personal relationship to the doctor who does the procedure. You don't know them, and you don't have faith. You maybe just feel like a number, one of the thousand procedures that they are claiming to do every year.”

The German decision has since been rescinded, though, forcing the few centers that did TAVI without cardiac surgery to find a solution. For Eggebrecht, that now involves treating patients at a surgery-capable hospital 90 miles from home 2 or 3 days per month, a trip his patients also have to make.

In 2016, as reported by TCTMD, he published data from the German Quality Assurance Registry (AQUA) showing similar rates of in-hospital mortality and major complications with TAVI in centers with and without surgical backup. In 2022, there were nearly 24,000 TAVIs performed in Germany, with just 0.34% of these procedures requiring an intraoperative conversion to sternotomy, he said. Comparatively, there were roughly 715,000 PCIs done that year and 0.12% of these required conversion to open heart surgery, said Eggebrecht.

Other data also suggest comparable TAVI outcomes in sites without surgical backup. For example, a study conducted at 10 centers without on-site cardiac surgery in Spain between 2010 and 2018 found similar outcomes when compared with procedures done traditionally. Of the 384 cases done at centers without surgery, there was a conversion to sternotomy in one patient following a ventricular perforation and cardiac tamponade. The patient survived.

In their article, Compagnone and colleagues say that if TAVI without surgery goes forward, sites would be required to adhere to various criteria and meet certain quality metrics and safety assessments. If the operators are experienced (at least 100 transfemoral TAVIs, with 50 as the primary operator) and maintain high annual volumes with excellent outcomes, and if they have a cardiac intensive care unit and on-site vascular surgery consults for managing vascular complications, then it may be possible to perform TAVI without on-site cardiac surgery, they write.

Also critical to the success of such a program are regular heart team meetings for multidisciplinary patient selection and procedural planning, including the ability to refer patients to a hospital with on-site surgery.

To do 50 TAVRs a year, with no surgery on-site, it’s like walking on water without a safety net. Philippe Généreux

Data from the STS/ACC TVT registry also show that the use of cardiopulmonary bypass is declining significantly, down from 4.1% in 2011 to 0.4% in 2019. Additionally, the conversion to open heart surgery is down from 1.4% to 0.4%, with conversion rates similar in patients deemed high/extreme, intermediate, and low risk for surgery.

Compagnone and colleagues believe it’s possible to identify those unlikely to need conversion to surgery, such as those at prohibitive surgical risk where surgery would be futile and those without anatomical features related to a higher risk of complications, such as low coronary height and left ventricular outflow tract calcification. Eggebrecht agreed that such planning is helpful.

“From my experience, I would assume [complications are] only happening in very challenging anatomies where you’re really pushing the limits,” said Eggebrecht. For example, avoiding a balloon-expandable valve in highly calcified annuli could limit the risk of rupture. “The same applies to maneuvering wires and perforation of the ventricle. I haven’t had one single perforation in my whole life, knock on wood. If it occurs, you would [perform] a pericardial puncture because the patient is most threatened by tamponade. Then, of course, you need to get the patient to surgery.”

Even in centers with surgery on-site, clinical outcomes are extremely bleak in those converted to surgery, said Eggebrecht. For example, in-hospital mortality was 46.0% in TAVI patients with complications needing open heart surgery, and as high as 62% for cases of annular rupture, according to an analysis of the European Registry on Emergent Cardiac Surgery During TAVI (EuRECS-TAVI).

It Can Be Done, But Should It?

Philippe Généreux, MD (Morristown Medical Center, NJ), an interventional cardiologist, isn’t convinced that green-lighting TAVI centers without on-site surgery is the best path forward.

“With TAVR, there's still a lot of complexity in the assessment and some unpredictability at times in the procedure,” he told TCTMD. “There’s also the assessment of the patient, especially in lower-risk [settings], that really needs the input of a surgeon, the input of a cardiologist. I believe that to open the door to no [cardiothoracic] surgery on-site may lead to a suboptimal outcome in the future.”

He worries that eliminating surgical backup would inevitably lead to patients being treated at low-volume centers. “To do 50 TAVRs a year, with no surgery on-site, it’s like walking on water without a safety net.”  

Nathan also disagrees with the no-surgery concept. Moreover, he doesn’t think comparisons with PCI are fair.

“PCI became overall a lot safer over the last several decades, to the point where the complications that occur often do not need cardiac surgery,” he told TCTMD. “They can be managed in the cath lab. . . . For TAVR, overall, it’s a very safe, very effective procedure, but I think having a cardiac surgeon available to handle some of those pretty significant complications is something that I think is still necessary.”

Right now, the Centers for Medicare & Medicaid Services (CMS) requires several conditions to be met for reimbursement. The patient must be under the care of a heart team, with both the cardiac surgeon and interventional cardiologist examining the patient “face-to-face” to assess their eligibility for surgery or TAVI. Importantly, CMS mandates that TAVI must take place in a hospital that includes both on-site heart valve surgery and interventional cardiology programs and the interventionalist and surgeon must participate in the intraoperative aspects of the procedure.

For proponents of continued on-site cardiac surgery, they emphasize that it’s not always possible to identify who will or won’t develop complications. “We’ve done approximately 5,000 TAVRs at Morristown through the years, and every year there’s a case that surprises you, that you never would have predicted,” said Généreux. The patients have “an acute complication and we actually save them because the surgeon was readily available.”

“We started a program when I was in Canada in 2011,” added Pelletier. “The thing we quickly realized was that there's a level of unpredictability to TAVR that is much more present than it is with open cardiac surgery where you're seeing everything. Don't get me wrong, complications can happen with open surgery as well that you don't expect, but there's a really unpredictable nature to TAVR that we don't see with open surgery.”

Shifting TAVI to centers without surgical backup will inevitably lead to an increase in patient deaths, he predicted. This doesn’t make sense, particularly in Western countries, where hospitals are intensely focused on results and where those results are tied into internal audits, reimbursement, physician/hospital ratings, and more.

Moreover, Pelletier said that even if mortality rates in patients requiring bailout surgery are high, death is not an absolute certainty.

Don't get me wrong, complications can happen with open surgery as well that you don't expect, but there's a really unpredictable nature to TAVR that we don't see with open surgery. Marc Pelletier

“If you flip those numbers around, that means that 40% to 60% of those patients are surviving,” he said. “I understand the problem, and I understand that we need to provide access in a [timelier] manner, but saying, well, let's just provide a little bit less support, a little bit less care—it's going to be okay 98% or 99% of the time. That’s true, but I don't think that's what we should be striving for in medicine.”

Ailawadi noted out that even when unpredictable complications occur, they are just as deadly for low-risk patients.

“What we have found, unfortunately, is that even when low-risk patients need some type of emergent rescue, there’s still a high mortality,” he said. “You could certainly argue that there are some [inoperable] patients that could be done at a place without surgery because there is not going to be any cardiac surgery, but for any person that is a salvage candidate, at least if it was my family member, I would want them to be in a place where there is backup.”

In an editorial last month in JACC: Cardiovascular Interventions, Marina Urena, MD, PhD (Bichat Claude Bernard Hospital/Assistance Publique Hôpitaux de Paris, Paris, France), and colleagues say there might be value in bringing TAVI to select sites without surgery, especially in remote areas, but the concept needs to be tested in a randomized, controlled trial. 

Inadvertent Effects on Heart Team

Aortic valve replacement has been heralded for ushering in the era of the collaborative heart team, with cardiologists, interventionalists, surgeons, and imagers all working together to provide the best decisions and treatment for patients with symptomatic severe aortic stenosis.

“For TAVI, the one thing that has made this such a successful procedure, I think, above all, has been the formation of heart teams,” said Pelletier, noting that the team-based model has been extended to the treatment of other diseases. “It puts people into the room that sometimes were at odds or were not working collaboratively together. It puts them in the room together, forces them to really look at all aspects of this patient's results and tests, and as a team, they make a really good decision.”

Instead of eliminating on-site surgery, Généreux believes there are other ways to streamline TAVI. For him, the CMS requirement that both the surgeon and interventional cardiologist be in the lab is inefficient and obsolete. Eggebrecht agrees, noting that it can be frustrating for highly trained surgeons to stand at the table, simply holding a wire, or adding a stitch to close an enlarged puncture site.

But even here, reaching consensus isn’t easy.

“That relationship is critical, not only for preprocedural assessment, but for intraprocedural management as well,” Nathan said. “The majority of TAVRs in this country are done through percutaneous transfemoral approaches, but there are alternative access requirements for a significant proportion of patients. Often these alternative access modalities need the presence of surgery. Surgeons are very, very good at endovascular procedures themselves as well.”