Pediatric cardiothoracic surgery centers: How to compare outcomes for kids with congenital heart defects

May 1, 2019

A yearly research report highlights mortality risk data for cardiothoracic surgery centers across 5 categories of surgical outcomes for congenital heart defects (CHD) in children.

Mortality risk for children with congenital heart conditions varies greatly among US cardiothoracic surgery centers, and these programs differ when it comes to patient volume and case complexity.

It’s a complicated and still imperfect process of comparing apples to apples when reporting on US cardiothoracic surgery program data, according to John E. Mayer Jr., MD, who chairs the Society of Thoracic Surgeons (STS) Congenital Heart Surgery Database Task Force.

However, there are some resources that can help pediatricians and patients’ families find the best center for each patient’s needs.

Mortality risk data

The STS publishes an annual report on hospitals’ voluntary reporting of mortality risk associated with congenital heart surgery procedures. The Society’s 2018 Congenital Heart Surgery Database mortality risk model is based on reporting by over 95% of the US centers. Now, nearly 74% of US centers that perform these procedures are publicly reporting, an increase from only 23% publicly reporting the data in January 2015, according to Mayer.

In the latest report, 12 of 119 participating centers received the highest 3-star designation, 85 got 2 stars, and 13 received 1 star, or the lowest rating. Nine had no stars because of incomplete data.

The report offers aggregate data over a 4-year period for each participating hospital, including a list of the surgeons whose cases make up that hospital’s data. Cases are broken down into 5 risk categories, with category 1 including lower mortality risk procedures, such as atrial septal defect repair, to category 5, which includes first-stage palliative procedures for a particular type of single ventricle known as hypoplastic left heart.

Reading between the lines

The STS report is a good place to start for researching centers for CHD patients, but it should not be a pediatrician’s or family’s only reference for a center’s outcomes, according to Mayer. It’s important to clarify the meaning of the star rating system because that’s largely misunderstood, he says.

“What the stars are intended to depict is how an institution is doing relative to its case mix. That’s an important detail because it is an incorrect conclusion that an institution that has a 3-star ranking is better than an institution with a 2-star ranking. That’s where the star system has created potential confusion,” Mayer says.

“If one institution has a higher percentage of the more complicated cases, then even if it does just as well, if not better, than another institution that has a lower percentage, it turns out that the institution that is doing the more complex case mix actually can appear to be performing as well,” Mayer explains. “It’s one of the real limitations in the star system and the STS website makes it clear that the star rating should not be used to compare 2 institutions.”

The STS is making a substantial financial commitment to develop a system that more accurately risk adjusts the mortality rates by institution, according to Mayer. There isn’t yet a reporting system that perfectly risks adjusts for the specialty due to the range and complexity of the operations, particularly when one has to consider hundreds of different types of diagnoses and operations, he says.

“One fundamental problem is we are still defining patient cohorts by the operations that they received. It turns out that you can have 2 different patient populations who receive the same operation and, because of other coexisting factors, they actually behave quite differently,” Mayer says. “For example, there is a defect called an atrioventricular canal [AV canal] defect, which occurs in about 20% of patients with Down syndrome. If you have an AV canal defect repair and Down syndrome, you actually have a lower [mortality] risk than if you don’t. And yet if you go to a different patient population-patients undergoing operations for single ventricle and a patient with Down syndrome-the relative risk is several times higher than the rest of the population with single ventricle having the same operation. You have to have a risk-adjustment system that includes not only the presence or absence of Down syndrome but also in the context of the underlying heart disease. There are many such syndromes and non-heart anomalies that must be considered.”

The stars are, however, an indication of how an institution is performing for its case mix, he says.

Mayer says he and colleagues are also concerned about only using the current STS reporting as a patient/family awareness tool for centers that got only 1 star. Rather, it might signal that a pediatrician considering referring to that center do a little more digging about why the center got this rating. It shouldn’t be a knockout factor, he says.

For example, some institutions’ observed-to-expected mortality rates might fall on the border between star ratings, which can create a perception that there is a difference when one doesn’t actually exist, according to Christopher A. Caldarone, MD, chief of Congenital Heart Surgery at Texas Children’s Hospital, Houston, a 3-star program according to the STS report.

“Another problem is some institutions may be quite superior in their ability to take care of one problem in congenital heart surgery but markedly less so in another type of problem. If that institution happens to be a 3-star program, [it] may look like [it’s] superior when in fact, for that particular problem, a 2-star or even a 1-star program might be superior,” Caldarone says.

The STS report is a good starting place when researching cardiothoracic centers, according to Riley Children’s Health cardiothoracic surgeon Mark W. Turrentine, MD. Riley Hospital for Children at Indiana University Health in Indianapolis, Indiana, is among the 3-star centers in the most recent STS report. “But not all highly respected programs are going to be 3-star,” he says.

Turrentine says that when he looked at the 10 cardiothoracic surgery centers he would consider sending someone to, half were 3-star and half were 2-star.

“I think the 3-star is a place to start because you know that it’s data that has been validated and it’s comparing a program’s outcomes to what their expected outcomes should be,” Turrentine says. “To be 3-star you have to have less than a 1 O/E [observed/expected outcomes] ratio. That allows you to see what centers are performing better than expected. It doesn’t mean that they’re the only programs to think about.”

A comprehensive picture

Pediatricians and families should look at a cardiothoracic heart program’s case volume, according to Mayer.

High-volume programs tend to be exposed to not only many patients but also to more cases on the complex end of the spectrum, according to Turrentine. “I think having a program that has been established and has a stable surgical workforce is also important,” he says. “If people that have performed well are no longer with that institution, that institution might still carry the designation for several more cycles.”

Rankings in the US News and World Report also may help to distinguish the better centers, according to Mayer, although the US News and World Report system has its own limitations.

“Then, I suggest contacting the institution directly and asking what the results are for a given diagnosis,” Mayer says. “My recommendation would be to try to understand what the results are for the diagnosis your patient actually has. Or the pediatrician, if he knows what the diagnosis is, can go to that institution’s website. Almost all the institutions now have a website that provides outcomes by diagnosis.”

Beyond the stars

Contemporary Pediatrics talked with surgeons from 4 of the 3-star centers and asked what they think makes their institutions stand out as quality cardiothoracic surgery centers.

Mark W. Turrentine, MD, Riley Hospital for Children at Indiana University Health: Riley is a long-standing program that has been training residents and fellows for about 60 years, according to Turrentine.

“Up until about 15 years ago, it was the only program in the state, so it has enjoyed a high volume of work, as well as a very balanced exposure to all aspects of congenital heart surgery,” he says. “All the surgeons that have been here have made careers of being here in the Division of Cardiothoracic Surgery. We’ve had no turnover of surgeons. Our cardiologists have an exceedingly stable workforce as well. When you have good people that get along, the focus is entirely on outcomes.”

Riley has an integrated care model, with a floor dedicated to cardiovascular care. That includes a dedicated surgical/cardiology/cardiovascular intensive care unit (ICU), cardiovascular nursing, and cardiovascular anesthesia staff members. Riley is one of the few places in the country to have an embedded cardiac newborn ICU pod built into the heart center, according to Turrentine.

“The floor is designed in an integrated way so that care delivery is standardized and is modeled in a way that we can adopt best practices,” he says. “For example, on 2 occasions we’ve gone well over 500 days straight without a central line-associated bloodstream infection.”

Christopher A. Caldarone, MD, chief of Congenital Heart Surgery at Texas Children’s Hospital, Houston: Texas Children’s Hospital has one of the highest volume centers for congenital heart surgery in North America, according to Caldarone.

“A small center can perform as well as a large center. Nevertheless, having high volume helps us to do well because there’s a lot of practice within the team. Rare lesions are encountered more frequently and therefore the group is more familiar with dealing with them than might be possible at a smaller institution,” he says.

Texas Children’s also has a well-orchestrated, team-based system for surgical decision-making in which a large group of clinicians in multidisciplinary conferences review every surgical decision for every patient. On elective patients, it’s typically done twice to make sure the patients obtain the maximum benefit of the group’s collective expertise.

“I think we have a lot of very experienced clinicians and rigorous processes for making high quality surgical decisions,” Caldarone says. “I’m not talking about just the surgeons. We depend upon highly experienced cardiologists, intensivists, cardiac anesthetists, and nurses. A well-organized team will outperform a group of individuals practicing in isolation, and that’s an important part of delivering high-quality care.”

Daniel Velez, MD, division chief of Cardiothoracic Surgery at Phoenix Children’s Hospital and co-director of the Phoenix Children’s Heart Center, Arizona: This is the sixth consecutive year that Phoenix Children’s Heart Center has received 3 stars. It’s a high-volume institution. Surgeons there performed more than 600 cardiac surgeries in 2018, according to Velez.

“We perform all levels of complexity-stat categories 1 through 5. We have a very robust heart transplant program and a strong mechanical-assist device program,” Velez says. “When you do 500-plus operations a year, it’s hard not to have the high-level complex patients. That’s how we have been able to show that we’re at the top of our game by performing when operating on those patients who are not expected to make it.”

In the mix of complex surgeries at the Phoenix Children’s Heart Center: neonatal repairs; the use of surgically implanted transcatheter valves; tricuspid valve repairs using the Cone procedure; heart transplantation; and medical-assist devices. “Last year, we implanted the youngest patient in the world (10 years old) with the new 50-cc total artificial heart,” Velez says.

Mark S. Bleiweis, MD, director, University of Florida (UF) Health Congenital Heart Center, UF Health Shands Children’s Hospital, Gainesville: “We’re a program that uses a multidisciplinary approach, with experts in cardiac surgery, cardiology, anesthesia, and critical care,” Bleiweis says. “It’s a very specialized team that can take care of the entire array of and spectrum of CHD, including premature neonates to adults with CHD, as well as transplant patients. We exceed the expectations in outcomes even though we have a very complex practice. We have a very high survival rate for all comers with CHD.”

Bleiweis says UF Health Shands has one of the largest pediatric transplant programs in the country and one of the largest ventricular-assist device programs for pediatrics in the United States. He and his cardiothoracic surgeon colleagues operate on a high proportion of neonates and infants with hypoplastic left heart syndrome. “We’ve achieved outstanding outcomes with that disease, which is a very complicated and difficult disease to manage,” he says.

The center’s dedication to having a seamless multidisciplinary approach is key to achieving better-than-expected mortality and other outcomes, according to Bleiweis. “You can imagine when you have a smooth system where the cardiologists, surgeons, ICU doctors, and anesthesiologists are all on the same page. We’re not in separate departments, which leads to the best outcomes and care for our patients,” he says.

download issueDownload Issue : Vol 36 No 5