Pediatric Cardiac Surgery Outcomes

Hearing that your child needs heart surgery can be overwhelming. At the Heart Institute at Children’s Hospital Colorado, our caregivers understand the anxiety and stress that can come with a serious diagnosis. We’re here to guide you throughout your child’s care, from diagnosis to treatment and beyond.

In our history, we’ve cared for thousands of infants, children, teens and even adults with a vast variety of congenital heart defects (CHDs). As the largest pediatric heart surgery program in the region, we have performed more than 500 heart surgeries every year since 2017. Our highly specialized surgeons take on the most complex heart problems and achieve some of the best outcomes in the nation.

It’s all in support of the measure that matters most: the long and productive lives our patients go on to lead.

What are pediatric cardiac surgery outcomes?

In the medical world, the term “outcomes” means “success rates.” Many – but not all – pediatric cardiology centers measure and report their surgical outcomes to help parents make the best decision about where to take their child for heart surgery.

Here, we evaluate our success by monitoring and comparing our cardiac surgery statistics with other top pediatric hospitals. We also routinely check and publish other quality and patient safety metrics and heart transplant outcomes to ensure that families have the latest information when deciding who should care for their child.

Why transparency matters

We believe that families have the right to know every heart surgery program’s outcomes. Our Heart Institute is the only pediatric heart surgery program in Colorado and one of the few in our region to publicly report our cardiac surgery outcomes data. This transparency is one of the keys to our success as one of the best hospitals for congenital heart surgery in the country.

When researching heart surgery programs, parents should look for multiple outcome measures, such as total survival, survival by surgical complexity and length of stay, and consider these statistics together. No single metric should stand alone.

View some of the many things we measure and see our latest outcomes data below.

Open heart surgery survival rates

Heart surgery programs typically report their overall survival rate as well as survival rates based on the complexity of the surgery.

What we measure:

The percentage of heart surgery patients who survive their open heart surgery.

At Children’s Colorado, our overall survival rate for all cardiac surgery patients, regardless of how complex the surgeries are, is 97.6%. This is slightly higher than the national average that the Society of Thoracic Surgeons (STS) reported, which was 97.4%.

Source: Internal data, July 2017 through June 2021

What it means:

Having a higher survival rate indicates that a pediatric heart center is more experienced and better equipped for congenital heart surgery, and that fewer patients pass away during or after surgery.

Some heart centers take more complicated cases than others, which is why it’s important to also compare survival rates by complexity and type of defect.

Cardiac surgery survival rates by complexity

Some congenital heart defects are more complex than others. And because there are so many types of heart defects, no pediatric heart program will see the exact same defects each year.

The Society of Thoracic Surgeons (STS), the organization with the largest congenital heart surgery database, organizes the types of surgeries into five categories, which are referred to as “STAT categories” so they are easier to compare.

What are STAT categories?

STAT categories classify heart surgeries into groups based on how risky or complex they are. The STAT 1 category indicates surgeries with the lowest risk of death, while the STAT 5 category indicates the surgeries with the highest risk of death. A hospital that has a high survival rate for STAT 5 cases indicates success at handling unpredictable situations during the operation and during recovery.

What are risk-adjusted rates?

To help compare programs, the STS reports what are called “risk-adjusted” rates. This is a statistical evaluation developed by STS that predicts a patient’s risk of undergoing surgery. This evaluation attempts to include patient-related risk factors prior to surgery, such as age, weight and genetic abnormalities, in addition to the patient’s surgical risk. Using this method, STS compares the actual patient outcomes (observed outcomes) to expected outcomes (those predicted by the statistical model). Ultimately, a heart center should strive to have observed survival rates that are the same or higher than the expected survival rates.

Newborn cardiac surgery survival

Performing heart surgery on newborn babies is more challenging due to the young age and small size of the patients. By comparing newborn survival rates along with STAT category, parents can get an idea of how well the surgeons perform in the most challenging cases.

Newborn survival by STAT category

What we measure:

We compare our survival rates for newborn patients with national averages by the complexity of the surgery.

HIGHER IS BETTER

Source: Society of Thoracic Surgeons data from July 2017 through June 2021. Society of Thoracic Surgery (STS) is the largest congenital heart surgery database and includes data from 103 North American hospitals. Data taken from the 2021 risk-adjusted report.

What it means:

At Children’s Colorado, our surgeons have extensive experience correcting heart defects in even the youngest patients — some just a few hours old. Our survival rates for STAT 1, STAT 2 and STAT 5 cases are higher than the national averages.

STAT 5 newborn survival

What we measure:

STAT 5 neonatal survival measures the percentage of babies with the most complex heart defects who survive their surgery and have been discharged from the hospital.

 HIGHER IS BETTER

What it means:

At Children’s Colorado, our surgical team specializes in some of the most complex cardiovascular procedures, with special expertise in surgical repair during the newborn period. Having a high STAT 5 survival rate means that the newborn babies we treat are more likely to survive their operation than the national average, even though we accept many more complex patients.

Newborn survival average across all STAT categories

What we measure:

We look at average survival rates for newborn patients and compare them to national averages across all STAT levels, regardless of the level of surgical complexity.

 HIGHER IS BETTER

What it means:

Looking at an average across all STAT categories, Children's Colorado has a newborn survival rate of 94.4% compared to a national average of 92.5%.

Measuring congenital cardiac surgery survival

Open heart surgeries can be risky, and some deaths and complications are inevitable. Unfortunately, no program has a 100% survival rate. When researching a pediatric heart surgery center, it’s also important to compare the survival rate by patient age, type of operation and STAT category (complexity). This is because these rates can be much different than the program’s overall survival rate.

Cardiac surgery survival by procedure

Cardiac surgery programs can also report survival rates by each specific operation. These are called “benchmark operations,” and they are one of the ways surgical centers can compare outcomes. Note that these data do not include a patient’s specific risk factors prior to surgery.

In the table below, we report the total number of benchmark operations at Children’s Colorado, as well as the survival rates here compared to the national average.

Index case survival rates

What we measure:

Index case survival shows the percentage of patients who received a specific operation and were alive 30 days after their operation. It also includes patients who needed to be in the hospital longer than 30 days who were alive and successfully able to go home.

What it means:

For the majority of the open-heart surgeries listed above, our survival rates are higher than the national average.

It is challenging to compare outcomes by procedure alone. The procedure-alone data does not include important health-related factors such as age, other health conditions (called comorbidities), and genetic conditions that can make procedures riskier. This is why pediatric heart surgery programs should report a wide range of outcomes, including how well patients do when they are at higher risk due to other health conditions.

About the data:

This data is taken from surgeries that took place between July 2017 and June 2021. We are comparing this data to other organizations that do at least 10 surgeries in each category in order to show a more accurate comparison.

Survival by STAT category

Survival of all age groups by STAT category

What we measure:

There are five STAT categories for congenital heart surgeries and they are based on the likelihood of mortality with STAT 1 having the lowest chance and STAT 5 having the highest chance. We are able to compare our current STAT category surgery survival rate with the outcomes from the latest STS report.

HIGHER IS BETTER

Source: Society of Thoracic Surgeons data from July 2017 through June 2021. Society of Thoracic Surgery (STS) is the largest congenital heart surgery database and includes data from 103 North American hospitals. Data taken from the 2021 risk-adjusted report.

What it means:

For the highest risk surgeries (STAT 5), we perform consistently better than the expected outcome and the national average. Looking at all five STAT categories, Children's Colorado has a combined average survival rate of 97.6% compared to a national average of 97.4%

Survival of all age groups for STAT 5 category

What we measure:

STAT 5 survival outcomes measures the percentage of patients with the most complex heart defects who survive their surgery and have been discharged from the hospital.

HIGHER IS BETTER

Source: Society of Thoracic Surgeons data from July 2017 through June 2021. Society of Thoracic Surgery (STS) is the largest congenital heart surgery database and includes data from 103 North American hospitals. Data taken from the 2021 risk-adjusted report.

What it means:

For the highest risk surgeries (STAT 5), we perform consistently better than the expected outcome and the national average. For these complex surgeries, Children's Colorado has a survival rate of 93.6% compared to a national average of 88.4%

Average length of stay

By comparing the average length (LOS) of stay between hospitals, parents can learn which programs are best equipped to care for their child. The longer a child stays in the hospital after surgery, the more likely they are to have complications.

Average postoperative LOS (days) by benchmark procedure: Children's Colorado mean vs STS aggregate rate

What we measure:

The chart below shows the average number of days that children stay in the hospital for heart surgery by benchmark procedure.

Source: Society of Thoracic Surgeons data from July 2017 through June 2021. Society of Thoracic Surgery (STS) is the largest congenital heart surgery database and includes data from 103 North American hospitals. Data taken from the 2021 risk-adjusted report.

Adjusted days	Observed days	Expected	O/E ratio
16.5 days	15.9 days	16.2 days	0.98

Source:  Pediatric Cardiac Critical Care Consortium (PC4), from July 1, 2019 through June 30, 2022. 

What it means:

The number of observed days (postoperative length of stay) are equal to the amount of days we expect a patient to stay (expected days). We believe this is an excellent result, given our expertise in caring for the most complex conditions and delivering complex surgical treatment. For all STAT categories and for the highest risk surgeries on our most complex patients, our outcomes are better than the national average. This means our patients receive high-quality care before, during and after surgery to help them go home sooner.

Median LOS (days) by STAT category

What we measure:

The chart below shows the median number of days that children stay in the hospital for heart surgery by STAT category (STAT 1 being least complex and STAT 5 being most complex).

LOWER IS BETTER

Source: Society of Thoracic Surgeons data from July 2017 through June 2021. Society of Thoracic Surgery (STS) is the largest congenital heart surgery database and includes data from 103 North American hospitals. Data taken from the 2021 risk-adjusted report.

What it means:

For the least complex surgeries (STAT 1), the number of observed days (postoperative length of stay) for half of our patients was less than 4 days, while for the other half, it was more than 4 days. This is compared to a national median of 9.08 days. For the most complex surgeries (STAT 5), the number of observed days (postoperative length of stay) for half of our patients was less than 39 days, while for the other half, it was more than 39 days. This is compared to a national median of 51.16 days.

Pediatric heart surgery volumes

When it comes to congenital heart surgery, volume matters. Studies show that kids who need heart surgery do better when they are treated by medical teams that perform a high number (or volume) of surgeries. This is because surgeons in high-volume centers get more experience and see a wider range of heart defects than surgeons who perform only a handful of surgeries per year.

Performing hundreds of surgeries each year indicates that the hospital is a high-volume center and is likely to have better patient outcomes. This is particularly true for patients with complex heart defects.

Number of heart surgeries performed at Children’s Colorado

What we measure:

Surgical volume indicates the number of heart surgeries performed at a hospital.

Cardiopulmonary bypass indicates when a patient has to be connected to a machine that does the work of the heart and lungs while surgeons repair the heart. These surgeries are more complex than those without cardiopulmonary bypass.

Cardiac surgery volume

Operation type	2017	2018	2019	2020	2021
Cardiopulmonary bypass	338	326	376	373	386
No cardiopulmonary bypass	118	121	134	192	191
Other	57	68	87	118	101
Total	513	515	597	683	678

STS data: Children's Colorado 4-year operative mortality rate is 2.44%

Source: Society of Thoracic Surgeons data from July 2017 through June 2021. Society of Thoracic Surgery (STS) is the largest congenital heart surgery database and includes data from 103 North American hospitals. Data taken from the 2021 Risk Adjusted Report.

What it means:

Children’s Colorado is a high-volume cardiac surgery center, performing more than 500 surgeries each year for patients with congenital heart disease. We also perform hundreds of surgeries with cardiopulmonary bypass each year. This means we have the team, the experience and the facilities to treat kids, teens and even adults with a wide variety of congenital heart defects.