Assessing Surgical Risk for Patients with ACHD

Research study background

The treatment of patients with congenital heart disease (CHD) has undergone significant advances in recent decades, resulting in more than 97% of patients with CHD living into adulthood. The population of patients with adult congenital heart disease (ACHD) now accounts for the majority of people living with CHD. Many adults with CHD require repeat surgical intervention during their lifetime. While there are many surgical risk tools for adults undergoing heart surgery, the development of these tools excluded adults with CHD, and they do not always perform well when applied to the ACHD population. Likewise, pediatric heart surgery risk assessment tools are not always suitable for the ACHD population. Recently, the Perioperative ACHD (PEACH) score was created specifically to assess surgical risk for adults with congenital heart disease undergoing heart surgery. This study looked to validate their results in a U.S. population.

The study looked at seven factors to validate the PEACH score, including:

• The New York Heart Association (NYHA) classification, which categorizes heart failure severity
• The adult congenital heart surgery (ACHS) score, a procedural risk-assessment tool used to predict in-hospital mortality in adults undergoing congenital heart disease surgeries
• Urgency
• Endocarditis
• Prior sternotomies
• Hemoglobin
• Kidney function

The research group used these factors to divide the cohort into three groups based on risk: low, intermediate and high. The retrospective study examined 516 adults with ACHD who were undergoing cardiac surgery at University of Colorado hospitals from 2010 to 2022. Researchers collected clinical data and outcomes to assess the accuracy of the PEACH score in prediction of post-operative morbidity and mortality.

Results

The PEACH score demonstrated good predictive accuracy with an area under the curve (AUC) score of 0.832 (1.0 is perfect accuracy). The PEACH score performed similarly or better when compared to two surgical risk predictive models from the Society of Thoracic Surgeons with the Adult Congenital Heart Surgery (ACHS) score AUC of 0.869 and the Society of Thoracic Surgeons-European Association for Cardio-Thoracic Surgery (STAT) score AUC of 0.769.

The study found that mortality rates increased for patients in the higher PEACH risk categories. There were nine deaths in the cohort, a mortality rate of 1.7%. No patients in the low-risk group died. There were six deaths in the intermediate-risk group (mortality rate of 2.6%) and three deaths in the high-risk group (mortality rate 7.3%). In addition, the research team looked to add new variables to the PEACH score in an effort to improve outcome prediction. They found that the addition of thrombocytopenia (platelet count below 150,000) to the score improved the AUC to 0.843, suggesting thrombocytopenia as a novel risk factor for post-operative mortality in ACHD patients.

The PEACH score also correlated with important post-operative morbidity, including longer hospital length of stay, post-operative bleeding requiring re-intervention, and higher 30-day readmission rates, suggesting the PEACH score’s use for post-operative risk beyond mortality alone.

Clinical implications

The PEACH score demonstrated good performance in predicting post-operative mortality and morbidity in adults with congenital heart disease undergoing cardiac surgery, supporting its use as a clinically meaningful tool for pre-operative risk assessment and patient counseling. Incorporating the PEACH score into routine surgical evaluation may improve risk stratification, facilitate patient counseling, and help identify individuals who may benefit from heightened peri-operative monitoring or targeted interventions.

Despite these encouraging findings, the study's retrospective single-center design may limit the generalizability of the results. Future prospective multicenter studies are needed to validate the PEACH score, refine its predictive performance, and determine whether incorporation of additional pre-operative risk factors can further enhance risk prediction in this complex and growing population.

Megan Soohoo, MD, was the senior writer of the study and says the team’s goal was to determine whether they could better predict which adults with congenital heart disease are at higher risk for complications after cardiac surgery in order to provide more personalized care.

“The PEACH score performed well in our study,” Dr. SooHoo says. “We're now incorporating it into our preoperative evaluations to help guide discussions with patients and families, identify those who may benefit from additional monitoring or resources and ultimately improve surgical outcomes."