(P072) INFECTIVE ENDOCARDITIS IN ADULTS WITH CONGENITAL HEART DISEASE (IE-ACHD): A REGISTRY

Background: About 1% of adults live with congenital heart disease (CHD), with an increasing prevalence as life expectancy and chronic management improves. Infective endocarditis (IE) is an important cause of morbidity and mortality in this population.

In 2007, the American Heart Association (AHA) narrowed antibiotic prophylaxis recommendations to include only those at high risk of developing IE: patients with prosthetic cardiac valves, previous bacterial endocarditis, complex cyanotic congenital heart disease, and surgically constructed pulmonary shunts or conduits. Notably, the guidelines removed the recommendation for antibiotic prophylaxis for the moderate risk group, which included most other adults with congenital heart disease (ACHD).

In the 8 years following guideline publication, antibiotic prophylaxis prescribing decreased as expected in the moderate risk group, but inappropriately decreased an estimated 20% in high-risk patients. Simultaneously, an increase in the incidence of IE was observed in both the moderate risk and high-risk groups (75% and 177%, respectively). Mortality from IE is higher in those with more complex ACHD.

METHODS AND RESULTS: The study is a prospective, multi-centre observational registry, with additional retrospective cases from 2017-2023 (Figure 1). Inclusion criteria are IE as diagnosed by Duke Criteria, ACHD by AHA/ACC Anatomical Classification, and informed consent for prospective patients. Prospective patients will be followed annually for 3 years after IE event to assess short- and longer-term outcomes; the most recent follow-up visit will be recorded for retrospective patients. Outcomes of interest include death, sepsis, new or worsening heart failure, thromboembolic events, valvular intervention (replacement or repair), and recurrent IE.

The objectives of the registry are as follows:
1. Determine the incidence of IE across the spectrum of ACDH in North America and identify cases in which antibiotic prophylaxis would have been beneficial.
2. Determine the morbidity and mortality of incident IE in ACHD.
3. Determine the predictors of adverse events among ACHD with IE.

Enrollment began in summer 2023; there are currently 40 participants in the registry across 3 sites. Eighteen sites across North America have signed on to participate, with ongoing recruitment of specialized ACHD centres and plans to expand to Europe and Australia/New Zealand.

Conclusion: With improving surgical and medical management, the complexity of ACHD patients is increasing and thus so is the importance of understanding the risks and outcomes of IE in this population. The IE-ACHD Registry will serve to collect longitudinal data, with plans to expand internationally.