Abstract Body (Do not enter title and authors here):
Introduction:
There has been a steady rise in the prevalence of hypertension in adults with congenital heart disease (ACHD) and is now comparable to the general population. The burden and impact of acute presentation with hypertensive crisis (HC) remains unclear in the ACHD population warranting further investigation.

Research Question:
To investigate the prevalence of hypertensive crisis amongst hospitalizations in the ACHD population and its related trends and outcomes.

Methods:
We utilized the National Inpatient Sample to identify adults ≥18 years between 2016 and 2022 with underlying congenital heart disease admitted with HC, including hypertensive urgency, hypertensive emergency and unspecified HC. ACHD patients were grouped into mild and moderate/great complexity heart disease for sub-group analysis. Trend analysis was performed. We performed a 2:1 propensity matching to control for relevant demographic and clinical variables when comparing outcomes with non-ACHD patients presenting with HC.

Results:
A total of 6,280 hospitalizations were identified for hypertensive crisis amongst ACHD patients, representing 1.1% of all hospitalizations amongst ACHD patients. The mean patient age was 57.9 years and 49.9% were female. Most prevalent comorbidities included coronary artery disease (53.6%), congestive heart failure (43.5%) and diabetes mellitus (36.1%). The hospitalization rate for HC in ACHD patients has been on a gradual rise, increasing from 0.76% of all hospitalizations in 2017 to 1.2% in 2022 (p trend 0.06). After propensity matching, ACHD patients had higher rates of STEMI compared to non-ACHD patients presenting with HC (3.9% vs 2.2%, p < 0.05). Additionally, ACHD patients also had a longer hospital stay (6.8 days vs 5.6 days, p < 0.05). The outcomes for mortality, stroke, and acute heart failure, were similar. In the subgroup analysis, patients with simple congenital heart disease had lower mortality compared to non-ACHD patients (0.98% vs 2.4%, p = 0.03).

Conclusion(s):
The overall prevalence of hypertensive crisis amongst hospitalizations in ACHD patients is low at 1% though demonstrating a gradual increase over the years. Patients with ACHD demonstrate worse STEMI and resource utilization outcomes including length of hospital stay. The higher occurrence of STEMI in ACHD patients emphasizes the growing need to investigate disease patterns and management of acquired heart diseases that may otherwise get overlooked in this unique subset of patients.