Patients with adult congenital heart disease (ACHD) have worse outcomes in cardiac intensive care units (CICUs), particularly a high rate of readmissions and mortality, according to a new study published April 30 in JACC: Advances.

In this retrospective cohort study, Luke J. Burchill, MBBS, PhD, et al., analyzed data from 12,428 unique CICU admissions at Mayo Clinic from 2007 to 2018 (including patients post percutaneous transcatheter procedure but not post open cardiac surgery). Of these admissions, 253 patients (2.0%) had ACHD (53% women, median age 42 years, 91% White), with 103 patients (41%) classified as severe; 36% had a critical care diagnosis (CCD) during admission (including shock, cardiac arrest, sepsis and respiratory failure) and 33% had critical care therapies (CCTs) (defined as use of vasoactive agents, including inotropes or vasopressors, invasive mechanical ventilation, renal replacement therapy or temporary mechanical circulatory support) during the CICU stay.

Heart failure (HF) was the primary admission diagnosis for the ACHD group in more than half of cases (56%), followed by a CCD. Patients with ACHD, compared with those without, admitted to the CICU were typically younger, more likely to be women and have fewer comorbidities, and to have HF or atrial and ventricular arrhythmias.

The primary endpoint was all-cause in-hospital mortality, and secondary endpoints included all-cause one-year mortality and hospital readmission to a Mayo Clinic facility at 30 days and one year.

Results showed that more than half of patients with ACHD admitted to the CICU died or were readmitted within one year. In-hospital mortality occurred in 22 patients (9%) with ACHD. In those with ACHD vs. those without, one-year survival was 64% vs. 88% (p<0.001) for patients with CCD and 69% vs. 85% for those with CCT (p=0.001). The authors note that CCD and CCT surpass severity or type of ACHD in predicting inpatient mortality.

Multivariable adjustment revealed that in-hospital mortality was higher among those with ACHD (adjusted odds ratio, 1.76; p=0.04), as was one-year mortality (adjusted hazard ratio, 1.42; p=0.02). Within one year, 44% of hospital survivors were readmitted to the hospital and 15% were readmitted within 30 days.

"The prognosis for ACHD patients who survive their hospital stay is concerning, particularly for those with critical illness, highlighting the need for targeted strategies to improve both short-term and long-term outcomes for ACHD patients requiring critical care," write Burchill, et al., noting that, "As the ACHD population ages, around 16% will require an ICU admission by the age of 40 years."