Standardized mortality ratio in adults with congenital heart disease

The prevalence of adults with congenital heart disease (ACHD) is rising due to improved paediatric care. In parallel, updated data on prognosis in adult life are needed.

The aim was to calculate the standardized mortality ratio (SMR) and death rates in ACHD compared to the general population.

Data were obtained from the national register of congenital heart disease. The general Swedish population served as a reference. SMR was calculated as the ratio between observed and expected deaths. 9089 patients (median age 28 years, interquartile range [IQR] 20-45, 47% females) were followed for a median of 8 years (IQR 4-14). 525 deaths occurred during observation. The SMR increased by lesion complexity: atrial septal defect [1.3 (95% CI: 1.1-1.5)]; ventricular septal defect [2.0 (1.4-2.7)]; congenital aortic valve disease [2.2 (1.6-2,9)]; Ebstein's anomaly [3.2 (1.8-5.2)]; tetralogy of Fallot [3.8 (2.6-5.2)]; congenitally corrected transposition of the great arteries [5.6 (2.9-9.6)]; Eisenmenger syndrome [8.7 (5.5-13.1)]; transposition of the great arteries with a previous atrial redirection operation [12.3 (6.8-20.1)]; and Fontan physiology [22.5 (12.5-37.0)]. Calculations were also performed by severity (mild, moderate, and severe) and age by six age groups. SMR was generally higher in younger age, and the difference in mortality from the general population was estimated to be lower for older age groups. The mortality distribution and death rate per 1000 person-years have also been calculated for each lesion.

The mortality in ACHD remains increased compared to the general population and reflects the severity of the lesion. In higher ages, the observed mortality is more in line with the general population, probably because of survival of the least affected patients, and that few persons with severe lesions have reached advanced age.