Predictors of mortality in adult patients with congenital heart disease

Abstract

Background: Most patients with congenital heart disease (CHD) reach adulthood thanks to the successful efforts of cardiac surgeons. However, sudden cardiac deaths are significantly more prevalent in this population, and survival is reduced when compared to the general population. The aim of this study is to define the prognostic value of selected clinical parameters to predict mortality in adult CHD patients referred to the specialist outpatient centre. The following parameters were analyzed as potential predictors of long-term survival: complexity of heart defect, past surgical intervention, heart failure (functional class according to NYHA > I), cyanosis, age and gender.
Methods: We analyzed data gathered from 1,304 patients (568 male) aged 18 to 72 (mean 29.4 ± 10.6) between 1995 and 2004. Mean duration of follow-up was 3.52 ± 1.83 years.
Results: During follow-up, 29 deaths were recorded (2.2%). Higher mortality was found in the group of patients with complex as oppposed to simple CHD (28 [6.7%] vs. 1 [0.1%]; p = 0.00001), in subjects without surgical correction as opposed to those operated on (21 [6.1%] vs. 8 [0.8%], p = 0.00001). General survival was 99.1% at two years and 96.6% at five years. In univariate survival analysis, all single clinical variables except patient gender were associated with increased risk of death (p = 0.00001 for all). All patients who died presented with heart failure. In multivariate analysis, the independent predictor of mortality was cyanosis (heart rate 38.1). Complexity of lesion (heart rate 6.4) represented a relative risk factor.
Conclusions: Heart failure and cyanosis are negative predictors of survival in adult patients with CHD. Complexity of the lesion increases the relative risk of mortality. Past cardiac surgery is associated with better survival, but, as with age and gender, it is not a significant prognostic factor.