[Epidemiology of congenital heart diseases in Croatia--a multicenter nationwide study, 1995-2000].

Congenital heart diseases (CHD) comprise a group of different conditions seen in 0.55-1% of live births. Tendency to classify CHD according to Clark's pathogenic classification is based on the assumption that relatively few pathogenic mechanisms cause a wide spectrum of phenotypic forms of CHD. The aim of this study was to classify CHD according to Clark's classification and to calculate the prevalence rates of CHD in the Croatian population. We formed the Registry including all children with CHD born between 1995 and 2000 treated in paediatric cardiology departments in Croatia. In the study were enrolled 276,565 live births, 2,204 of them with CHD, 1.126 males and 1.078 females. Total birth prevalence was 8.0@1000. A statistically significant difference was found between CHD prevalence rates in several counties. The prevalence of all main pathogenic groups of CHD was constant in time, except for cell death defects where a twofold increase in the prevalence of muscular ventricular septal defect (VSD) was noted (0.6@1000-1.3@1000). The most common diagnosis was perimembranous VSD (19.0%), followed by atrial septal defect (ASD) type II (14.4%), muscular VSD (11.1%) and pulmonary stenosis (8.5%). This four diagnoses were composing more than 50% of all CHD diagnoses. Prevalence and diagnostic possibilities weren't different from those presented in the literature. However, differences in prevalence between the counties warrant further investigation into the development and aetiology of CHD.