The goal of our study was to show an increase in the number of interventional heart catheterisations in the last 14 years in the Referral Centre for Pediatric Cardiology of the Republic of Croatia. From January 1996 to December 2009 2379 children (51% male and 49% female) underwent invasive diagnostic procedures (mean age 4.1+3.8 years, range 1 day-20.5 years). In that period in 22.27% (2379/530) of the children a certain interventional procedure was performed. The number of interventional catheterisations increased from 20/160 (12.5%) in 1996 to 70/224 (31.25%) in 2009. Some interventional procedures were introduced before 1996 (Rashkind BAS, dilatation of pulmonary valve stenosis and myocardial biopsy), while other methods were introduced in the following order: dilatation of critical aortic stenosis in newborns and other ages from 1996, ductus Bottali closure from 1997, interatrial septal defect closure from 2000, native coarctation and recoarctation of the aorta from 2003. Of 530 interventional catheterisations involved in the study during the period of 14 years, there were 140 atrioseptostomias (26.4%), 80 pulmonary valve dilatations (15.1%), 58 aortic valve dilatations in older children (6.8%), 9 dilatations of critical aortic stenosis (1.7%), 58 dilatations of coarctation (10.9%) (of which 32 native and 26 recoarctations), 133 ductus Botalli closures (25.1%) (4 with PFM coils, 68 with Cook coils and 61 with Amplatzer Duct occluder). From 2000 interatrial septal defects were closed in 37 patients, 14 of which were closed with Cardioseal-STARflex system (37.84%) and 23 with Amplatzer device (62.16%). Myocardial biopsy was performed in 37 patients (7%) with 4-5 endomyocardial samples per patient (mainly from the left ventricle) so that we had 120 heart samples in total for further analysis. Hi2-test determined a constant rise in catheterisations in relation to the mean number (p<0.05) except for the years 1997 and 1998 when it was significantly lower than the average. A positive trend in the increase of interventional catheterisations was determined (p<0.005). The share of interventional catheterisations compared to diagnostic catheterisations was found to have statistically significantly increased (p<0.05) from 1996 to 2009. We conclude that in the observed period there is a slight increase in the overall number of catheterisations and a more intense increase of interventional catheterisations, particularly after 1999.