Incidence of and risk factors for catheterization-induced complete heart block in the pediatric cardiac catheterization laboratory.

BACKGROUND The majority of the literature on catheterization-induced heart block (CIHB) was published >30 years ago. The field of cardiac catheterization has evolved, performing more interventional compared with diagnostic cases. We sought to determine the incidence and risk factors of CIHB. METHODS AND RESULTS A catheterization database that records the occurrence of adverse events on all cases was queried for heart block. Additional retrospective data on event outcome were collected on patients who developed CIHB. Multivariable logistic regression modeling was used to identify risk factors of CIHB (odds ratio, 95% confidence interval). In a 6-year period, 6183 cases were performed. The median weight was 15.0 (7.0-47.0) kg, with 29% consisting of infants <1 year. A total of 72% involved complex congenital heart disease. One hundred thirty-five cases were complicated by CIHB (2.2%; 95% confidence interval, 1.9-2.6). Age <1 year (3.0; 2.2-4.3) and case duration ≥2 hours (3.4; 2.0-6.0) were risk factors of CIHB; cardiac anatomy and intervention performed were not. A total of 96% of CIHB recovered within 1 week but 6 patients underwent pacemaker placement (3 L-loop ventricles, 2 intracardiac devices, 1 double inlet-double outlet RV). Of these, 50% recovered atrioventricular nodal conduction within 1 month; 2 patients with L-loop ventricles and 1 patient with a left ventricular-to-right atrial device did not recover. CONCLUSIONS The incidence of CIHB in the pediatric cardiac catheterization laboratory is low at 2.2%. Risk factors include young age and long case duration. The recovery of atrioventricular nodal function after CIHB is high and follows a similar time course to that of postsurgical heart block.