Objective: To find the incidence and risk factors for supraventricular tachyarrhythmia (SVT) occurring during cardiac catheterization at our institution.
Methods: Occurrence of SVT during diagnostic and interventional cardiac catheterization for children and adult with congenital heart disease (age 3.7±4.7 years, 54% male) between the year 2000-2004 was prospectively recorded. SVT was defined as tachyarrhythmia of non-sinus origin with narrow or similar QRS complex as during the sinus rhythm. The incidence and type of tachyarrhythmia was determined for each diagnostic category. Chart reviews were done in 2008 for arrhythmic events after the catheterization procedure.
Results: SVT occurred in 41 patients out of 835 catheterization procedures (incidence = 4.9%). The mechanisms were thought to be atrial flutter or atrial tachycardia (AT/AF) in 16, junctional tachycardia in 1 and reentry via the AV node (AVRT/AVNRT) in 24 patients. Age and sex were not associated with SVT occurrence. Patients with functional single ventricle were more likely to have SVT (mostly AVRT/AVNRT, incidence 13.4%, relative risk 3.5, p<0.001) and infants with PS were more likely to develop AT/AF during balloon valvuloplasty procedure (incidence 14%, relative risk 3.2, p<0.01). During follow-up, clinical tachyarrhythmia were rare, although the actual recurrence rate cannot be determined because many patients were taking medications with antiarrhythmic property (such as digoxin).
Conclusion: The diagnosis of single ventricle was a risk factor for SVT during diagnostic cardiac catheterization in children. Balloon pulmonary valvuloplasty in infant was a risk factor for AT/AF during the procedure. In our clinical setting, recurrence of SVT was rare.