OUTCOME OF SUPRAVENTRICULAR TACHYCARDIA IN INFANCY AFTER 4-YEAR FOLLOW-UP.

Editor

Supraventricular tachycardia (SVT) is the most common arrhythmia in children, with the majority of SVT episodes occurring in a structurally normal heart.

Although there is a broad spectrum of research on method of management and short-term outcomes of SVT prophylaxis-, there is little evidence on the long-term outcome of patients presenting with SVT. In fact, we were only able to locate one study of 15 patients.

METHODS

The ‘HeartSuite’ database from the Royal Belfast Hospital for Sick Children (RBHSC) included 55 patients who were diagnosed and admitted into RBHSC or referred to outpatients’ clinics across Northern Ireland.

Data were collected for children presenting with the first episode for infants under 1 year of age between 2006 and 2011 allowing at least 4 years’ follow-up.

RESULTS

The major finding was that 48/55 patients (87.3%) after review were discharged or able to live without medication. Of the 55 patients surveyed, 36 (65.5%) were discharged and 12 (21.8%) were still being followed up but on no medication. Only 6 (10.9%) were still on medication. There was one intervention for catheter ablation of the accessory pathway. There was no mortality.

DISCUSSION

The study suggests that a large number of patients presenting with the first episode in the first year were discharged after four years.

One retrospective review on the outcome for AVNRT (atrioventricular nodal re-entry tachycardia), a common form of SVT, in 15 patients also showed no mortality after 40+ months’ follow-up. 9/14 asymptomatic subjects (64.3%) were no longer on medication in their study which is significantly lower than our findings (87.3%) and 5 (35.7%) were still on medication after 21 months’ follow-up – higher than our figure of 10.9%. 2/15 in the study underwent radiofrequency ablation (13.3%), also higher than the 1.8% intervention rate we found. The small number of patients followed up in both studies may have contributed to these discrepancies. This study was also specific to patients diagnosed with AVNRT and it was published almost two decades ago.

Our study was on a small scale but specific to the population of Northern Ireland. The strength of this study is that there is at least a four-year follow-up for each subject, enabling us to provide information for the long-term outcome.

CONCLUSION

This study provides detailed information on SVT outcomes in Northern Ireland. It provides a larger sample of patients than previously reported for over a similar length of time. This study may give doctors a clearer plan for paediatric SVT patients in relation to prognosis and duration of review.