Outcomes of permanent pacemakers and implantable cardioverter-defibrillators in an adult congenital heart disease population

Background

Brady- and tachyarrhythmias commonly complicate adult congenital heart disease (ACHD). Permanent pacemakers (PPMs) or implantable cardioverter–defibrillators (ICDs) are often utilised to prevent morbidity or mortality related to arrhythmia, but can also be associated with significant morbidity themselves.

Methods

We analysed outcomes from patients in our comprehensive ACHD database who were seen at least twice since 2000 and once since 2018. Of 1953 ACHD patients, 134 had a PPM and 78 had an ICD (47 for primary and 31 for secondary prevention).

Results

For PPM patients, 41% had a pacing percentage below 33%, 13% had 33–66%, and 46% had above 66%. One fifth required PPM upgrade, most to cardiac resynchronisation therapy, the rest to ICD. There were 33 appropriate ICD shocks in 15 patients (19%) and 34 inappropriate shocks in 13 patients (17%) over a median follow up of 4.6 years (IQR 0.9–8.3 years). Anti-tachycardia pacing was delivered appropriately for 28% of patients and inappropriately for 9%.

Apart from inappropriate therapy, one third of PPM and ICD patients had other device-related complications. Acute PPM complications included lead dysfunction requiring revision (2%), pneumothorax (2%), pleural effusion (2%) and pocket infection (2%). ICDs were also acutely complicated by lead dysfunction (4%) as well as pocket hematoma (3%). The most common long-term complication overall was lead dysfunction, affecting one sixth of both PPM and ICD patients. Finally, the rate of device insertion increased significantly with disease severity.

Conclusions

Anti-arrhythmic devices can be lifesaving in ACHD patients, but inappropriate therapy and device-related complications are very common.