Long-term performance of the St Jude Riata 1580-1582 ICD lead family.

OBJECTIVE

Safety concerns about the Riata ICD shock lead were recently raised, with insulation failure due to conductor externalisation. Its incidence and presentation were assessed, and predictors of insulation failure and lead survival of the Riata 1580-1582 were studied, retrospectively, before the official recall.

METHODS

All 374 patients at the Erasmus Medical Center between July 2003 and December 2007 with a 1580, 1581 or 1582 shock lead.

RESULTS

The majority of the patients were male (78 %), with a median age of 60 years (IQR 52-70); primary prevention in 61 %. Median follow-up was 60.3 months (IQR 35.5-73.2), with 117 (31 %) patients dying. Electrical abnormalities (mainly noise, 65 %) were observed in 20/257 patients (7.8 %). Definite conductor externalisation was confirmed with fluoroscopy or chest X-ray in 16 patients, and in one after extraction. One patient presented with a drop in the high-voltage impedance trend with a short circuit of the ICD system during defibrillation testing, and needed to be shocked externally. In 8 more patients, conductor externalisation was found during an elective procedure. No predictors of externalisation could be found, except for the use of single coil (p = 0.02). Median time to conductor externalisation was 5 years (IQR 3.1-6.2). Lead externalisation was observed in 5.4 % (95 % CI 3.1-9.3) at 5 years and 22.7 % (95 % CI 13.6-36.6) at 8 years.

CONCLUSION

A high incidence of insulation defects associated with conductor externalisation in the Riata ICD lead family is observed. The mode of presentation is diverse. This type of insulation failure can lead to failure of therapy delivery.