RESUMEN
BACKGROUND: As implantable cardioverter-defibrillator technology evolves, clinicians and patients need reliable performance data on current transvenous implantable cardioverter-defibrillator systems. In addition, real-world reliability data could inform postmarket surveillance strategies directed by regulators and manufacturers. METHODS AND RESULTS: We evaluated Medtronic Sprint Quattro, Boston Scientific Endotak, and St Jude Medical Durata and Riata ST Optim leads implanted by participating center physicians between January 1, 2006 and September 1, 2012. Our analytic sample of 2653 patients (median age 65, male 73%) included 445 St Jude, 1819 Medtronic, and 389 Boston Scientific leads. After a median of 3.2 years, lead failure was 0.28% per year (95% CI, 0.19 to 0.43), with no statistically significant difference among manufacturers. Simulations based on these results suggest that detecting performance differences among generally safe leads would require nearly 10 000 patients or very long follow-up. CONCLUSIONS: Currently marketed implantable cardioverter-defibrillator leads rarely fail, which may be reassuring to clinicians advising patients about risks and benefits of transvenous implantable cardioverter-defibrillator systems. Regulators should consider the sample size implications when designing comparative effectiveness studies and evaluating new technology for preventing sudden cardiac death.
Asunto(s)
Desfibriladores Implantables , Vigilancia de Productos Comercializados , Anciano , Desfibriladores Implantables/efectos adversos , Desfibriladores Implantables/normas , Falla de Equipo/estadística & datos numéricos , Análisis de Falla de Equipo , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios RetrospectivosRESUMEN
BACKGROUND: Riata and Riata ST leads (St Jude Medical, Sylmar, CA) are prone to failure. There are no independent multicenter reports regarding Riata or Riata ST lead performance. OBJECTIVE: To conduct a retrospective multicenter study of Riata and Riata ST leads that were implanted and followed at 7 centers. METHODS: The study included adults who received St Jude Medical Riata or Riata ST leads. Data for Quattro Secure leads were obtained from an earlier study. RESULTS: From 2002 to 2010, 1081 patients received a Riata (n = 774) or Riata ST (n = 307) lead. Follow-up was longer for Riata than Riata ST leads (4.2 ± 2.4 years vs 3.3 ± 1.7 years; P<.0001). During the study, 67 leads failed (6.2%), including 62 of 774 Riata (8.0%) and 5 of 307 Riata ST (1.6%) leads. Forty-seven of 67 lead failures (70.1%) were caused by electrical malfunction, and 20 lead failures (29.9%) were due to externalized conductors (ECs) that were electrically intact. Of 110 leads examined fluoroscopically, ECs were found in 26 of 81 Riata (32%) and 1 of 29 Riata ST (3.4%) leads. Of 26 Riata leads with ECs, 7 (27%) were malfunctioning. Riata leads had lower overall and malfunction free survival compared to Quattro leads (P<.0001), while Riata ST lead survival was not different (P = .422). CONCLUSIONS: The survival of Riata (but not Riata ST) leads was lower than Quattro leads; however, Riata ST leads had significantly shorter follow-up than Riata leads. ECs were common in Riata leads, and more than a quarter of Riata leads that had ECs were malfunctioning. Our observations suggest that systematic fluoroscopic examination of patients with Riata leads is appropriate.
Asunto(s)
Arritmias Cardíacas/terapia , Desfibriladores Implantables , Anciano , Diseño de Equipo , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Factores de Tiempo , Resultado del TratamientoRESUMEN
BACKGROUND: Riata and Riata ST leads (St Jude Medical, Sylmar, CA) were recalled in 2011. These leads are prone to externalized conductors. However, it is electrical malfunctions that may result in serious adverse events, including death. OBJECTIVE: To assess the deaths of patients with Riata and Riata ST leads that have been reported to the Food and Drug Administration to determine whether they were due to lead malfunction. A similar analysis was performed for Quattro Secure leads (Medtronic, Inc, Minneapolis, MN). METHODS: In February 2012, we searched the Food and Drug Administration's Manufacturers and User Facility Device Experience database for deaths associated with Riata, Riata ST, and Quattro Secure leads. A lead-related death was a sudden or unexpected death accompanied by evidence of lead malfunction; an indeterminate death was a death that was nonsudden or evidence of lead malfunction was not provided; a not lead-related death was a death that was nonsudden and/or there was no evidence that the lead contributed to the patient's demise. RESULTS: The Manufacturers and User Facility Device Experience database search found 133 deaths; of these, 22 were caused by Riata or Riata ST lead failure and 5 were caused by Quattro Secure lead failure. Riata and Riata ST lead failure deaths were typically caused by short circuits between high-voltage components. No death was due to externalized conductors. CONCLUSIONS: Riata and Riata ST implantable cardioverter-defibrillator leads are prone to high-voltage failures that have resulted in death. These failures appeared to have been caused by insulation defects that resulted in short circuiting between high-voltage components. Externalized conductors were not a factor in these deaths.
Asunto(s)
Arritmias Cardíacas/mortalidad , Desfibriladores Implantables , Electrodos Implantados , Causas de Muerte , Bases de Datos Factuales , Desfibriladores Implantables/estadística & datos numéricos , Conductividad Eléctrica , Diseño de Equipo , Falla de Equipo , Fluorocarburos , Humanos , Retirada de Suministro Médico por SeguridadRESUMEN
BACKGROUND: The Riata family of implantable cardioverter-defibrillator leads (St Jude Medical, Sylmar, CA) appears prone to a unique failure mechanism whereby the conductor cables wear through the silicone insulation from inside-out and are seen outside the lead body (externalized conductors). OBJECTIVE: To assess the extent of Riata lead damage associated with inside-out insulation defects and their clinical consequences. METHODS: In September 2011, we searched the U.S. Food and Drug Administration's Manufacturers and User Defined Experience medical device database for reports describing Riata lead failures that had been analyzed by the manufacturer. RESULTS: The Manufacturers and User Defined Experience search identified 105 leads that had inside-out insulation defects. Eight-French single-coil Riata leads accounted for a higher-than-expected proportion (25.7%) of the leads with this defect. A total of 226 insulation defects were found in the 105 leads (2.2 defects per lead), including 143 inside-out defects (1.4 defects per lead). The most common location of insulation defects was distal to the proximal coil (n = 108). Twenty-eight leads (26.7%) had inside-out insulation defects underneath the shocking coils. Of 43 leads whose cables were assessed for the integrity of the ethylene-tetrafluoroethylene cable coating, 22 (51.2%) were found to be abraded, exposing the conductor surfaces. On X-ray radiography or fluoroscopy, 7 leads were found to have externalized cables; 2 of these leads had no electrical abnormalities, while 4 exhibited noise or increased impedance. Inappropriate shocks were experienced by 31 of the 105 patients (29.5%). CONCLUSION: Riata leads that have inside-out insulation defects often have multiple defects, including additional inside-out abrasions along the body of the lead and beneath the shocking coils. Eight-French single-coil Riata models may be more prone to externalized cables than are dual-coil and 7-F designs. Externalized cables are but one manifestation of interior insulation damage. Our findings question the durability of the ethylene-tetrafluoroethylene cable coating on exposed cables.