Test de umbral de desfibrilación no muestra beneficio clínico a largo plazo en pacientes sometidos a implante de Resincronizador + Desfibrilador
Defibrillation threshold testing fails to show clinical benefit during long-term follow-up of patients undergoing cardiac resynchronization therapy defibrillator implantation
Yoav Michowitz1,*, Nicolas Lellouche2, Tahmeed Contractor1, Tara Bourke1, Isaac Wiener1, Eric Buch1, Noel Boyle1, Malcolm Bersohn1 and Kalyanam Shivkumar1 + Author Affiliations 1UCLA Cardiac Arrhythmia Center, Ronald Reagan UCLA Medical Center, David Geffen School of Medicine at UCLA, A2-237 CHS, 10833 Le Conte Avenue, Los Angeles, CA 90095, USA 2Hospital Henri Mondor APHP, INSERM U841, Creteil, France *↵Corresponding author. Tel: +1 310 206 6433; fax: +1 310 794 6492, Email: [email protected] Received November 2, 2010. Accepted December 21, 2010.
Abstract Background The utility of defibrillation threshold testing in patients undergoing implantable cardioverter–defibrillator (ICD) implantation is controversial. Higher defibrillation thresholds have been noted in patients undergoing implantation of cardiac resynchronization therapy defibrillators (CRT-D). Since the risks and potential benefits of testing may be higher in this population, we sought to assess the impact of defibrillation safety margin or vulnerability safety margin testing in CRT-D recipients.
Methods and results A total of 256 consecutive subjects who underwent CRT-D implantation between January 2003 and December 2007 were retrospectively reviewed. Subjects were divided into two groups based on whether (n= 204) or not (n= 52) safety margin testing was performed. Patient characteristics, tachyarrhythmia therapies, procedural results, and clinical outcomes were recorded. Baseline characteristics, including heart failure (HF) severity, were comparable between the groups. Four cases of HF exacerbation (2%), including one leading to one death, were recorded in the tested group immediately post-implantation. No complications were observed in the untested group. After a mean follow-up of 32 ± 20 months, the proportion of appropriate shocks in the two groups was similar (31 vs. 25%, P = 0.49). There were three cases of failed appropriate shocks in the tested group, despite adequate safety margins at implantation, whereas no failed shocks were noted in the untested group. Survival was similar in the two groups.
Conclusion: Defibrillation efficacy testing during implant of CRT-D was associated with increased morbidity and did not predict the success of future device therapy or improve survival during long-term follow-up.
Abstract obtenido de EUROPACE mayo 2011, 13 (5)