The learning curve associated with the introduction of the subcutaneous implantable defibrillator.
OBJECTIVE
The subcutaneous implantable cardioverter defibrillator (S-ICD) was introduced to overcome complications related to transvenous leads. Adoption of the S-ICD requires implanters to learn a new implantation technique. The aim of this study was to assess the learning curve for S-ICD implanters with respect to implant-related complications, procedure time, and inappropriate shocks (IASs).


RESULTS
In a pooled cohort from two clinical S-ICD databases, the IDE Trial and the EFFORTLESS Registry, complications, IASs at 180 days follow-up and implant procedure duration were assessed. Patients were grouped in quartiles based on experience of the implanter and Kaplan-Meier estimates of complication and IAS rates were calculated. A total of 882 patients implanted in 61 centres by 107 implanters with a median of 4 implants (IQR 1,8) were analysed. There were a total of 59 patients with complications and 48 patients with IAS. The complication rate decreased significantly from 9.8% in Quartile 1 (least experience) to 5.4% in Quartile 4 (most experience) (P = 0.02) and non-significantly for IAS from 7.9 to 4.8% (P = 0.10). Multivariable analysis demonstrated a hazard ratio of 0.78 (P = 0.045) for complications and 1.01 (P = 0.958) for IAS. Dual-zone programming increased with experience of the individual implanter (P < 0.001), which reduced IAS significantly in the multivariable model (HR 0.44, P = 0.01). Procedure time decreased from 75 to 65 min (P < 0.001). The complication rate and procedure time stabilized after Quartile 2 (>13 implants).


CONCLUSIONS
There is a short and significant learning curve associated with physicians adopting the S-ICD. Performance stabilizes after 13 implants.
Academic Medical Center, Amsterdam, The Netherlands.
Reinoud E
RE
Knops
Academic Medical Center, Amsterdam, The Netherlands t.f.brouwer@amc.nl.
Tom F
TF
Brouwer
Russells Hall Hospital, Dudley, UK.
Craig S
CS
Barr
Erasmus Medical Center, Rotterdam, The Netherlands.
Dominic A
DA
Theuns
St Antonius Ziekenhuis, Nieuwegein, The Netherlands.
Lucas
L
Boersma
Ohio State University, Columbus, OH, USA.
Raul
R
Weiss
Na Homolce Hospital, Prague, Czech Republic.
Petr
P
Neuzil
Medisch Spectrum Twente, Enschede, The Netherlands.
Marcoen
M
Scholten
The Heart Hospital, University College London, London, UK.
Pier D
PD
Lambiase
Emory University, Atlanta, GA, USA.
Angel R
AR
Leon
Auckland City Hospital, Auckland, New Zealand.
Margaret
M
Hood
Boston Scientific, Minneapolis, MN, USA.
Paul W
PW
Jones
Boston Scientific, Minneapolis, MN, USA.
Nicholas
N
Wold
Papworth Hospital NHS Foundation Trust, Cambridge, UK.
Andrew A
AA
Grace
Academic Medical Center, Amsterdam, The Netherlands.
Louise R A
LR
Olde Nordkamp
University of Chicago, Chicago, IL, USA.
Martin C
MC
Burke
D000328:Adult; D000368:Aged; D006348:Cardiac Surgical Procedures / Q000193:education*; D016208:Databases, Factual; D017147:Defibrillators, Implantable; D004554:Electric Countershock; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D053208:Kaplan-Meier Estimate; D059032:Learning Curve; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D016016:Proportional Hazards Models; D019919:Prosthesis Implantation / Q000193:education*; D012042:Registries; D012307:Risk Factors; D016896:Treatment Outcome
Complications; Implantable cardioverter-defibrillator; Inappropriate shock; Learning curve; S-ICD; Subcutaneous implantable cardioverter-defibrillator