title: [Is the determination of the defibrillation threshold in patients with an implantable cardioverter-defibrillator still required?].
abstract: BACKGROUND
  Intraoperative testing of implantable cardioverter-defibrillators (ICDs) is time consuming and associated with risks. In the present study, we elucidated whether the initial implantation of an ICD with high energy output makes intraoperative defibrillation threshold testing (DFTT) unnecessary even though antiarrhythmic (AA) therapy is needed in the future.
  
  
  METHODS
  A total of 111 patients (94 men, 17 women) receiving an ICD with subsequent AA therapy (mexiletine, amiodarone, sotalol, flecainide) were analyzed retrospectively. DFT was performed during ICD implantation and after AA drug therapy. In a second step, DFT results from the study cohort were analyzed for implantation of virtual ICDs with either low (≤ 30 J, LOD), intermediate (34 J, IOD), or high energy output (36 J, HOD).
  
  
  RESULTS
  In the study cohort, all patients reached the safety margin (SM) of 10 J between DFT and maximal shock energy of the ICD. After loading of AA agents, 6 patients (12%) with a LOD, 3 patients (11%) with an IOD, and 3 (13%) patients with a HOD failed the 10 J SM. Using virtual ICDs, 6 (5.5%) patients with a LOD, 1 patient (1%) with an IOD, and no patients with a HOD would have failed the 10 J SM. After loading of AA agents, 18 patients (16%) with a virtual LOD, 12 patients (10.8%) with an IOD, and still 9 patients (8%) with a HOD would have failed the 10 J SM.
  
  
  CONCLUSIONS
  Our results demonstrate that the 10 J SM would have been achieved intraoperatively in all patients with virtual HOD ICDs. Thus, determination of the DFT during implantation does not seem to be obligatory. However, in patients receiving AA agents, DFT testing is still required.
authors.affiliation: Abteilung für Kardiologie, Angiologie und Pneumologie, Universitätsklinikum Heidelberg, Heidelberg, Germany.
authors.forename: M
authors.initials: M
authors.lastname: Licka
authors.forename: L
authors.initials: L
authors.lastname: Jahn
authors.forename: K
authors.initials: K
authors.lastname: Kelemen
authors.forename: F
authors.initials: F
authors.lastname: Voss
authors.forename: K
authors.initials: K
authors.lastname: Trappe
authors.forename: R
authors.initials: R
authors.lastname: Becker
authors.forename: O
authors.initials: O
authors.lastname: Bikou
authors.forename: M
authors.initials: M
authors.lastname: Hauck
authors.forename: M
authors.initials: M
authors.lastname: Koch
authors.forename: H A
authors.initials: HA
authors.lastname: Katus
authors.forename: A
authors.initials: A
authors.lastname: Bauer
mesh_terms: D001281:Atrial Fibrillation / Q000175:diagnosis* / Q000453:epidemiology / Q000517:prevention & control*; D017147:Defibrillators, Implantable / Q000706:statistics & numerical data*; D004056:Differential Threshold; D004554:Electric Countershock / Q000379:methods / Q000706:statistics & numerical data; D004562:Electrocardiography / Q000379:methods / Q000706:statistics & numerical data*; D022062:Electrophysiologic Techniques, Cardiac / Q000706:statistics & numerical data*; D005260:Female; D005858:Germany / Q000453:epidemiology; D006801:Humans; D008297:Male; D008875:Middle Aged; D016343:Monitoring, Intraoperative / Q000706:statistics & numerical data*; D014600:Utilization Review
references.citation: J Cardiovasc Electrophysiol. 2000 Jul;11(7):736-40
references.pmid: 10921789
references.citation: Heart Rhythm. 2008 Mar;5(3):387-90
references.pmid: 18243813
references.citation: J Electrocardiol. 1998 Jan;31(1):31-7
references.pmid: 9533375
references.citation: N Engl J Med. 2005 Jan 20;352(3):225-37
references.pmid: 15659722
references.citation: J Am Coll Cardiol. 2008 Aug 12;52(7):551-6
references.pmid: 18687249
references.citation: N Engl J Med. 2002 Mar 21;346(12):877-83
references.pmid: 11907286
references.citation: Pacing Clin Electrophysiol. 2007 May;30(5):675-700
references.pmid: 17461879
references.citation: Anesth Analg. 1997 Aug;85(2):299-300
references.pmid: 9249103
references.citation: Am Heart J. 1994 Apr;127(4 Pt 2):978-84
references.pmid: 8160602
references.citation: J Cardiovasc Electrophysiol. 2000 Jul;11(7):741-3
references.pmid: 10921790
references.citation: Heart Rhythm. 2005 May;2(5):456-61
references.pmid: 15840466
references.citation: Circulation. 2006 Jul 11;114(2):104-9
references.pmid: 16818810
references.citation: J Am Coll Cardiol. 1998 Jun;31(7):1672-8
references.pmid: 9626850
references.citation: Anesth Analg. 1997 Jun;84(6):1186-92
references.pmid: 9174290
references.citation: N Engl J Med. 1996 Dec 26;335(26):1933-40
references.pmid: 8960472
references.citation: Cardiol J. 2007;14(5):463-9
references.pmid: 18651506
references.citation: Pacing Clin Electrophysiol. 1995 Jan;18(1 Pt 2):199-202
references.pmid: 7724399
references.citation: Pacing Clin Electrophysiol. 1997 Jun;20(6):1667-72
references.pmid: 9227765
references.citation: Circulation. 1992 Oct;86(4):1206-16
references.pmid: 1394927
references.citation: J Cardiovasc Electrophysiol. 1998 Aug;9(8):791-7
references.pmid: 9727657
references.citation: Circulation. 1992 Mar;85(3):1146-51
references.pmid: 1537112
references.citation: Circulation. 2002 Apr 30;105(17):2043-8
references.pmid: 11980683
references.citation: Int J Cardiol. 1999 Jun 1;69(3):271-9
references.pmid: 10402110
references.citation: Curr Cardiol Rep. 2002 Sep;4(5):434-40
references.pmid: 12169241
references.citation: J Am Coll Cardiol. 1998 May;31(6):1391-4
references.pmid: 9581739
references.citation: J Cardiovasc Electrophysiol. 1996 Mar;7(3):211-6
references.pmid: 8867295
references.citation: Pharmacotherapy. 1998 May-Jun;18(3):516-25
references.pmid: 9620103
references.citation: Pacing Clin Electrophysiol. 2003 Jan;26(1 Pt 1):44-8
references.pmid: 12685138
references.citation: Am J Cardiol. 1992 Oct 15;70(11):1023-7
references.pmid: 1414899
references.citation: N Engl J Med. 1997 Nov 27;337(22):1576-83
references.pmid: 9411221
references.citation: J Cardiovasc Electrophysiol. 2008 Apr;19(4):400-5
references.pmid: 18298512
references.citation: Arch Intern Med. 2001 Mar 12;161(5):649-55
references.pmid: 11231696
references.citation: Europace. 2005 Nov;7(6):509-15
references.pmid: 16216750