TITLE: Dose of Electrical Current for Biphasic Defibrillators for Synchronous Cardioversion in Patients with Tachyarrhythmia: Guidelines DATE: 5 May 2009 RESEARCH QUESTION: What recommendations exist for electrical current settings for biphasic defibrillators for elective synchronous cardioversion procedures in adults with unstable tachyarrhythmias? METHODS: A limited literature search was conducted on key health technology assessment resources, including PubMed, the Cochrane Library (Issue 2, 2009, University of York Centre for Reviews and Dissemination (CRD) databases, ECRI, EuroScan, international health technology agencies, and a focused Internet search. The search was limited to English language articles published between 2004 and April, 2009. Filters were applied to limit the retrieval to health technology assessments, systematic reviews, meta-analyses, randomized controlled trials, controlled clinical trials, observational studies, and guidelines. Internet links were provided, where available. The summary of findings was prepared from the abstracts of the relevant information. Please note that data contained in abstracts may not always be an accurate reflection of the data contained within the full article. RESULTS: Two randomized controlled trials (RCTs), one observational study, and five evidence-based guidelines were identified on the dose of electrical current for biphasic defibrillators for synchronous cardioversion in patients with tachyarrhythmias. No health technology assessments, systematic reviews, meta-analyses, or controlled clinical trials were identified. Additional articles that may be of interest have been included in the appendix. Disclaimer: The Health Technology Inquiry Service (HTIS) is an information service for those involved in planning and providing health care in Canada. HTIS responses are based on a limited literature search and are not comprehensive, systematic reviews. The intent is to provide a list of sources of the best evidence on the topic that CADTH could identify using all reasonable efforts within the time allowed. HTIS responses should be considered along with other types of information and health care considerations. The information included in this response is not intended to replace professional medical advice, nor should it be construed as a recommendation for or against the use of a particular health technology. Readers are also cautioned that a lack of good quality evidence does not necessarily mean a lack of effectiveness particularly in the case of new and emerging health technologies, for which little information can be found, but which may in future prove to be effective. While CADTH has taken care in the preparation of the report to ensure that its contents are accurate, complete and up to date, CADTH does not make any guarantee to that effect. CADTH is not liable for any loss or damages resulting from use of the information in the report. Copyright: This report contains CADTH copyright material and may contain material in which a third party owns copyright. This report may be used for the purposes of research or private study only. It may not be copied, posted on a web site, redistributed by email or stored on an electronic system without the prior written permission of CADTH or applicable copyright owner. Links: This report may contain links to other information available on the websites of third parties on the Internet. CADTH does not have control over the content of such sites. Use of third party sites is governed by the owners own terms and conditions.
HTIS reports are organized so that the higher quality evidence is presented first. Therefore, health technology assessment reports, systematic reviews, and meta-analyses are presented first. These are followed by randomized controlled trials, controlled clinical trials, observational studies, and evidence-based guidelines. OVERALL SUMMARY OF FINDINGS: The two RCTs that used biphasic cardioversion used varying doses. In the first, 50 Joules (J), 75J, 100J, 150J, and 200J were used in patients with atrial flutter. 1 The second used 120J, 150J, and 200J in patients with atrial fibrillation (AF). 2 The lower energies were found to be effective in one RCT 2 and were recommended in the other RCT. 1 The observational study in patients with AF used energies of 50J, 100J, and 150J and found 100J to be effective but the authors also stated that 50J may be appropriate for patients with a lower weight and body mass index. 3 American Heart Association (AHA) guidelines for electrical therapies (2005) state that the dose for biphasic cardioversion for supraventricular tachycardia (SVT) is not yet established, and report that the dose ranges between 100J and 120J in published studies. 6 The AHA guidelines for symptomatic bradycardia and tachycardia (2005) recommend a dose of 100J to 120J for biphasic synchronous cardioversion of atrial fibrillation. 7 For atrial flutter, SVT, or ventricular tachycardia (VT), the guidelines state that there is insufficient data to recommend a dose for biphasic cardioversion. The 2006 AHA states that there is not enough evidence to recommend a dose of energy for biphasic defibrillators for synchronized cardioversion in patients with VT, 4 which is consistent with the 2005 guidelines. 7 The 2006 guidelines suggest that in patients with SVT, 50J to 100J for biphasic synchronous cardioversion can be used. 4 The National Collaborating Centre for Chronic Conditions guidelines for Atrial Fibrillation do not state an actual dose for cardioversion, but state that the dose escalated from low energy to high energy. 5 The guideline also states that lower energy shocks are delivered with biphasic defibrillators. New Zealand guidelines for treatment of patients with AF and atrial flutter recommend 100J or 120J initially for biphasic cardioversion in patients with AF, then 150J to 200J. For atrial flutter, the recommended initial dose is 10J to 50J. 8 Overall, for biphasic defibrillators, the guidelines report a dose of 100J to 120J for patients with AF. 7,8 For patients with SVT, the most recent guideline recommends an energy dose of 50J to 100J. 4 One guideline for patients with atrial flutter recommends a energy dose of 10J to 50J. 8 No dose is recommended for VT due to insufficient evidence. 4,7 Dose of Electrical Current for Biphasic Defibrillators 2
REFERENCES SUMMARIZED: Health technology assessments Systematic reviews and meta-analyses Randomized controlled trials 1. Mortensen K, Risius T, Schwemer TF, Aydin MA, Koster R, Klemm HU, et al. Biphasic versus monophasic shock for external cardioversion of atrial flutter: a prospective, randomized trial. Cardiology 2008;111(1):57-62. PubMed: PM18239394 2. Siaplaouras S, Buob A, Rotter C, Bohm M, Jung J. Impact of biphasic electrical cardioversion of atrial fibrillation on early recurrent atrial fibrillation and shock efficacy. J Cardiovasc Electrophysiol 2004;15(8):895-7. PubMed: PM15333081 Controlled clinical trials Observational studies 3. Miracapillo G, Costoli A, Addonisio L, Severi S. Initial energy for biphasic external electrical cardioversion of atrial fibrillation. Ital Heart J 2005;6(9):757-60. PubMed: PM16212079 Guidelines and recommendations 4. American Heart Association. ACC/AHA/ESC 2006 guidelines for management of patients with ventricular arrhythmias and the prevention of sudden cardiac death: a report of the American College of Cardiology/American Heart Association Task Force and the European Society of Cardiology Committee for Practice Guidelines (Writing Committee to Develop Guidelines for Management of Patients With Ventricular Arrhythmias and the Prevention of Sudden Cardiac Death): developed in collaboration with the European Heart Rhythm Association and the Heart Rhythm Society. In: Circulation [database online] Dallas: AHA; 2006. Available: http://circ.ahajournals.org/cgi/reprint/114/10/e385 (accessed 2009 May 1). Note: see page e-412 5. National Collaborating Centre for Chronic Conditions. Atrial fibrillation: national clinical guideline for management in primary and secondary care. In: Clinical guideline [database online]. London: Royal College of Physicians; 2006. Available: http://www.nice.org.uk/nicemedia/pdf/cg036fullguideline.pdf (accessed 2009 May 1). 5.3 Electrical cardioversion with concomitant antiarrhythmic drugs (5.3.3) 6. American Heart Association. Electrical therapies: automated external defibrillators, defibrillation, cardioversion, and pacing. In: American Heart Association guidelines for cardiopulmonary resuscitation and emergency cardiovascular care [database online]. Dallas: AHA; 2005. Circulation. 2005 Dec 13; 112(24 Suppl): IV-35-IV-46. Available: http://circ.ahajournals.org/cgi/content/full/112/24_suppl/iv- Dose of Electrical Current for Biphasic Defibrillators 3
35?maxtoshow=&HITS=10&hits=10&RESULTFORMAT=&fulltext=%22Biphasic+defibrillati on+%22&searchid=1&firstindex=20&resourcetype=hwcit (accessed 2009 May 1). 7. American Heart Association. Management of symptomatic bradycardia and tachycardia. In: Circulation [database online]. Dallas: AHA; 2005. Circulation. 2005;112:IV-67-IV-77. Available: http://circ.ahajournals.org/cgi/reprint/112/24_suppl/iv-67 (accessed 2009 May 4). 8. New Zealand Guidelines Group (NZGG). The management of people with atrial fibrillation and flutter. In: Guidelines and reports [database online]. Wellington: NZGG; 2005. The management of people with atrial fibrillation and flutter. Available: http://www.nzgg.org.nz/guidelines/0085/af_full_guide_(final).pdf (accessed 2009 May 4). Summary with regulatory warning available: http://www.guideline.gov/summary/summary.aspx?doc_id=7351&nbr=004349&string=biph asic (accessed 2009 May). PREPARED BY: Lesley Dunfield, PhD, Manager HTIS Raymond Banks, MLS, Information Specialist Health Technology Inquiry Service Email: htis@cadth.ca Tel: 1-866-898-8439 Dose of Electrical Current for Biphasic Defibrillators 4
APPENDIX FURTHER INFORMATION: Additional references 9. Rull G. Defibrillation and Cardioversion. In: Patient UK [database online]. Leeds: Egton Medical Information Systems (EMIS); 2007. Available: http://emedicine.medscape.com/article/161176-overview (accessed 2009 May 1). 10. Chauhan VV, Quattromani A. Synchronized electrical cardioversion. In: emedicine [database online]. New York: Medscape; 2006. Available: http://emedicine.medscape.com/article/161176-overview (accessed 2009 May 1). Dose of Electrical Current for Biphasic Defibrillators 5