title: Ablation of atrial fibrillation with the Epicor system: a prospective observational trial to evaluate safety and efficacy and predictors of success.
abstract: BACKGROUND
  High intensity focused ultrasound (HIFU) energy has evolved as a new surgical tool to treat atrial fibrillation (AF). We evaluated safety and efficacy of AF ablation with HIFU and analyzed predictors of success in a prospective clinical study.
  
  
  METHODS
  From January 2007 to June 2008, 110 patients with AF and concomitant open heart surgery were enrolled into the study. Main underlying heart diseases were aortic valve disease (50%), ischemic heart disease (48%), and mitral valve disease (18%). AF was paroxysmal in 29%, persistent in 31%, and long standing persistent in 40% of patients, lasting for 1 to 240 months (mean 24 months). Mean left atrial diameter was 50 +/- 7 mm. Each patient underwent left atrial ablation with the Epicor system prior to open heart surgery. After surgery, the patients were treated with amiodarone and coumadin for 6 months. Follow-up studies including resting ECG, 24 h Holter ECG, and echocardiography were obtained at 6 and 12 months.
  
  
  RESULTS
  All patients had successful application of the system on the beating heart prior to initiation of extracorporeal circulation. On average, 11 +/- 1 ultrasound transducer elements were used to create the box lesion. The hand-held probe for additional linear lesions was employed in 83 cases. No device-related deaths occurred. Postoperative pacemaker insertion was necessary in 4 patients. At 6 months, 62% of patients presented with sinus rhythm. No significant changes were noted at 12 months. Type of AF and a left atrial diameter > 50 mm were predictors for failure of AF ablation.
  
  
  CONCLUSIONS
  AF ablation with the Epicor system as a concomitant procedure during open heart surgery is safe and acceptably effective. Our overall conversion rate was lower than in previously published reports, which may be related to the lower proportion of isolated mitral valve disease in our study population. Left atrial size may be useful to determine patients who are most likely to benefit from the procedure.
authors.affiliation: Department of Cardiothoracic Surgery, University Medical Center Regensburg, Germany. simon@schopka.net
authors.forename: Simon
authors.initials: S
authors.lastname: Schopka
authors.forename: Christof
authors.initials: C
authors.lastname: Schmid
authors.forename: Andreas
authors.initials: A
authors.lastname: Keyser
authors.forename: Ariane
authors.initials: A
authors.lastname: Kortner
authors.forename: Julia
authors.initials: J
authors.lastname: Tafelmeier
authors.forename: Claudius
authors.initials: C
authors.lastname: Diez
authors.forename: Leopold
authors.initials: L
authors.lastname: Rupprecht
authors.forename: Michael
authors.initials: M
authors.lastname: Hilker
mesh_terms: D000368:Aged; D001281:Atrial Fibrillation / Q000601:surgery*; D006348:Cardiac Surgical Procedures; D005260:Female; D006331:Heart Diseases / Q000150:complications / Q000601:surgery; D057086:High-Intensity Focused Ultrasound Ablation / Q000379:methods; D006801:Humans; D008297:Male; D011182:Postoperative Care; D016896:Treatment Outcome
references.citation: Ann Thorac Surg. 2006 Oct;82(4):1392-9
references.pmid: 16996940
references.citation: J Thorac Cardiovasc Surg. 2005 Sep;130(3):803-9
references.pmid: 16153932
references.citation: Am J Med. 1995 May;98(5):476-84
references.pmid: 7733127
references.citation: J Thorac Cardiovasc Surg. 2001 Dec;122(6):1239-40
references.pmid: 11726904
references.citation: Eur Heart J. 2005 Sep;26(18):1866-72
references.pmid: 15845559
references.citation: Ann Thorac Surg. 2003 Jul;76(1):276-7
references.pmid: 12842559
references.citation: Ann Thorac Surg. 2008 Oct;86(4):1212-7
references.pmid: 18805163
references.citation: Ann Thorac Surg. 2002 Oct;74(4):1050-6; discussion 1057
references.pmid: 12400744
references.citation: Pacing Clin Electrophysiol. 2008 Aug;31(8):1057-63
references.pmid: 18684264
references.citation: Stroke. 1997 Jun;28(6):1101-6
references.pmid: 9183333
references.citation: Am J Cardiol. 2002 Jun 15;89(12):1381-7
references.pmid: 12062732
references.citation: N Engl J Med. 1998 Sep 3;339(10):659-66
references.pmid: 9725923
references.citation: Circulation. 2008 Sep 30;118(14 Suppl):S78-82
references.pmid: 18824774
references.citation: Ann Thorac Surg. 2004 May;77(5):1514-22; discussion 1522-4
references.pmid: 15111135
references.citation: J Thorac Cardiovasc Surg. 2003 Dec;126(6):1822-8
references.pmid: 14688693
references.citation: N Engl J Med. 2008 Oct 23;359(17):1778-85
references.pmid: 18946063
references.citation: Eur J Cardiothorac Surg. 1997 Jul;12(1):1-19
references.pmid: 9262075
references.citation: Ann Thorac Surg. 2007 Dec;84(6):1978-83
references.pmid: 18036920