title: Cardioscopic Trans-septal Cryoablation of Left Atrium in Nonmitral Cases.
abstract: BACKGROUND
  : A modified maze procedure in which trans-septal cardioscopy was used for cryoablation in the left atrium is described.
  
  
  METHODS
  : The technique was used in 11 consecutive patients (9 men and 2 women, 56.5 ± 19.8 years) with permanent atrial fibrillation (Af) and concomitant nonmitral cardiac or aortic disease: aortic valvular disease in 4 patients, atrial septal defect (ASD) in 2 patients, tricuspid regurgitation in 2 patients, acute aortic dissection in 1 patient, arch aneurysm in 1 patient, and coronary artery disease in 1 patient. The mean Af duration detected in 7 cases was 18.5 ± 10.1 months. Partial sternotomy was used in aortic valve replacement, ASD closure, and tricuspid valve plasty, and fullsternotomy was used in aortic graft replacement and coronary artery bypass. Cardiopulmonary bypass was established, aortic cross-clamp was performed, a right atriotomy was created, a cryoablation probe and cardioscope (3 mm) were introduced into the left atrium through a 1-cm cut at the fossa ovalis or ASD, and cardioscopic left-atrial endocardial cryoablation was performed. The right-side maze procedure was conducted directly. The atrial appendages were excised in each case.
  
  
  RESULTS
  : Left-atrial cardioscopic cryoablation required 25.0 ± 5.5 minutes, and no deaths or procedure-related morbidities occurred. The mean follow-up period was 12 ± 8.5 months. One patient with tricuspid regurgitation died of liver failure. With the exception of coronary and acute dissection cases, all patients have maintained a sinus rhythm.
  
  
  CONCLUSIONS
  : Although experience is limited, videocardioscopic trans-septal left-atrial cryoablation is a viable method for nonmitral Af cases, and the partial sternotomy approach can be performed.
authors.affiliation: From the Department of Cardiovascular Surgery, Tokyo Metropolitan Fuchu General Hospital, Tokyo, Japan.
authors.forename: Toshiya
authors.initials: T
authors.lastname: Ohtsuka
authors.forename: Mikio
authors.initials: M
authors.lastname: Ninomiya
authors.forename: Taisei
authors.initials: T
authors.lastname: Maemura