ABC | Volume 112, Nº2, February 2019

Original Article Fernandes et al Conversion to total cavopulmonary connection Arq Bras Cardiol. 2019; 112(2):130-135 rate of resolution of these arrhythmias (only 57% of cases indicated by arrhythmia). In cases in which surgical cryoablation was performed (three cases), the outcomes were not favorable: one case evolved to death in the recent postoperative period (due to bleeding and coagulopathy), one arrhythmia was not resolved, and one case progressed with total atrioventricular block, needing definitive pacemaker implantation. This patient evolved with dysfunctions and is currently in line for cardiac transplantation due to significant worsening of functional class and ventricular function. Although most studies suggest a benefit performing cryoablation, 24,26-31 our findings suggest that surgical cryoablation should not be performed routinely in conversion to TCPC surgery, despite our small sample size. Studies fromSouth Korea and Japan 32,33 have reported security and improvement in clinical outcomes by implanting permanent pacemaker in Fontan conversion. However, our only case with pacemaker implantation had unfavorable outcome, and is now in line for heart transplantation. Takeuchi et al. 34 showed favorable outcomes combining FCwith resynchronization, but none of our patients were elected for resynchronization. The presence of ventricular dysfunction before the FC procedure was found in five cases. All cases were elected to conversion by arrhythmia, one of them died and all the survivors had improved ventricular functions. Therefore, we conclude that the procedure presented a satisfactory result in improving the ventricular function. However, we observed no improvement of the arrhythmia in two cases of the survivors who presented preoperative dysfunction. There was a significant improvement in functional class and quality of life of these patients after conversion, and therefore, our results demonstrate the importance and necessity of converting selected cases. These findings motivated us to perform this surgery in more cases after our first two cases that evolved to death. Currently, we have only a few cases of FK alive being followed in our ambulatory. A review by Brida et al. 35 analyzed 1182 patients from 37 studies and concluded that conversion had substantial mortality risk. However, the results vary between centers and lower early mortality was associated with earlier age and with treatment being performed at high experienced centers. Conclusions The conversion of atrial-pulmonary anastomosis (Fontan- Kreutezer) to TCPC is a complex procedure with high mortality and morbidity justifying a prolonged hospitalization time, so this surgery needs to be performed in experienced tertiary hospitals. The conversion of atrial-pulmonary anastomosis to TCPC has, in our experience, improved the functional class and consequently the patients' quality of life despite an unsatisfactory resolution of the arrhythmia. Author contributions Conception and design of the research: Fernandes GC, Silva GVR, Caneo LF; acquisition of data: Fernandes GC, Silva GVR, Caneo LF, Tanamati C, Turquetto AL; analysis and interpretation of the data and critical revision of the manuscript for intellectual contente: Fernandes GC, Silva GVR, Caneo LF, Tanamati C, Turquetto AL, Jatene MB; statistical analysis: Fernandes GC, Caneo LF, TurquettoAL; writing of themanuscript: Fernandes GC, Silva GVR, Caneo LF, Turquetto AL, Jatene MB. Potential Conflict of Interest No potential conflict of interest relevant to this article was reported. Sources of Funding There were no external funding sources for this study. Study Association This study is not associatedwith any thesis or dissertationwork. Ethics approval and consent to participate This article does not contain any studies with human participants or animals performed by any of the authors. 1. Caneo LF, Neirotti RA, Turquetto ALR, Jatene MB: A operação de Fontan não é o destino final. Arq Bras Cardiol. 2016;106(2):162-5. 2. Caneo LF, Turquetto ALR, Neirotti RA, Binotto MA, Miana LA, Tanamati C, et al. Lessons Learned Froma Critical Analysis of the FontanOperationOver ThreeDecades inaSingle Institution.World JPediatrCongHeartSurg.2017; 8(3):376–84. 3. Fontan F, Baudet E: Surgical repair of tricuspid atresia. Thorax. 1971;26(3):240-8. 4. KreutzerJ,KeaneF,LockJE,WalshEP,JonasRA,CastanedaAR,etaI.Conversion of modified Fontan procedure to lateral atrial tunnel cavopulmonary anastomosis. J Thorac Cardiovasc Surg. 1996;111(6):1169-76. 5. Kreutzer C, Kreutzer J, Kreutzer GO: Five decades of the Fontan Kreutzer procedure. Front Pediatr. 2013 Dec 18;1:45. 6. 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