well with the affected side. The accuracy of this predictive model will further undergo testing in our future Nuss removals. We agree with previous authors [6, 10] on that mechanical compression is the primary element that might explain the mechanism of IMA distortion. This compression possibly correlates with severity of the deformity. In 2 patients of the present series, both IMAs were unaffected despite an asymmetrical character of PE. This can be partially explained by the low placement of the bar, since the IMAs bifurcate after the fifth or sixth ICS and their diameters decrease. The harvested IMAs for coronary artery bypass grafting (CABG) are usually ligated at this point. Residing on this, some have suggested that Nuss bar placement lower than the fourth ICS should not endanger IMA usability by retaining sufficient IMA length. Moreover, these 2 patients have the lowest Haller index of the whole group (3.11 and 3.01). These 2 patients also showed the smallest change in the Haller index after removal of the bars (0.61 and 0.91, respectively). It is possible that a greater degree of change will imply a greater distortion or pressure caused by the bar increasing the risk of IMA obstruction. However, further investigation with a larger number of patients is needed to confirm these observations. It is, therefore, recommended that all patients undergoing CABG following the Nuss procedure undergo preoperative evaluation of IMA patency. According to our results, it is difficult to correlate the risk of IMA distortion and the interval between application and removal of the bar. This is because of the small number of patients and the relatively narrow range of implantation period (31–44 months). In addition, all the post-removal CTAs were performed before discharge of the patients (on approximately postoperative day 5). For this reason, a follow-up CTA 1 year after bar removal is planned and will be addressed in the following report. There has been a shift from digital substration angiography (DSA) towards multidetector CTA in the evaluation of vascular structures, like the IMAs [17]. The high invasive nature of DSA and the significantly improved CTA technology justifies this change. Structures with very small diameters are easily depicted and already used as prognostic values in risk stratification of CABG patients [18–20]. Even with a high coronary calcium burden, a known factor that can adversely affect image quality, CTA can exclude significant coronary artery disease [19]. Being a rapid imaging modality with accurate visualization of vessel anatomy, flow and patency, we used CTA as a reliable and non-invasive method in order to assess the IMAs [6, 19–21]. In conclusion, our preliminary data demonstrate that there is a unilateral obstruction or highly decreased flow pattern of the IMAs in 67% of the patients and the affected side corresponds well with our predictive model. Based on these results, we will extend our pilot for the next pending Nuss bar removals. Follow-up CTA will be performed for all patients 1 year after removal of the bar. Our Radiology department advised the use of MRI in future removals in order to limit the radiation exposure in this young population. We will also analyse the benefit of flow measurement. Conflict of interest: none declared.
REFERENCES [1] Jaroszewski D, Notrica D, McMahon L, Steidley DE, Deschamps C. Current management of pectus excavatum: a review and update of therapy and treatment recommendations. J Am Board Fam Med 2010;23:230–39. [2] Maagaard M, Tang M, Ringgaard S, Nielsen HH, Frøkiær J, Haubuf M et al. Normalized cardiopulmonary exercise function in patients with
[3]
[4]
[5]
[6]
[7]
[8]
[9] [10]
[11]
[12]
[13]
[14] [15] [16] [17]
[18]
[19]
[20]
[21]
9
pectus excavatum three years after operation. Ann Thorac Surg 2013;96: 272–78. Fallon SC, Slater BJ, Nuchtern JG, Cass DL, Kim ES, Lopez ME et al. Complications related to the Nuss procedure: minimizing risk with operative technique. J Pediatr Surg 2013;48:1044–48. Nasr A, Fecteau A, Wales PW. Comparison of the Nuss and the Ravitch procedure for pectus excavatum repair: a meta-analysis. J Pediatr Surg 2010;45:880–6. Nuss D, Kelly RE Jr, Croitoru DP, Katz ME. A 10-year review of a minimally invasive technique for the correction of pectus excavatum. J Pediatr Surg 1998;33:545–52. Yüksel M, Özalper MH, Bostanci K, Ermerak NO, Cimşit Ç, Tasali N et al. Do Nuss bars compromise the blood flow of the internal mammary arteries? Interact CardioVasc Thorac Surg 2013;17:571–75. Adam LA, Meehan JJ. Erosion of the Nuss bar into the internal mammary artery 4 months after minimally invasive repair of pectus excavatum. J Pediatr Surg 2008;43:394–7. Haller JA, Kramer SS, Lietman A. Use of CT scans in selection of patients for pectus excavatum surgery: a preliminary report. J Pediatr Surg 1987;22: 904–6. Liu W, Kong D, Yu F, Yin B. A simple technique for pectus bar removal using a modified Nuss procedure. J Pediatr Surg 2012;48:1137–41. Kelly RE, Goretsky MJ, Obermeyer R, Kuhn MA, Redlinger R, Haney TS et al. Twenty-one years of experience with minimally invasive repair of pectus excavatum by the Nuss procedure in 1215 patients. Ann Surg 2010; 252:1072–81. Vegunta RK, Pacheco PE, Wallace LJ, Pearl RH. Complications associated with the Nuss procedure: continued evolution of the learning curve. Am J Surg 2008;195:313–7. Park HJ, Lee SY, Lee CS. Complications associated with the Nuss procedure: analysis of risk factors and suggested measures for prevention of complications. J Pediatr Surg 2004;39:391–5. Gips H, Zaitsev K, Hiss J. Cardiac perforation by a pectus bar after surgical correction of pectus excavatum: case report and review of the literature. Pediatr Surg Int 2008;24:617–20. Lin CW, Chen KC, Diau GY, Chu CC. Late-onset vital complication after the Nuss procedure for pectus excavatum. Pediatr Surg Int 2012;28:71–3. Leonhardt J, Kübler JF, Feiter J, Ure BM, Petersen C. Complications of the minimally invasive repair of pectus excavatum. J Pediatr Surg 2005;40:e7–9. Hoel TN, Rein KA, Svennevig JL. A life-threatening complication of the Nuss procedure for pectus excavatum. Ann Thorac Surg 2006;81:370–2. Karaman B, Battal B, Bozkurt Y, Bozlar U, Demirkol S, Sahin MA et al. The anatomic evaluation of the internal mammary artery using multidetector CT angiography. Diagn Intern Radiol 2012;18:215–20. Chow BJ, Ahmed O, Small G, Alghamdi AA, Yam Y, Chen L et al. Prognostic value of CT angiography in coronary bypass patients. JACC Cardiovasc Imaging 2011;4:496–502. Otton JM, Yu CY, McCrohon J, Sammel N, Feneley M. Accuracy and clinical outcoumes of computed tomography coronary angiography in the presence of a high coronary calcium score. Heart Lung Circ 2013;22:980–6. Zacho M, Damgaard S, Lilleoer NT, Kelbaek H, Steinbrüchel D, Nielsen MB et al. Long-term internal thoracic artery bypass graft patency and geometry assessed by multidetector computed tomography. Int J Cardiovasc Imaging 2012;28:1577–83. Rosen BD, Litwin SE. The expanding role of computed tomography in the assessment of coronary artery disease and cardiac anatomy. Trends Cardiovasc Med 2011;21:193–9.
eComment. Suggestions that may prevent internal mammary artery obstruction after thoracoscopic Nuss bar repair of pectus Author: Sameh I Sersar Cardiothoracic Surgery, Mansoura University and KAMC, Makkah, Saudi Arabia doi: 10.1093/icvts/ivu136 © The Author 2014. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved. I read with great interest the initial report by Külcü et al. about the patency of the internal mammary arteries (IMA) after removal of the Nuss bar [1]. I have a few comments. Firstly, was the interference with IMA patency associated with any clinical, biochemical or radiological evidence of myocardial ischaemia? Secondly, IMA patency compromise could be due not only to the compressive force of the bar, but also to the relative shortening of the IMA after correction of the pectus excavatum, thus stretching the IMA.
WORK IN PROGRESS REPORT
K. Külcü et al. / Interactive CardioVascular and Thoracic Surgery
10
K. Külcü et al. / Interactive CardioVascular and Thoracic Surgery
Whatever the mechanism, I can suggest some things which may help to overcome this high percentage of unilateral total obstruction or highly decreased flow pattern (67%). My two suggestions are, firstly, that I found it useful to harvest the IMA 1 cm proximal and distal to the site of implantation of the Nuss bar, passing the bar between the sternum and the harvested piece of the IMA in view of the uncertainty about the future clinical impact of this IMA and iatrogenic obstruction. Thoracoscopic IMA harvesting from a single side is safe and reproducible and satisfactory length of both arteries can be obtained [2]. Secondly, it may be that a retrospective study of the cases who had Nuss repair could help to determine whether those patients had more significant myocardial ischaemic events or not. Conflict of interest: none declared. References [1] Külcü K, Elenbaas TW, Nguyen DT, Verhees RP, Mihl C, Verberkmoes NY et al. Patency of the internal mammary arteries after removal of the Nuss bar: an initial report. Interact CardioVasc Thorac Surg 2014;19:6–10. [2] Vassiliades TAJr. A unilateral approach to bilateral thoracoscopic internal mammary artery harvesting. Interact CardioVasc Thorac Surg 2003;2:87–90.
eComment. Nuss pectus excavatum repair: a hurdle for the treatment of coronary disease Authors: Alain Wurtz, Ilir Hysi, Lotfi Benhamed, and Andre Vincentelli Clinic of Cardiac and Thoracic Surgery, Lille University Teaching Hospital, CHULille, Lille, France doi: 10.1093/icvts/ivu150 © The Author 2014. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved. We read with great interest the comments by Sameh I Sersar [1] on the recent article from Külcü and colleagues [2]. In 2013, Yüksel and colleagues reported a prospective study of the internal thoracic artery (ITA) blood flow after placement of a
Nuss bar for the treatment of pectus excavatum, and clearly demonstrated that the blood flow of these arteries was affected in 44% of patients in the postoperative period [3]. However, the future of these anomalies was unknown. Külcü and colleagues reporting partial or total obstruction of the ITA in 67% of their patients after Nuss bar removal, provide a preliminary answer to the question [2]. These findings raise concern, since ITAs are widely used for coronary bypass grafting. Therefore, with a view to protect the ITA from compression/interruption for future potential use, Sersar suggests performing mobilization under thoracoscopic guidance at the level of the site of implantation of the Nuss bar and passing the bar between the undersurface of the thoracic wall and the mobilized ITA segment [1]. In fact, such Nuss bar placement might lead to adhesions to the surrounding structures, and consecutive ITA lesions at the time of the bar removal. These adhesions have already been described as the cause of severe or lethal cardiac haemorrhages [4]. Finally, we consider that the best prevention of such outcomes is correcting pectus excavatum by means of a less invasive simplified Ravitch-type technique [5]. Conflict of interest: none declared. References [1] Sersar SI. Suggestions that may prevent internal mammary artery obstruction after thoracoscopic Nuss bar repair of pectus. Interact CardioVasc Thorac Surg 2014;19:9–10. [2] Külcü K, Elenbaas TW, Nguyen DT, Verhees RP, Mihl C, Verberkmoes NY et al. Patency of the internal mammary arteries after removal of the Nuss bar: an initial report. Interact CardioVasc Thorac Surg 2014;19:6–10. [3] Yüksel M, Ozalper MH, Bostanci K, Ermerak NO, Cimsit C, Tasali N et al. Do Nuss bars compromise the blood flow of the internal mammary arteries? Interact CardioVasc Thorac Surg 2013;17:571–5. [4] Haecker FM, Berberich T, Mayr J, Gambazzi F. Near-fatal bleeding after transmyocardial ventricle lesion during removal of the pectus bar after the Nuss procedure. J Thorac Cardiovasc Surg 2009;138:1240–1. [5] Wurtz A, Rousse N, Benhamed L, Conti M, Hysi I, Pinçon C et al. Simplified open repair for anterior chest wall deformities. Analysis of results in 205 patients. Orthop Traumatol Surg Res 2012;98:319–26.
REFERENCES [1] Jaroszewski D, Notrica D, McMahon L, Steidley DE, Deschamps C. Current management of pectus excavatum: a review and update of therapy and treatment recommendations. J Am Board Fam Med 2010;23:230–39. [2] Maagaard M, Tang M, Ringgaard S, Nielsen HH, Frøkiær J, Haubuf M et al. Normalized cardiopulmonary exercise function in patients with
[3]
[4]
[5]
[6]
[7]
[8]
[9] [10]
[11]
[12]
[13]
[14] [15] [16] [17]
[18]
[19]
[20]
[21]
9
pectus excavatum three years after operation. Ann Thorac Surg 2013;96: 272–78. Fallon SC, Slater BJ, Nuchtern JG, Cass DL, Kim ES, Lopez ME et al. Complications related to the Nuss procedure: minimizing risk with operative technique. J Pediatr Surg 2013;48:1044–48. Nasr A, Fecteau A, Wales PW. Comparison of the Nuss and the Ravitch procedure for pectus excavatum repair: a meta-analysis. J Pediatr Surg 2010;45:880–6. Nuss D, Kelly RE Jr, Croitoru DP, Katz ME. A 10-year review of a minimally invasive technique for the correction of pectus excavatum. J Pediatr Surg 1998;33:545–52. Yüksel M, Özalper MH, Bostanci K, Ermerak NO, Cimşit Ç, Tasali N et al. Do Nuss bars compromise the blood flow of the internal mammary arteries? Interact CardioVasc Thorac Surg 2013;17:571–75. Adam LA, Meehan JJ. Erosion of the Nuss bar into the internal mammary artery 4 months after minimally invasive repair of pectus excavatum. J Pediatr Surg 2008;43:394–7. Haller JA, Kramer SS, Lietman A. Use of CT scans in selection of patients for pectus excavatum surgery: a preliminary report. J Pediatr Surg 1987;22: 904–6. Liu W, Kong D, Yu F, Yin B. A simple technique for pectus bar removal using a modified Nuss procedure. J Pediatr Surg 2012;48:1137–41. Kelly RE, Goretsky MJ, Obermeyer R, Kuhn MA, Redlinger R, Haney TS et al. Twenty-one years of experience with minimally invasive repair of pectus excavatum by the Nuss procedure in 1215 patients. Ann Surg 2010; 252:1072–81. Vegunta RK, Pacheco PE, Wallace LJ, Pearl RH. Complications associated with the Nuss procedure: continued evolution of the learning curve. Am J Surg 2008;195:313–7. Park HJ, Lee SY, Lee CS. Complications associated with the Nuss procedure: analysis of risk factors and suggested measures for prevention of complications. J Pediatr Surg 2004;39:391–5. Gips H, Zaitsev K, Hiss J. Cardiac perforation by a pectus bar after surgical correction of pectus excavatum: case report and review of the literature. Pediatr Surg Int 2008;24:617–20. Lin CW, Chen KC, Diau GY, Chu CC. Late-onset vital complication after the Nuss procedure for pectus excavatum. Pediatr Surg Int 2012;28:71–3. Leonhardt J, Kübler JF, Feiter J, Ure BM, Petersen C. Complications of the minimally invasive repair of pectus excavatum. J Pediatr Surg 2005;40:e7–9. Hoel TN, Rein KA, Svennevig JL. A life-threatening complication of the Nuss procedure for pectus excavatum. Ann Thorac Surg 2006;81:370–2. Karaman B, Battal B, Bozkurt Y, Bozlar U, Demirkol S, Sahin MA et al. The anatomic evaluation of the internal mammary artery using multidetector CT angiography. Diagn Intern Radiol 2012;18:215–20. Chow BJ, Ahmed O, Small G, Alghamdi AA, Yam Y, Chen L et al. Prognostic value of CT angiography in coronary bypass patients. JACC Cardiovasc Imaging 2011;4:496–502. Otton JM, Yu CY, McCrohon J, Sammel N, Feneley M. Accuracy and clinical outcoumes of computed tomography coronary angiography in the presence of a high coronary calcium score. Heart Lung Circ 2013;22:980–6. Zacho M, Damgaard S, Lilleoer NT, Kelbaek H, Steinbrüchel D, Nielsen MB et al. Long-term internal thoracic artery bypass graft patency and geometry assessed by multidetector computed tomography. Int J Cardiovasc Imaging 2012;28:1577–83. Rosen BD, Litwin SE. The expanding role of computed tomography in the assessment of coronary artery disease and cardiac anatomy. Trends Cardiovasc Med 2011;21:193–9.
eComment. Suggestions that may prevent internal mammary artery obstruction after thoracoscopic Nuss bar repair of pectus Author: Sameh I Sersar Cardiothoracic Surgery, Mansoura University and KAMC, Makkah, Saudi Arabia doi: 10.1093/icvts/ivu136 © The Author 2014. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved. I read with great interest the initial report by Külcü et al. about the patency of the internal mammary arteries (IMA) after removal of the Nuss bar [1]. I have a few comments. Firstly, was the interference with IMA patency associated with any clinical, biochemical or radiological evidence of myocardial ischaemia? Secondly, IMA patency compromise could be due not only to the compressive force of the bar, but also to the relative shortening of the IMA after correction of the pectus excavatum, thus stretching the IMA.
WORK IN PROGRESS REPORT
K. Külcü et al. / Interactive CardioVascular and Thoracic Surgery
10
K. Külcü et al. / Interactive CardioVascular and Thoracic Surgery
Whatever the mechanism, I can suggest some things which may help to overcome this high percentage of unilateral total obstruction or highly decreased flow pattern (67%). My two suggestions are, firstly, that I found it useful to harvest the IMA 1 cm proximal and distal to the site of implantation of the Nuss bar, passing the bar between the sternum and the harvested piece of the IMA in view of the uncertainty about the future clinical impact of this IMA and iatrogenic obstruction. Thoracoscopic IMA harvesting from a single side is safe and reproducible and satisfactory length of both arteries can be obtained [2]. Secondly, it may be that a retrospective study of the cases who had Nuss repair could help to determine whether those patients had more significant myocardial ischaemic events or not. Conflict of interest: none declared. References [1] Külcü K, Elenbaas TW, Nguyen DT, Verhees RP, Mihl C, Verberkmoes NY et al. Patency of the internal mammary arteries after removal of the Nuss bar: an initial report. Interact CardioVasc Thorac Surg 2014;19:6–10. [2] Vassiliades TAJr. A unilateral approach to bilateral thoracoscopic internal mammary artery harvesting. Interact CardioVasc Thorac Surg 2003;2:87–90.
eComment. Nuss pectus excavatum repair: a hurdle for the treatment of coronary disease Authors: Alain Wurtz, Ilir Hysi, Lotfi Benhamed, and Andre Vincentelli Clinic of Cardiac and Thoracic Surgery, Lille University Teaching Hospital, CHULille, Lille, France doi: 10.1093/icvts/ivu150 © The Author 2014. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved. We read with great interest the comments by Sameh I Sersar [1] on the recent article from Külcü and colleagues [2]. In 2013, Yüksel and colleagues reported a prospective study of the internal thoracic artery (ITA) blood flow after placement of a
Nuss bar for the treatment of pectus excavatum, and clearly demonstrated that the blood flow of these arteries was affected in 44% of patients in the postoperative period [3]. However, the future of these anomalies was unknown. Külcü and colleagues reporting partial or total obstruction of the ITA in 67% of their patients after Nuss bar removal, provide a preliminary answer to the question [2]. These findings raise concern, since ITAs are widely used for coronary bypass grafting. Therefore, with a view to protect the ITA from compression/interruption for future potential use, Sersar suggests performing mobilization under thoracoscopic guidance at the level of the site of implantation of the Nuss bar and passing the bar between the undersurface of the thoracic wall and the mobilized ITA segment [1]. In fact, such Nuss bar placement might lead to adhesions to the surrounding structures, and consecutive ITA lesions at the time of the bar removal. These adhesions have already been described as the cause of severe or lethal cardiac haemorrhages [4]. Finally, we consider that the best prevention of such outcomes is correcting pectus excavatum by means of a less invasive simplified Ravitch-type technique [5]. Conflict of interest: none declared. References [1] Sersar SI. Suggestions that may prevent internal mammary artery obstruction after thoracoscopic Nuss bar repair of pectus. Interact CardioVasc Thorac Surg 2014;19:9–10. [2] Külcü K, Elenbaas TW, Nguyen DT, Verhees RP, Mihl C, Verberkmoes NY et al. Patency of the internal mammary arteries after removal of the Nuss bar: an initial report. Interact CardioVasc Thorac Surg 2014;19:6–10. [3] Yüksel M, Ozalper MH, Bostanci K, Ermerak NO, Cimsit C, Tasali N et al. Do Nuss bars compromise the blood flow of the internal mammary arteries? Interact CardioVasc Thorac Surg 2013;17:571–5. [4] Haecker FM, Berberich T, Mayr J, Gambazzi F. Near-fatal bleeding after transmyocardial ventricle lesion during removal of the pectus bar after the Nuss procedure. J Thorac Cardiovasc Surg 2009;138:1240–1. [5] Wurtz A, Rousse N, Benhamed L, Conti M, Hysi I, Pinçon C et al. Simplified open repair for anterior chest wall deformities. Analysis of results in 205 patients. Orthop Traumatol Surg Res 2012;98:319–26.
