Shunt first: One way to do it
2014; Elsevier BV; Volume: 149; Issue: 2 Linguagem: Inglês
10.1016/j.jtcvs.2014.11.026
ISSN1097-685X
Autores Tópico(s)Tracheal and airway disorders
ResumoSee related article on pages 515-20. See related article on pages 515-20. The management of children with ventricular septal defect, pulmonary valve atresia, diminutive central pulmonary arteries, and multiple aorto-pulmonary collateral arteries is complex, because of the wide variability in pulmonary blood flow. Nowhere is the cliché that “every patient is unique” more apt than with this condition. In addition to the intrinsic anatomic variability that bedevils surgeons caring for such patients, recommendations are widely divergent for optimal provision of pulmonary blood supply. As to whether amalgamation of multiple aorto-pulmonary collateral arteries with native pulmonary arteries (unifocalization) should be performed if native pulmonary arteries are present, a reader of the Journal will have learned, in 2005, that unifocalization “brings no long-term benefits,”1d'Udekem Y. Alphonso N. Nørgaard M.A. Cochrane A.D. Grigg L.E. Wilkinson J.L. et al.Pulmonary atresia with ventricular septal defects and major aortopulmonary collateral arteries: unifocalization brings no long-term benefits.J Thorac Cardiovasc Surg. 2005; 130: 1496-1502Abstract Full Text Full Text PDF PubMed Scopus (91) Google Scholar only to discover a few years later that “unifocalization . . . is essential to achieve excellent outcomes.”2Davies B. Mussa S. Davies P. Stickley J. Jones T.J. Barron D.J. et al.Unifocalization of major aortopulmonary collateral arteries in pulmonary atresia with ventricular septal defect is essential to achieve excellent outcomes irrespective of native pulmonary artery morphology.J Thorac Cardiovasc Surg. 2009; 138: 1269-1275Abstract Full Text Full Text PDF PubMed Scopus (77) Google Scholar A possible advantage of employing unifocalization is the potential to achieve a single-stage complete repair.3Reddy V.M. Liddicoat J.R. Hanley F.L. Midline one-stage complete unifocalization and repair of pulmonary atresia with ventricular septal defect and major aortopulmonary collaterals.J Thorac Cardiovasc Surg. 1995; 109 (discussion 844-5): 832-844Abstract Full Text Full Text PDF PubMed Scopus (183) Google Scholar, 4Lofland G.K. The management of pulmonary atresia, ventricular septal defect, and multiple aorta pulmonary collateral arteries by definitive single stage repair in early infancy.Eur J Cardiothorac Surg. 2000; 18: 480-486Crossref PubMed Scopus (44) Google Scholar By contrast, a multistage approach is obviously necessary if preliminary “rehabilitation” of the native pulmonary arteries is favored, either by direct association of the right ventricle to the main pulmonary artery,5Metras D. Chetaille P. Kreitmann B. Fraisse A. Ghez O. Riberi A. Pulmonary atresia with ventricular septal defect, extremely hypoplastic pulmonary arteries, major aorto-pulmonary collaterals.Eur J Cardiothorac Surg. 2001; 20 (discussion 596-7): 590-596Crossref PubMed Scopus (46) Google Scholar or by creation of a central shunt. The central shunt may be accomplished by direct anastomosis,6Watterson K.G. Wilkinson J.L. Karl T.R. Mee R.B. Very small pulmonary arteries: central end-to-side shunt.Ann Thorac Surg. 1991; 52: 1132-1137Abstract Full Text PDF PubMed Scopus (56) Google Scholar although this technique has typically been accomplished more recently by a polytetrafluoroethylene interposition graft.1d'Udekem Y. Alphonso N. Nørgaard M.A. Cochrane A.D. Grigg L.E. Wilkinson J.L. et al.Pulmonary atresia with ventricular septal defects and major aortopulmonary collateral arteries: unifocalization brings no long-term benefits.J Thorac Cardiovasc Surg. 2005; 130: 1496-1502Abstract Full Text Full Text PDF PubMed Scopus (91) Google Scholar In the present report by Kim and colleagues,7Kim H. Sung S.C. Choi K.H. Lee H.D. Ban G.H. Chang Y.H. The role of a central shunt using an expanded polytetrafluoroethylene tube graft for rehabilitation of diminutive pulmonary arteries in patients with pulmonary atresia with ventricular septal defect and major aortopulmonary collaterals.J Thorac Cardiovasc Surg. 2015; 149: 515-520Abstract Full Text Full Text PDF Scopus (18) Google Scholar the authors have forsworn the potential efficiency of a single-stage approach for a strategy of maximizing the growth of the native pulmonary arteries by use of an initial central shunt. The shunts from aorta to the native main pulmonary artery were constructed in 1 of 2 forms, depending on the size of the main pulmonary artery. The resultant configurations are demonstrated by the superb figures in the article. The outcomes in this report are indeed excellent, with the vast majority of patients (13 of 15) achieving complete repair. No operative deaths occurred at any stage, although 2 patients died in late follow-up. Although these are outstanding results, this approach is very resource intensive. The mean hospital stay after the central shunt procedure was nearly 6 weeks, which seems long for a group whose surgery did not require cardiopulmonary bypass. Furthermore, a large number of operations, 3.8 per patient, were necessary to achieve complete repair, which was not accomplished until 24 months after the initial shunt. Stated another way, these data (3.8 operations in 24 months) suggest that the typical patient faces cardiovascular surgery every 6 months, presumably with multiple, interspersed, cardiac catheterizations and computed tomography angiograms. The aggregate financial costs of this strategy, not to mention the aggregate dosages of anesthetic medication and ionizing radiation, each with potential significant attendant risk, are obviously substantial. Although unifocalization was not initially planned for any of the patients in the present series, it was ultimately necessary for a number of them, as demonstrated in the flow diagram outlining the details of operative staging. In addition, as is obvious from that diagram, 4 patients required a second systemic-to-pulmonary shunt before complete repair. Thus, the touted advantage of the “symmetrical distribution of pulmonary blood flow through the MPA [main pulmonary artery] using a central shunt” was achieved in only 73% of patients. This result is remarkably similar to the experience reported by Liava'a and colleagues,8Liava'a M. Brizard C.P. Konstantinov I.E. Robertson T. Cheung M.M. Weintraub R. et al.Pulmonary atresia, ventricular septal defect, and major aortopulmonary collaterals: neonatal pulmonary artery rehabilitation without unifocalization.Ann Thorac Surg. 2012; 93: 185-191Abstract Full Text Full Text PDF PubMed Scopus (62) Google Scholar wherein a second shunt was necessary in 4 of 20 patients whose initial procedure was a systemic-to-pulmonary shunt. An alternative way to enhance native pulmonary artery growth is to initially associate the main pulmonary artery to the right ventricle, as advocated by Metras and colleagues.5Metras D. Chetaille P. Kreitmann B. Fraisse A. Ghez O. Riberi A. Pulmonary atresia with ventricular septal defect, extremely hypoplastic pulmonary arteries, major aorto-pulmonary collaterals.Eur J Cardiothorac Surg. 2001; 20 (discussion 596-7): 590-596Crossref PubMed Scopus (46) Google Scholar At the price of an initial operation requiring cardiopulmonary bypass, this approach permits antegrade catheter intervention, which is not possible using the central shunt approach in the present report. Kim and colleagues7Kim H. Sung S.C. Choi K.H. Lee H.D. Ban G.H. Chang Y.H. The role of a central shunt using an expanded polytetrafluoroethylene tube graft for rehabilitation of diminutive pulmonary arteries in patients with pulmonary atresia with ventricular septal defect and major aortopulmonary collaterals.J Thorac Cardiovasc Surg. 2015; 149: 515-520Abstract Full Text Full Text PDF Scopus (18) Google Scholar concede this but believe they can simply defer catheter interventions until after placement of a right-ventricle-to-pulmonary-artery conduit. In assessing the merit of the approach advocated in the present report, it is important to define success carefully. If the metric is operative survival, this approach is indeed successful. If the yardstick is the rate of ultimately achieving complete repair with a closed ventricular septal defect, the approach is successful, albeit expensive in procedure number and resource utilization. However, if success is defined as achievement of optimal functional status accompanied by low right ventricular pressure, the jury is still out, as the authors cannot provide us with right ventricular pressure data, as they admirably concede in their discussion of limitations. We, and their patients, eagerly await further reports of ongoing follow-up to answer this crucial question. What can be said is that the approach advocated in this report is safe and effective; whether it is the best approach remains to be seen. A central shunt to rehabilitate diminutive pulmonary arteries in patients with pulmonary atresia with ventricular septal defectThe Journal of Thoracic and Cardiovascular SurgeryVol. 149Issue 2PreviewWe evaluated our clinical experiences on rehabilitation of native pulmonary arteries (PAs) with a central shunt using an expanded polytetrafluoroethylene (ePTFE) tube graft in management of pulmonary atresia with ventricular septal defect (VSD) and major aortopulmonary collateral arteries (MAPCAs) with diminutive PAs. Full-Text PDF Open Archive
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