Techniques for repair of complete atrioventricular septal

Transcription

1 No Ventricular Septal Defect Patch Atrioventricular Septal Defect Repair Carl L. Backer, MD *, Osama Eltayeb, MD *, Michael C. Mongé, MD *, and John M. Costello, MD For the past 10 years, our center has used the no ventricular septal defect patch atrioventricular septal defect repair proposed independently by Wilcox and Nicholson. The technique emphasizes direct closure of the ventricular element of the defect and a pericardial patch for the atrial component. A particular advantage of the operation is that it lends itself to repair in the smaller infant, which allows operative repair at 3-4 months of age, decreasing the risk of perioperative problems with pulmonary hypertension. The result of this strategy at multiple centers is a very low operative mortality, a low incidence of left atrioventricular valve reoperation, and an extremely low incidence of need for a pacemaker. Operative Techniques in Thoracic and Cardiovasculary Surgery 20: r 2016 Elsevier Inc. All rights reserved. KEYWORDS Atrioventricular septal defect, Zone of apposition, Atrioventricular canal, Surgery Techniques for repair of complete atrioventricular septal defect (AVSD) have evolved substantially over the years. Surgeons at various times have used the classic singlepatch technique, the 2-patch technique, and more recently the modified single-patch or no VSD patch technique. The modified single-patch (no ventricular septal defect [VSD] patch) technique was independently proposed by Wilcox et al 1 and Nicholson et al. 2 This strategy eliminated placement of a patch to close the ventricular element of the defect. Rather, there is direct closure of the ventricular component by sandwiching the top of the ventricular septum, the common AV valve, and a pericardial patch. The patch is then used to close the atrial component of the defect. The initial concerns raised regarding the no VSD patch technique were that there would be residual ventricular level shunting and an increased risk for the development of left ventricular outflow tract obstruction. The reason to adopt the no VSD patch technique primarily revolves around improving the outcome of the repair of the left atrioventricular (AV) valve. This, in many series, has been the Achilles heel of complete AVSD repair. Our program transitioned from sole utilization of the 2- patch technique to essentially complete adoption of the no *Division of Cardiovascular-Thoracic Surgery, Ann & Robert H. Lurie Children s Hospital of Chicago, Chicago, IL Division of Cardiology, Ann & Robert H. Lurie Children s Hospital of Chicago, Chicago, IL Address reprint requests to Dr. Backer, Division of Cardiovascular-Thoracic Surgery, Ann & Robert H. Lurie Children s Hospital of Chicago, 225 E Chicago Ave, mc 22, Chicago, IL cbacker@luriechildrens.org VSD patch or modified single-patch technique over a 5- year period from This was based on our initial experience that the modified single-patch technique was performed with significantly shorter cross-clamp and cardiopulmonary bypass times with comparable results. However, further follow-up has demonstrated that the incidence of reoperation on the left AV valve and incidence of need for pacemaker placement have been less than with the other techniques. 4 Of critical importance our recent evaluation demonstrated that left ventricular outflow tract obstruction does not appear to be a significant postoperative issue with the modified single-patch repair. 5 The following illustrations demonstrate use of the no VSD patch technique for complete AVSD in 2 different patients; 1 with Rastelli type A configuration of the AV valves and the other with Rastelli type C configuration of the AV valves. 6 At Ann & Robert H. Lurie Children s Hospital of Chicago we transitioned from using the 2-patch technique to now using almost exclusively the modified single-patch or no VSD patch technique (Figs. 1-10). This transition began in the year By 2006, we were using the modified singlepatch technique on all patients except for those with an extremely large ventricular component (415 mm). From we performed no VSD patch AVSD closure in 77 patients. During that same time period we only used the 2-patch technique twice. Patient characteristics are shown in Table 1. Results were as follows: there was 1 early mortality for a 2% overall mortality rate. The median postoperative length of stay was 10 days. No patient required a /$-see front matter r 2016 Elsevier Inc. All rights reserved

2 280 Table 1 Patient Characteristics for No VSD Patch AVSD Repair Patients n ¼ 77 Median age 4.2 mo Median weight 5 kg Trisomy (74%) Prior Coarctation repair 8 (10%) pacemaker in the postoperative period. Only 2 patients have required reoperation for left ventricular outflow tract obstruction and both had prior coarctation repair. Coarctation repair appears to be a marker for the need for reoperation for C.L. Backer et al. left ventricular outflow tract obstruction unrelated to the type of AVSD repair. All patients with left ventricular outflow tract obstruction requiring reoperation had Rastelli type A configuration. In all, 3 patients required reoperation on the left AV valve, 1 early and 2 late. Among all, 1 patient required reoperation for a residual VSD. This patient also had a reoperation on the left AV valve. The results of a meta-analysis that we performed comparing the modified single-patch (no VSD patch) to the 2-patch and classic single-patch technique are shown in Table 2. 4 The no VSD patch strategy has a lower operative mortality, lower need for reoperation on the left AV valve, and a lower Table 2 Meta-Analysis of 3 Operations for Atrioventricular Repair No VSD Patch (n ¼ 272) 2-Patch (n ¼ 889) Classic Single-Patch (n ¼ 350) Mortality (%) Left AV Valve, Reoperation (%) Heart block requiring pacemaker (%) Figure 1 The child has been placed on cardiopulmonary bypass with venous cannulae in the superior and inferior vena cava. The aorta has been cross-clamped and cold blood cardioplegia delivered. The dotted line shows the incision to be made for exposure in the right atrium. Note the atrial incision is carried medial to the inferior vena cava, which allows the visualization of the AV valve to be substantially improved. This unhinges the right atrium from the ventricle for excellent exposure of the atrioventricular valve.

3 No VSD patch AVSD repair 281 A AV node Coronary sinus Figure 2 (A) The right atrium has been opened and retracted showing the Rastelli classification type A. Note that the superior bridging leaflet is divided and attached to the crest of the ventricular septum. Inset shows a suture used to mark the approximation of the superior and interior bridging leaflets leading to separate right and left atrioventricular valves. (AV ¼ atrioventricular).

4 282 C.L. Backer et al. B Superior bridging leaflet Figure 2 (Continued) (B) Rastelli classification C. The superior bridging leaflet is not divided and is not attached to the ventricular septum. This has also been referred to as a free-floating leaflet.

5 No VSD patch AVSD repair 283 A Proposed lines of separation of R and L AV valves B Figure 3 (A) demonstrates bulb irrigation of the common atrioventricular valve in Rastelli A. The dotted line indicates where a proposed line of separation of the right and left atrioventricular valves would occur with placement of the sutures. Inset (B) shows bulb insufflation of the common AV valve in a patient with Rastelli type C. (L ¼ left; R ¼ right).

6 284 C.L. Backer et al. Figure 4 A series of pledgetted horizontal mattress sutures have been placed on the right ventricular side of the ventricular septum. They have then been passed through the appropriate site on the common AV valve for a patient with Rastelli type A. The sutures are also shown as they pass through the pericardial patch. A rubber-shod clamp is shown holding a single suture which demonstrates where the superior and inferior bridging leaflets are to be brought together to begin the closure of the zone of apposition.

7 No VSD patch AVSD repair 285 A Figure 5 (A) shows the completed ventricular element closure in a patient with Rastelli type A. The pledget-based sutures have been passed through the ventricular septum, through the AV valve, and have been tied. Note that the sutures are only passed through the left AV valve portion of the superior bridging leaflet at this point. AV ¼ atrioventricular.

8 286 C.L. Backer et al. B Figure 5 (Continued) (B) The anatomy of a patient with Rastelli type C classification. Note that the superior bridging leaflet portion of the right and left AV valves is completed, because of the patient anatomy. AV ¼ atrioventricular.

9 No VSD patch AVSD repair 287 Pericardial patch AV valve RV LV RV Figure 6 Relationship of the pledget to the crest of the ventricular septum, the AVvalve tissue, and the pericardial patch. AV ¼ atrioventricular; LV ¼ left ventricle; RA ¼ right atrium; RV ¼ right ventricle.

10 288 C.L. Backer et al. Zone of apposition Left AV valve Figure 7 The pericardial patch has been reflected anteriorly. We are looking directly down at the left AV valve. The zone of apposition has been closed with multiple interrupted prolene sutures. AV ¼ atrioventricular.

11 No VSD patch AVSD repair 289 A Figure 8 (A) Rastelli A. The superior bridging leaflet of the right AV valve must now be suspended to the pericardial patch. This is illustrated with running prolene suture. In addition the superior and inferior bridging leaflets of the right AV valve have been approximated closing the zone of apposition of the right AV valve. This usually requires only 2 or 3 sutures. AV ¼ atrioventricular.

12 290 C.L. Backer et al. B SBL IBL Coronary sinus AV node ASD Figure 8 (Continued) (B) Rastelli type C. Note that the superior bridging leaflet of the right AV valve has already been attached to the pericardial patch. This illustration shows the sutures being placed to close the zone of apposition of the right AV valve, and the suture used to close the atrial component of the defect. ASD ¼ atrial septal defect; AV ¼ atrioventricular; IBL ¼ inferior bridging leaflet; SBL ¼ superior bridging leaflet.

13 No VSD patch AVSD repair 291 AV node Coronary sinus Figure 9 Rastelli A, the atrial portion of the defect is being closed with a running suture technique using the autologous pericardial patch. Typically, 2 suture lines are created which then join in the middle to complete the closure. Note the AV node position at the apex of the triangle of Koch adjacent to the coronary sinus. The sutures adjacent to the AV node are placed very superficially and are closer to the left AV valve. This is typically a fine prolene suture, either 6.0 or 5.0 prolene. Care is taken not to grasp this area with a pickup or injure this area with any type of instrument such as a cardiotomy sucker. AV ¼ atrioventricular.

14 292 C.L. Backer et al. Left AV valve Right AV valve Figure 10 Completed procedure in a cut-a-way view. The common AV valve has been separated into left and right AV valves. The zone of apposition of both AV valves has been closed. The ventricular element of the defect has been eliminated by the compression of the crest of the ventricular septum to the common AV valve and the autologous pericardial patch. AV ¼ atrioventricular. incidence of heart block needing a pacemaker. The aortic cross-clamp and aortic bypass times are substantially shorter. Also, the modified single-patch technique lends itself to repair in the smaller infant which allows operative repair at a recommended age of 4 months which should decrease the risk of perioperative problems of pulmonary hypertension. The no VSD patch AVSD repair is our current recommended procedure of choice for patients with complete AVSD. References 1. Wilcox BR, Jones DR, Frantz EG, et al: Anatomically sound, simplified approach to repair of complete atrioventricular septal defect. Ann Thorac Surg 64: , Nicholson IA, Nunn GR, Sholler GF, et al: Simplified single-patch technique for the repair of atrioventricular septal defect. J Thorac Cardiovasc Surg 118: , Backer CL, Stewart RD, Bailliard F, et al: Complete atrioventricular canal: Comparison of modified single-patch technique with two-patch technique. Ann Thorac Surg 84: , Backer CL, Stewart RD, Mavroudis C: What is the best technique for repair of complete atrioventricular canal? Semin Thorac Cardiovasc Surg 19: , Backer CL, Eltayeb O, Mongé MC, et al: Modified single patch: are we still worried about subaortic stenosis? Ann Thorac Surg 99: , Rastelli GC, Kirklin JW, Titus JL: Anatomic observations on complete form of persistent common atrioventricular canal with special reference to atrioventricular valves. Mayo Clin Proc 41: , 1966