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Ross Procedure


Ross Procedure
Keywords: autograft, aortic root, pulmonary root, inclusion technique, aortic valve replacement

Abstract
The Ross procedure uses the pulmonary autograft to replace the diseased aortic valve and root. With appropriate patient selection and technical modifications, the durability of the autograft can be significantly improved. The Ross procedure continues to be a safe, effective and coumadin- free alternative for aortic valve replacement across all age groups.
·    The Ross procedure replaces the diseased aortic valve with a viable pulmonary autograft and uses an appropriate conduit (e.g., a cryopreserved pulmonary homograft) to reconstruct the right ventricular outflow tract (RVOT).
·   As initially described, the autograft was placed as a scalloped subcoronary implant. The complexity of the operation and concerns regarding autograft insufficiency have limited widespread adoption of the procedure. The subsequent use of the full root technique, in addition to the increasing availability of homografts, has increased interest in the operation.
·  More recent concerns regarding autograft dilation and neoaortic insufficiency have led to further refinements.

Step 1. Surgical Anatomy
· Relevant surgical anatomy centers on proper enucleation of the pulmonary root and undistorted implantation into the left ventricular outflow tract (LVOT). In adults, we currently place the pulmonary autograft within an appropriately sized Dacron conduit to prevent pulmonary autograft root dilation and subsequent neoaortic insufficiency. This technique also stabilizes the sinotubular junction.
·   A thorough understanding of the anatomic relationships between the pulmonary and aortic valves is critical (Fig. 17.1).

Step 2. Preoperative Considerations
· The growth potential of the autograft, favorable hemodynamics, and avoidance of anticoagulation have made Ross procedure the operation of choice for infants, children, and adolescents with aortic valve disease requiring aortic valve replacement. It should also be considered for young adults who wish to avoid anticoagulation or who have endocarditis requiring valve replacement.
·    We have had excellent results using the Ross procedure in adults with bicuspid aortic valves requiring replacement. Recent evidence has suggested a low rate of RVOT stenosis in older patients, which may extend the popularity of the operation for patients up to the sixth decade.


·    It is important to inform patients about the possibility of autograft failure. Avoiding the Ross operation when a significant geometric discrepancy between the pulmonary and aortic annuli is detected preoperatively should minimize this complication. If a moderate-sized discrepancy exists between the aortic and pulmonary roots, a number of techniques to minimize mismatch have been developed; the surgeon should be familiar with them before performing the procedure.
·  Patients with an abnormal pulmonary valve, a complex connective tissue disease, or an immune complex–mediated disease with known valvular sequelae should be excluded.

Step 3. Operative Steps
·    A standard median sternotomy is performed. The pericardium is incised, and pericardial stay sutures are placed. Bicaval cannulation is used, which facilitates exposure and avoids venous air entrapment following autograft enucleation. Antegrade and retrograde cardioplegia cannulae are placed, except when aortic sufficiency is present, in which case handheld cannulae may be used. The patient is placed on cardiopulmonary bypass and cooled to 32°C (89.6°F). A vent is placed through the right superior pulmonary vein (Fig. 17.2).
·    The aorta is divided at the sinotubular junction, and the aortic valve is inspected. If no repair option is available, generous coronary buttons are harvested, and the aortic valve and root are excised. The pulmonary artery is transected below the branch pulmonary artery (Fig. 17.3).
·  After visual inspection of the pulmonary valve leaflets, the pulmonary root with the valve leaflets is excised from the RVOT. The incision is initiated in the RVOT across the infundibulum, approximately 4 mm below the pulmonary valve leaflets. A right-angled clamp can be placed through the pulmonary valve to identify the proper site to begin the ventriculotomy. The pulmonary root should be excised with a 3- to 4-mm rim of myocardium (Figs. 17.4 and 17.5).

·    Aberrant coronary arteries coursing across the RVOT should be identified. The dissection extends along the septal myocardium, avoiding the first septal perforator and left anterior descending artery. The dissection continues along the course of the left anterior descending artery posteriorly, avoiding injury to the left main coronary artery (Figs. 17.6 and 17.7).
·  After the autograft is harvested, excessive myocardium is excised from the explanted pulmonary root to avoid LVOT obstruction after implantation (Fig. 17.8).
·    A Hegar dilator is gently passed through the pulmonary valve to select an appropriately sized Dacron tube. We usually pick a tube graft 2 mm larger than the measured size of the autograft to avoid distortion and narrowing. The autograft is secured within the tube graft using running 4-0 polypropylene sutures passed through the myocardium, just below the valve leaflet (Fig. 17.9).
·    After the pulmonary root is secured, the graft is cut at the top of the commissures, and the distal autograft is sutured to the Dacron graft using 4-0 polypropylene (Fig. 17.10). Once the autograft is completely implanted within the graft, a saline test can confirm leaflet competency (Fig. 17.11).

·  The tubularized autograft is sutured to the LVOT using running 3-0 polypropylene (Figs. 17.12 and 17.13). After the proximal anastomosis is complete, the coronary buttons are reimplanted. A portion of the Dacron conduit and the corresponding internal autograft sinus are excised after determining the proper location for coronary reimplantation (Fig. 17.14). The left and right coronary button anastomoses are performed with 5-0 polypropylene sutures. The coronary buttons create structural support to the right and left sinuses of the autograft by stabilizing them to the tube graft. Because of concerns regarding the nonsupported non-coronary sinus, we suture a piece of homograft inside the noncoronary sinus to the corresponding wall of the Dacron conduit (Fig. 17.15).
·   An appropriately sized pulmonary homograft is used to reconstruct the RVOT. The distal anastomosis is performed below the bifurcation. The proximal suture line is completed with 4-0 polypropylene (Fig. 17.16).
·    The distal suture of the tubularized autograft is completed (Fig. 17.17).


Step 4. Postoperative Care
·  Good postoperative care mandates ensuring excellent hemostasis before leaving the operating room. Any bleeding, especially from the LVOT suture line or coronary buttons, should be repaired, if necessary, on cardiopulmonary bypass using cardioplegic arrest.
·    Placement of blind sutures at the proximal suture line should be avoided because autograft leaflets may be injured.
·    Transesophageal echocardiography should confirm good valve function and lack of an LVOT gradient.
·  Avoidance of hypertension should be emphasized in the intensive care unit. Generally, myocardial function is good, and inotropic support is not necessary.

Step 5. Pearls and Pitfalls
·    Meticulous technique is imperative to avoid bleeding.
· When enucleating the autograft, a definite tissue plane can be identified between the pulmonary root and surrounding structures. This is most easily identified by initiating the enucleation on the right (aortic) side of the autograft.
·    Proper alignment of the autograft in the LVOT is mandatory for a successful outcome.

Bibliography
Bansal N, Kumar SR, Baker CJ, et al. Age-related outcomes of the Ross procedure over 20 years. Ann Thorac Surg. 2015;99:2077–2083.
Chambers JC, Somerville J, Stone S, Ross DN. Pulmonary autograft procedure for aortic valve disease: Long-term results of the pioneer series. Circulation. 1997;96:2206–2214.
Elkins RC, Knott-Craig CJ, Ward KE, Lane MM. The Ross operation in children: 10-year experience. Ann Thorac Surg. 1998;65:496–502. Hampton CR, Chong AJ, Verrier ED. Stentless aortic valve replacement: homograft/autograft. In: Cohn LH, Edmunds LH Jr, eds. Cardiac
Surgery in the Adult. 2nd ed. New York: McGraw-Hill; 2003:867–888.
Luciani GB, Favaro A, Casali G, et al. Ross operation in the young. Ann Thorac Surg. 2005;80:2271–2277.
Ross DN. Replacement of the aortic and mitral valves with pulmonary autograft. Lancet. 1967;2:956–958.