Port Access and Minithoracotomy Mitral Valve Surgery

This video demonstrates the technique of port access mitral valve surgery.

Patient Selection
• Any patient with mitral valve disease with or without tricuspid disease, atrial septal defect, and atrial fibrillation can be considered for a port access approach.
• The preoperative exam determines the suitability of the particular patient.
• If a thick chest wall or a prominent pectus deformity are found on exam, the procedure may be better suited to a robotic approach. A pectus deformity of the lower sternum and xiphoid can be approached via port access. A hostile groin necessitates a percutaneous cannulation or alternate arterial access, usually subclavian.
• A computed tomography scan of the total aorta should determine the optimal arterial cannulation, and it often reveals unanticipated disease and limited dissections from the catheterization laboratory. Preoperative or intraoperative transesophageal echocardiograms (TEE) document aortic atheroma. Grade III and IV atheroma are contraindications, while patients with grades I and II atheroma can undergo retrograde perfusion safely in most cases.
• An inferior vena cava (IVC) filter is not a contraindication, but successful venous cannulation should be performed before other incisions are made.

Patient Positioning
• The patient is positioned supine with a soft roll under the right scapula, elevating the chest at a 30° angle. This gives access to both groins.
• An EndoPlege cannula is inserted in the right internal jugular vein and positioning is confirmed with dye and fluoro.
• If the right atrium will be opened, a 15 Fr cannula is also inserted and connected directly.

Incisions
• Doppler location of the femoral artery and vein enables a small groin incision.
• Dissection is minimal and limited to the anterior surface of the femoral vessels.
• The chest incision is in a line from the nipple toward the axilla, beneath the border of the pectus muscle.
• The chest is entered through the 4th or 5th intercostal space, directly above the pulmonary veins.

Cannulation
• Cannulation is the Seldinger technique and is performed through a single purse string suture in the vein and a double purse string suture in the artery.
• Venous and arterial wires should pass easily, and they should be visualized in the superior vena cava (SVC) and descending aorta, respectively, before dilation and cannula insertion.

Cardiopulmonary Bypass and Operation
• Once cardiopulmonary bypass (CPB) is instituted and the heart decompressed, the pericardium is opened 2-3 cm above and parallel to the phrenic nerve. Stay sutures are placed at the SVC and IVC reflections and over the RSVR and brought out percutaneously.
• The aorta is cross-clamped with a transthoracic Mohr clamp or the endoballoon. The authors do not use adenosine, but simply lower the flow as clamping occurs.
• One liter of del Nido cardioplegia is given antegrade and 500 ml is given retrograde. If the Mohr clamp is used, antegrade is given through a long 14 gauge angiocatheter.
• The left atrium is opened along Sondergaard’s groove, and the mitral retractor is placed.
• The valve is visualized and inspected and the appropriate repair performed, for example, neochords, patch, or resection.

Closure and CPB Wean
• A vent is placed through the right SPV and the left atrium is closed in two layers.
• The heart is filled and respiration is begun to de-air the heart.
• One liter of retrograde hotshot is given as pacer wires are placed and brought out through the retractor post stab wound. With the patient in the Trendelenburg position, the cross-clamp is released. If the Mohr clamp was used, the 14 gauge angiocatheter is allowed to bleed through two purse string sutures as the Mohr clamp is flashed and the root de-aired.
• Once pacing is begun or rhythm returns, CPB is weaned slowly.
• Once the patient is off bypass with all air evacuated and a satisfactory TEE result, CPB is reinstated.
• The aortic purse string sutures are tied. The LV vent is removed and oversewn, and pericardial sutures and blake drain are placed; the sutures are not tied.
• CPB is then reweaned, the pericardium closed and groin decannulation is performed.
• Protamine is reversed, hemostasis is secured, and the wounds are closed. A pleural blake drain is placed.
• A no. 2 prolene suture is used for pericostal closures to prevent lung herniation.
• Groin seromas are minimized by exposing only the anterior surface of the femoral vessels.

Suggested Reading:

1. Ryan WH, Cheirif J, Prince S, Mack M. Safety and Efficacy of Minimally Invasive Atrial Septal Defect Closure. Ann Thoracic Surgery. 2003;75:1532-1534.

2. Wheatley III GH, Prince SL, Herbert MA, Ryan WH. Port-Access Aortic Valve Surgery: A Technique in Evolution. Heart Surgery Forum 2004;7(6).

3. Ryan WH, Dewey TM, Mack MJ, Herbert MA, Prince SL. Mitral Valve Surgery Using the Classical “Heartport” Technique. Journal of Heart Valve Disease. 2005;14:709-714.

4. Ryan WH, Brinkman WT, Dewey TM, Mack MJ, Prince SL, Herbert MA. Mitral Valve Surgery: Comparison of Outcomes in Matched Sternotomy and Port Access Groups. Journal of Heart Valve Disease. 2010;19:51-59.