Manipulation of a beating heart requires patience and slow, gentle maneuvers. Do not occlude coronary arteries until there is sufficient exposure and stabilization of the target area. The comfort level required to confidently perform the anastomosis, and indeed the success of the procedure, are directly related to good exposure and stabilization.

The following procedures illustrate techniques for exposing the vessels on the posterior wall of the heart. For clarity, assume the use of a median sternotomy for access.

Vessel Exposure Using Deep Pericardial Retraction Sutures

Traction placed on deep pericardial retraction sutures (DPRSs) is used to rotate and vertically displace the apex of the heart. The importance of the DPRSs, used in combination with the Trendelenburg position and table rotation, for cardiac manipulation and vessel exposure cannot be overstated. However, traction placed on the DPRSs and pressure placed on the ventricle by sponges or other packing material can cause significant drops in blood pressure if they are not instituted gradually. DPRSs are placed in the following locations (see figure below):
The first DPRS is placed posterior to the phrenic nerve at the level of the left superior pulmonary vein (LSPV).
The second DPRS is placed posterior to the phrenic nerve, about two-thirds of the distance toward the diaphragm.
The third DPRS is placed in the posterior pericardium between the IVC and the LSPV.
Traction on the first and second DPRSs will allow rotation of the heart and expose the LAD, diagonal, and high marginal arteries.
Traction on the first and third DPRSs will vertically displace the apex of the heart and expose the OMs, PLB, and PDA.
Suturing the diaphragmatic pericardial edge to the skin will create additional room and exposure for easier grafting of the posterior vessels.

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Vertical Displacement for Exposure of Obtuse Marginals and PDA by James C. Hart, M.D.

The following displacement techniques, used in conjunction with deep pericardial retraction sutures, the Trendelenburg position, and table rotation, provide good vessel exposure while minimizing cardiac manipulation and maintaining hemodynamic stability (see figure below):
1. Extend the pericardial resection laterally at the level of the diaphragm. (view RealVideo Clip)
2. Place warm pads in the posterior pericardial well.
3. Do not place a deep pericardial retraction suture in or suspend the right edge of the pericardium.
4. Open the right pleural space and elevate the right sternal edge to create space in the right chest for the rotated and displaced heart without compressing the right ventricle and right atrium. Excellent exposure of the lateral wall is obtained with minimal hemodynamic compromise.
5. Rotate and displace the heart until the apex is under the right sternal edge. OMs and the PDA will be readily accessible in this position. (view RealVideo Clip)

OM-PDA Exposure Techniques by Ted Spooner, M.D.

A pericardial-based retraction system effectively supports the heart while allowing access to coronary arteries on the inferior and lateral walls of the heart (see figure below). A mechanical stabilizer can then be used to immobilize the target area. The retraction system is composed of stockinet material (2 cm × 30 cm) and a 36-inch braided suture. To set up the retraction system:
1. Expose the posterior pericardium by manually retracting the heart to the patient’s right.
2. Pass the suture through the pericardium at a point just behind the coronary sinus and directly beneath the origin of the most distal coronary artery (usually halfway between the left inferior pulmonary vein and the IVC).
3. Pass the suture through the midpoint of the stockinet.
4. Have an assistant gently retract the inferior portion of the heart.
5. Draw the stockinet into the pericardium and tie the suture.

The middle of the stockinet is now attached to the posterior pericardium, and the two free ends of the stockinet are lying outside the chest. As traction is applied to the two free ends, the point of fixation moves in an anterior (not lateral) direction. The following techniques provide good vessel access:
Inferior surface of the heart (PDA and RCA) — Spread the free ends of the stockinet to the right and left sides of the incision. Pull the ends in a cranial direction.
Circumflex marginal arteries — Move the free ends of the stockinet to the left lateral side of the heart. Pull the ends toward the patient’s right shoulder (the marginal artery should be oriented between each end of the stockinet). Attach the free ends to the drapes with a clamp.
To enhance exposure, rotate the table to the right and use the Trendelenburg position.

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