The technical challenge of off-pump coronary artery bypass grafting is to expeditiously perform accurate coronary ­anastomoses on constantly moving target vessels, typically 1–2 mm in diameter. Understanding the stabilization devices is critical as is the various methods of optimizing exposure of the target vessel [2]. Commercially available synthetic beating heart model includes a simulator from the Chamberlain Group, which includes a compressor and controller (Fig. 19.2a), and one developed by EBM, which is motor driven (EBM, Tokyo). Tissue-based models using explanted porcine hearts include the Ramphal simulator, which is a high-fidelity, computer-controlled simulator that can be employed in many aspects of training (Fig. 19.2b). This educational approach permits the surgeon to become familiar and achieve some degree of proficiency before attempting this technique in the clinical setting.

One part-task simulator for aortic cannulation is the HeartCase model with the synthetic thoracic aortic attachment. Using a syringe or a pressure bag, normal saline can be instilled into the synthetic aorta for pressurization. A tissue-based model used at the Boot Camp is a porcine heart in which the coronary sinus, coronary arteries, and aortic arch vessels are oversewn (Fig. 19.3a) [5, 28]. The ascending aorta with the arch and a portion of the descending aorta is pressurized with a bag of saline. Another model utilizes the porcine descending thoracic aorta, which is prepared by oversewing the intercostal vessels, securing it in a plastic container, and pressurizing it using saline (Fig. 19.3b) [4]. The tissue-based models are realistic, permitting multiple cannulations. Also, they can serve as thoracic aortic surgery anastomosis simulators [4].

Right atrial or bicaval cannulation for cardiopulmonary bypass is simulated using the porcine heart model placed in a container. Understanding the anatomy, suture placement, and cannulation are the primary objectives. Ideally, atrial cannulation is performed as part of other procedures, such as aortic cannulation. In order to simulate atrial cannulation in a more realistic, beating heart setting, the Ramphal simulator can be used.

Used in the training of perfusionists and surgeons, cardiopulmonary bypass simulators are intended to be highly interactive [4, 5]. The simulators provide multiple physiologic conditions and permit the trainee to manage the steps preceding and during cardiopulmonary bypass, including intraoperative crisis management. The Ramphal simulator is thus well suited for cardiopulmonary bypass simulation. Other “high-tech, high-fidelity” cardiopulmonary bypass simulators, such as the Orpheus perfusion simulator (ULCO Medical), are commercially available with assessment modules, recognizing that such simulators are expensive (Fig. 19.4). A commonly employed method to learn about cardiopulmonary bypass circuit is to have access to a perfusion pump and arrange a tutorial with the perfusionist.

Synthetic models are adequate in teaching important components such as surgical ­anatomy and approach to placing annular sutures [4]. The aortic root model is available from the Chamberlain Group and can be attached to the HeartCase simulator (Fig. 19.5a). The objectives are to train proper needle angle for suture placement, effective knot tying in a deep confined space, placing sutures in the valve sewing cuff, and seating the valve prosthesis. For tissue-based simulation, porcine hearts are placed in a container and situated so as to present the ascending aorta and aortic root (Fig. 19.5b) [4]. The aortotomy is made followed by excision of the leaflets and the muscle bar under the right coronary cusp. Interrupted sutures are placed followed by the placement and seating of the prosthesis. This model lends itself to standardized training, as it is currently used in many centers [4].

The synthetic mitral valve attachment is a silicone-based cylinder placed in the portable HeartCase model (Fig. 19.6a) [4, 6]. The synthetic model provides a method to learn basic components of mitral valve surgery, such as exposure techniques and needle angles, but it is limited in its fidelity [4]. To more accurately simulate the mitral leaflets and annulus requires the use of a porcine heart model, which is placed in the container and situated so as to present the left atrium and mitral annular plane. The left atrium is opened and the mitral valve and annulus exposed in an “anatomically correct” configuration (Fig. 19.6b) [4, 6]. Interrupted annular sutures are placed and annuloplasty ring situated and secured. The porcine model is realistic but can pose some challenges with anterior-posterior orientation in the setup [4].

For the tissue-based aortic root replacement simulator, explanted porcine hearts are placed in the container and situated so as to present ascending aorta and aortic root [4]. The porcine aorta and root are resected after creation of the coronary ostial buttons. A composite valve graft (or just a Dacron graft) or an expired aortic homograft (CryoLife, Inc. Kennesaw, GA), if available, is prepared and anastomosed as a root replacement using polypropylene sutures for coronary button reimplantation [4]. This realistic, tissue-based model has been helpful in familiarizing the trainee with the complexity of this procedure [4].