After exclusion of the right lung, a 12-mm endoscopic trocar is placed into the right thoracic cavity through the fourth intercostal space (ICS), lateral to the nipple. The pleural space is insufflated with carbon dioxide at a maximum pressure of 8–10 mmHg, usually 6 mmHg, and the 30° endoscopic camera is inserted. A 1.5–2.0 cm incision is used as a working port in the same ICS for the patient-side surgeon. Additionally two 8-mm port incisions are made in the second and sixth ICS to allow insertion of the left and right instrument arms. The right instrument arm generally is positioned 4–6 cm lateral to the working port in the sixth ICS. The left instrument arm is positioned medial and cephalad to the right arm in the second or third ICS. The fourth arm trocar is placed in the midclavicular line in the 4th or 5th ICS [14], dependent on the patient’s rib direction and ICS. Two 16 F Angiocatheters are inserted in the 6th and 4th ICS laterally respectively for the placement of pericardial stay sutures (Figs. 5.8 and 5.9).

CPB is initiated with kinetically assisted bicaval venous. The intrathoracic part of the operation began robotically with pericardiotomy and placement of pericardial stay sutures. The pericardium is opened longitudinally 1.5 cm anteriorly to the phrenic nerve (Fig. 5.10). The incision is extended superiorly to expose the superior vena cava and then extended inferiorly to the diaphragm to visualize the inferior vena cava. The pericardium stay sutures are placed on the right side of pericardium to rotate the heart for optimal exposure of the atrium (Fig. 5.11). And the 3rd pericardium stay suture is placed on the left superior side of pericardium through anterior chest (16 Ga Angio) to expose the aorta (Fig. 5.12).

The space between the vena cavae and the pulmonary veins are dissected clear (Figs. 5.13 and 5.14). And the linear tapes are placed around the inferior and superior vena cavae (Figs. 5.15 and 5.16). The aortic occlusion is performed with a Chitwood cross-clamp via the midaxillary line in the fourth ICS (Figs. 5.17 and 5.18). Antegrade cold blood cardioplegic solution is administered directly through the anterior chest (the second ICS) with a 14 Ga Angiocatheter (Figs. 5.19 and 5.20).

After snaring of the superior and inferior vena cavae, the right atrium is opened (Fig. 5.21). The atrial retractor is introduced into the right atrium through the fourth robotic arm to expose the atrial septal defect (Fig. 5.22). Cardiotomy suction is passed through the working port by the patient-side surgeon. After thorough exploration, ASD is closed directly using 4-0 Gore-Tex running suture or autologous pericardial patching, depending on the size and location of ASD (Figs. 5.23 and 5.24). The knot tying is performed extracorporeally by patient-side surgeon using a knot pusher. And the atrial leakage is identified before closing right atrium. If the moderate to severe tricuspid valve regurgitation is diagnosed, the retractor is removed to expose the tricuspid valve and ring. The tricuspid valve plasty is performed using De Vaga technique. The result of tricuspid valve plasty is evaluated (Figs. 5.25 and 5.26). The right atrium is closed with double-layer 4-0 Gore-Tex running suture (Fig. 5.27). The deairing is done through the cardioplegia Angiocatheter. Then the aortic puncture site is closed using 4-0 Gore-Tex (Fig. 5.28). After adequate hemostasis achieved, the robotic arms are removed and a chest tube is inserted through right arm porthole. The right femoral artery is reconstructed after removing of the cannulas.

For ASD closure on beating heart, the aortic occlusion and cardioplegic solution administration can be avoided [15]. Under mild hypothermic conditions (rectal temperature, 34–35 °C), CPB full flow is maintained with mean systemic pressure more than 60 mmHg. To avoid air embolism, carbon dioxide with 6–8 mmHg is insufflated continuously into the chest for air displacement. On beating heart, a right atriotomy is performed under SVC and IVC snared with same techniques mentioned above, and ASD is exposed with atrial retractor by the 4th arm. A small suction catheter is placed in the right atrium, not in the left atrium through the working port. The direct closure with running suture or autologous pericardium patching can be used (Figs. 5.29, 5.30, 5.31, 5.32, and 5.33). As the inter-atrial septum is closed, the lung is briefly inflated, and the inter-atrial suture line is secured when there is no evidence of retained air in the left atrium.

Advantages of this method include avoidance of ischemia-reperfusion injury, performance of surgery in a more physiological state of the heart, decreased use of inotropic medications, and shorter hospital stay [16]. In addition, proximal aortic arteriosclerosis is the source of macro- and microemboli at the time of placement and release of the aortic cross-clamp. Potential concerns related to this technique may include performance of surgery in a relatively blood-filled field, limited surgical precision due to difficult exposure, risk of air embolization, and limited ability to perform very large ASD closure procedure on beating heart [16].

In fact, the operations can be performed without difficulty because the atrial retractor through 4th arm and small suction catheter from the working port could provide adequate visualization of the operative field. In addition, the concomitant surgery of tricuspid valve repair is easily performed. In our study, the complications related to beating heart ASD repair are not observed, such as, strokes or residual atrial septal defect due to dehiscence of the atrial suture line.

For the prevention of air embolism, each patient is positioned with the right chest elevated approximately 30°. Furthermore, the left atrium is kept full without suction in it during operation, and throughout the procedure carbon dioxide with 6–8 mmHg is insufflated continuously into the chest for air displacement. De-airing of left atrium at the end of the procedure is easily done.

Based on this knowledge, it seems reasonable to perform robotic beating-heart ASD closure surgery with on-pump beating heart conditions. This technique is simple and it shortens the duration of CPB and total operation. Besides, this technique does not increase the risk of central nervous system (CNS) injury. It is not possible to determine with certainty whether minor neuron-cognitive disorders due to microembolization occur. The neurocognitive evaluation is an important aspect that needs to be further investigated.

Possible contraindications to robotic beating-heart ASD repair may include the presence of mobile vegetations in patients with infective endocaditis or large left atrial thrombi, due to the risk of embolization. Inadequate experience of console surgeon certainly is contraindication to beating heart surgery.