Tips and Pitfalls in Robotic Mitral Valve Surgery

*Takashi Murashita*

## **Abstract**

Robotic mitral valve repair is now routinely and safely performed all over the world. There are many literatures which showed advantages of reduced blood loss, lower risk of infection, lower risk of atrial fibrillation, shorter length of hospital stay, quicker return to normal activities, and a superior cosmetic result, compared with a conventional sternotomy. However, the introduction of new technique requires a learning curve even for expert mitral valve surgeons. There are complications specifically related to robotic mitral valve surgery, such as major vascular complications, inadequate myocardial protection, and unilateral pulmonary edema. The purpose of this chapter is to characterize the tips and pitfalls of robotic mitral valve repair and to discuss the controversial issues in the contemporary practice.

**Keywords:** robotic surgery, mitral valve repair, complication

#### **1. Introduction**

Since the introduction of robotic mitral valve repair in the late 1990s, the number of this procedure has been increasing worldwide. Many centers have reported excellent outcomes of robotic mitral valve repair [1–8]. In the beginning, it was mainly applied in selected patients with a simple repair case and relatively low risk cases. However, with the accumulation of surgical experience, the indication has been broadened to complicated repair cases or aged patients.

Wang et al. reviewed the Society of Thoracic Surgeons database and compared surgical outcomes of robotic and surgical mitral valve repair in patients aged 65 years and older [9]. They found that robotic mitral valve repair was associated with less postoperative atrial fibrillation, less blood transfusion, and shorter intensive care unit and hospital stay compared with surgical mitral valve repair without a difference in 3-year mortality, heart failure readmission, or mitral valve reintervention.

## **2. Tips and pitfalls**

#### **2.1 Applying to a robot platform**

Robotic mitral valve repair is usually done thorough a right thoracotomy; thus, intra-thoracic pathology such as previous right thoracotomy, severe pulmonary dysfunction, and chest deformity can be a contraindication [10]. Patients at risk

for coronary artery disease should undergo a cardiac catheterization, and severe coronary artery disease requiring coronary artery bypass grafting is another contraindication of robotic mitral valve repair. In addition, significant pulmonary hypertension or severe right ventricular dysfunction is included to contraindications.

Usually, robotic mitral valve repair is done with a 5- to 6-cm right thoracotomy [11]. A specific attention should be paid for inserting robotic instruments into the right chest. The insertion of service ports can injure the right lung, vessels, diaphragm, liver, and mediastinal structures. **Figure 1** shows our regular setup for robotic instruments. The thoracotomy is made through fourth or fifth intercostal space. We carefully review the preoperative computer tomography and decide which intercostal space would give us the best exposure for mitral valve. The port for left arm is usually inserted through second or third intercostal space. The port for left atrial retractor is usually inserted through the same intercostal space with thoracotomy. The port for right arm is usually inserted through sixth or seventh intercostal space. The camera port is inserted one higher intercostal space than thoracotomy.

### **2.2 The interaction between the operator and the assistance**

After the robotic instruments are inserted, the surgeon moves to the robotic console, and the assistant will move to the patient's right side and has an access to the operative field through the thoracotomy. From the console, the surgeons can perform precise movements inside the heart using the mechanical instruments. The mechanical instruments include forceps, scissors, needle holders, and electrocautery. The surgeons use two mechanical instruments, and the changes of the instruments were manipulated by the bedside assistant.

The role of the surgeon on console is to accomplish a mitral valve repair by cutting, suturing, and sizing with two mechanical instruments, whereas, the role of bedside assistant is suctioning the field, suture following, and knot tying. Since the operative field is very limited, the bedside assistant should be trained for knot-tying instruments.

**27**

**Figure 2.**

*Chitwood clamp.*

*Tips and Pitfalls in Robotic Mitral Valve Surgery DOI: http://dx.doi.org/10.5772/intechopen.85241*

optimal [12].

**2.4 Aortic cross-clamp**

**2.3 Establishment of a cardiopulmonary bypass**

sion during minimally invasive mitral valve surgery [1, 3, 6].

atherosclerosis in order to plan an optimal surgical approach [16].

In a robotic mitral valve repair, cardiopulmonary bypass is established either via an antegrade perfusion with a central cannulation or via a retrograde perfusion with a peripheral cannulation. It is a controversy in which perfusion strategy is

Murzi et al. reviewed 1421 patients who underwent antegrade perfusion and 141 patients who underwent retrograde perfusion [13]. They reported that retrograde perfusion was associated with higher incidence of stroke than antegrade perfusion (3.5 vs. 1.1%). In the meantime, LaPietra et al. reviewed 1501 patients, and found that stroke rate was low (about 1.5%) regardless of cannulation technique [14]. Nowadays, several experienced centers routinely apply retrograde femoral perfu-

In establishing the peripheral cannulation, the venous drainage for cardiopulmonary bypass is obtained by a placement of cannula, usually via the right femoral vein and right internal jugular vein. It is essential to introduce cannula under a transesophageal echocardiography to avoid the risk of extravasation, migration of the cannula, or other types of complications [15]. Arterial cannula is usually inserted to the right femoral artery. It is also essential to obtain a preoperative multidetector computed tomography angiography for the assessment of aortoiliac

For aortic cross-clamp, there are basically two options: endoaortic or transthoracic clamp (**Figure 2**). The endoaortic cross-clamp is performed with an

*Left: endoaortic cross-clamping with an endoaortic balloon. Right: transthoracic cross-clamping using a* 

*Cardiac Surgery Procedures*

thoracotomy.

instruments.

for coronary artery disease should undergo a cardiac catheterization, and severe coronary artery disease requiring coronary artery bypass grafting is another contraindication of robotic mitral valve repair. In addition, significant pulmonary hypertension or severe right ventricular dysfunction is included to contraindications. Usually, robotic mitral valve repair is done with a 5- to 6-cm right thoracotomy [11]. A specific attention should be paid for inserting robotic instruments into the right chest. The insertion of service ports can injure the right lung, vessels, diaphragm, liver, and mediastinal structures. **Figure 1** shows our regular setup for robotic instruments. The thoracotomy is made through fourth or fifth intercostal space. We carefully review the preoperative computer tomography and decide which intercostal space would give us the best exposure for mitral valve. The port for left arm is usually inserted through second or third intercostal space. The port for left atrial retractor is usually inserted through the same intercostal space with thoracotomy. The port for right arm is usually inserted through sixth or seventh intercostal space. The camera port is inserted one higher intercostal space than

**2.2 The interaction between the operator and the assistance**

ments were manipulated by the bedside assistant.

*The picture of a standard setup for robotic mitral valve surgery.*

After the robotic instruments are inserted, the surgeon moves to the robotic console, and the assistant will move to the patient's right side and has an access to the operative field through the thoracotomy. From the console, the surgeons can perform precise movements inside the heart using the mechanical instruments. The mechanical instruments include forceps, scissors, needle holders, and electrocautery. The surgeons use two mechanical instruments, and the changes of the instru-

The role of the surgeon on console is to accomplish a mitral valve repair by cutting, suturing, and sizing with two mechanical instruments, whereas, the role of bedside assistant is suctioning the field, suture following, and knot tying. Since the operative field is very limited, the bedside assistant should be trained for knot-tying

**26**

**Figure 1.**
