DISCUSSION
The introduction of minimally invasive techniques in cardiac surgery and the general acceptance of these techniques in the cardiac surgery community was later and slower than other branches. Advances in percutaneous techniques and the emerging competition since the 1990s have led surgeons to try to achieve these excellent results with less invasive methods [6]. Beyond the good cosmetic results, minimally invasive procedures are preferred because of the small size of the incision, less wound infection, less postoperative bleeding, and therefore less need for blood and blood products, and shorter intensive care and hospital stays[7].
With the da Vinci robotic system, the most important disadvantage of endoscopic surgery, the necessity of performing a mirror image operation, has been overcome. These features have provided great advantages for surgeons in terms of endoscopic cardiac surgery. Despite these features, the use of the robotic surgical system in cardiac surgery requires a difficult and long learning curve and process [7]. The disadvantages of the robotic surgery technique are the longer cardiopulmonary bypass and total ischemic time and the possibility of increased morbidity due to these, the possibility of retrograde aortic dissection due to peripheral cannulation, innominate artery occlusion or embolism due to migration if endoaortic clamp is used, and also causing neurological damage by causing aortic dissection. the possibility of air extraction at the end of the operation, the long learning curve due to the difficulty of the technique, and the expensive materials used [8].
The development process of minimally invasive methods has caused some complications. Falk et al. performed a minimally invasive mitral valve operation in 24 patients in the University of Leipzig experience, and aortic dissection occurred in one patient [9]. One patient developed deep venous thrombosis in two video-mediated minimally invasive cases in which Chitwood et al. directly clamped the aorta using right anterolateral thoracotomy and femoral artery and vein cannulation [10]. Glower et al. recommended direct aorta cannulation with a special aortic cannula in order to prevent complications related to embolization and peripheral vessels in operations performed with port accessory technique. [11]. In our study, femoral artery cannulation was preferred due to the fact that our cases were mitral valve patients and the patients did not have peripheral vascular disorders, because it was easier and cheaper, and there were no intraoperative complications. During the postoperative follow-up period, lymphoresis was detected in the femoral cannulation area in 3 patients, and complete recovery was achieved with medical treatment. We think that this complication is caused by the damage to the lymphatic ducts due to the incision parallel to the inguinal ligament we made to achieve better cosmetic results.
During the widespread use of robotic mitral valve surgery, studies on this method have begun to enter the literature. In a meta-analysis by Cao et al., in which 960 robotic and 690 conventional mitral valve surgeries were compared, six studies in which 1650 patients underwent a total of 1650 patients were included, there was no difference between stroke and reoperations, while CPB and cross clamping times were longer in robotic groups, and intensive care and hospital stays were shorter than methods [12]. In the meta-analysis of Takagi et al., in which a total of 3764 patients who underwent robotic and conventional mitral valve surgery in 2020 were compared, it was stated that the CPB and cross clamping times were longer in the robotic group. It has been observed that the need for erythrocyte transfusion is higher in the conventional method, and the duration of intensive care and hospital stay is longer. There was no difference between the two groups in terms of valve dysfunction, renal dysfunction, pneumonia, stroke and mortality [13]. n a study of 2300 patients who underwent mitral valve surgery by Hawkins et al., it was stated that the intraoperative procedure times were longer in the robotic surgery group [14]. In the study group of 142 patients made by Kesavuori et al., there was no difference in perioperative complications in both groups, and 3 patients in the robotic group required ECMO due to low cardiac output, and one patient from the robotic group died [15]. Among the patients we operated in our clinic, there were no patients who needed ECMO due to low flow, but there were 2 patients in the robotic group and 3 patients in the conventional group, who received high-dose inotropic support.
In a population analysis study of 3145 patients undergoing robotic mitral valve surgery performed by Paul et al., it was found that hospital stay was shorter in the robotic group and there was no difference between the two groups in terms of complications [16]. In the study conducted by Wang et al., a total of 1006 patients who underwent 503 robotic and 503 conventional mitral valve surgery were compared, while CPB and cross clamp times were found to be higher in the robotic group, it was observed that the duration of ICU stay and the incidence of atrial fibrillation were lower [17]. The results we obtained in our study also show similar features with the literature data and are supportive.
The removal of air in the heart cavities becomes important in terms of neurological complications in operations performed with robotic surgery technique. As soon as the thorax is opened, it was thought that air embolism, which could cause serious neurological complications, could be prevented by continuously administering carbon dioxide and controlling the removal of air with TEE. As a result of operations in the patients included in our study, neurological complications were observed in 1 patient in the robotic group and 2 patients in the conventional group. Mihaljevic et al. [18] performed a study comparing robotic mitral valve repair (n = 261) versus full sternotomy (n = 114), partial sternotomy (n = 170), and mini thoracotomy approach (n = 114). There was no significant difference between the groups in terms of postoperative mortality, pulmonary complications, neurological complications, and renal failure rates. The incidence of atrial fibrillation and pleural effusion was lowest in the robotic group, resulting in a significant reduction in hospital stay compared to the other groups[19]. However, cardiopulmonary bypass time was significantly longer in the robotic group than in the other groups [19]. We think this is related to the steep learning curve associated with robotic surgery.
Although the number of patients is small in terms of providing a sufficient evaluation in the studies up to date, the main advantages and disadvantages between robotic surgery and sternotomy methods have been clearly demonstrated in the series. The biggest benefit of robotic surgery operations compared to sternotomy is that patients return to their normal activities more quickly. As can be seen in our study, a significant difference was found between the duration of intensive care and hospital stay, especially in young and physically active patients, quicker mobilization and patient comfort were provided, and in older and sedentary patients, a faster recovery process, less pain and more rapid mobilization has been observed. This rapid recovery process is the result of the robotic surgery method that does not disrupt the integrity of the sternum and preserves the sternum integrity with a 4-5 cm smaller incision, creating less tissue damage, less infection possibility, and providing a quick and comfortable recovery. Thoracotomy incision infections are less morbid and cheaper than sternotomy incisions that require muscle flap to close when infected [20]. Another major limitation in robot use is the steep learning curve associated with it; A competent operator requires 150-250 procedures to become a master [21]. However, proponents argue that the costs can be offset by reduced intensive care and hospital stays. There are publications stating that total operational hospital costs do not increase significantly with robotic technology when the advantages are taken into account [22].