Comparative study of total thoracoscopic mitral valve surgery and traditional open mitral valve surgery :propensity score matching study
Authors: Zhang Xiaofei , Yu Haifeng , Ni Bin 
Published: May 2024

Background: Conventional median open mitral valve replacement surgery usually requires a 20-30cm size incision to ensure adequate visual exposure. So, while we complete the valve replacement, it also brings about a series of problems. The appearance of TV thoracoscope changes the exposure of the surgical field. Because the microscopic field is enlarged, it not only makes the surgical vision clearer, but also greatly shortens the incision, reduces bleeding, and conceals the incision, minimizing the trauma and shortening the postoperative recovery time, which is in line with the concept of modern health. Aim: All technological innovation is controversial in the early stage, and it is such debate that can promote the progress and development of technology.This study was conducted in the context of this debate to summarize the experience of Total thoracoscopic mitral valve surgery in our center.Total thoracoscopic mitral valve replacement surgery and traditional median incision mitral valve replacement surgery were compared by the propensity score matching method.Evaluate its safety and merits. Methods: From January 2018 to December 2020, a total of 139 patients in the thoracoscopic group were eligible in the cardiothoracic surgery department of our hospital, and 1066 cases of traditional median sternotomy mitral valve replacement. After propensity score matching, 125 patients were selected in the thoracoscopic group, among 1066 patients with median incision MVR, 1:1 matched to 125, as the control group in the thoracoscopic group. Results: The results showed that the mean operative time in the thoracoscopic MVR group was significantly longer than that in the control group (185.73 ± 43.04 vs. 164.58 ± 40.28, p=0.0016). Similarly, both the mean CPB time and aortic block time were significantly longer than those in the control group (108.37±30.57min vs. 79.18±17.65min, p <0.0001; 66.59±29.63min vs. 45.09±19.68min, p <0.0001. Moreover, the proportion of patients with CPB greater than 120min and aortic block greater than 90min was significantly higher than the control group (24.1% vs. 3.2%, p <0.0001,14.4% vs. 2.4%, p=0.0237). In addition, there was no significant difference in the mean ICU observation time between the two groups (49.35±34.51h vs. 48.72±25.89h, p=0. 8792). Differently, the mean endotracheal intubation time was significantly lower in the thoracoscopic MVR group compared to the control group (18.52±6.07h vs. 25.45±14.18h, p=0.0032). Similarly, the length of stay in the thoracoscopic group was 9.13 ± 4.58 days, which was significantly lower than 11.12 ± 5.76 days in the control group (p=0.0004). There was no significant difference in the postoperative hemoglobin concentration or platelet count between the two groups of MVR patients. Mean intraoperative bleeding volume in the thoracoscopic MVR group was significantly less than that in the control group (158.37±100.91ml vs.250.74 ± 81.34, P <0.0001). Similarly, the mean postoperative discharge in the thoracoscopic MVR group was significantly than in the control group (428.39±361.38ml vs. 514.07 ± 347.92ml, p=0.0383). For patients with postoperative blood products, there were 37 (29.6%) in the thoracoscopic group and 33 (26.4%) in the control group. There was no significant difference between the two groups. Similarly, there was no significant difference in the mean total hospital costs between the two groups. Conclusion: This study shows that it has feasibility and safety for total thoracoscopic mitral valve replacement for mitral valve lesions, which can reduce the time and stay of the hospital compared with conventional direct surgery, and obtain good minimally invasive and cosmetic effect, and lay a theoretical and clinical foundation for the application of thoracoscopic technology in cardiac surgery, which has important scientific significance.