Our study shows that TVR via total thoracoscopic surgery, compared with TVR via median sternotomy, has an obvious advantage in terms of decreased perioperative blood loss, and increased speed of postoperative recovery (based on the length of ICU, mechanical ventilation time and hospital stay). Meanwhile, the number of patients received transfusion was better compared with the control group. Total thoracoscopic TVR is more technically challenging and difficult for surgeons, which increases the length of time of CPB. However, there were no significant differences in the operative times between the study and control groups because it was not necessary to dissect the pericardial conglutination, and the postoperative wound closure is easier to perform. By assessing pain scores and the condition of using opioids and sleeping pills, the patients in the study group had less pain and better comfort compared with the control group. Complication rates were calculated, most of the complications (renal dysfunction, liver dysfunction, hydrothorax, severe pulmonary infection) and total complications in the study group were significantly lower than those in the control group. Follow-up evaluations through clinical or telephone visits revealed excellent surgical outcomes in both groups. Total thoracoscopic TVR is not inferior to traditional surgery concerning cardiac function and recurrence of tricuspid valve regurgitation.
For the patients who enrolled in our study, TVR is the better choice. We believe that submitral structures are damaged after mitral valve replacement, and this damage inevitably affects the heart fiber skeleton that can cause the mechanical balance of the heart fiber skeleton to change. Gradually, the fiber skeleton is displaced, unbalanced, and affected by the TV apparatus[30]. This mechanical change of the TV and heart fiber skeleton is irreversible; even with TVP, most patients will still have severe tricuspid valve regurgitation after 5–7 years. Furthermore, all patients had obvious annular dilation and crispation of the valve with or without calcifications, performing TVP should be weighed carefully due to the high risk of broken or loose sutures and tricuspid annular laceration, especially for the six patients who had previously undergone TVP. In a word, Tricuspid valve replacement is undertaken when valve repair is not technically feasible or predictably durable. In many patients with secondary TR with marked right ventricular remodeling, leaflet tethering, or stenosis cases, valve replacement can be considered as a primary treatment strategy[1, 26]. In contrast to the mechanical prosthetic valve, bioprosthetic valves have more advantages for the opening area and thrombus formation rate. Furthermore, with the development of interventional valve technology, we believe that the bioprosthetic valve failure can be resolved in the long term through more minimally invasive interventional techniques. Besides, when the delayed severe atrioventricular block occurs, we can place a pacing lead through the opening of bioprosthesis. These advantages made us inclined to choose a bioprosthesis for TVR.
We have some experience in performing total thoracoscopic TVR. We chose to make an incision in the 4th intercostal space on the right anterior axillary line for the main working port and then chose to make two incisions in the 3rd and 5th intercostal spaces as the camera and auxiliary incisions, respectively (Fig. 1). These incisions ensured improved views of the operative field, and flexibility of the operative manipulations, simultaneously, they also yield better cosmetic effects (a postoperative scar is shown in Fig. 4). To prevent unnecessary bleeding, injury, and the risk of atrial rupture, we incised the pericardium and right atrium together without dissecting the pericardial conglutination, which is the most time-consuming part of the classical approach. In some cases, poor drainage of the femoral vein and internal jugular vein cannulations made the surgical field unclear, and we could not block the vena cava by taping the superior and inferior vena cava because of Atri-pericardium incision. Therefore, pledget or Foley’s catheter was placed in the orifices of the superior or inferior vena cava (Fig. 2-A, 2-B), Use of vena cava negative pressure assist drainage technique can ensure satisfactory vena cava drainage, and a right atrium vent was inserted on the coronary sinus ostium. This process ensures a clearer surgical field. The entire TV was preserved, and the leaflets were folded into the annulus instead of removing them; therefore, we were able to maintain the integrity of the chordae and papillary muscles. Given the irregular geometry of the right ventricle and the thinner right ventricular wall compared with the left side of the heart, the chordae and papillary muscles served as significant mechanical fulcra to stabilize the right ventricular structure and minimize ventricular enlargement. Besides, these structures are important to enhance the contractile efficiency of the right ventricle by maintaining the concentric contraction of the right ventricle. Also, preserving the TV can reduce the risk of bleeding, myocardial injury, and even right ventricular rupture when the leaflets and the surrounding tissue are removed. It is also technically important to prevent and handle the occurrence of an atrioventricular block during the process of TVR. Other than TVP, the process of TVR inevitably requires interrupted mattress sutures at the annulus of the septal leaflet. We consider that the sutures, when performed at the root of valve, keep off the Koch triangle to prevent damage to the AV node. If the annulus of the septal leaflet is sutured too deep, the heart rate will slow down at the time of knotting, and a severe atrioventricular block can be observed on the ECG monitor. Under this condition, the knotted suture is removed, the suturing is reperformed, and the depth of the suture is adjusted (Fig. 3). Conversely, interrupted mattress sutures are made on the valve leaflet with re-knotting.