The study protocol was approved by the Ethics Committee for the Protection of Human Subjects at the Zhongshan Hospital Fudan University (Shanghai, China). Individual patient informed consent was not required in this study. The study design was a retrospective observational study.
Patient Demographics and Characteristics
Between June 2016 and August 2017, a total of 14 consecutive patients who underwent redo isolated tricuspid valve operations with minimally invasive beating heart technique through a right lateral thoracotomy at Zhongshan Hospital, Fudan University were retrospectively reviewed. Mean patient age was 54.0 ± 8.3 years (range, 43 - 64 years), and 9 patients (64.3%) were women.
The indications for tricuspid valve operation of our present group were the presence of severe or more tricuspid regurgitation along with New York Heart Association class III-IV or more symptoms or other signs of right heart failure, including uncontrolled pedal edema, ascites, pleural effusion in 13 patients, and mechanical tricuspid valve dysfunction in 1 patient.
All patients had medical history with previous cardiac operations and underwent first-time reoperative cardiac procedures. The previous cardiac operation was performed through a median sternotomy. 6 patients (42.9%) had previously underwent a mitral valve replacement, 1 patient (7.1%) had underwent mitral valve replacement and tricuspid valve repair, 1 patient (7.1%) had underwent a tricuspid valve replacement because of Ebstein anomaly, 5 patients (35.7%) had underwent mitral valve and aortic valve replacement, and 1 patient (7.1%) had underwent a Ebstein repair.
The tricuspid valve pathologic characteristics included annulus dilatation, leaflet restriction and thicken associated with severe or more tricuspid regurgitation in the majority patients (13 patients [92.9%]), except 1 patient with mechanical failure after tricuspid valve replacement.
Surgical technique
Although, the techniques of minimally invasive tricuspid valve surgery have been reported elsewhere, there are still many differences in details of our center. Following induction of anesthesia and intubation with a dual lumen endotracheal tube, all patients were routinely placed with transesophageal echocardiography (TEE) and implanted with endocardial temporary pacing lead through right internal jugular vein by the anesthetist. Patients were then positioned supine with the right shoulder elevated 30 degrees. In our center, cardiopulmonary bypass was established by femoral platform. An oblique incision was usually made in the right groin to expose the femoral artery and vein for cannulation. Utilizing a Seldinger technique, the femoral artery was cannulated with a16 Fr to 20 Fr arterial cannula (Edwards Lifesciences, or Medtronic, USA), and the femoral vein was cannulated with a 24 Fr venous cannula (Edwards Lifesciences). TEE was used to assist placement of the femoral venous cannula, which was inserted up to the superior vena cava.
After initiation of cardiopulmonary bypass, vacuum assistance (10 to 15 cm H2O) was usually used to accomplish total drainage of the atrium in the authors' center. A 5 cm right anterolateral thoracotomy was performed over the fourth intercostal space. The fourth intercostal space was entered. Lungs were deflated and the right atrium was identified by pushing on the atrial wall with long forceps. Pericardial and atrial tissues are usually bonded tightly as a result of previous operations. Therefore, the pericardium was not dissected from the right atrium, but incised directly. Using traction lines to expose the right atrium and keeping the balance between arterial inflow and venous drainage, the tricuspid valve visualized and replacement or repair was being performed on the beating heart with good visual field.
Follow up
The follow up was performed by direct interviews in our outpatient department to evaluate their clinical status, or by telephone contact with patients and/or family members. The 3 months follow up was 100% complete. The midterm follow-up (37.7 ± 5.5 months) was 85.7%.
Statistical analysis
Surgical treatment technique was not randomized, but rather was determined by the best medical judgment for each individual case. Data were collected from chart review, and were entered into a dedicated Microsoft Excel table.
Categorical variables are represented as frequency distributions and single percentages. Values of continuous variables are expressed as a mean ± standard deviation (SD). All analyses were performed with the SPSS statistical package version 17.0 (SPSS Inc, Chicago, IL, USA).