To Fix or Not to Fix? That is the Question.

Eventually, the algorithm for when to intervene on the tricuspid valve during left sided valve surgery will be more robust. Better discriminatory preoperative data will be required to sort the role of annular size, right ventricular function, and pulmonary artery pressures. As for now, there is a paucity of evidence that an aggressive approach to fixing moderate functional TR during left sided valve surgery improves clinical outcomes. Can we draw reliable conclusions from a retrospective look at a series of 200 complex reoperative left sided valve surgeries as to whether or not we should concomitantly fix moderate to severe tricuspid regurgitation (TR)?1 It is difficult. Years before the follow-up Echocardiogram the surgeon chose to intervene or not based on a complex set of data which should have included such variables as the degree of TR in sedated and awake setting, the mechanism of TR, the diameter of the annulus in both systole and diastole, the degree of pulmonary hypertension, the degree of right and left ventricular dysfunction, and the ability of the patient to tolerate the additional time required for the repair. Most of these variables have not been detailed in the manuscript and the decision-making algorithm is unclear. To fix or not to fix and how to fix was also affected by the experience of the surgeon, their understanding of the literature and current guidelines, and institutional bias. Propensity analysis of the 60 pairs provides some clarity regarding expected overall survival but adds little when comparing the degree of TR and right ventricular dysfunction at follow-up. The need for concomitant CABG was significantly different between the two groups (17/60 in the non-intervened group and 3/60 in the intervened group, p=0.001). The higher rates of persistent TR and the trend toward more right ventricular dysfunction in the non-intervened group may be due to ischemic cardiac disease. There were no significant differences in the solid endpoints of death during follow-up, the need for reoperation on the tricuspid valve, and post-operative NYHA Class III or IV. No harm was done in adding a tricuspid repair procedure to a difficult reoperative procedure. This is an important conclusion in this series as the indicated procedure was already a reoperation, which carries a higher risk of mortality and morbidity than a first cardiac operation. There were several long-term trends that suggest the tricuspid repairs may have helped: less residual TR and fewer patients with right ventricular dysfunction. But was there any gain of clinical relevance? Only one patient required intervention on the tricuspid valve in each cohort. Many would argue that all of the patients in this series should have had a tricuspid repair procedure and consensus guidelines reflect this opinion. The literature is far less clear. In 2005, Dreyfus et al2 presented a series of 148 patients undergoing mitral valve repair and concomitent tricuspid annuloplasty compared to 163 patients undergoing mitral valve repair alone. The indication for intervention on the tricuspid valve was having an annular size of ≥ twice normal size regardless of the degree of TR. In fact, the mean TR grade was 0.9 ± 0.6 in intervened patients. At follow-up 48% of the non-intervened patients had a TR increase of 2 grades compared to 2% of the intervened patients. In this study NYHA Class was significantly improved in intervened patients. Benedetto et al3 randomized 44 patients undergoing mitral valve surgery with >2+ TR and an annulus ≥40 mm diameter to an additional tricuspid annuloplasty (n=22) or not (n=22). At one year follow-up, TR ≥3+ was present in 0% of the intervened patients and 28% of the nonintervened patients. Six minute walk testing was improved in the intervened patients. These data are frequently cited by proponents of aggressive intervention on the tricuspid valve during left sided valve surgery despite minimal clinical advantages. In some ways, the logic behind this approach is more sound than intervening merely on the basis of functional TR grade. TR is so dependent on hemodynamic loading and unloading characteristics that an anatomical approach assuring that there is enough tricuspid leaflet tissue to cover the orifice makes sense. Much can be learned from following the progression of TR in large series of mitral valve surgery for degenerative disease, where the tricuspid valve was left alone regardless of annular diameter or TR ≤ moderate. Conclusions must be examined closely. For example, two large studies from the Mayo Clinic in 20114 and 20145 found that moderate TR regressed with time and only one patient in the 2011 report and two patients in the 2014 report required reoperation for functional TR. They concluded that intervention on the tricuspid valve was rarely necessary during mitral valve repair surgery. Exactly, the opposite conclusion was presented from similar data from Goldstone et al.6 They reported on 495 patients of which 43% had grade 1-3+ TR. At intermediate follow-up the TR increase was inconsequential in regards to symptoms and grade. Overall, there was only mild increase in TR in those with ≤3+ preoperatively and actual TR regression in those patients with ≥3+ TR. No patient required a reoperation for functional TR and there were survival or functional sequelae in those patients with residual TR in the follow-up period. They did see more right ventricular dysfunction as assessed by semi-quantitative methods. They concluded that “a more aggressive strategy of concomitant tricuspid repair may be warranted. None of these studies examined the results of tricuspid repair in the setting of left sided valve surgery and the latter manuscript concluding that there is value in intervention on the tricuspid valve cannot be supported from the data within. Eventually, the algorithm for when to intervene on the tricuspid valve during left sided valve surgery will be more robust. Better discriminatory preoperative data will be required to sort the role of annular size, right ventricular function, and pulmonary artery pressures. As for now, there is a paucity of evidence that an aggressive approach to fixing moderate functional TR during left sided valve surgery improves clinical outcomes.