Tricuspid valve repair in isolated tricuspid pathology: a 12-year single center experience

Tricuspid regurgitation (TR) often has a secondary nature, resulting from volume or pressure overload in the presence of right ventricular (RV) failure and annular dilatation with structurally normal leaflets [1]. The most common causes of primary TR are infective endocarditis, mechanical damage by pacemaker wires, rheumatic heart disease, Ebstein anomaly, and drug abuse-induced tricuspid valve endocarditis. Indication and timing of surgical intervention remains controversial due to the limited availability of data on isolated tricuspid valve procedures.

Current guidelines suggest that surgery should be carried out as early as onset of signs of RV dysfunction [2]. Valve repair should be preferred over valve replacement for secondary TR, based on the surgeon’s experience, specifics of the valve pathology, and the patient’s condition. Valve replacement should be restricted to those pathologies with severely destroyed and tethered leaflets and to cases with a severe annular dilatation [2]. Most of the current data on surgical therapy of severe TR originate from concomitant procedures on the left sided valves [3, 4]. Though isolated surgical procedures on the tricuspid valve are less common, some reports have compared isolated surgical tricuspid valve repair and replacement and demonstrated that both are feasible for the patients with isolated TR [5].

The aim of this study is to present our 12-years single center experience with isolated surgical tricuspid valve replacement in patients with primary and secondary TR.

Isolated surgical procedures on the tricuspid valve remain a controversial topic, as this type of surgery is known to be associated with high morbidity and mortality [5]. Data on the topic are rather limited [6]. Only 20% of all the surgeries involving the tricuspid valve are isolated procedures [7], and they should be performed rather sooner than later. The mortality of the isolated procedure is higher than of an isolated procedure on any other valve or a concomitant procedure involving tricuspid valve. Part of this high mortality might be explained due to underlying lung pathologies causing the TR and which may impair postoperative recovery. The surgical risk increases with increasing severity of right and left ventricular functional impairment and progression of right ventricular dilatation [8]. In our cohort, patients who were in a critical condition – i.e., those who were ventilated prior to surgery, those who suffered from severe pulmonary hypertension after a prior mitral valve procedure [9], or those in acute septic shock due to acute infective endocarditis - had the worst outcomes. Given the limited sample size, we were unable to run a regression model to study these factors as being potential predictors of mortality. However, it is likely that these may have had a negative impact on postoperative survival of the overall cohort. Indeed, pulmonary hypertension is known to be a negative predictive factor for operative mortality and is seen in many patients who suffer from secondary TR [10, 11].

Previous studies have shown high early- and long-term TR recurrence rates after tricuspid valve repair despite the use of the annuloplasty rings [12]. In our cohort we did not observe any cases of recurrent TR during follow-up, neither after ring-annuloplasty nor after any other surgical technique. McCarthy et al. [12] emphasized an elevated risk of TR recurrence of up to 20% after 8 years in patients undergoing DeVega procedure compared to the patients receiving annuloplasty rings or Cosgrove bands and thus suggested to abandon this technique for the secondary TR. Another group from the University of Rochester reported about 24% of TR recurrences after 5 years in patients with functional TR [13]. In our study, patients who were treated with DeVega technique did not need any repeated intervention within the follow-up. However, in these cases, the indication for the procedure was not functional TR, but either mechanical damage caused by pacemaker wires or an infective vegetation in the absence of leaflet destruction and right ventricular dilatation. Hence, the DeVega procedure was performed mainly to stabilize the TV annulus from the further dilatation, which was in these cases unlikely to happen. In agreement with the results from our study, Eichhorn at al [14]. showed satisfactory results after DeVega annuloplasty in patients with primary TR. This might lead us to argue that this method should not be entirely abandoned, but rather be considered for specific indications in carefully selected patients. Additionally, McCarthy at al [12]. suggested to replace the transvenous pacer leads with the epimyocardial leads, which was performed in all patients in our cohort who required a pacemaker prior to the tricuspid valve procedure.

Patients who received ring or band annuloplasty were not re-operated on the tricuspid valve during the follow-up time (Table 3). Recurrence of TR might be an important reason for the diminished mid- and long-term postoperative survival observed in other reports about patients after tricuspid valve procedures, as redo procedures on the tricuspid valve are associated with extremely high hospital mortality rates up to 37%. In these cases, the redo surgery is mostly performed despite impaired right ventricular function, progressing pulmonary hypertension, and right ventricular dilatation [15, 16].

Two other patients underwent an urgent procedure due to acute endocarditis with impaired coagulation due to sepsis, which is known to increase the risk for bleeding [17].

The overall results of this study showed a 30-day survival of 84.6% and 1-year survival of almost 73%. These results differ slightly from those of Moraca et al. [18], who reported a 1-year survival rate of 80%. Our results differ also from the recent data of the meta-analysis from the Cleveland Clinic, which reported a pooled operative mortality of 8.4% and a late mortality of 12.7% [5]. In our study, the four patients who died within 30 days postoperatively were all in a critical condition before the surgery. Two of them were elderly patients undergoing an urgent redo procedure with manifest pulmonary hypertension (mean pulmonary artery pressure, mPAP> 40 mmHg) and logistic EuroSCORE > 30%. Another patient presented with acute infective endocarditis and severe septic shock who received a peripheral extracorporeal life support (ECLS) preoperatively, a combination which is known to be associated with high mortality rates [19]. The fourth patient died from a cerebrovascular bleeding. We found no significant difference in survival between patients operated on an arrested or beating heart, suggesting that both procedures may be equally safe.

There are only few studies reporting about isolated tricuspid valve procedures. Hence, any new data on this matter are of great interest. Unfortunately, the limited cohort size did not allow to study subgroups according to the tricuspid valve pathology. This could however have provided some additional information on the outcomes for every specific pathology. Furthermore, this was a retrospective observational study and might therefore be susceptible to confounding.

Analyzing a 12-year single center experience with isolate tricuspid valve disease, this study demonstrated that tricuspid valve repair can be performed in these patients with acceptable postoperative morbidity and mortality. Even though redo procedures on the tricuspid valve carry a high mortality, it might be lowered by performing the surgery as soon as the indication occurs. Recurrent TR has a considerably negative impact on the postoperative survival. Thus, the surgical technique should be chosen carefully, according to the patient’s valve pathology.