Results
During the study period 68 consecutive patients underwent minimally invasive tricuspid valve surgery. The mean age was 69+/-14 years and 48 (70%) were female. A redo operation was performed in 5 patients. Table 1 details preoperative patients’ characteristics. Isolated tricuspid valve repair was performed in 4 patients, while in 64 cases it was associated with mitral valve surgery +/- AF ablation.
In 17 cases (25%), including the five patients who underwent a redo operation, an endoaortic balloon clamp was used; in the remaining 51 patients (75%) an external cross clamp was applied. The tricuspid valve was repaired in all cases with a restrictive annuloplasty using a rigid ring (Table 2). In combined interventions mean CPB time was 156 +/- 43 (minutes), mean cross clamp time was 118 +/- 32 (minutes). In isolated TVr mean CPB and cross clamp time were 105 +/- 41 and 74 +/- 6 minutes respectively. Operative times decreased over the study period: the analysis of the 2-year interval periods showed that mean CPB time shortened from 186±48 minutes in the period 2013-2014 to 127±16 minutes during the period 2019-2020 (anova p=0.002); mean cardioplegic arrest time decreased from 132±28 minutes in the first two years to 97±13 minutes in the period 2019-2020 (anova p=0.02).
Conversion to sternotomy was necessary in one case for uncontrolled bleeding from left atrial appendage, damaged by external aortic clamp. One patient was taken back to theatre for excessive bleeding that was ultimately controlled through the original right mini-thoracotomy access. A new perioperative cerebral stroke occurred in one patient; two patients sustained an episode of transient ischemic attack during the early postoperative course. The mean stay in ICU was 56 +/- 48 hours and was prolonged for five patients who suffered low cardiac output syndrome requiring drug support and, in one case, renal replacement therapy with CVVHD. Cardiac enzymes were routinely evaluated during the first postoperative days (table 3), no patient sustained a perioperative myocardial infarction. In 25 cases (37%) blood transfusion was performed during the post-operative course. (Table 3. Reports postoperative laboratory tests).
Three patients developed infection (n=1) and lymphoceles (n=2) with dehiscence of the inguinal wound; no complications were registered at the mini-thoracotomy site. All patients were successfully discharged after a mean hospital stay of 8.9 +/- 7.2 days.
Survival at a 5-year and 8-year follow up was 100% and 79%, respectively (Figure 1) . (Table 4. Reports early postoperative outcomes). At follow-up no patient had an NHYA class greater than two, only one patient was re-hospitalized for heart failure for an atrial fibrillation episode. One patient was hospitalized for a pericardiocentesis twenty days after discharge
No severe tricuspid regurgitation was evident at echocardiographic follow up (Figure 2 ). Five patients had 2+ TR.