**5.1 Patient characteristics**

Baseline characteristics are detailed in **Table 4**. The mean age was 38,8 ± 10,7years, and 30% of the patients were female. All patients were operated on with acceptable predicted operative risk, in-hospital and 3-month mortality. Mean EuroScore II was 2 [1,3-2,5], while estimated 3-month mortality and predicted in-hospital mortality calculated by MELD Score and more specific Tri-Score were 1,9 [1,9-1,9] % and 8 [8–22] %, respectively. In our clinic, we persuaded the policy of early intervention rather than "watchful waiting" in terms of multiorgan failure in patients with severe tricuspid regurgitation, which is why there were no significant changes in major laboratory parameters before surgery. The mean daily dose of furosemide intake (mg/day) was 40 [40–80]. The majority of patients were highly symptomatic with III-IV NYHA class - 17 (85%). Surgical indications were based on the symptoms of heart failure in 15 (75%) patients, while the rest 5 (25%) had signs of uncontrolled infection despite appropriate antibiotic therapy. Due to prolong preoperative antibiotic medication, only 3 (15%) patients showed positive blood culture samples.
