RIE is less common than left-sided infective endocarditis, usually associated with IVDA and intravascular catheters. The purpose of the study was to analyze the clinical and microbiological characteristics of RIE, particularly tricuspid valve IE (TVIE).Materials and MethodsProspective multicenter study of consecutives cases of definite IE (according to modified Duke criteria) from 48 centers in 13 Argentine provinces were collected between 2013 and 2016.

A total of 502 patients were included; 56 (9.9%) had RIE. Tricuspid valve was affected in 50/56 (49 NV and 1 PV) and was the subgroup analized. Mean age (SD): 61±19,3; male sex 30 (60%). Non-cardiovascular comorbidities: diabetes 32% (end-organ damage 43%), chronic kidney disease 20% (hemodialysis 60%), COPD 16% and history of drug use 8% (half of them referred IVDA). Cardiovascular comorbidities: valvular disease 24% (tricuspid insufficiency 41.66%), CHF 18%. Intracardiac devices 38% (pacemaker 57.8%) and central venous catheters 14%; 45% of patients with pacemakers had concomitant cardiac-device IE. Presumed or confirmed community-aqcuired IE 46%, presumed or confirmed nosocomial IE 50%. Most patients (84%) showed symptoms less than a month before hospitalization; clinical presentation at admission: fever 96%, sepsis 58%, peripheral emboli 52% (pulmonary emboli 84.6%), new heart murmur 28% and acute heart failure 22%. Positive blood cultures 88%: S. aureus 65.9%, Enterococcus faecalis 11.3%, VGS 6.8%, CoNS 6.8%, S. pneumoniae 2.2%, non-identified gram-negative bacilli 2.2% and Candida glabrata 2.2%, polimicrobial 2.2%. Complications: peripheral emboli 42% (85.7% lungs), persistent bacteremia 34%, acute kidney disease 22%, need for supportive care 20%, mechanical ventilation 18% and heart abscess 8%. Surgical treatment was performed in 50% of patients. In-hospital mortality 32%; mortality in patients with medical treatment versus medical and surgical treatment: 10% in both groups.

Since TVIE is frequently associated with intravenous drug use it is noteworthy the lack of cases we found in our series, in relation to the low incidence of IVDA in Argentina. In addition to these findings, our study showed a remarkably high incidence of sepsis on admission as well as a high incidence of acute heart failure and peripheral emboli. These findings support the need for a multidisciplinary approach of RIE.