Characteristics and outcomes of patients with right-sided endocarditis undergoing cardiac surgery

Background: There has been an increasing incidence of right-sided infective endocarditis (RSIE) due to the global rise of intravenous drug use (IVDU) and an increasing number of implantable cardiac electronic devices and central venous catheters. Our aim was to investigate differences in the clinical presentation, microbiological findings and prognosis of patients undergoing surgery for RSIE compared to left-sided infective endocarditis (LSIE).
Methods: Relevant clinical data of all 432 consecutive patients undergoing valve surgery for infective endocarditis (IE) at our institution between January 2009 and December 2018 were retrospectively analyzed. Acquired data included patients’ demographic and preoperative comorbidities, manifestation of IE according to the recently modified Duke Criteria, perioperative data and relevant clinical outcomes.
Results: A total of 403 patients (93.3%) underwent surgery for LSIE and twenty-nine patients (6.7%) for RSIE. Eleven patients with RSIE (37.9%) showed a concomitant left-sided infection. Compared to LSIE, RSIE patients were significantly younger [47.5 (40.4–69.3) vs. 65.1 (53.7–74.6); P=0.008] and presented with less comorbidities such as hypertension (41.4% vs. 65.3%; P=0.010) and coronary artery disease (6.9% vs. 29.0%; P=0.010). Rates of IVDU (34.5% vs. 4.5%; P<0.001), human immunodeficiency virus (HIV) (10.3% vs. 1.7%; P=0.023) and hepatitis C virus (HCV) infection (24.1% vs. 5.2%; P=0.001) were greater in RSIE. The proportion of Staphylococcus aureus IE was significantly higher in RSIE compared to LSIE (37.9% vs. 21.1%; P=0.035). 30-day mortality was 6.9% after surgery for RSIE compared to 14.6% after operation for LSIE (P=0.372).
Conclusions: Patients undergoing surgery for RSIE compared to LSIE presented with a higher rate of pulmonary septic emboli, more Staphylococcus aureus infections and larger vegetations. Larger multicenter prospective trials are needed to provide more reliable data on the clinical profile of these patients, in order to determine optimal surgical management.