Infective Endocarditis-Characteristics and Prognosis According to the Affected Valves

Infective endocarditis (IE) continues to be a disease with high mortality despite medical advances.

The objective of this study was to investigate the characteristics and prognosis of IE according to the affected valves.

This study was retrospective and single-centered, and it included 270 patients with a diagnosis of IE, for the period 2005-2021, who received treatment at the University Hospital "St. Georgi" in Plovdiv, Bulgaria.

Single-valve IE (SIE) was found in 82.6% (n-223), multivalvular IE (MIE) in 16.66% (n = 45) and device IE (CDRIE) in 0.74% (n = 2) of patients. The most commonly affected valve was the aortic valve, in 44.8% (n = 121). The predominant multivalvular involvement was aortic-mitral valves (AV-MV) (13.7%, n = 37). The patients with tricuspid valve (TV) IE were significantly younger, at 39 (30) years, and were more frequently male (80.8%). Mortality was higher in MIE than in SIE (31.1% vs. 23.8%) and was the highest in multivalve aortic-tricuspid (AV-TV) IE (75%). Early surgery was performed most in AV-MV IE, in 29.7% (n = 11). The Charlson comorbidity index (CCI) was significantly higher in MV 4 (4) and AV 3 (3) vs. TV IE 1 (5) (p = 0.048 and p = 0.011, respectively). Septic shock occurred most frequently in AV-TV involvement (75%; p = 0.0001). The most common causative agents were of the Staphylococcus group. Staphylococcus aureus more often affected TV alone (46.2%, n = 124) vs. AV (9.9%, n = 14; p = 0.0001) and vs. MV (22.6%, n = 17; p = 0.022); Staphylococcus coagulase-negative (CNG) was the prevalent cause of MV IE (22.7%, n = 17) vs. AV-MV (2.7%, n = 1; p = 0.007). Streptococci were represented in a low percentage and only in left-sided IE, more frequently in AV-MV (18.9%, n = 7) vs. AV (6.6%, n = 8; p = 0.025).

The aortic valve is the most frequently affected valve, as single-valve IE or as multivalve AV-MV, with the predominant causative agents being of the Staphylococcus group. AV-TV IE has the worst prognosis, with the most common complication of septic shock and the highest in-hospital mortality.