Prognosis

Prognosis varies widely depending on a number of factors. (1) Predictors of poor outcome include;

Patient characteristics: older age, prosthetic valve IE, diabetes, comorbidity (eg, frailty, immunosuppression, renal or pulmonary disease).

Clinical complications such as heart or renal failure, brain haemorrhage, septic shock.

Micro-organism: S. aureus, fungi, non-HACEK Gram-negative bacilli.

Echocardiogram findings: peri-annular complications, severe left-sided valve regurgitation, low left ventricular ejection fraction, pulmonary hypertension, large vegetations, severe prosthetic valve dysfunction, premature mitral valve closure and other signs of elevated diastolic pressures.

• The overall mortality rate remains at 30% (2) with subsets including:
• S. viridans 4-16% mortality
• S. aureus 25-47% mortality
• fungal infections - over 50% mortality
• right-sided endocarditis in IV drug abusers - about 10% mortality

For infective endocarditis following prosthetic valve replacement, early endocarditis 30-70% mortality and late endocarditis 20-30% mortality.

Increased mortality rates are associated with increased age, infection involving the aortic valve, development of congestive heart failure, central nervous system complications and underlying disease.

References:

1. European Society of Cardiology (Aug 2023). 2023 ESC Guidelines for the management of infective endocarditis.

2. Cahill TJ, Prendergast BD. Infective endocarditis. Lancet. 2015 September.