Endocarditis and its effects on mitral valve
Before the discovery of antibiotics, infective endocarditis was invariably fatal. Even with advancements in diagnosis and treatment, the in-hospital mortality rate for infective endocarditis is still high at 20% to 25%.22 Studies have shown that early and late mortality rates were lower and event-free survival was greater in patients who went through mitral valve repair to treat acute endocarditis, as compared to those who underwent mitral valve replacement.23 There is also a lower incidence of recurrent infections associated with mitral valve repair as compared to mitral valve replacement.24 Therefore, patients with mitral valve endocarditis should be offered mitral valve repair whenever possible.23 89% of endocarditis patients who underwent mitral valve surgery are free from re-surgery at 5 years. This value decreases to 72% at 10 years post-operation. Patients who received mechanical valve replacements have a higher or equal rate of freedom from re-operation at 10 years compared with those who received biological valve replacements.25 Native mitral valve endocarditis is relatively responsive to antibiotic treatment, therefore is likely to be cured pharmacologically. Prosthetic mitral valve endocarditis is, however, linked with poorer prognosis.26