**3. Natural history**

Isolated TVE has been reported to have a favorable prognosis and good response to medical therapy with few exceptions. Ginzton and colleagues studied 16 patients (12 had history of IVDA) with TVE to define echocardiographic criteria to help identifying those at risk for complications or need for TV surgery [8]. The authors concluded that TV vegetations tend to resolve with time, however, those with persistent infection, cardiomegaly and right heart failure are at increased risk, and no M mode or two-dimensional echocardiographic feature is a predictor of outcome.

This tendency for TV vegetations to resolve overtime is different from left-sided endocarditis which tend to persist. This could be related to bacteriological cure or silent embolization to the lung overtime.
