SABE i.e. Sub Acute Bacterial Endocarditis is usually caused by a form of streptococci viridans bacteria that normally live in the mouth and throat (Streptococcus mutans, mitis, sanguis or milleri). Other strains of streptococci (bovis and equines) can also cause subacute endocarditis, usually in patients who have a form of gastrointestinal cancer.
Underlying structural valve disease is usually present in patients before developing subacute endocarditis. It is less likely to lead to septic emboli than is acute endocarditis, but subacute endocarditis has a relatively slow process of infection and, if left untreated, can worsen for up to one year before it is fatal.
In cases of subacute bacterial endocarditis, the causative organism(streptococcus viridans) needs a previous heart valve disease to colonize and cause such disease.
On the other hand, in cases of acute bacterial endocarditis, the organism can colonize on the healthy heart valve, causing the disease.
Hence it is essential that a patient with h/o a valvular defect should be attended to for complete oral health care as a preventive measure to avoid SABE