Mike I had bacterial endocarditis and it took 8 months until it was diagnosed. There are two types of endocarditis Acute and Sub Acute. Acute sets in very quickly a persons health collapses within a few days. Sub Acute can take weeks of months to build up and its symptoms can be vague like a bad cold or flu. I started with what felt like a sinus infection and a bit of bronchitis, like a bad cold. It wouldn't go after about 6 weeks I started to develop joint pain like arthritis. I went on antibiotics and things improved significantly, close to back to normal however after a couple of weeks the symptoms would return. The oral antibiotics kill the infection in the rest of the body but not in the heart, after they are discontinued the infection spreads to the rest of the body again. This is why endocarditis can be difficult to find from blood cultures if you have recently been taking antibiotics. I had my first lot of blood test 3 months before it was discovered. My cycle of antibiotics and relapses continued I would get worse each time I would perspire profusely at the slightest exertion and I would have night sweats which had to be seen to be believed and developed a bad cough that would go when I was on the antibiotics. I would develop a low grade fever however it never went over 38.5C. I did however have a loss of appertite and did have some weight loss. Because my valve hadn't completely been destroyed the surgeon wanted the endocarditis treated before he would operate. When they did operate not only was the valve damaged I had the most severe form of complication with endocarditis, 2 abscesses inside my heart.
Unlike Sue I had no splinter haemorrhages or Janeway lesions and didn't vomit.
Native valves can be saved if treatment is early before the valve is damaged or has vegetations. I am not sure if prosthetic valves can be saved.