Are there cases where strep throat cause immune system to attack heart but it is very mild to be considered rheumatic fever?

Doubtful. If you have confirmed strep throat, the treatment of amoxicillin or azithromycin would protect from rheumatic fever, scarlet fever, etc. There are other conditions that can cause systemic symptoms of fever and shortness of breath (Lemierre's syndrome). If the process was a viral syndrome e.g mononucleosis (which can cause an exudative tonsillitis) the fatigue, sweats would persist. See a doctor.

Related Questions

Before strep throat reaches level of rheumatic fever, do immune system already mildly attack body tissues?

Clarification. First, not all will develop rheumatic fever if untreated.The frequency is estimated at 1/200 untreated cases & what makes some do it and others not is unknown. Second, for those that will have 10 days to start treatment during which you can stop auto-antibodies to human tissue from forming. They would form antibodies to strep, just not auto-antibodies. Read more...

Is it possible for strep throat which caused extremely mild rheumatic fever to go away on its own after taking 4 tablets of clarithromycin?

If you have. rheumatic fever /strep it is important to take the full course of prescribed antibiotics. You have written in quite a few times about this - so clearly you are worried. Did you self -medicate with the clarithromycin? Read more...