It appears that your wife has rheumatic heart disease with only minimal affliction of the heart valves. The arthritis seems to be a part of rheumatic process. Sore throat (streptococcal throat infection) is the most acceptable cause of this complex process. Penicillin is the best preventive measure to prevent recurrences of rheumatic fever. A long acting shot once in 3 weeks is the preventive strategy. It is simple and she can take a tablet of paracetamol after the injection to make the injection more acceptable. Recurrences can lead to damage of the heart valve and a mild lesion can become severe, which should not be allowed to happen. It is also advisable to repeat an echocardiography once in a year. This is a good way of monitoring the heart valve performance.