My Wife Is 38 Years Old And Rheumatic Heart Disease

My wife is 38 years old and Rheumatic Heart disease patient. She has undergone Balloon valvoplasty for dilation of her Mitral valve in 1999. She has had regular check-ups annually. In November/2012, she had suffered stroke and got paralyzed in the right side of the body. In July/2014, she had again undergone Balloon valvoplasty for dilation of her Mitral valve. She is almost normal now. She undergoes regular check-ups annually for Heart problem. As per advice of treating doctor, she is taking the following drugs:-
(i)     Acitrom 2 mg - 5 times weekly
(ii)     Acitrom 1 mg - 2 times weekly
(iii)     Digoxin 0.25 mg – ½ tablets daily
(iv)     Calaptin 40 mg – 5 tablets daily (2-2-1)
(v)     Injection Penidure 12 lac - After 21 days

She has been suffering from the problem of frequent and uncontrollable urination since last 1 and 1/2 years. She has to go for urination several times a day and has got uncontrollable urge for urination. Six months ago, her creatinine level was found to be 1 during a regular blood test. Earlier, she used to take diuretic like Amifru but is not taking this drug for more than one year.
Kindly advise what could be the reason for this urination problem. Also advise what could be the possible treatment for this problem.