If you are being treated for heart failure, there are medications associated with heart failure that include blood pressure medication and lipid lowering meds, etc. but there is no direct causal effect from heart failure only the possible result from treatment. .
I wouldnt have thought so, voice problems are more associated with vocal chord problems or the ability to pass air over them correctly, through lung deficiency for example. If heart failure is causing shortness of breath, then this will obviously have
an effect.