Have any of you had Bostons with congestive heart failure ?

Sassy ( in the past week ) has peed herself twice . Both times she has done it in her sleep , and doesent even seem to know she has done it . The first time I thought it was a fluke , and cleaned up the mess figuring it was my fault for not letting her out enough . She did it again last night , and I woke her up beacuse she was laying in the puddle snoring away , and still did not even notice ( I did , it was on our bed this time !) . Does this happen to dogs with CHF was was just never brought up by her vet ? I only ask here beacuse it is a holiday , so the vet is closed. :/