1 Year of Herceptin Best for Lowering Recurrence Risk

Hi, I am diagnosed with Stage 1a, HER+ BC.  I did the 12 Taxol treatments.  One month since last one and am now on the Herceptin for a year.  Which I get every three weeks.  I've heard good things about Herceptin, but also some bad.  I've been told by my Ocologist that heart damage risk is rare, and the nurse also reassured me this.  Yet I've read on here some women have gotten permanent heart valve damage from it.  This has me scared now.  My BC was taken out... with left side mastectomy.  Besides all this, I am in excellent health.  I'm 55 years old.  I told my Ocologist that for me to do the Adjuvant Taxol and Herceptin I'd have to stay in good health.  There is no point for me to end up disable with a bad heart etc., as my Oncotype was low to start with.  I sometimes wish I hadn't done this at all.  Because it was low anyways. 

So, my question is, should I be overly concerned about taking this Herceptin?  I've had two echocardiograms and they were good.  I'm due for another one in a few months.  Does the echocardiogram catch valve problems etc?  Should I just get off this drug?

Wabals, thank you for your reply.  I am glad you are doing well.  How long have you been finished your chemo and Herceptin?  What chemo drug did you do?  Was it the weekly one?  What I've read on here is in some women 10 years later they ended up with CHF and the cardiologist said it was probably from the chemo?  I am seeing a cardiologist in about 2 weeks.  Going to be doing a 24 hour Holter Monitor and then talk with him when the results are in.  I have heart palpitations, but I had them before all this started too.  So, gonna have it checked anyways.  I feel funny on the Herceptin, with the heart palpitations and I have a dry cough occasionally with fatique.  The fatique is only usually a day or two after the treatment.  I get anxious sometimes, usually at night, when I'm laying down.  The heart palpitations don't help the matter, although I as stated my echocardiograms appear to be fine.  I hope it's all normal and not anything to worry about.  I just worry 10  years (less or more) down the road I end up with serious issues from these drugs?  There is a discussion board on here with a lot of women this seems to have happened to.