Heart function dramatically reduced by Herceptin

[jpuk]

Has anyone else experienced a significant downturn in cardiac function as a result of Herceptin treatment? I have been on Herceptin for 3 months. My firsst The MUGA test before starting chemo in January showed a respectable 67%; the test before starting Herceptin in August showed 61%, i.e a 10% loss presumably caused by the chemo. Now today I have learned that the MUGA test done 2 days ago showed only 52% - a further 15% reduction in the 3 months on Herceptin, and only just above the 50% safety tolerance level. My oncologist has decided I can have the treatment tomorrow but must repeat the MUGA test in 3 weeks, and if the resullt is similar or worse the treatment wil be stopped.

My diagnosis last December was Inflammatory Breast Cancer, plus 3 tumours and DCIS and IDC, and massively HER2 positive (5/13 nodes positive although mercifully no further invasion detected) - so the likely prospect of having Herceptin withdrawn is sickening - like a lifeline about to be taken away.

Does anyone have a similar experience? If so, what has subsequently transpired?