I. To estimate the cardiotoxicity of a sequential regimen of concurrent weekly paclitaxel and trastuzumab, followed by continued weekly trastuzumab administered concurrently with FEC-75, followed postoperatively by q 3 week trastuzumab for a total duration of trastuzumab therapy through 52 weeks from the first dose (Arm 2), and compare the cardiotoxicity to that of a sequential regimen of FEC-75 alone followed by concurrent weekly paclitaxel and trastuzumab, followed by q 3 week trastuzumab for a total duration of trastuzumab therapy through 52 weeks from the first dose (Arm 1).