Carvedilol for the Prevention of Anthracycline/Anti-HER2 Therapy Associated Cardiotoxicity Among Women With HER2-Positive Breast Cancer Using Myocardial Strain Imaging for Early Risk Stratification

Inclusion Criteria:

* Female
* Age ≥ 18 years
* Non-metastatic histologically confirmed primary invasive breast carcinoma
* Pathologically confirmed HER2-positive breast cancer
* Scheduled to receive anthracycline chemotherapy followed by anti-HER2 therapy at MSKCC
* Able and willing to provide informed consent
* Willing and able to comply with the requirements of the protocol
* Able to swallow capsules

For Aim 2, all patients must meet the following criteria:

* Meet all inclusion criteria above

  * LVEF \> 50%
* Abnormal global longitudinal strain (\<19%, or a % decrease of ≥ 11% from baseline) prior to initiation of planned anti-HER2 therapy
* Heart rate ≥ 50 beats per minute
* Sitting systolic blood pressure \> 90 mmHg

Exclusion Criteria:

* Patients are to be excluded from randomization for Aim 2 of this study if they meet any of the following criteria:
* Current treatment with ACE-inhibitors or beta blockers
* Allergies or inability to tolerate beta blockers previously due to bradycardia, hypotension, or AV block.
* Known history of NCI CTCAE (Version 4.0) Grade ≥ 2 symptomatic CHF, myocardial infarction within 12 months prior to randomization, significant symptoms (Grade ≥ 3) relating to left ventricular dysfunction, significant (moderate or severe) valvular disease, or significant cardiac arrhythmia (Grade ≥ 3)
* Pre-menopausal women without a negative serum or urine pregnancy test within 4 weeks of starting treatment
* Enrollment in a therapeutic intervention trial in the Breast Medicine service