A 47-year-old woman with HER2-positive early breast cancer is started on adjuvant trastuzumab with a baseline left ventricular ejection fraction of 62%. Which monitoring strategy is appropriate during therapy?

• A Weekly serum troponin measurement throughout therapy
• B Serial assessment of LVEF by echocardiography or MUGA scan during treatment ✓
• C Coronary angiography before each trastuzumab cycle
• D Monthly electrocardiography as the sole surveillance tool

Explanation

Trastuzumab inhibits HER2 signalling in cardiac myocytes and can produce a decline in LVEF, usually without irreversible myocyte death, so periodic echocardiographic or MUGA surveillance is standard. Trastuzumab is held for symptomatic heart failure or a significant asymptomatic LVEF fall. Troponins and angiography are not routine, and an ECG cannot detect the ventricular dysfunction that defines this toxicity.

Reference: Katzung's Basic and Clinical Pharmacology, 15th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

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