Table 2.

The prevention, monitoring, and management of cardiac events in patients undergoing cytotoxic chemotherapy^22,25

Treatment phase	Patient profile	Management strategy
Before trastuzumab-based therapy	A. No cardiac history of risk factors with normal EF	Treat and monitor EF every 3 months
	B. Cardiac history and/or risk factors with normal EF	Treat. Ask of symptoms and perform PE before each cycle
	C. Decreased EF	Treat low EF (ACE-I or ARB, BB) and remeasure
		Individual decisions about initiating trastuzumab
During trastuzumab-based therapy	First decrease in EF	Trastuzumab holiday for 1 month
		A. Treat HF and remeasure
		1. Return to baseline. Restart trastuzumab
		2. If EF remains low: intensify HF treatment and remeasure
		3. If EF remains low: individual decisions
	Second decrease in EF	A. Stop trastuzumab
		B. If trastuzumab only option: ‘holiday’ and maximize HF therapy
Completion of trastuzumab-based therapy	No change in EF and no symptoms during treatment	If you have already used anthracyclines is necessary to monitor LVEF at the end of treatment and after 1.2 and 5 years if doxorubicin <200 mg/m2. More strict monitoring if dosage > 200mg/m2. In the case of only trastuzumab, we advice, anyway, follow-up, considering the last results of real-world retrospective studies
	EF decreased or symptoms of heart failure during therapy with trastuzumab	Continue HF treatment. Monitor according to clinical practice for HF. The duration of therapy for HF is variable, if previous anthracyclines may be required for life

The management of cardiac dysfunction before trastuzumab, a major integration to Suter's algorithm (modified from Carver²⁵), is indicated in bold.

The ejection fraction is considered to be reduced when it declines according to Suter's limits (EF < 44, or EF 45–49 and >10 from baseline²⁶). ACE-I, angiotensin-converting enzyme inhibitor; ARB, angiotensin receptor blocker; BB, β-blocker; EF, ejection fraction; HF, heart failure; PE, physical examination.