Beta Blockers, Herceptin, and Training

Hello Drs. Baraki and Feigenbaum,

I hope you both are doing well and are staying healthy. Thanks in advance for all of the tremendously useful content you create for us.

My mother is in remission for breast cancer and has been receiving infusions of Herceptin and Perjeta every three weeks for the past three years. Her recent echocardiograms show a decreased ejection fraction between 50-55% (presumed 2/2 to Herceptin), prompting her cardiologist to place her on a beta blocker.

She asked about the utility of lifestyle modifications for reversing her lowered EF, to which he not only replied that they would be “useless,” but also recommended that she should limit her physical activity to walking and “light weights” for three months.

Can you all see a good reason for such conservative physical activity recommendations?

My mother enjoys hiking and does her best to lift weights when she can, so for the life of me, I can’t understand the sense in her cardiologist’s advice. It seems to grate against the body of evidence you all highlight in your content, not least in your UpToDate article.

She wants to continue staying active but is afraid of going against her doctor’s advice and “damaging her heart.”

Thanks for everything,
Aidan

It’s obviously difficult for us to comment directly on other clinician’s recommendations here.

I would say that within the limitations of the information you’ve provided here, those would not be my recommendations in this situation, and I do not see a clear reason to restrict her physical activity - particularly if she is not symptomatic in any way with activity.

Also for the record, an EF of 50-55% is not considered “reduced” (so I would double check that reported EF measurement; if she does not actually have reduced EF and does not have another clear indication for the beta blocker, I’m not sure why that medication is being recommended either).

Again, these are tricky waters to be navigating via a forum post, so to reiterate the standard disclaimer: this is not intended as specific medical advice for your mother, but is informational in nature only.

Thank you for your reply.

I fully appreciate the limitations of dispensing medical advice over these channels.

My mother does not have hypertension, has no history of heart failure/heart attack/arrhythmia/etc, so I do believe her “borderline” EF is the sole indication for a beta blocker here, in the context of taking Herceptin.

No symptoms other than getting short of breath “more quickly” while hiking.

In any case, she’s interested in a second opinion and will okay go down that road.

Thanks again for your input!

I see.

Yeah, just to reiterate 50-55% is not even “borderline”, and would not be a typical indication for a beta blocker. “Borderline” ejection fraction is defined as 41-49%, “reduced” is < 40%, and “normal” or “preserved” ejection fraction is >50%. I wonder if this concern is based off a decrease from her baseline pre-treatment echocardiogram (perhaps her EF back then was, for example, 65%) – although even in this situation I’d point out that cardiotoxicity from trastuzumab is reversible in the majority of cases with treatment discontinuation.

Anyway, I agree with a second opinion here, and do not see a good reason to restrict her activity (in fact, I see more potential for harm by limiting her to walking alone, which would not be sufficient to meet physical activity guideline minimums).