Case Report:
A 48-year-old woman was diagnosed with right sided Grade 2 invasive
breast carcinoma (no special type (NST), oestrogen receptor/
progesterone receptor (ER/PR) negative and human epidermal growth factor
receptor 2 (HER2) positive), in April 2021. She had received adjuvant
chemotherapy with four cycles of anthracycline, twelve cycles of
Paclitaxel, and two cycles of Trastuzamab chemotherapies, to be followed
by bilateral mastectomy and adjuvant radiation and on-going Trastuzumab.
Prior to the initiation of chemotherapy, a transthoracic echocardiogram
(TTE) demonstrated normal left ventricular (LV) systolic function, with
LV ejection fraction (LVEF) of 64% with a global longitudinal strain
(GLS) of -21% (Figure 1, A). She had routine cardiac surveillance as is
clinical practice at our centre with a repeat TTE (August 2021) after
anthracycline therapy and prior to commencement of Trastuzamab (Figure
1, B). This demonstrated LVEF of 59% with GLS of -19% (9% relative
reduction in GLS compared to baseline). As is standard of care, a TTE is
performed at 3 monthly intervals after commencement of Trastuzumab. Her
next routine 3 monthly TTE (November 2021) demonstrated a further
reduction in LVEF to 56% and GLS of -18% (14% relative reduction
compared to baseline (TTE measurements were repeated by an experienced
and independent sonographer and verified by the consulting
cardiologist), triggering review by a cardiologist (Figure 1, C). There
was no significant change in blood pressure, heart rate, LV volumes, LA
volume or E/eā over this period.
At cardiologist review, the patient reported no cardiovascular symptoms,
in particular no dyspnoea, fatigue, or pedal oedema. She mentioned that
she had COVID-19 infection (although having been vaccinated prior (x 2
doses) in late September 2021 and had mild ā moderate symptoms of
dyspnoea and fatigue for approximately three weeks, though she denied
any chest pain or palpitations., she did not have any blood tests (for
cardiac biomarkers), require hospitalisation, and did not receive
specific antiviral therapy. On examination, she had a heart rate of 60
bpm, was normotensive with a blood pressure of 124/78 mmHg, with normal
heart sounds, no murmurs or rubs. Electrocardiogram showed sinus rhythm
with normal axis, and non-specific T wave inversion in leads III and
aVF.
The patient had an asymptomatic drop in LVEF of 9% and 14% relative
reduction in LV GLS compared with her baseline study whilst on
Trastuzumab, and therefore met criteria for commencement of
cardioprotective therapy (angiotensin-converting enzyme inhibitor +/-
Beta blocker therapy). However, given the history of COVID infection in
the interim with resolution of symptoms subsequently, a decision was
made to continue with Trastuzumab therapy with TTE surveillance after
further two cycles of Trastuzamab, without initiation of
cardioprotective therapy.
At follow up, the patient reported no further symptoms and did not have
dyspnoea or fatigue. Her TTE in January 2022 demonstrated improved LVEF
of 59% and GLS of -19% (Figure 1, D). She has subsequently continued
Trastuzumab with standard clinical surveillance, without commencement of
cardioprotective agents.