RESUMEN
Background: Takotsubo syndrome (TTS) is characterized by transient regional left ventricular (LV) dysfunction occurring in individuals exposed to physical or emotional stress. Various stressors are triggers for TTS in cancer patients, and anti-cancer drugs have recently been proposed as a trigger. Therefore, further studies are needed to clarify these triggers and avoid the unnecessary interruption of anti-cancer treatment. Case summary: A 66-year-old woman presented with dyspnoea 10 days after the initiation of atezolizumab in combination with bevacizumab. She had previously received osimertinib as first-line therapy for recurrent lung cancer after primary resection and atezolizumab in combination with bevacizumab, paclitaxel, and carboplatin as second-line therapy. She was admitted due to electrocardiography abnormalities and elevated troponin I and brain natriuretic peptide levels. Echocardiography revealed circumferential severe LV hypokinesis at the mid-ventricular level, with preserved wall motion at the base and apex. Cardiac catheterization performed after the attenuation of symptoms with 20 mg of intravenous furosemide showed normal coronary arteries. Cardiac magnetic resonance imaging on Day 4 revealed increases in T1 and T2 values and extracellular volume fraction; however, neither myocardial infiltration of inflammatory cells or myocardial necrosis was observed in endomyocardial samples obtained on the day of her arrival. Atypical TTS was suspected, and she was treated with perindopril, bisoprolol, and spironolactone. Magnetic resonance imaging 1.5 months after the onset of TTS showed improvements in LV contractility, T1 and T2 values, and the extracellular volume fraction. Discussion: A more detailed understanding of the relationship between anti-cancer drugs and TTS is crucial for preventing interruptions to anti-cancer therapy.