Biventricular Takotsubo vs  Myocarditis – a diagnostic challenge

Background: Takotsubo cardiomyopathy (TCM) is an important differential diagnosis of acute coronary syndrome and myocarditis. It is characterized by normal or near-normal coronary arteries and regional wall motion abnormalities that extend beyond a single coronary vascular bed. Variants of the classical left ventricular (LV) apical ballooning are increasing in recognition as cardiac magnetic resonance (CMR) is more extensively used. Case report: We present a case of 69-year-old woman with a previous history of hypertension, diabetes and dyslipidaemia, transferred to our emergency department due to suspected acute coronary syndrome. She had a history of two episodes of an oppressive chest pain longer than 1 hour, orthopnoea and paroxysmal nocturnal dyspnoea 36 hours before. Two weeks before she had had a lower tract respiratory infection, that was not totally resolved. On admission, she only had dyspnoea. On examination, she had wheezing, arrhythmic pulse and hypertension. Breath sounds were absent in lower chest and rales were also noted. Electrocardiogram showed rapid atrial fibrillation, poor R wave progression in anteroseptal leads and inverted T waves in I, aVL and V2-V6 leads. Modest elevation in cardiac troponin (4.55 ng/mL) was observed. Chest x-ray showed bilateral pleural effusion. A transthoracic echocardiography (TTE) was immediately performed and revealed akinesis/dyskinesis of mid to apical segments (apical ballooning) of both ventricles, extended beyond a single epicardial coronary distribution, compatible with biventricular TCM. Cardiac catheterization showed absence of obstructive coronary disease. A CMR, performed two days later, showed moderate biventricular systolic dysfunction, hypokinesis in mid to apical segments of LV and hypokinesis in apical right ventricle. It also showed non-ischemic late gadolinium enhancement in antero-apical and lateral apical segments. After several days of medical management, the patient was discharged from the hospital in stable condition. TTE performed 6-month after evidenced complete biventricular function recovery and no segmental contractility changes. CMR supported the functional recovery and the resolution of contractility abnormalities, but noticed the intramyocardial late gadolinium enhancement in the segments previously reported. Conclusion: There are fewer reports of this unusual presentation of TCM, described by ETT. This case represents a good example of the diagnostic challenge between myocarditis and takotsubo cardiomyopathy. Taking in account the exuberance of the case, the mild elevation of troponin, the full recovery of biventricular function and resolution of contractility abnormalities, it seems more probably to be a TCM, in a patient who, probably had a previous scar of myocarditis. Although, the hypothesis of acute myocarditis as the primary diagnosis cannot be excluded.