Transient left atrial dysfunction is a feature of Takotsubo syndrome

Background: Takotsubo syndrome (TTS) is characterized by a transient left and/or right ventricular dysfunction as a consequence of a distinctive pattern of regional wall motion abnormalities. However, a systematic evaluation of the left atrial (LA) function in patients with TTS is lacking. The aim of the present study was therefore to comprehensively assess LA performance indexes and function in patients with TTS. Methods: We compared LA function assessed by volumetric indexes derived from fractional volume changes in cardiovascular magnetic resonance (CMR) between 125 TTS patients and 125 patients with anterior ST-segment elevation myocardial infarction (STEMI). Furthermore, recovery of LA performance was evaluated in a subgroup of 20 TTS patients with follow-up CMR data. Results: Patients with TTS demonstrated a significantly lower total LA emptying fraction (EF) [44% (interquartile range (IQR) 34-53%) versus 51% (IQR 42-56%); p < 0.01], passive LA-EF [21% (IQR 14-30%) versus 24% (IQR 20-29%); p = 0.03] and active LA-EF [29% (IQR 20-38%) versus 35% (28-42%); p < 0.01] compared to patients with anterior STEMI. Among the 20 TTS patients with serial CMR data, the total LA-EF significantly improved from 42% (IQR 29-48%) at the acute stage to 51% (IQR 46-59%) at follow-up (p < 0.01). Similarly, active LA-EF (p < 0.01) and passive LA-EF (p = 0.02) improved significantly as well. Conclusion: Compared to anterior STEMI, TTS patients demonstrated a significantly decreased LA function during the acute/subacute phase of the disease. However, impairment of LA performance seems to be transient in TTS with recovery during follow-up.