Supplementary Material for: Different Clinical Features between Definite and Possible Takotsubo Syndrome in a Tertiary Referral Hospital

Background: Although imaging examination to exclude coronary artery disease (CAD) is an indispensable step for a definite diagnosis of Takotsubo syndrome (TTS), this step may be overlooked in a substantial proportion of patients with secondary TTS admitted to a tertiary hospital. However, the clinical profiles and outcomes of these patients with “possible TTS” have rarely been investigated. Methods: Among 420 consecutive TTS patients with characteristic transient ventricular ballooning on repeated echocardiography, 244 patients (58.1%) who underwent an imaging study for CAD were diagnosed with “definite TTS”, whereas the remaining 176 were designated with “possible TTS”. Results: Overall, hypoxia (67.6%) and dyspnea (55.5%) were predominant presentations. The possible group was characterized by higher prevalence of male gender (46.6% vs. 35.2%, p = 0.019), secondary TTS (97.2% vs. 86.5%, p <0.001), cancer (43.2% vs. 29.1%, p = 0.003), sepsis (46.0% vs. 32.0%, p = 0.003), and non-apical ballooning pattern (30.7% vs. 21.3%, p = 0.001) with less common ST-segment elevation on electrocardiogram (18.8% vs. 34.0%, p = 0.001). The possible group showed higher frequency of mechanical ventilation (56.2% vs. 40.2%, p = 0.001), pulmonary edema (72.2% vs. 61.5%, p = 0.023) and shock management (70.5% vs. 54.1%, p = 0.001) with similar in-hospital mortality (17.2% vs. 17.0%, p = 0.964). Conclusions: In real-world clinical practice, coronary evaluation for strict diagnosis of TTS is not frequently feasible. Addition of the possible group without coronary evaluation to the clinical spectrum of TTS would be helpful for fair estimation of clinical implication of TTS.