Timing of cardiogenic shock and clinical outcomes in takotsubo syndrome: A multicenter cohort study

BACKGROUND Takotsubo syndrome (TTS) may be complicated by cardiogenic shock (CS), a life-threatening condition that worsens prognosis. Whether the timing of CS onset-at admission or during hospitalization-provides prognostic information beyond shock severity remains uncertain. METHODS We conducted a retrospective multicenter cohort study including 1079 consecutive patients with TTS admitted between 2012 and 2024. Patients were classified as having CS at admission, CS developing during hospitalization, or no CS. Shock severity was assessed using the Society for Cardiovascular Angiography and Interventions (SCAI) classification. The primary endpoint was 1-year major adverse cardiac events (MACE), including all-cause death, heart failure events, rehospitalization for arrhythmias, stroke, or myocardial infarction. Kaplan-Meier and multivariable Cox regression evaluated the association between CS timing and outcomes. RESULTS CS occurred in 191 patients (17.7%), including 107 at admission and 84 during hospitalization. In-hospital mortality was higher in patients with CS than in those without CS (13.2% vs 1.6%; p < 0.001). Patients with CS at admission had higher in-hospital mortality and 1-year MACE compared with those who developed CS during hospitalization and those without CS. After adjustment, CS at admission remained an independent predictor of 1-year MACE (HR 2.91, 95% CI 1.54-5.48; p = 0.001), whereas CS developing during hospitalization was not independently associated with long-term outcomes. CONCLUSIONS CS at admission identifies a high-risk TTS phenotype with sustained prognostic impact, whereas CS during hospitalization does not independently influence long-term outcomes. Integrating CS timing into early assessment may improve risk stratification and guide monitoring and escalation strategies in acute TTS.