Prognostic Utility of Society for Cardiovascular Angiography and Interventions Shock Stage Approach for Classifying Cardiogenic Shock Severity in Takotsubo Syndrome

Abstract

Background Cardiogenic shock (CS) is a significant complication of Takotsubo syndrome (TTS), contributing to heightened mortality and morbidity. Despite this, the Society for Cardiovascular Angiography and Interventions (SCAI) staging system for CS severity lacks validation in patients with TTS and CS. This study aimed to characterize a patient cohort with TTS using the SCAI staging system and assess its utility in cases of TTS complicated by CS. Methods and Results From a TTS national registry, 1591 consecutive patients were initially enrolled and stratified into 5 SCAI stages (A through E). Primary outcome was all‐cause in‐hospital mortality; secondary end points were TTS‐related in‐hospital complications and 1‐year all‐cause mortality. After exclusions, the final cohort comprised 1163 patients, mean age 71.0±11.8 years, and 87% were female. Patients were categorized across SCAI shock stages as follows: A 72.1%, B 12.2%, C 11.2%, D 2.7%, and E 1.8%. Significant variations in baseline demographics, comorbidities, clinical presentations, and in‐hospital courses were observed across SCAI shock stages. After multivariable adjustment, each higher SCAI shock stage showed a significant association with increased in‐hospital mortality (adjusted odds ratio: 1.77–29.31) compared with SCAI shock stage A. Higher SCAI shock stages were also associated with increased 1‐year mortality. Conclusions In a large multicenter patient cohort with TTS, the functional SCAI shock stage classification effectively stratified mortality risk, revealing a continuum of escalating shock severity with higher stages correlating with increased in‐hospital mortality. This study highlights the applicability and prognostic value of the SCAI staging system in TTS‐related CS.