Associations Between Acute Heat Exposure and Hospitalization for Takotsubo Syndrome in the State of California, 2006 to 2019

Journal of the American Heart Association, Volume 15, Issue 11 , June 2, 2026. BackgroundTakotsubo Syndrome (TTS), a transient cardiac condition often triggered by physical or emotional stress, may be sensitive to extreme environmental exposures.

Although psychosocial factors are well‐established triggers, limited evidence exists on the role of temperature extremes, particularly heat waves, in precipitating TTS events. We investigated the association between short‐term heat wave exposure and TTS hospitalizations in California.MethodsWe conducted a time‐stratified case‐crossover analysis using statewide emergency department and hospitalization data from California (2006–2019).

TTS hospitalizations were identified based onInternational Classification of Diseases, Ninth Revision, Clinical Modification(ICD‐9‐CM) code 429.83 andICD‐10‐CMcode I51.81, using 4 case definitions incorporating primary versus secondary diagnosis and procedural criteria. Heatwaves were defined as ≥2 consecutive days exceeding the ZIP code‐specific 95th percentile of daily maximum temperature.

Conditional logistic regression models were used to estimate odds ratios (ORs) and 95% CIs, adjusting for dew point temperature, day of year, and holidays.ResultsWe identified 5018 TTS hospitalization events.