Impact of Admission Hyperglycemia on Heart Failure Events and Mortality in Patients With Takotsubo Syndrome at Long-term Follow-up: Data From HIGH-GLUCOTAKO Investigators

OBJECTIVE: To investigate admission hyperglycemia effects on the sympathetic system and long-term prognosis in Takotsubo syndrome (TTS). RESEARCH DESIGN AND METHODS: In patients with TTS and hyperglycemia (n = 28) versus normoglycemia (n = 48), serum norepinephrine and 123I-labeled metaiodobenzylguanidine (MIBG) cardiac scintigraphy were assessed. Heart failure (HF) occurrence and death events over 2 years were evaluated. RESULTS: At hospitalization, those with hyperglycemia versus normoglycemia had higher levels of inflammatory markers and B-type natriuretic peptide and lower left ventricular ejection fraction. Glucose values correlated with norepinephrine levels (R2 = 0.39; P = 0.001). In 30 patients with TTS, 123I-MIBG cardiac scintigraphy showed lower late heart-to-mediastinum ratio values in the acute phase (P < 0.001) and at follow-up (P < 0.001) in those with hyperglycemia. Patients with hyperglycemia had higher rates of HF (P < 0.001) and death events (P < 0.05) after 24 months. In multivariate Cox regression analysis, hyperglycemia (P = 0.008), tumor necrosis factor-α (P = 0.001), and norepinephrine (P = 0.035) were independent predictors of HF events. CONCLUSIONS: Patients with TTS and hyperglycemia exhibit sympathetic overactivity with a hyperglycemia-mediated proinflammatory pathway, which could cause worse prognosis during follow-up.