Admission heart rate and in-hospital course of patients with Takotsubo syndrome

Abstract

Background: In-hospital course of patients with Takotsubo syndrome (TS) is quite heterogeneous and life-threatening complications are not uncommon in the acute phase. The role of heart rate (HR) as a predictor of prognosis has not been sufficiently investigated in this setting. The study aims to assess the impact of HR at presentation on in-hospital course of patients with TS.

Methods: The study population included 221 patients with TS enrolled in a multicentric registry. HR at admission was evaluated on the first electrocardiogram. According to tertile distribution of HR at presentation, 3 groups were identified: Group A (HR ≤ 76 beats per minute (bpm), n = 76), Group B (HR 77-95 bpm, n = 74) and Group C (HR > 95 bpm, n = 71). Acute in-hospital complications were defined as occurrence of severe pump failure and major arrhythmias.

Results: 32 (14.4%) patients experienced complicated in-hospital course. HR on admission was significantly higher (108 bpm vs. 85 bpm; p < 0.001) and ejection fraction (EF) lower (35% vs. 40%; p = 0.009) in patients with complications than in those without. Patients in Group C experienced a 5-fold higher rate of complications compared to group A and B. After multivariate analysis, higher HR (odds ratio 1.34 per 10 bpm increase, 95% confidence interval (CI) 1.12-1.59; p = 0.001) and lower EF (odds ratio 1.24 per 5% decrease, 95% CI 1.01-1.54; p = 0.049) remained independently associated with a worse outcome.

Conclusion: In a large population with TS, high HR on admission independently predicted complicated in-hospital course.

Keywords: Acute pulmonary oedema; Heart rate; Prognosis; Shock; Takotsubo syndrome.