Observed Clinical, Laboratory, and Echocardiographic Parameters in Takotsubo Syndrome Patients with Mortality and Decreased Ejection Fraction During Initial Hospital Admission

Abstract

CONTEXT Approximately 1-2% of patients with suspected acute coronary syndrome also develop Takotsubo syndrome (TTS). This syndrome is characterized by transient systolic dysfunction of the apical and/or mid segments of the left ventricle that mimics myocardial infarction in the absence of obstructive coronary artery disease. Up to 21.8% of TTS patients develop serious complications, including death. Currently, there is no consensus on management of these patients and their complications. Thus, identifying TTS patients at higher risk for complications becomes valuable in managing their hospital course. The aim of this study was to examine the predictive significance of laboratory, echocardiographic, and clinical parameters on in-hospital mortality in a sample subgroup of TTS patients. Secondary analyses were performed on patients with reduced (i.e., <35%) ejection fractions. METHODS This retrospective study at a community hospital identified patients from October 1, 2009 to August 31, 2015 who presented with ACS and underwent cardiac catheterization. Patients were diagnosed with TTS by features of cardiomyopathy on cardiac catheterization or echocardiogram. RESULTS The authors analyzed data from a total of 177 eligible patients identified with TTS. The in-hospital mortality rate was 5.65%. Compared to the non-mortality subgroup, patients who suffered in-hospital mortality had significantly lower diastolic blood pressure on admission (p < 0.050), lower hemoglobin levels (p < 0.001), lower sodium (p = 0.020), higher blood urea nitrogen (p = 0.009), lower glomerular filtration rate (p = 0.016), and lower albumin levels (p < 0.001). Cox regression analyses demonstrated admission hemoglobin was significant, yielding a mortality hazard ratio of 0.760 (95% CI of 0.594-0.972, p = 0.029). CONCLUSIONS Patients who present with TTS and hypotension, anemia, low albumin levels, elevated lactic acid and renal dysfunction were associated with higher rates of in-hospital mortality in this study's sample population. Further, admission hemoglobin had the strongest association with death. Every unit decrease in hemoglobin increased mortality risk by 24%.