A new technology identifies emergency department patients with acute heart failure at a low risk for 30-day adverse events who may be applicable for safe hospital discharge, according to research published in the Journal of the American College of Cardiology: Heart Failure.
More than 80% of visits to the emergency department (ED) due to acute heart failure (AHF) result in hospital admission. These hospitalizations are expected to rise due to the aging population and increased survival of AHF and acute coronary syndrome (ACS).
Researchers from Vanderbilt University in Nashville, Tennessee conducted the Improving Heart Failure Risk Stratification in the ED (STRATIFY) study to develop a decision making tool that would identify AHF patients who can be safely discharged from the hospital to reduce the financial burden of AHF-related hospital admissions.
“STRATIFY is the first prospectively derived ED-based decision tool for identifying ED patients with AHF who are at low risk for 30-day adverse events using readily available variables,” the authors wrote. “We found an elevated troponin and abnormal renal function to be significantly associated with adverse events. Our tool was highly sensitive and able to identify patients at low risk for 30-day adverse events.”
The study included 1033 patients with diagnosed AHF in the ED from 4 hospitals between July 2007 and February 2011. Researchers reviewed the participants’ charts and conducted phone follow up interviews for 30 days to measure rates of adverse effects.
The adverse effects were then arranged on an ordinal scale, based on factors that could qualify patients for discharge, such as risk of death, ACS, cardiopulmonary resuscitation, mechanical cardiac support, and emergency revascularization. The researchers noted that safe discharge relies on patients’ hemodynamic status, impact of associated conditions, comorbidities, and the ability to provide self care.
The STRATIFY decision tool evaluated the statistics of discharge predictors by “degree of missingness and level of information provided.” STRATIFY analyzed 13 candidate predictor variables across a 6-level ordinal scale using a proportional odds model.
The data showed that 12% of patients experienced at least 1 adverse event in 30 days and 7% in 5 days. The STRATIFY tool had a C statistic of 0.68 (95% confidence interval [CI]: 0.63-0.74) and determined that 13% of patients had a <5% risk of 30-day adverse events and that 1.4% had a <3% risk.
The STRATIFY results also suggested that variables observed in an ED workup (eg, renal function, B-type natriuretic peptide, respiratory rate, and a history of dialysis) could help identify the low risk patients.
“If our decision tool shows similar test characteristics in a separate population, it may be incorporated into clinical practice and could have a significant impact on ED disposition decisions,” the authors concluded.
Collins SP, Jenkins CA, Harrell FE et al. Patients with Acute Heart Failure at Low Risk for 30-Day Adverse Events: The STRATIFY Decision Tool. J Am Coll Cardiol. 2015; 3(10): 737-747. doi:10.1016/j.jchf.2015.05.007