A recently validated, easy-to-use calculator of predicted 7-day mortality risk in patients presenting with acute decompensated heart failure is well worth incorporating into hospitalist clinical practice, Dustin T. Smith, MD, said at HM20 Virtual, hosted by the Society of Hospital Medicine.
The risk prediction tool, called the Emergency Heart Failure Mortality Risk Grade (EHMRG), can help guide clinical decision making as to whether a patient presenting with acute heart failure is appropriate for early discharge or should instead be admitted for inpatient monitoring and more aggressive therapy, explained Dr. Smith, a hospitalist at Emory University in Atlanta.
In addition to the EHMRG, other highlights of his wide-ranging update on recent practice-changing developments in heart failure directly relevant to hospitalists included the introduction of a simple, evidence-based tool for differentiating heart failure with preserved ejection fraction from other potential causes of unexplained dyspnea on exertion in euvolemic patients, and a study debunking what has been called the potassium repletion reflex in patients with acute heart failure undergoing diuresis.
The ACUTE study
Heart failure is an area of special interest for Dr. Smith. He has been surprised to find that virtually no hospitalists, emergency medicine physicians, or cardiologists he has spoken with have heard of the EHMRG or its validation in the ACUTE (Acute Congestive Heart Failure Urgent Care Evaluation) study. Yet this is a very handy tool for hospitalists, he observed.
The EHMRG algorithm utilizes nine variables for which data is readily available for every patient who arrives at the emergency department with acute heart failure. The variables are age, arrival by ambulance, heart rate, systolic blood pressure, potassium level, oxygen saturation, troponin, serum creatine, and presence or absence of active cancer. The information is entered into a cell phone app, which spits out the patient’s estimated 7-day mortality risk. The algorithm divides patients into one of five risk groups ranging from very low to very high. With the addition of data input as to the presence or absence of ST-segment depression on the 12-lead ECG, the weighted algorithm will simultaneously generate an estimated 30-day mortality risk.
ACUTE was a prospective, observational, real-world validation study of EHMRG involving 1,983 patients seeking emergency department care for acute heart failure at nine Canadian hospitals. The actual 7-day mortality rate was 0% in the very-low-risk group, 0% in the low-risk group, 0.6% with an intermediate-risk EHMRG, 1.9% with high risk, and 3.9% in the very-high-risk group. The corresponding 30-day mortality rates were 0%, 1.9%, 3.9%, 5.9%, and 14.3%.
The University of Toronto investigators also asked participating physicians for their clinical estimates of 7-day mortality risk while blinded to the EHMRG predictions. The algorithm proved more accurate than physician predictions across the board. Indeed, physicians consistently overestimated the mortality risk for all categories except the very-high-risk one, where they underestimated the true risk (Circulation. 2019 Feb 26;139:1146-56).
Given that heart failure remains year after year at the top of the list of most frequent causes for hospital admission, and that there is compelling evidence that many low-risk patients get hospitalized while potentially unsafe early discharges also occur, the EHMRG score fills an important unmet need.
“I think this can help inform us as to who with acute heart failure potentially needs to come into the hospital and who doesn’t,” Dr. Smith said. “I think the sweet spot here is that if you’re in the low- or very-low-risk category, your 7-day mortality is less than 1%; in fact, in this study it’s zero. But once you get to category 3 – the intermediate category – you’re talking about a 7-day mortality of 1%-2%, which I think is high enough to warrant hospital admission for treatment and to watch them, not just send them home.”