Epidemiologic and clinical characteristics and course of acute heart failure and cardiogenic shock diagnosed in emergency departments

Objectives.

To describe the characteristics of patients diagnosed with acute heart failure (AHF) in emergency departments (EDs) who develop cardiogenic shock (CS) not associated with ST-segment elevation acute coronary syndrome (STACS).

Methods.

Information for patients diagnosed with AHF in 23 Spanish EDs and registered between 2009 and 2019 were included for analysis if the patients developed symptoms consistent with CS. We described baseline clinical characteristics related to cardiac decompensation and CS, as well as 30-day mortality.

Results.

A total of 15 920 cases of AHF were diagnosed; 179 of the patients developed CS (prevalence, 1.1%; 95% CI,
0.2%-3.2%). The median age was 82 years, and 53% were women. The most common causes of SC were valve disease and coronary disease. Prior episodes of AHF had occurred in 76%. More than 40% presented with severely deteriorated baseline functional and respiratory status. Treatment for CS was started in the ED in 75%, CS was refractory in 22%, and palliative measures were taken in 13%. Patients who developed CS had lower mean arterial pressure and worse New York Heart Association classifications at baseline, valve disease, and non-STACS. They had been transferred in an advanced life support ambulance, had severe hyponatremia, and less often had lower extremity edema than patients who did not develop CS. Thirty-day mortality was 38.5% (95% CI, 31.3%-45.7%); 21 of these patients died in the ED (12% of those with CS). Mortality was related to age 80 years or older (adjusted [aHR], 1.977; 95% CI, 1.169-3.343), hypertension (aHR, 2.123; 95% CI, 1.035-4.352), anemia (aHR, 2.262; 95% CI, 1.029-4.970), signs of low cardiac output (aHR, 1.877; 95% CI, 1.150-3.062), and a glomerularfiltration rate less than 30 mL/min/1.73 m2 (aHR, 1.758; 95% CI, 1.051-2.939).

Conclusions.

CS occurring outside a context of STACS is uncommon in ED patients with AHF and is related to poorer functional class. More of these patients have valve disease, hyponatremia, and non-STACS as a precipitant. Nearly 40% die in hospital. Almost a third die in the ED.