Elderly people constitute the largest proportion of emergency department (ED) patients, representing 12% of all ED admissions. The need for diagnostic tests or therapeutic interventions is much greater in this patient population. Cardiovascular diseases and symptoms represent 12% of the causes for ED admission, and patients suffering from cardiovascular disease are those whose ED visit lasts longest.

The diagnostic approach in the ED in elderly patients admitted for acute dypsnoea is complex, and early identification of acute left-sided heart failure (ALSHF) is vital as it has an impact on prognosis. The clinical signs are difficult to interpret, and are non-specific, particularly at the acute phase and in elderly or obese patients. Indeed, some authors have reported up to 50% of diagnostic errors in elderly patients.

Measure of the blood concentration of a natriuretic peptide allows a quick diagnosis. However, peptides alone suffer from several limitations, particularly in situations that are often encountered in elderly patients, such as sepsis, renal failure, acute coronary syndrome, pulmonary embolism, chronic respiratory failure, atrial fibrillation and high body mass index. Diagnostic performance deteriorates with increasing age, and there is a significant increase in this grey-zone in patients aged ≥75 years. In critical situations in elderly patients, assessment of natriuretic peptides serve mainly to rule out a diagnosis of left heart failure.

Some authors have studied other biomarkers showing their performance in the diagnosis of ALSHF. These are biomarkers involved in remodeling and myocardial fibrosis (ST2, Galectin-3) or involved in myocardial injury (High-sensitivity Troponin-I).

Therefore, a combined "multimarker" approach could improve the diagnostic performance of ALSHF.

READ (NCT02531542) is a diagnostic study including patients over the age of 75 admitted to acute dyspnea in the ED, to demonstrate the superiority of an ultrasound protocol (the READ protocol) on NT-proBNP in the ALSHF diagnosis.

The hypothesis is that the diagnostic accuracy of a multimarker diagnostic approach, namely the READ-MA method, combining NT-proBNP, High-sensitivity Troponin-I, ST2 and Galectin-3 would be superior to that of NT-proBNP assessment for the diagnosis of ALSHF in elderly patients (≥75 years) admitted to the ED.

Inclusion Criteria :

• Admission to the Emergency Department with age ≥ 75 years
• AND criteria of acute dyspnea :

Breathe rate ≥ 25 cycles/minute or PaO2 ≤ 70 mmHg or SpO2 ≤ 92% in room air or PacO2 ≥ 45 mmHg and pH ≤ 7.35

- AND Electrocardiogram in sinus rhythm or in atrial fibrillation at admission

Exclusion Criteria:

• none

All patients aged ≥75 years admitted to the ED for acute dyspnea