This study focuses on two serious and common medical conditions: heart failure and pulmonary embolism (a blood clot in the lungs). Heart failure happens when the heart cannot pump blood effectively, and it is one of the main reasons older adults are admitted to the hospital. Pulmonary embolism can be life-threatening and may worsen heart failure or even trigger it.

Doctors believe that pulmonary embolism may often go undetected in patients who come to the hospital with symptoms of acute heart failure, such as sudden shortness of breath. This is because both conditions can cause similar symptoms, making it difficult to tell them apart. As a result, doctors may sometimes assume the symptoms are only due to heart failure and not investigate further for a possible blood clot.

However, missing a pulmonary embolism can have serious consequences. Studies suggest that some patients with heart failure who die may actually have had an undiagnosed pulmonary embolism. Current medical guidelines recommend checking for pulmonary embolism when the cause of breathing problems is unclear, but in real-life practice, this is not always done.

The goal of this study is to find out whether pulmonary embolism is underdiagnosed in patients with suspected acute heart failure and whether systematically testing for it could improve patient outcomes.

To do this, the study will compare two approaches in several hospitals. In half of the hospitals, doctors will follow their usual practice and decide case by case whether to test for pulmonary embolism. In the other half, doctors will systematically test all eligible patients for pulmonary embolism using recommended diagnostic methods.

Adult patients admitted with recent or worsening breathing difficulties and signs of acute heart failure may be included in the study, provided they give their consent. Researchers will collect information about their symptoms, tests, diagnosis, and treatments.

Patients will be monitored during their hospital stay and for three months afterward. The study will track important outcomes such as survival, new blood clots, bleeding events, repeated hospital visits for breathing problems, and overall time spent in the hospital.

The researchers expect to include about 740 patients in total. They estimate that pulmonary embolism may be found in about 1% of patients with usual care, but up to 5% when doctors systematically look for it.

This study aims to better understand how often pulmonary embolism occurs in patients with acute heart failure and whether more systematic testing could lead to earlier diagnosis and better care. The results could help improve medical practice and reduce complications or deaths related to missed diagnoses.

Inclusion Criteria:

• Adult patient (≥18 years)

• Admission to the emergency department or cardiology unit of a participating center

• Recent onset or worsening dyspnea and/or orthopnea

• Diagnosis of acute heart failure defined by recent dyspnea associated with at least one of the following:

  • Bilateral pulmonary crackles on auscultation and/or peripheral edema
  • Signs of pulmonary congestion on chest X-ray or lung/cardiac ultrasound
  • Elevated natriuretic peptide levels (BNP or NT-proBNP)
  • Documented history of heart failure (known chronic heart failure or prior hospitalization for acute heart failure)

• Patient affiliated with or beneficiary of a social security system

• Patient able and willing to provide free, informed, and written consent

Exclusion Criteria:

• Shock state suggesting cardiogenic shock and/or severe pulmonary embolism
• Severe respiratory distress at inclusion preventing appropriate positioning or performance of imaging examinations
• Evidence of acute coronary syndrome on electrocardiogram at admission
• Severe renal impairment (creatinine clearance <30 mL/min)
• Known hypersensitivity or allergy to iodinated contrast agents
• Ongoing therapeutic anticoagulation for more than 48 hours prior to admission
• Hospitalization for more than 48 hours prior to inclusion
• Inability to ensure 90-day follow-up (e.g., end-of-life situation, no fixed address, patient not reachable)
• Inadequate understanding of the French language preventing proper study information and consent
• Pregnant, breastfeeding, or postpartum women
• Individuals under legal protection or other vulnerable populations, including minors and protected adults, in accordance with applicable public health regulations (Articles L.1121-5 to L.1121-8 and L.1122-1-2 of the French Public Health Code)