Acute heart failure is one of the main causes of acute respiratory distres in prehospital emergency setting. The early and correct diagnosis is important because the misdiagnosis can result in deleterious consequeance to patients. Rapid bedside tests (like NT-proBNP) and point-of-care lung ultrasound could be useful methods in field. This study confirmed that the combination of ultrasound sign in combination with rapid NT-proBNP test has a hibh diagnostic accuracy in differentiating between cardiac and pulmonray causes of acute dyspnea in the field and the tretament possibilities in clinical obscure cases are mainly improved.

Inclusion Criteria:

• Inclusion criterion for the study was shortness of breath as the primary complaint (defined as either the sudden onset of dyspnea without history of chronic dyspnea or an increase in the severity of chronic dyspnea).

Exclusion Criteria:

• Exclusion criteria were age <18 years, history of renal insufficiency, trauma, severe coronary ischemia (unless patient's predominant presentation was dyspnea), and other causes of dyspnea: pneumonia, pulmonary embolism, carcinoma, pneumothorax, pleural effusion, intoxications (drugs), anaphylactic reactions, upper airway obstruction, bronchial stenosis, and gastroesophageal reflux disorder

All patients with acute dyspnea in the time o the investigation in the field-prehospital settingInclusion criterion for the study was shortness of breath as the primary complaint (defined as either the sudden onset of dyspnea without history of chronic dyspnea or an increase in the severity of chronic dyspnea). Exclusion criteria were age <18 years, history of renal insufficiency, trauma, severe coronary ischemia (unless patient's predominant presentation was dyspnea), and other causes of dyspnea: pneumonia, pulmonary embolism, carcinoma, pneumothorax, pleural effusion, intoxications (drugs), anaphylactic reactions, upper airway obstruction, bronchial stenosis, and gastroesophageal reflux disorder, according to the history, clinical status, and additional laboratory tests available in prehospital setting (D-dimer, troponin, C-reactive protein)