Rapid evaluation by lung-cardiac-inferior vena cava (LCI) integrated ultrasound for differentiating heart failure from pulmonary disease as the cause of acute dyspnea in the emergency setting

Abstract

Background: Rapid and accurate diagnosis and management can be lifesaving for patients with acute dyspnea. However, making a differential diagnosis and selecting early treatment for patients with acute dyspnea in the emergency setting is a clinical challenge that requires complex decision-making in order to achieve hemodynamic balance, improve functional capacity, and decrease mortality. In the present study, we examined the screening potential of rapid evaluation by lung-cardiac-inferior vena cava (LCI) integrated ultrasound for differentiating acute heart failure syndromes (AHFS) from primary pulmonary disease in patients with acute dyspnea in the emergency setting.

Methods: Between March 2011 and March 2012, 90 consecutive patients (45 women, 78.1 ± 9.9 years) admitted to the emergency room of our hospital for acute dyspnea were enrolled. Within 30 minutes of admission, all patients underwent conventional physical examination, rapid ultrasound (lung-cardiac-inferior vena cava [LCI] integrated ultrasound) examination with a hand-held device, routine laboratory tests, measurement of brain natriuretic peptide, and chest X-ray in the emergency room.

Results: The final diagnosis was acute dyspnea due to AHFS in 53 patients, acute dyspnea due to pulmonary disease despite a history of heart failure in 18 patients, and acute dyspnea due to pulmonary disease in 19 patients. Lung ultrasound alone showed a sensitivity, specificity, negative predictive value, and positive predictive value of 96.2, 54.0, 90.9, and 75.0%, respectively, for differentiating AHFS from pulmonary disease. On the other hand, LCI integrated ultrasound had a sensitivity, specificity, negative predictive value, and positive predictive value of 94.3, 91.9, 91.9, and 94.3%, respectively.

Conclusions: Our study demonstrated that rapid evaluation by LCI integrated ultrasound is extremely accurate for differentiating acute dyspnea due to AHFS from that caused by primary pulmonary disease in the emergency setting.

Figure 1

Algorithm for the diagnosis of acute dyspnea based on the lung-cardiac-inferior vena cava integrated ultrasound. LVEF = left ventricular ejection fraction; MR = mitral regurgitation; TR = tricuspid regurgitation; IVC = inferior vena cava.

Figure 2

Imaging of lung-cardiac-inferior vena cava(LCI)integrated ultrasound. (A) Imaging of the lung ultrasound: Alines (upper) and B-lines (lower). (B) Imaging of the cardiac ultrasound: Apical long-axis view (upper) and moderate mitral regurgitation (lower). (C) Imaging of the inferior vena cava ultrasound: Collapsibility ≥ 50% (upper) and < 50% (lower).