Lung ultrasound versus lung auscultation to detect pulmonary congestion in patients with advanced heart failure before discharge.

BACKGROUND

Residual lung congestion is common in patients discharged after an acute heart failure (HF) hospitalization and represents a risk for HF rehospitalization. The aim of this study was to compare the diagnostic accuracy of B-lines on lung ultrasound and lung auscultation to detect residual congestion. We hypothesized that lung ultrasound would be more sensitive than physical examination.

METHODS

In this observational study of consecutive chronic HF patients discharged after an acute HF exacerbation, auscultation performed by two cardiologists and ultrasound examination performed by one experienced sonographer were compared at discharge. Residual congestion was defined by the presence of B-lines in all four zones and/or pleural effusion.

RESULTS

The study compared one hundred patients with severe heart failure (mean left ventricular (LV) ejection fraction 26%), mean age 70 years. Among the patients with signs of pulmonary congestion by lung auscultation, 31 zones were positive on lung ultrasound. Using positive ultrasound as reference, the accuracy of lung auscultation was 89.5%, with 52.5% sensitivity and 95.9% specificity. The positive and negative predictive values of lung auscultation were 68.9% and 92.1%, respectively.

CONCLUSION

Lung auscultation has a moderate sensitivity and high specificity for detecting residual lung congestion in patients with chronic HF before discharge compared to lung ultrasound. These findings suggest, that lung ultrasound should be implemented as part of the discharge exam for the detection of residual congestion.