Background: Thoracic sonography searching for pleural effusion is helpful in diagnosing heart failure (HF) in emergency situations, but utility of this test for follow-up examination of chronic HF patient is unknown.
Hypothesis: Thoracic sonography searching for pleural effusion may be suitable for monitoring deterioration in chronic HF outpatients during long-term follow-up.
Methods: Patients with stable HF at the time of study entry, but with previous deterioration (n = 46) were recruited and followed between June 2003 and September 2005. Evaluated HF-related variables included symptoms and signs of HF, pleural effusion on an ultrasonogram, and B-type natriuretic peptide (BNP) levels.
Results: During the study period, 26 patients developed deterioration in chronic HF and 20 maintained a stable clinical course. Of the 26 patients with deteriorating HF, 25 (96%) demonstrated objective HF-related sign(s) under examination. Among the signs tested in the present study, pleural effusion on a sonogram was the leading HF-related sign (77%), followed by rales (46%) and edema (46%). Eleven patients (42%) presented with only one feature, in which pleural effusion on a sonogram was the most frequent (7 of 11 patients). Using plasma BNP levels as a reference for HF deterioration, sonographic detection of pleural effusion exhibited the highest sensitivity (74%), best negative predictive value (73%), and highest predictive accuracy (78%) for identifying patients with higher BNP levels at deterioration compared to stable periods.
Conclusions: Thoracic sonography allows sensitive detection of HF deterioration and improves clinical decision making in outpatient clinic during follow-up examination of HF patient with previous decompensation.