Ultrasound pleural effusion sign as a useful marker for identifying heart failure worsening in established heart failure patients during follow-up.

Clinical significance of UltraSound Pleural Effusion (US-PLE) and test characteristics of this sign for identifying worsening heart failure (HF) during follow-up of HF patients are unclear. Clinical records of 83 established HF patients were examined. The diagnosis of worsening HF was classified as "highly certain,""probable,""uncertain," or "no" based on the combination of the changes in symptoms/signs and B-type natriuretic peptide (BNP). Routine test included searching for the US-PLE sign. During a follow-up of 652±456 days, 1826 visits were evaluated. Among the 83 study patients, 78 had at least one of the following: worsening symptom(s), HF-related sign(s), and/or elevated BNP levels (≥3-fold increase) at one or more clinic visits. The US-PLE sign was present at 83 visits of 49 study patients. Its appearance was associated with the presence of HF-related symptom(s)/sign(s) and BNP elevation (odds ratio, 53-177, P<.0001 each). The test characteristics of the US-PLE sign for diagnosis of high possibility of worsening HF status fulfilling the "highly certain" or "probable" criteria were: sensitivity (76.6%), specificity (98.6%), positive predictive value (71.1%), and negative predictive value (99.0%). The US-PLE sign has high diagnostic accuracy for identifying worsening HF, including asymptomatic events, in HF patients during follow-up.