The role of thoracic ultrasonography for evaluation of patients with decompensated chronic heart failure

Abstract

Objectives: This study examined the usefulness of thoracic ultrasonography for evaluation of fluid accumulation in patients with decompensated chronic heart failure (CHF) in comparison with physical signs, upright posteroanterior chest X-ray and echocardiography.

Background: Decompensated CHF is frequently accompanied by pleural effusion, suggesting that pleural effusion is a useful marker for confirming the diagnosis of the uncontrolled stage of CHF. Thoracic ultrasonography seems to be adequate for this purpose.

Methods: Patients with uncontrolled CHF and an interpretable physical examination, chest X-ray, ultrasonogram for the heart and thorax and thoracic X-ray computed tomographic (CT) scan were enrolled in the study (n = 60). Patients free from thoracic and cardiovascular diseases served as a control (n = 22). Thoracic CT scan was used as the gold standard for the presence or absence of pleural effusion. Variables used to predict body fluid accumulation included the following: pulmonary rales, jugular venous distension or peripheral edema, roentgenographic evidence of pulmonary edema or pleural fluid, pericardial or pleural effusion on ultrasonographic study.

Results: The reported incidence of pleural effusion detected by thoracic ultrasonography was high (91%). The incidence of physical signs and roentgenographic signs of body fluid accumulation, however, was modest (56%) to low (33%). The best clinical variable for identifying patients with decompensated CHF was the detection of pleural fluid by thoracic ultrasonography (91% predictive accuracy). This variable also had high interobserver agreement (95% overall agreement, kappa = 0.70). There was only 41% to 65% predictive accuracy of other clinical variables, with 72% to 95% agreement (kappa = 0.400-0.848).

Conclusions: Thoracic ultrasonography is a simple, sensitive and accurate method for the evaluation of body fluid accumulation in patients with decompensated CHF. This technique can be used to assist in making the diagnosis of decompensated CHF if other causes of pleural effusion have been clinically ruled out.