Does this dyspneic patient in the emergency department have congestive heart failure?

CONTEXT: Dyspnea is a common complaint in the emergency department where physicians must accurately make a rapid diagnosis.

OBJECTIVE: To assess the usefulness of history, symptoms, and signs along with routine diagnostic studies (chest radiograph, electrocardiogram, and serum B-type natriuretic peptide [BNP]) that differentiate heart failure from other causes of dyspnea in the emergency department.

DATA SOURCES: We searched MEDLINE (1966-July 2005) and the reference lists from retrieved articles, previous reviews, and physical examination textbooks.

STUDY SELECTION: We retained 22 studies of various findings for diagnosing heart failure in adult patients presenting with dyspnea to the emergency department.

DATA EXTRACTION: Two authors independently abstracted data (sensitivity, specificity, and likelihood ratios [LRs]) and assessed methodological quality.

DATA SYNTHESIS: Many features increased the probability of heart failure, with the best feature for each category being the presence of (1) past history of heart failure (positive LR = 5.8; 95% confidence interval [CI], 4.1-8.0); (2) the symptom of paroxysmal nocturnal dyspnea (positive LR = 2.6; 95% CI, 1.5-4.5); (3) the sign of the third heart sound (S(3)) gallop (positive LR = 11; 95% CI, 4.9-25.0); (4) the chest radiograph showing pulmonary venous congestion (positive LR = 12.0; 95% CI, 6.8-21.0); and (5) electrocardiogram showing atrial fibrillation (positive LR = 3.8; 95% CI, 1.7-8.8). The features that best decreased the probability of heart failure were the absence of (1) past history of heart failure (negative LR = 0.45; 95% CI, 0.38-0.53); (2) the symptom of dyspnea on exertion (negative LR = 0.48; 95% CI, 0.35-0.67); (3) rales (negative LR = 0.51; 95% CI, 0.37-0.70); (4) the chest radiograph showing cardiomegaly (negative LR = 0.33; 95% CI, 0.23-0.48); and (5) any electrocardiogram abnormality (negative LR = 0.64; 95% CI, 0.47-0.88). A low serum BNP proved to be the most useful test (serum B-type natriuretic peptide <100 pg/mL; negative LR = 0.11; 95% CI, 0.07-0.16).

CONCLUSIONS: For dyspneic adult emergency department patients, a directed history, physical examination, chest radiograph, and electrocardiography should be performed. If the suspicion of heart failure remains, obtaining a serum BNP level may be helpful, especially for excluding heart failure.