Diagnosis: Cardiac Asthma, Decompensated Systolic Heart Failure

This bedside echocardiogram demonstrates a severely depressed left ventricular ejection fraction. The IVC is 2-2.5 cm with < 50% collapse suggesting a high CVP. Further, the lung scan demonstrates bilateral diffuse B-Lines consistent with pulmonary edema. Putting this picture together, this patient has flash pulmonary edema from decompensated heart failure (CHF).

In the patient with severe respiratory distress and impending respiratory failure, it is imperative to institute the correct treatment plan immediately.

Wheezing is a physical exam finding classically associated with bronchospasm and obstructive lung disease. However, several studies of dyspneic patients have shown that the positive predictive value of this finding for COPD in emergency department patients is marginal, with a +LR of only 2-3.1-4

Bilateral crackles/rales are a physical exam sign classically associated with interstitial fluid from either CHF or ARDS. However, this finding has been found to be nonspecific as well. One study looked at asymptomatic elderly patients found that 1/3 of those age >75 had bilateral crackles at baseline.5

The term “cardiac asthma” describes patients who have decompensated heart failure, but present with primarily wheezing instead of crackles. It has been found to be present in up to 1/3 of CHF exacerbations in patients age > 65.6

B-Lines, when present on ultrasound in 3 or more lung fields bilaterally, have a positive likelihood ratio of > 20 for decompensated heart failure according to several studies.7,8 It has been found to be much more accurate than either chest X-ray or physical exam.9 However, one recent study demonstrated a mediocre +LR of 5.8 when B-Lines were present in 8 or more lung fields.10