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Decompensated CHF is commonly precipitated by

acute coronary syndrome (ACS), rapid atrial fibrillation,

acute renal failure, or medication and dietary noncompliance. Other important precipitants to consider are pulmonary embolus, uncontrolled hypertension, profound

anemia, thyroid dysfunction, and states of increased meta ­

bolic demand such as infection. Cardiotoxic drugs including alcohol, cocaine, and some chemotherapeutic agents

should also be considered.

CLINICAL PRESENTATION

� History

Patients most commonly present with shortness of breath

with exertion or at rest with severe exacerbations.

CHAPTER 15

Orthopnea, or dyspnea while lying flat, is common as a

result of the redistribution of fluid from the lower

extremities to the central circulation when the legs are

elevated. The increase in central circulation produces a

higher pulmonary capillary wedge pressure and secondary

pulmonary edema. Attempt to quantify the severity of the

orthopnea by asking on how many pillows the patient

sleeps and note any changes from baseline. Paroxysmal

nocturnal dyspnea occurs when sleeping patients awake

suddenly with marked shortness of breath with the need to

sit up and hang the legs over the side of the bed o r g o to a

window for air. In certain patients, pulmonary congestion

presents rather occultly with a persistent mild nocturnal

cough as the only symptom.

Patients may complain of peripheral edema, but this is

neither sensitive nor specific for CHF and should prompt

an investigation for alternative etiologies. Right upper

quadrant pain may occur in patients with hepatic congestion and can be confused with biliary colic.

Always obtain a detailed review of systems to try to

identify any possible precipitants of CHF. Specifically, ask

patients about antecedent or ongoing chest pain, palpitations, recent illnesses or infections, and medication or

dietary changes or noncompliance.

� Physical Examination

Quickly evaluate patient stability with a careful assessment

of vital signs and a focused physical exam. Check the respiratory rate, obtain a pulse oximetry, look for accessory

muscle use, and determine whether the patient can speak

in complete sentences to assess the severity of respiratory

distress. Decreased stroke volume and impaired cardiac

output may manifest as tachycardia, a narrowed pulse

pressure, or marked peripheral vasoconstriction. Recognize

hypotension and/or signs of hypoperfusion immediately

and treat as cardiogenic shock.

After the initial assessment, focus on signs of total body

volume overload. Patients with left ventricular failure typically present with pulmonary signs, including inspiratory

crackles, a persistent cough, or a "cardiac wheeze." Patients

with right ventricular failure show signs of systemic congestion. Check for peripheral edema, j ugular venous distention, and hepatojugular reflux (an increase in jugular

venous pressure with deep palpation of the right upper

quadrant) (Figure 15-1). Auscultate the heart for murmurs

or gallops. Although often difficult to appreciate in the

emergency department (ED), an S3 gallop is highly specific

for decompensated heart failure.

DIAGNOSTIC STUDIES

� Laboratory