S.O.B With Chest Pressure in A 55-Year O
zkadhem - 06-17-09 17:00



A 55-year-old man presents to the emergency department (ED) with a 1-month history of worsening shortness of breath and chest pressure. He was discharged from the hospital 3 weeks ago after a negative cardiac work-up and a stress test for these symptoms. He was followed up by his primary care provider (PCP) for worsening symptoms and a productive cough. At that time, he was diagnosed with asthma after undergoing pulmonary function testing, and he was started on fluticasone/salmeterol, prednisone, and albuterol. He then returned to the ED with worsening symptoms, including exertional dyspnea, cough with trace hemoptysis, chest pressure and exertional fatigue. Repeat cardiac enzyme tests and chest radiographs were all negative. An electrocardiogram (ECG) was also normal. Noncontrast computed tomography (CT) scanning of the chest was read as negative, and a consult was ordered for pulmonary evaluation. He returned to the PCP 1 week later complaining of worsening symptoms over a 3-4 day period and was referred to the ED today. The symptoms did not resolve despite treatment with an albuterol nebulizer. The patient denies having any fever, chills, nausea, vomiting, swelling in the lower extremities, rapid breathing, chest pain, or pain radiating down his left arm. The patient's only travel history was over 2 months ago, when he drove 8 hours to New York and back. His past medical history includes hypertension, hypothyroidism, benign prostatic hyperplasia, obesity, sinusitis, obstructive sleep apnea, and gout. His past surgical history is significant for thyroidectomy, right ankle reconstruction, and a lumpectomy for removal of a benign right breast mass. The patient's current medications include cetirizine hydrochloride, fluticasone/salmeterol, celecoxib, metoprolol, doxazosin mesylate, allopurinol, benazepril, levothyroxine, and fluticasone propionate. He has no known drug allergies and does not use illicit drugs. He does occasionally drink alcohol and, although he quit 10 years ago, he has a past history of tobacco use (approximately 1-2 packs per day for 15 years).

On physical exam, the patient's oral temperature is 95.5°F (35.3°C), pulse is 78 bpm, blood pressure is 96/86 mm Hg, respiratory rate is 18 breaths/min, and oxygen saturation is 90% while breathing room air. The examination of his head and neck is normal. He has decreased breath sounds in the right anterior lower lung fields, with no rales, wheezing, rhonchi, or rubs. His heart has a regular rate and rhythm, with no gallops, rubs, or murmurs. His S1 and S2 heart sounds are normal. His abdomen is soft and nontender, with normal bowel sounds and no organomegaly. The peripheral arterial pulses in all extremities are equal and palpable bilaterally. He has no edema, tenderness, or erythema in his extremities.

The laboratory analysis, including a complete blood cell count (CBC), basic metabolic panel, cardiac enzymes, and coagulation studies are normal, with the only exception being his bicarbonate reading, which is 20 mEq/L (20 mmol/L; normal range, 21-30 mEq/L). An ECG is performed, which shows a normal sinus rhythm with an incomplete right bundle branch block and T-wave abnormalities consistent with anterolateral ischemia. An echocardiogram is obtained that reveals pulmonary hypertension, tricuspid regurgitation, right atrial and ventricular enlargement, and a pulmonary artery pressure of 80 mm Hg (his previous echocardiogram, which was obtained a month earlier, was read as normal). A high-resolution, contrast-enhanced CT angiogram of the chest is ordered (see Figure 1).
Based on the presentation and the high-resolution CT angiography of the chest, what is the diagnosis?