12CC - Case of the Month

Clinical Case: Mature Female, Hemiparesis

History of Present Illness:

A 79-year-old female presented to the emergency department withaltered mental status and left-side hemiparesis 30 minutes prior toarrival. She had no history of hypertension.

Examination: Vital signs were pulse 55beats/min, blood pressure 155/87 mm Hg (left arm) and 100/77(rightarm), respirations 19 breaths/min, oxygen saturation 98% (ambientair), and temperature 36.4°C (97.5°F). Grade III diastolic murmurover right sternal border was heard by auscultation. Right radialpulse was weaker as compared with contralateral side. LeftBabinski's sign was present. D-dimer was 5791 ng/ml. A computertomography(CT) of brain revealed gyrus effacement in right middlecerebral artery territory (Figure1). A magnetic resonanceimage(MRI) of brain revealed multiple cerebral infarction(figure2).A transthoracic echocardiography showed massive pericardialeffusion. A contrast CT of chest (figure3) was arranged

Questions:

1)     What is the pretest probability foran abnormal Chest CTA finding.

2)     If you were managing this patient,which study would you have ordered first.