ABSTRACT
Electrocardiography (ECG) in acute PE usually shows sinus tachycardia. The presence of classic S1Q3T3 pattern may help in making diagnosis; however, this is not commonly seen. Other findings may include incomplete or complete right bundle branch block and right axis deviation. The presence of Qr pattern in lead V1 and inverted T waves in anterior precordial leads indicates increased risk of poor clinical outcomes (5). A negative D-dimer has high negative predictive value (>90%) and low specificity (45%) for PE (6-8). Therefore, the test is useful only as a “rule-out” modality in the office setting or emergency room. Arterial blood gas analysis should not be used for screening purposes because of it’s low specificity in PE, but may help direct therapy. The presence of hypoxemia, hypocapnia, respiratory alkalosis, and increased alveolar-arterial gradient is usually seen (9).
