35 year old male with history of 4 weeks of immobilization for fracture femur developed sudden onset of chest pain and hemoptysis.  ECG shows s1 Q3 T3 pattern. Diagnosis?: (A) Acute myocardial infarct, (B) COPD, (C) Pulmonary embolism, (D) Cor pulmonale
Answer is C. Ref. Grainger and Allison's Diagnostic Radiology. Page. 50
 
Pulmonary embolism (PE) usually arises from a venous thrombosis in the pelvis or legs

Risk factors include any cause of immobility or hyper coagulability .
Clinical features include :pleuritic chest pain ,sudden onset of breathlessness (most common),hemoptysis ,dizziness ,syncope .
ECG findings include sinus tachycardia (most common ) , S1Q3T3 (Most characteristic)