A 75 - year - old lady with severe chronic obstructive pulmonary disease (COPD) presents with acute breathlessness. The chest X - ray shows there is no focal consolidation. She is afebrile, but D - dimers are markedly elevated. Which of the following is best investigation to diagnose this condition ?: (A) MRI, (B) Ventilation - perfusion (V/Q) scan, (C) High resolution CT thorax, (D) CT pulmonary angiography
Answer is D. The patient has a possible Pulmonary embolus. Gold standard for diagnosis of PEa Pulmonary angiography V/Q is difficult to interpret in patients with cardiorespiratory disease. V/Q is IOC in iodine allergics and pregnancy.