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What is 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 ? and explain in detail?
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.