What is an indication for pulmonary angiography?

An indication for pulmonary angiography is the suspicion of a pulmonary embolus. This imaging procedure is specifically utilized to visualize the blood vessels in the lungs to detect blockages caused by emboli, which are typically blood clots that have traveled from other parts of the body, such as the legs. The prompt diagnosis of a pulmonary embolism is critical, as it can be a life-threatening condition. By performing a pulmonary angiography, healthcare providers can assess the extent of any blockage and decide on the appropriate treatment options.

The other options listed are factors that may complicate the procedure or influence the decision to conduct angiography, but they do not serve as direct indications for the procedure itself. Compromised renal function poses a risk during contrast administration, coagulopathy presents a bleeding risk during the procedure, and a previous history of contrast reaction suggests a need for caution or alternative imaging techniques, but none of these are direct indications for performing a pulmonary angiography.