An 85-year-old male with slurred speech and paralysis on the right side of the body is seen in the emergency department. A stat D-dimer is ordered and is very high. The physician suspects a thromboembolic event based on the D-dimer and needs to institute clot-dissolving therapy immediately. The most likely diagnosis and appropriate therapy for the patient is

• A. Myocardial infarction; treat with aspirin
• B. Pulmonary embolism; treat with warfarin
• C. Deep vein thrombosis; treat with heparin
• D. Stroke; treat with tissue plasminogen activator

Answer: (D)

In acute ischemic stroke, the priority is to restore blood flow to the affected brain tissue as quickly as possible. Slurred speech and right-sided weakness point to a focal neurologic deficit caused by a clot obstructing a cerebral artery, most likely on the left side. A very high D-dimer supports a thrombotic process but does not by itself diagnose stroke or determine therapy; the crucial step is confirming that there is no intracranial hemorrhage and initiating reperfusion.

The best treatment in this scenario is intravenous tissue plasminogen activator, which converts plasminogen to plasmin and dissolves the clot to reestablish cerebral perfusion. This thrombolytic therapy is time-sensitive and is most effective when given within the established window after symptom onset and when imaging rules out hemorrhage and there are no contraindications.

Aspirin may be used later for secondary prevention but is not the initial thrombolytic therapy in an acute ischemic stroke. Warfarin is a long-term anticoagulant and not the immediate treatment for stroke. The presentation here is neurologic rather than cardiopulmonary, so thrombolysis with tPA is the appropriate choice.