In suspected pulmonary embolism, which initial finding would be the strongest indication for thrombolytic therapy?

In suspected pulmonary embolism, which initial finding would be the strongest indication for thrombolytic therapy?

• A. Tachycardia
• B. Hypoxemia
• C. Hypotension
• D. Elevated D-dimer

Answer: (C)

In massive pulmonary embolism, the key factor guiding urgent thrombolysis is hemodynamic instability, specifically hypotension. When the embolus severely obstructs the pulmonary vasculature, the right ventricle acutely strains and systemic blood pressure falls, signaling that rapid reperfusion of the lung is critical to restore perfusion and prevent multi-organ failure. Thrombolytic therapy can quickly dissolve the clot and improve survival in this scenario. Tachycardia is common in PE but nonspecific and does not alone indicate the need for thrombolysis. Hypoxemia shows impaired gas exchange but can occur from many causes and does not inherently reflect the hemodynamic status driving the decision. An elevated D-dimer helps with diagnosis but is not a trigger for thrombolytic therapy in the acute setting.

In massive pulmonary embolism, the key factor guiding urgent thrombolysis is hemodynamic instability, specifically hypotension. When the embolus severely obstructs the pulmonary vasculature, the right ventricle acutely strains and systemic blood pressure falls, signaling that rapid reperfusion of the lung is critical to restore perfusion and prevent multi-organ failure. Thrombolytic therapy can quickly dissolve the clot and improve survival in this scenario.

Tachycardia is common in PE but nonspecific and does not alone indicate the need for thrombolysis. Hypoxemia shows impaired gas exchange but can occur from many causes and does not inherently reflect the hemodynamic status driving the decision. An elevated D-dimer helps with diagnosis but is not a trigger for thrombolytic therapy in the acute setting.