What is the Difference Between Massive and Submassive Pulmonary Embolism?

The main difference between massive and submassive pulmonary embolism lies in the presence of hypotension and the severity of the condition. Both massive and submassive pulmonary embolism occur due to a blockage of the pulmonary artery, causing life-threatening conditions and preventing blood flow to the lungs.

Massive Pulmonary Embolism:

• Characterized by systemic hypotension, defined as a systolic arterial pressure < 90 mmHg.
• Acute pulmonary embolism with obstructive shock or systolic blood pressure (SBP) < 90 mmHg.
• High mortality rate, despite advances in diagnosis and therapy.
• Can cause severe cardiopulmonary failure and ventricular dysfunction or myocardial necrosis.

Submassive Pulmonary Embolism:

• Acute pulmonary embolism without systemic hypotension (SBP ≥ 90 mmHg).
• Characterized by RV dysfunction or hypokinesis confirmed by echocardiography.
• A subgroup of patients with nonmassive pulmonary embolism who are hemodynamically stable.
• Prognosis is different from that of others with non-massive pulmonary embolism and normal RV function.

In summary, the key difference between massive and submassive pulmonary embolism is the presence of hypotension in massive cases, while submassive cases do not develop systemic hypotension. Massive pulmonary embolism is associated with a higher mortality rate and more severe cardiopulmonary complications.

Comparative Table: Massive vs Submassive Pulmonary Embolism

Here is a table comparing massive and submassive pulmonary embolism:

In summary, massive pulmonary embolism is characterized by systemic hypotension and has a high mortality rate, while submassive pulmonary embolism does not develop systemic hypotension and has a lower mortality rate. Both conditions require prompt diagnosis and treatment to reduce the risk of complications and death.