Which classification of Pulmonary Embolism is characterized by a large blockage?

The classification of pulmonary embolism as "massive" pertains to a significant blockage that obstructs a major pulmonary artery or a large branch, severely impacting blood flow. This type of embolism typically is associated with a high degree of morbidity and mortality due to its capacity to compromise pulmonary circulation, leading to acute right heart strain, reduced cardiac output, and often causing cardiovascular collapse.

When clinicians refer to a "massive" pulmonary embolism, they are usually indicating that there are life-threatening consequences due to the extent of blockage, which may manifest as hypotension or cardiovascular instability upon presentation. The substantial size of the blockage necessitates immediate intervention to restore normal perfusion and stabilize the patient.

In contrast, the other classifications—such as submassive, minor, or severe—describe less extensive blockages or varying levels of impact on hemodynamics. For example, submassive may indicate a blockage that causes some degree of right heart strain but does not meet the criteria for massive embolism. Minor embolisms typically have a much lower significance, causing mild symptoms or none at all. Understanding these distinctions is crucial for emergency responders and healthcare providers in prioritizing treatment and predicting patient outcomes.