With variable and nonspecific clinical manifestations [1], pulmonary embolism (PE) is associated with a mortality of approximately 30% and may cause sudden death within a few hours [2]. Therefore, diagnosis is challenging for clinicians as only 10–15% of patients underwent computer tomography pulmonary angiography (CTPA) were actually diagnosed as having the condition, which unavoidably leads to unnecessary and expensive investigations and adds their associated risks. Contrarily, in many rural hospitals of China, the CTPA cannot be performed for patients with suspected PE because of the lack of devices.