Low Dose Prolonged Infusion of Tissue Type Plasminogen Activator Therapy in Massive Pulmonary Embolism
Low Dose Prolonged Infusion of Tissue Type Plasminogen Activator Therapy in Massive Pulmonary Embolism
The aim of the present study was to assess the effects of low-dose (25mg) prolonged
 administration (in 6 hours) of tissue type plasminogen activator (tPA) on in-hospital
 mortality and outcomes in patients with massive PE.
Pulmonary embolism (PE) is life threatening disease requiring early diagnosis and treatment.
 Thrombolytic therapy (TT) is required in patients with massive PE. PE has a high mortality
 but the in-hospital all-cause case mortality rates were lower in unstable patients who
 received TT than those who did not. However, it was reported that minority (nearly 30%) of
 unstable patients received thrombolytic therapy. The reason that majority of unstable
 patients failed to receive thrombolytic therapy is unclear. The higher rates of complications
 including the life threatening bleeding may be a reason of reluctance in the use of TT.

 The lungs are the only organ receiving the entire cardiac output. Therefore, they are the
 point of convergence for the entire molecules of the thrombolytic agent, independent from the
 route of administration. So that lower doses of the TT might be effective in PE, with the
 additional benefits of enhancing its safety profile. The percutaneous endovenous intervention
 for deep venous thrombosis has suggested an exquisitely favorable pulmonary response to
 low-dose thrombolysis. The aim of the present study was to assess the effects of low-dose
 (25mg) prolonged administration (in 6 hours) of tissue type plasminogen activator (tPA) on
 in-hospital mortality and outcomes in patients with massive PE.

 The primary end points consisted of in hospital all cause mortality, major complications,
 pulmonary hypertension and right ventricular dysfunction. Secondary points are all cause
 mortality, pulmonary hypertension and right ventricular dysfunction at 6 month.
Inclusion Criteria:

 Patients with massive PE aged 18 years or older with confirmed PE and able to give informed
 consent will be included in the study. PE is defined according to current guidelines as
 adult patients presenting with signs and symptoms suggestive of PE plus imaging
 documentation on computed tomography angiography. Massive PE was defined as acute PE with
 sustained hypotension (systolic blood pressure<90 mm Hg for at least 15 minutes or
 requiring inotropic support, not due to a cause other than PE, such as arrhythmia,
 hypovolemia, sepsis, or left ventricular [LV] dysfunction), pulselessness, or persistent
 profound bradycardia (heart rate<40 bpm with signs or symptoms of shock).

 Exclusion Criteria:

 Patients with prior intracranial hemorrhage, known structural intracranial cerebrovascular
 disease (eg, arteriovenous malformation), known malignant intracranial neoplasm, ischemic
 stroke within 3 months, suspected aortic dissection, active bleeding or bleeding diathesis,
 recent surgery encroaching on the spinal canal or brain, and recent significant closed-head
 or facial trauma with radiographic evidence of bony fracture or brain injury were excluded
 from the study.