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).