Pulmonary embolism is a potentially life-threatening condition. Despite advances in diagnostics, lack of consensus and delays in determining the diagnosis of pulmonary embolism are still important problems. We report the diagnosis and management of a 37-year-old man suffering from massive pulmonary embolism, a large protruding thrombus, and dilated cardiomyopathy. Echocardiography showed dilatation of all cardiac chambers, a large protruding thrombus in the right atrium to the inferior vena cava, impaired left and right ventricular systolic function, and global hypokinetic of the left ventricle with eccentric left ventricular hypertrophy. A thoracic computerized tomography scan showed pulmonary embolism with infarction. The patient's blood pressure was 60/40 mmHg and heart rate was 110 bpm. The patient was diagnosed with high-risk acute pulmonary embolism. We gave him hemodynamic support and reperfusion therapy with a loading dose of 250,000 units of Streptokinase followed by 100,000 units/hour for 24 hours. After revascularization, the patient's hemodynamic condition improved. The diagnosis of acute pulmonary embolism is based on clinical symptoms, hemodynamic changes, or radiological examination. Unstable hemodynamic underlies high-risk stratification. Hypotension or shock results from obstruction of the pulmonary artery which causes increased right ventricular afterload and acute right ventricular dysfunction. Reperfusion with thrombolysis therapy could provide good outcomes in this patient. Prolonged anticoagulation should be given to prevent the recurrence of venous thromboembolism.