A patient (man, 87 years old) visited our hospital with suffocation for 3 days on August 31, 2019. This patient had a history of hypertension treated with valsartan amlodipine compound, with blood pressure 150/70 mmHg and 60 heartbeats per minute in peacetime. In addition, this patient had a history of lower extremity varicose veins without any therapy. We did some laboratory tests and examinations for this patient immediately after admission to the hospital. Whole blood count analysis revealed a white blood cell count of 9.1 x 109/l (reference range 3.5-9.5 x 109/l), haemoglobin level of 134 g/l (reference range 115-150 g/l), hematocrit level of 37.3% (reference range 40-50%), and a platelet count of 154 x 109/l (reference range 125-350 x 109/l). The results of NT-proBNP and creatine were 10671 pg/ml (reference range 0-1800 pg/ml) and 125.7 mumol/l (reference range 20-98 mumol/l), respectively. The level of troponin was normal. Further examination showed that autoantibodies were normal. The blood pressure was 120/80 mmHg, with 80 heartbeats per minute when admitted to the hospital. No thrombus was found in the lower extremity venous ultrasound examination. And pulmonary artery computed tomography angiography (CTA) showed bilateral pulmonary embolism (Figures 1(a) and 1(b)). Electrocardiogram showed right bundle branch block, and echocardiogram showed larger right ventricular transverse diameter (43 mm), decreased left ventricular end diastolic anteroposterior diameter (43 mm), and higher pulmonary artery pressure (89 mmHg). According to the clinical manifestations, blood pressure (20% lower than basal blood pressure), CTA, NT-proBNP, and echocardiogram, this patient was diagnosed with submassive pulmonary embolism. Pulmonary angiography was done on August 31, 2019, and the result confirmed pulmonary embolism. In addition, percutaneous mechanical pulmonary thrombectomy was done using the Angiojet system. The injection pattern by urokinase (urokinase 25 wiu + sodium chloride injection 50 ml) was used. And the main left pulmonary artery was treated with the Angiojet system for 20 s, and the main right pulmonary artery was treated with the Angiojet system for 15 s (Figure 2). However, this treatment was finished because of bradyarrhythmia, and bradyarrhythmia disappeared after catheter withdrawal. And we placed the catheter in the inferior vena cava; intravascular thrombolysis by urokinase (100 wiu/day, 1 day) was done after being back in the ward. And low molecular weight heparin was used in hospitalization, and rivaroxaban was used after discharge. In addition, whole blood count analysis revealed a white blood cell count of 11.5 x 109/l (reference range 3.5-9.5 x 109/l), haemoglobin level of 140 g/l (reference range 115-150 g/l), hematocrit level of 41% (reference range 40-50%), and a platelet count of 161 x 109/l (reference range 125-350 x 109/l) on September 1. The results of NT-proBNP and creatine were 801 pg/ml (reference range 0-1800 pg/ml) and 110 mumol/l (reference range 20-98 mumol/l) on September 9, respectively. And echocardiogram showed decreased right ventricular transverse diameter (42 mm), normal left ventricular end diastolic anteroposterior diameter (52 mm), and higher pulmonary artery pressure (72 mmHg) on September 11.