Case Report
An 81-year-old woman was admitted to the hospital with progressive dyspnea and syncope. Two days before the present admission, she had shortness of breath and a dry cough, and she presented at the emergency room for further evaluation. She also reported left lower extremity pain and swelling. On examination, she was in respiratory distress, with tachypnea (27 breaths/min), blood pressure of 85/56 mmHg, tachycardia (138 beats/min), and body temperature measuring 36.8°C. Arterial blood gas analysis under oxygen 2 L/min revealed pH of 7.286; pO2, 66 mmHg; pCO2, 37 mmHg, and bicarbonate 20.3 mmol/L. Laboratory results included a D-dimer level of 9.488 μg/mL and an elevated high sensitive troponin I level of 247.10 ng/mL. Her electrocardiogram showed evidence of a right bundle branch block, sinus tachycardia, and nonspecific ST-T abnormality. Chest X-ray did not show any remarkable findings. However, transthoracic echocardiography showed (TTE) showed a massive right ventricular and mobile right atrial thrombus and also right sided enlargement and flattening of the interventricular septum (Figure 1A, B). Systolic pulmonary artery pressure was calculated as 65 mmHg. Subsequent chest computed tomography scan disclosed a pulmonary thromboembolism in both pulmonary arteries (Figure 2A). Under the diagnosis of an intracardiac mass and suspicious thrombus formation in the right atrium with acute PE, the patient was admitted to the cardiac intensive care unit for further treatment.
The patient was immediately administered continuous, high-dose intravenous heparin for anticoagulation and she was placed on intravenous inotropes. Cardiothoracic surgeons were consulted regarding open pulmonary embolectomy. The risks and benefits of both pulmonary embolectomy and catheter directed thrombolysis (CDT) were extensively discussed with the patient and her family. Because the patient’s age made her a high-risk surgical candidate, the decision was made to proceed with CDT.
After informed consent was obtained, the patient was brought to the cardiac catheterization laboratory. A right heart catheterization was performed using a 6 Fr sheath placed in the right common femoral vein (CFV). Pulmonary angiogram was performed and it showed a subtotal occlusion in the right main pulmonary artery (PA) and occlusive thrombus in the left PA branches. The EKOS catheter (30 cm) was then placed from the junction of the inferior vena cava into the right main PA extending into the thrombus (Figure 2B). Another EKOS catheter was then implanted from a second venous sheath placed in the left CFV into the left PA.
A total of 2 mg Actilyse (Alteplase, Boehringer Ingelheim GmbH&-Co, Ingelheim, Germany) bolus were administered from catheters then 1mg/h tPA infusion was started for each lung for a total of 18 hours. (total of 38 mg tPA for both lungs). A total of 1000 units of heparin/h was infused in each venous sheath for the duration of tPA infusion.
Following 18 hours of tPA infusion, she was feeling quite better with her heart rate 95 beats/min and systolic blood pressure 125 mmHg. Her respiratory rate was 17/min, and oxygen saturation was 96%. PA pressure decreased to 45 mmHg and a progressive decrease in the size of thrombus was detected in serial echocardiographic examinations. The echocardiographic examination also showed that the thrombus in the right ventricular apex and the mobile thrombus in the right atrium had totally disappeared (Figure. 3A, B).
Forty-eight hours after the procedure, the right side of the heart had become normal in size, and pulmonary systolic pressure had decreased to 30 mmHg and interventricular septal motion significantly improved. Within 2 days, computed tomography angiography was repeated. The intracardiac thrombus and massive PE had both completely resolved (Figure 2C). The patient was discharged from the hospital 5 days after initial presentation with instructions to take oral anticoagulants. At her 3-month follow-up examination, she remained asymptomatic.