Late in the course, the usual signs and electrocardiographic findings of pulmonary hypertension, right heart failure, and right ventricular hypertrophy are present. Transthoracic echocardiography is useful for estimating pulmonary artery systolic pressure and excluding other cardiac causes of pulmonary hypertension and right heart failure. Transesophageal echocardiography rarely may visualize thrombus with the right main pulmonary artery or right heart chambers. However, the extent of the perfusion deficit may underestimate the amount of central pulmonary artery obstruction and should not be used to exclude patients as candidates for surgery. Only thrombus within segmental or larger pulmonary arteries is amenable to surgical resection.
Most authorities recommend placement of an inferior vena cava filter preoperatively.
Surgical candidates should be referred to a medical center with a dedicated medical and surgical team who are highly experienced in pulmonary thromboendarterectomy surgical technique and postoperative care. A median sternotomy approach is used to provide bilateral exposure. A special heart cooling jacket is applied to avoid injury to the phrenic nerves. A careful and complete thromboendarterectomy is required for optimal results. While an atrial sepal defect or patent foramen ovale is closed routinely, tricuspid valve repair or replacement due to severe tricuspid regurgitation is unnecessary.