The patient was treated with bosentan, furosemide, and digoxin, and 6-min walk testing and right heart catheterization were repeated 9 months later (Table 1). In anticipation of surgical resection of the hepatic echinococcal cyst, treatment with continuous IV epoprostenol was initiated, and that with bosentan was continued. At the time of surgery, hemodynamics were improved (Table 1). IV milrinone, dobutamine, vasopressin, norepinephrine, and inhaled nitric oxide were subsequently administered to maximize the cardiac index and preserve systemic perfusion. Intraoperatively, the cyst was found to encase the right hepatic vein, and the cyst cavity was open to the inferior vena cava (IVC) lumen (Fig 3
). The cyst and a portion of the IVC were excised with polyester (Dacron; DuPont; Wilmington, DE) graft reconstruction, employing venovenous bypass. The patient was discharged from the surgical ICU 3 days after undergoing surgery, and from the hospital after 4 weeks. After repeat right heart catheterization showed significant hemodynamic improvement (Table 1), therapy with sildenafil was begun. The patient was then weaned from epoprostenol over a 3-week period, and epoprostenol therapy was stopped during an inpatient hospital admission. After hospital discharge, the patient was maintained on therapy with bosentan and sildenafil, and was able to return to work. One year after undergoing surgery, transthoracic echocardiography did not show significant changes, whereas the 6-min walk test distance remained substantially increased from baseline.