Medical Treatment for an Adult Patient With Eisenmenger Syndrome

Previous studies examining the use of pulmonary arterial hypertension (PAH) drugs in patients with Eisenmenger syndrome (ES) have shown that it may have beneficial effects in some patients with ES; however, experience with additional cases is necessary to confirm its efficacy and appropriate clinical use. We herein report our experience of an adult patient with ES who benefitted from treatment with PAH drugs. A 32-year-old Japanese man with severe ES induced by a ventricular septal defect associated with Down syndrome began treatment with bosentan at 62.5 mg. Eleven months later, he was admitted for tadalafil (40 mg) add-on therapy because his 6-minute walking distance and brain natriuretic peptide (BNP) level had not improved and his hepatic enzyme levels had increased. However, marked hypotension developed, and the tadalafil dose was decreased. His BNP level subsequently increased, so the bosentan dose was increased to 125 mg. The bosentan was then abruptly stopped because of a low platelet count and high liver enzyme levels. Ambrisentan was then administered for these side effects, but because severe dyspnea developed, the bosentan was started again at 62.5 mg. This resulted in immediate clinical improvement. The patient was finally switched to ambrisentan (5 mg), which was well tolerated. The findings in this particular case show that although it should be used with caution, bosentan may be beneficial in select patients with ES. In addition, ambrisentan may be considered as first-line treatment in some patients as long as liver enzymes and platelets are carefully monitored.