[Effective milrinone therapy to a Duchenne muscular dystrophy patient with advanced congestive heart failure]

We experienced a Duchenne muscular dystrophy (DMD) patient with severe congestive heart failure (CHF) successfully treated with milrinone. He had been diagnosed as having CHF since 24 years of age when he began to have mechanical ventilation with a nasal mask at home. Although angiotensin converting enzyme (ACE) inhibitor was effective for his CHF, cardiac function worsened year by year. Respiratory infection triggered the exacerbation of CHF at the end of 1997 (27 years old). On admission to our hospital on January 7, 1998, PaO2 was 48 mmHg and cardiothoracic ratio (CTR) was 62%. Both ventricles were dilated and ventricular wall motility was markedly reduced on ultrasonocardiography. Ejection fraction of the left ventricle (LVEF) was 5%. Serum brain natriuretic peptide (BNP) was 760 pg/ml. Continuous intravenous infusion of milrinone was started on January 8 at the rate of 0.25-0.35 microgram/kg/min. His general condition improved and LVEF increased up to 15% on January 27. No serious side effects were observed. Even after milrinone withdrawal, his cardiac condition remained stable until the end of February 1998. Temporary deteriorated CHF due to urinary tract infection was successfully treated by chemotherapy and milrinone. Subsequently he was discharged on March 13 and could stay in his home for 7 weeks uneventfully with milrinone infusion therapy. When he was readmitted to the hospital for evaluation of CHF on April 30, CTR was 44%, LVEF was 20% and BNP was 44 pg/ml. CHF is one of the life threatening complications for DMD. Although catecholamine is a well utilized agent for advanced CHF, it has limited effect in DMD, because beta receptors are down-regulated due to long-lasting cardiac dysfunction. Increased heart rate and arrhytmia are also serious problems during catecholamine therapy. Milrinone is a type III phosphodiesterase inhibitor having inotropic and vasodilatic actions with modest increase of heart rate and little torelance. Milrinone is probably effective in improving CHF of DMD and has less side effects as compared to catecholamine. We concluded that milrinone might improve quality of lives of DMD patients with advanced CHF, although further cumultative studies are necessary to confirm its effectiveness and safety.