Reduction of left ventricular pressure gradient due to cibenzoline therapy in a 16-year-old girl with hypertrophic obstructive cardiomyopathy.

A 13-year-old girl was referred for closer examination of electrocardiographic abnormalities. She had a Levine 2/6 systolic murmur (SM) and a fourth heart sound. Electrocardiography findings showed poor R progression from V1 to V4 and negative T waves in the II, III, and aVF leads. Approximately 3.2 years later, her SM increased to Levine 3-4/6. Echocardiography indicated mitral regurgitation and left ventricular pressure gradient (LVPG) of 18.5 mmHg, together with a notch on the systolic wave in the apexcardiogram. We concluded that the electrocardiographic abnormalities were caused by hypertrophic cardiomyopathy. Approximately 6 months later, her SM further increased to Levine 4-5/6, and the voltage on the electrocardiogram increased. In carotid pulse tracing, steep upstroke and deflated percussion wave due to mitral regurgitation were noted. The LVPG was approximately 102 mmHg, and systolic anterior movement was confirmed. After the oral administration of 200 mg of cibenzoline, the LVPG decreased to approximately 48 mmHg. Subsequently, 300 mg/day of cibenzoline was administered. The LVPG further decreased, and her symptoms improved. Learning objectives: Clinical symptoms and left ventricular pressure gradient decrease can be ameliorated by cibenzoline therapy in patients with hypertrophic obstructive cardiomyopathy. This finding applies not only to adult patients but also to teen-aged patients.