PMC4724951_01
Echocardiographic findings. At birth, tumors were located on the postero-septal wall of the left ventricle (a, arrow), right ventricular outflow (b, arrow), and intraventricular septum (b, arrowhead) at birth. At the age of 23 months, 2D echocardiography disclosed an enlarged left ventricle (c), and M-mode echocardiography revealed poor left ventricular wall contraction (d)
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Fig1
Multiple intramural cardiac tumors of 5-25 mm in diameter were found by transthoracic echocardiography (Fig. 1a, b). Echocardiography revealed cardiac dilatation and diffuse hypokinesis, LVDd of 45.2 mm (Z-score: 3.0), and LVFS of 15 % (Fig. 1c). Surprisingly, his cardiac tumors had diminished in size and were recognizable as a small bright area in the posterior mitral valve (Fig. 1d).
a, b Changes in cardiac function before and during treatment with carvedilol. BNP, Brain natriuretic peptide; LVDd, Left ventricular end-diastolic diameter; LVFS, Left ventricular fractional shortening; HR: Heart rate; PSVC, Premature supraventricular contraction; PVC, Premature ventricular contraction
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Fig2
Mexiletine treatment was commenced at 1 month of age (Fig. 2a). Although frequent PSVC persisted, the boy's mean HR gradually decreased and the incidence of PVC and its short run became markedly diminished (Fig. 2a). The abnormal values of LVFS and LVDd persisted for 1 year after the initiation of carvedilol treatment, but both parameters eventually improved to normal levels (34 % and 35.8 mm [Z-score: 0.8], respectively) by the age of 4 years (Fig. 2b).
Electrocardiography findings. Twelve-lead electrocardiography (ECG) revealed irregular tachycardia (139 bpm) and sporadic PSVC without ST abnormality or wide QRS duration
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Fig3
Twelve-lead ECG revealed irregular tachycardia (139 bpm) and sporadic PSVC without ST abnormality or wide QRS duration (Fig. 3).