Combination of mitochondrial myopathy and biventricular hypertrabeculation/noncompaction

Left ventricular hypertrabeculation/noncompaction (LVHT/LVNC), characterized by prominent trabeculations and intertrabecular recesses within the left ventricle, is a cardiac abnormality of unclear etiology. Although the left ventricle is the most commonly affected site, a few cases of biventricular involvement have also been reported. We report a 31-year-old woman who presented with mild cardiac symptoms and progressive bilateral limb muscle weakness following exercise which she had also been experiencing for about 5 years. Abnormal serum levels of creatine kinase, lactic acid and pyruvic acid, combined with the results of modified lactate stress test, needle EMG and muscle biopsy indicated that she had mitochondrial myopathy. The transthoracic echocardiography, together with magnetic resonance imaging (MRI), revealed biventricular hypertrabeculation.