BACKGROUND: Mutations of mitochondrial DNA have been demonstrated as causes of human mitochondrial diseases. While these disorders typically involve multiple organs, the effect of mitochondrial mutations on the heart has not been systematically studied. METHODS AND RESULTS: We studied mitochondrial mutations and cardiac changes in 17 patients with Kearns-Sayre syndrome; ocular myopathy; myoclonus epilepsy with ragged red fibers (MERRF); and mitochondrial myopathy, encephalopathy, lactic acidosis, and strokelike episodes (MELAS). Cardiac involvement was evaluated by chest radiograph, ECG, His-bundle electrogram, and echocardiogram. All 3 patients with Kearns-Sayre syndrome had large deletions of mitochondrial DNA and disturbances in cardiac conduction. ECG abnormalities were found in 2 of 6 patients with ocular myopathy who showed large deletions of mitochondrial DNA. All 3 patients with MERRF had an A-to-G mutation at nucleotide position 8344; 2 had cardiomegaly, asymmetrical septal hypertrophy, and diffuse hypokinesis of the left ventricle. One patient with asymmetrical septal hypertrophy developed dilated cardiomyopathy 2 years later. All 5 patients with MELAS had an A-to-G mutation at nucleotide position 3243, and 2 had symmetrical left ventricular hypertrophy with or without abnormal wall motion. CONCLUSIONS: The clinical features of cardiac involvement in mitochondrial diseases vary in the different subgroups of these disorders. Particular mitochondrial mutations can cause characteristic cardiac abnormalities.
BACKGROUND: Mutations of mitochondrial DNA have been demonstrated as causes of humanmitochondrial diseases. While these disorders typically involve multiple organs, the effect of mitochondrial mutations on the heart has not been systematically studied. METHODS AND RESULTS: We studied mitochondrial mutations and cardiac changes in 17 patients with Kearns-Sayre syndrome; ocular myopathy; myoclonus epilepsy with ragged red fibers (MERRF); and mitochondrial myopathy, encephalopathy, lactic acidosis, and strokelike episodes (MELAS). Cardiac involvement was evaluated by chest radiograph, ECG, His-bundle electrogram, and echocardiogram. All 3 patients with Kearns-Sayre syndrome had large deletions of mitochondrial DNA and disturbances in cardiac conduction. ECG abnormalities were found in 2 of 6 patients with ocular myopathy who showed large deletions of mitochondrial DNA. All 3 patients with MERRF had an A-to-G mutation at nucleotide position 8344; 2 had cardiomegaly, asymmetrical septal hypertrophy, and diffuse hypokinesis of the left ventricle. One patient with asymmetrical septal hypertrophy developed dilated cardiomyopathy 2 years later. All 5 patients with MELAS had an A-to-G mutation at nucleotide position 3243, and 2 had symmetrical left ventricular hypertrophy with or without abnormal wall motion. CONCLUSIONS: The clinical features of cardiac involvement in mitochondrial diseases vary in the different subgroups of these disorders. Particular mitochondrial mutations can cause characteristic cardiac abnormalities.
Authors: Ali Yilmaz; Hans-Jürgen Gdynia; Matthias Ponfick; Sabine Rösch; Alfred Lindner; Albert C Ludolph; Udo Sechtem Journal: Clin Res Cardiol Date: 2011-12-06 Impact factor: 5.460
Authors: Hideo Makimura; Takara L Stanley; Noelle Sun; Jean M Connelly; Linda C Hemphill; Mirko I Hrovat; David M Systrom; Steven K Grinspoon Journal: Atherosclerosis Date: 2010-12-05 Impact factor: 5.162