Kieren G. Hollingsworth1, Grainne S. Gorman2, Michael I. Trenell1, Robert McFarland2, Robert W. Taylor2, Douglass M. Turnbull2, Guy A. MacGowan3, Patrick F. Chinnery4, Andrew M. Blamire1
1Newcastle Magnetic Resonance Centre, Newcastle University, Newcastle upon Tyne, Tyne & Wear, United Kingdom; 2Mitochondrial Research Group, Newcastle University, Newcastle upon Tyne, Tyne & Wear, United Kingdom; 3Department of Cardiology, Freeman Hospital, Newcastle upon Tyne, Tyne & Wear, United Kingdom; 4Institute of Human Genetics, Newcastle University, Newcastle upon Tyne, Tyne & Wear, United Kingdom
Cardiomyopathy causes morbidity and mortality in m3243A>G mutation carriers. It remains controversial how early cardiac hypertrophy and dysfunction occur. 10 m3243A>G mutation carriers and 16 age- and gender-matched control subjects were recruited: anatomical MRI allowed assessment of left ventricular size and systolic function: cardiac tagging was used to assess torsion and regional myocardial strains. Mutant mtDNA load was measured by muscle biopsy. Concentric left ventricular hypertrophy was found in the absence of systemic hypertension, and LV index was found to discriminate hypertrophy better than LV mass. Mutation carriers had a re-orientation of myocardial strains which correlated with mutation load.