title: Is 2D speckle tracking echocardiography useful for detecting and monitoring myocardial dysfunction in adult m.3243A>G carriers? - a retrospective pilot study.
abstract: Cardiomyopathy is a common complication of mitochondrial disorders, associated with increased mortality. Two dimensional speckle tracking echocardiography (2DSTE) can be used to quantify myocardial deformation. Here, we aimed to determine the usefulness of 2DSTE in detecting and monitoring subtle changes in myocardial dysfunction in carriers of the 3243A>G mutation in mitochondrial DNA.
  
  
  
  In this retrospective pilot study, 30 symptomatic and asymptomatic carriers of the mitochondrial 3243A>G mutation of whom two subsequent echocardiograms were available were included. We measured longitudinal, circumferential and radial strain using 2DSTE. Results were compared to published reference values.
  
  
  
  Speckle tracking was feasible in 90 % of the patients for longitudinal strain. Circumferential and radial strain showed low face validity (low number of images with sufficient quality; suboptimal tracking) and were therefore rejected for further analysis. Global longitudinal strain showed good face validity, and was abnormal in 56-70 % (depending on reference values used) of the carriers (n = 27). Reproducibility was good (mean difference of 0.83 for inter- and 0.40 for intra-rater reproducibility; ICC 0.78 and 0.89, respectively). The difference between the first and the second measurement exceeded the measurement variance in 39 % of the cases (n = 23; feasibility of follow-up 77 %).
  
  
  
  Even in data collected as part of clinical care, two-dimensional strain echocardiography seems a feasible method to detect and monitor subtle changes in longitudinal myocardial deformation in adult carriers of the mitochondrial 3243A>G mutation. Based on our data and the reported accuracy of global longitudinal strain in other studies, we suggest the use of global longitudinal strain in a prospective follow-up or intervention study.
authors.affiliation: Radboud Centre for Mitochondrial Medicine, Radboud University Nijmegen Medical Centre, Geert Grooteplein 10, 6500 HB, PO BOX 9101, Nijmegen, The Netherlands. Saskia.koene@radboudumc.nl.
authors.forename: S
authors.initials: S
authors.lastname: Koene
authors.affiliation: Department of Cardiology, Radboudumc, Nijmegen, The Netherlands.
authors.forename: J
authors.initials: J
authors.lastname: Timmermans
authors.affiliation: Clinical Physics Laboratory, Department of Radiology, Radboudumc, Nijmegen, The Netherlands.
authors.forename: G
authors.initials: G
authors.lastname: Weijers
authors.affiliation: Radboud Centre for Mitochondrial Medicine, Radboud University Nijmegen Medical Centre, Geert Grooteplein 10, 6500 HB, PO BOX 9101, Nijmegen, The Netherlands.
authors.forename: P
authors.initials: P
authors.lastname: de Laat
authors.affiliation: Clinical Physics Laboratory, Department of Radiology, Radboudumc, Nijmegen, The Netherlands.
authors.forename: C L
authors.initials: CL
authors.lastname: de Korte
authors.affiliation: Radboud Centre for Mitochondrial Medicine, Radboud University Nijmegen Medical Centre, Geert Grooteplein 10, 6500 HB, PO BOX 9101, Nijmegen, The Netherlands.
authors.forename: J A M
authors.initials: JA
authors.lastname: Smeitink
authors.affiliation: Radboud Centre for Mitochondrial Medicine, Radboud University Nijmegen Medical Centre, Geert Grooteplein 10, 6500 HB, PO BOX 9101, Nijmegen, The Netherlands.|Department of Internal Medicine, Radboudumc, Nijmegen, The Netherlands.
authors.forename: M C H
authors.initials: MC
authors.lastname: Janssen
authors.affiliation: Department of Paediatrics, Paediatric Cardiology Unit, Tel-Aviv Sourasky Medical Centre, Tel Aviv, Israel.|Children's Heart Center, Radboudumc, Amalia Children's Hospital, Nijmegen, The Netherlands.
authors.forename: L
authors.initials: L
authors.lastname: Kapusta
mesh_terms: D000293:Adolescent; D000328:Adult; D009202:Cardiomyopathies / Q000235:genetics* / Q000473:pathology*; D004272:DNA, Mitochondrial / Q000235:genetics; D004452:Echocardiography / Q000379:methods; D005260:Female; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D009154:Mutation / Q000235:genetics; D009206:Myocardium / Q000473:pathology*; D010865:Pilot Projects; D015203:Reproducibility of Results; D012189:Retrospective Studies; D055815:Young Adult
chemical_list: D004272:DNA, Mitochondrial