title: The microvascular effects of insulin resistance and diabetes on cardiac structure, function, and perfusion: a cardiovascular magnetic resonance study.
abstract: OBJECTIVE
  Type 2 diabetes mellitus is an independent risk factor for the development of heart failure. To better understand the mechanism by which this occurs, we investigated cardiac structure, function, and perfusion in patients with and without diabetes.
  
  
  RESULTS
  Sixty-five patients with no stenosis >30% on invasive coronary angiography were categorized into diabetes (19) and non-diabetes (46) which was further categorized into prediabetes (30) and controls (16) according to the American Diabetes Association guidelines. Each patient underwent comprehensive cardiovascular magnetic resonance assessment. Left-ventricular (LV) mass, relative wall mass (RWM), Lagrangian circumferential strain, LV torsion, and myocardial perfusion reserve (MPR) were calculated. LV mass was higher in diabetics than non-diabetics (112.8 ± 39.7 vs. 91.5 ± 21.3 g, P = 0.01) and in diabetics than prediabetics (112.8 ± 39.7 vs. 90.3 ± 18.7 g, P = 0.02). LV torsion angle was higher in diabetics than non-diabetics (9.65 ± 1.90 vs. 8.59 ± 1.91°, P = 0.047), and MPR was lower in diabetics than non-diabetics (2.10 ± 0.76 vs. 2.84 ± 1.25 mL/g/min, P = 0.01). There was significant correlation between MPR and early diastolic strain rate (r = -0.310, P = 0.01) and LV torsion (r = -0.306, P = 0.01). In multivariable linear regression analysis, non-diabetics waist-hip ratio, but not body mass index, had a significant association with RWM (Beta = 0.34, P = 0.02).
  
  
  CONCLUSIONS
  Patients with diabetes have increased LV mass, LV torsion, and decreased MPR. There is a significant association between decreased MPR and increased LV torsion suggesting a possible mechanistic link between microvascular disease and cardiac dysfunction in diabetes.
authors.affiliation: Multidisciplinary Cardiovascular Research Centre & Leeds Institute of Genetics, Health and Therapeutics, University of Leeds, Leeds LS2 9JT, UK Department of Cardiology and Internal Medicine, Tripoli Medical Centre, Faculty of Medicine, University of Tripoli, Tripoli, Libya.
authors.forename: Abdulghani M
authors.initials: AM
authors.lastname: Larghat
authors.affiliation: Multidisciplinary Cardiovascular Research Centre & Leeds Institute of Genetics, Health and Therapeutics, University of Leeds, Leeds LS2 9JT, UK.
authors.forename: Peter P
authors.initials: PP
authors.lastname: Swoboda
authors.affiliation: Division of Medical Physics, University of Leeds, Leeds, UK.
authors.forename: John D
authors.initials: JD
authors.lastname: Biglands
authors.affiliation: Multidisciplinary Cardiovascular Research Centre & Leeds Institute of Genetics, Health and Therapeutics, University of Leeds, Leeds LS2 9JT, UK.
authors.forename: Mark T
authors.initials: MT
authors.lastname: Kearney
authors.affiliation: Multidisciplinary Cardiovascular Research Centre & Leeds Institute of Genetics, Health and Therapeutics, University of Leeds, Leeds LS2 9JT, UK.
authors.forename: John P
authors.initials: JP
authors.lastname: Greenwood
authors.affiliation: Multidisciplinary Cardiovascular Research Centre & Leeds Institute of Genetics, Health and Therapeutics, University of Leeds, Leeds LS2 9JT, UK s.plein@leeds.ac.uk.
authors.forename: Sven
authors.initials: S
authors.lastname: Plein
mesh_terms: D000368:Aged; D003924:Diabetes Mellitus, Type 2 / Q000503:physiopathology*; D005260:Female; D006333:Heart Failure / Q000175:diagnosis*; D006801:Humans; D007333:Insulin Resistance; D019028:Magnetic Resonance Imaging, Cine / Q000379:methods*; D008297:Male; D055806:Microvessels / Q000503:physiopathology; D008875:Middle Aged; D011237:Predictive Value of Tests; D011446:Prospective Studies; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D018487:Ventricular Dysfunction, Left / Q000503:physiopathology*
keywords: Cardiovascular magnetic resonance; Diabetes; Myocardial perfusion reserve; Prediabetes; Strain; Tagging