title: Regional and global ventricular systolic function in isolated ventricular non-compaction: pathophysiological insights from magnetic resonance imaging.
abstract: BACKGROUND
  Isolated ventricular non-compaction (IVNC) is frequently, but not invariably, associated with left ventricular (LV) systolic dysfunction. Factors impacting on regional and global LV function are unknown. The aim of the study was to apply magnetic resonance imaging (MRI) to evaluate the impact of extent and severity of ventricular non-compaction on LV systolic function in patients with IVNC.
  
  
  METHODS
  Sixteen adult patients with IVNC as defined by previously validated MRI criteria [ratio between end-diastolic thickness of non-compacted and compacted myocardium (NC/C ratio)> 2.3 in ≥ 1 LV segment] were enrolled. Short-axis cine images were employed for analysis. Applying a 16-segment LV model, regional systolic performance was assessed qualitatively (wall motion score, WMS; 1 = normal, 2 = mild hypokinesia, 3 = moderate-to-severe hypokinesia, and 4 = a/dyskinesia) as well as quantitatively [fractional wall thickening, FWT (%)=100 × (end-diastolic wall thickness-end-systolic wall thickness)/end-diastolic wall thickness)].
  
  
  RESULTS
  Mean LV ejection fraction was 43.8 ± 15.4% (range, 17-68%). Regional disease severity, as expressed by the NC/C ratio, revealed a significant correlation with WMS (r=0.26; p=0.018) and FWT (r=-0.30; p=0.006). The total number of non-compacted segments/patient (NoNC) as an index of disease extent was a significant independent correlate of LV ejection fraction by multivariate regression analysis (β=-5.24; p=0.038) and an excellent predictor of global LV dysfunction (ROC analysis, AUC=0.98; p<0.0001).
  
  
  CONCLUSIONS
  In patients with IVNC, disease severity correlates with the degree of LV dysfunction at a regional level. The extent of myocardial non-compaction is an independent predictor of global LV dysfunction.
authors.affiliation: Department of Clinical Medicine, Cardiovascular and Immunological Sciences, Federico II University, Naples, Italy. Santo.Dellegrottaglie@mssm.edu
authors.forename: Santo
authors.initials: S
authors.lastname: Dellegrottaglie
authors.forename: Patrizia
authors.initials: P
authors.lastname: Pedrotti
authors.forename: Alberto
authors.initials: A
authors.lastname: Roghi
authors.forename: Stefano
authors.initials: S
authors.lastname: Pedretti
authors.forename: Massimo
authors.initials: M
authors.lastname: Chiariello
authors.forename: Pasquale
authors.initials: P
authors.lastname: Perrone-Filardi
mesh_terms: D000328:Adult; D000368:Aged; D057791:Cardiac Imaging Techniques / Q000379:methods* / Q000592:standards / Q000706:statistics & numerical data; D005260:Female; D005682:Gadolinium; D006801:Humans; D056830:Isolated Noncompaction of the Ventricular Myocardium / Q000473:pathology* / Q000503:physiopathology*; D008279:Magnetic Resonance Imaging / Q000379:methods* / Q000592:standards / Q000706:statistics & numerical data; D008297:Male; D008875:Middle Aged; D015588:Observer Variation; D011237:Predictive Value of Tests; D012372:ROC Curve; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012720:Severity of Illness Index; D013318:Stroke Volume / Q000502:physiology; D013599:Systole / Q000502:physiology*; D016277:Ventricular Function, Left / Q000502:physiology; D055815:Young Adult
chemical_list: D005682:Gadolinium