title: Left ventricular wall thickness and the presence of asymmetric hypertrophy in healthy young army recruits: data from the LARGE heart study.
abstract: BACKGROUND
  To use cardiovascular magnetic resonance to investigate left ventricular wall thickness and the presence of asymmetrical hypertrophy in young army recruits before and after a period of intense exercise training.
  
  
  RESULTS
  Using cardiovascular magnetic resonance, the left ventricular wall thickness was measured in all 17 segments and a normal range was calculated for each. The prevalence of asymmetrical wall thickening was assessed before and after training and defined by a ventricular wall thickness ≥13.0 mm that was >1.5× the thickness of the opposing myocardial segment. Five hundred forty-one men (mean age, 20±2 years) were recruited, 309 underwent repeat scanning. Considerable variation in wall thickness was observed across the ventricle with progressive thickening on moving from the apex to base (P<0.001) and in the basal and midcavity septum compared with the lateral wall (11.0±1.4 versus 10.1±1.3 mm; P<0.001). Twenty-three percent had a maximal wall thickness ≥13.0 mm, whereas the prevalence of asymmetrical wall thickening increased from 2.2% to 10% after the exercise-training program. In those who developed asymmetry, the wall thickness/diastolic volume ration remained normal (0.09±0.02 mm⋅m(2)⋅mL(-1)), indicative of a remodeling response to exercise.
  
  
  CONCLUSIONS
  In a cohort of healthy young white men, we have demonstrated that wall thickness frequently measures ≥13.0 mm and that asymmetrical wall thickening is common and can develop as part of the physiological response to exercise. A diagnosis of hypertrophic cardiomyopathy in young athletic men should, therefore, not be made purely on the basis of regional wall thickening.
authors: Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, United Kingdom.
authors: Phong T
authors: PT
authors: Lee
authors: Marc R
authors: MR
authors: Dweck
authors: Sparsh
authors: S
authors: Prasher
authors: Anoop
authors: A
authors: Shah
authors: Steve E
authors: SE
authors: Humphries
authors: Dudley J
authors: DJ
authors: Pennell
authors: Hugh E
authors: HE
authors: Montgomery
authors: John R
authors: JR
authors: Payne
mesh_terms: D000293:Adolescent; D000367:Age Factors; D000704:Analysis of Variance; D059267:Cardiomegaly, Exercise-Induced; D002312:Cardiomyopathy, Hypertrophic / Q000175:diagnosis* / Q000208:ethnology / Q000473:pathology / Q000503:physiopathology; D003937:Diagnosis, Differential; D015444:Exercise; D006352:Heart Ventricles / Q000473:pathology*; D006801:Humans; D017379:Hypertrophy, Left Ventricular / Q000175:diagnosis* / Q000208:ethnology / Q000473:pathology / Q000503:physiopathology; D008279:Magnetic Resonance Imaging; D008297:Male; D008889:Military Personnel; D015588:Observer Variation; D011237:Predictive Value of Tests; D011446:Prospective Studies; D015203:Reproducibility of Results; D006113:United Kingdom / Q000453:epidemiology; D044465:White People; D055815:Young Adult