title: ECG strain pattern in hypertension is associated with myocardial cellular expansion and diffuse interstitial fibrosis: a multi-parametric cardiac magnetic resonance study.
abstract: OBJECTIVE
  In hypertension, the presence of left ventricular (LV) strain pattern on 12-lead electrocardiogram (ECG) carries adverse cardiovascular prognosis. The underlying mechanisms are poorly understood. We investigated whether hypertensive ECG strain is associated with myocardial interstitial fibrosis and impaired myocardial strain, assessed by multi-parametric cardiac magnetic resonance (CMR).
  
  
  RESULTS
  A total of 100 hypertensive patients [50 ± 14 years, male: 58%, office systolic blood pressure (SBP): 170 ± 30 mmHg, office diastolic blood pressure (DBP): 97 ± 14 mmHg) underwent ECG and 1.5T CMR and were compared with 25 normotensive controls (46 ± 14 years, 60% male, SBP: 124 ± 8 mmHg, DBP: 76 ± 7 mmHg). Native T1 and extracellular volume fraction (ECV) were calculated with the modified look-locker inversion-recovery sequence. Myocardial strain values were estimated with voxel-tracking software. ECG strain (n = 20) was associated with significantly higher indexed LV mass (LVM) (119 ± 32 vs. 80 ± 17 g/m2, P < 0.05) and ECV (30 ± 4 vs. 27 ± 3%, P < 0.05) compared with hypertensive subjects without ECG strain (n = 80). ECG strain subjects had significantly impaired circumferential strain compared with hypertensive subjects without ECG strain and controls (-15.2 ± 4.7 vs. -17.0 ± 3.3 vs. -17.3 ± 2.4%, P < 0.05, respectively). In subgroup analysis, comparing ECG strain subjects to hypertensive subjects with elevated LVM but no ECG strain, a significantly higher ECV (30 ± 4 vs. 28 ± 3%, P < 0.05) was still observed. Indexed LVM was the only variable independently associated with ECG strain in multivariate logistic regression analysis [odds ratio (95th confidence interval): 1.07 (1.02-1.12), P < 0.05).
  
  
  CONCLUSIONS
  In hypertension, ECG strain is a marker of advanced LVH associated with increased interstitial fibrosis and associated with significant myocardial circumferential strain impairment.
authors.affiliation: NIHR Bristol Cardiovascular Biomedical Research Unit, Bristol Heart Institute, University Hospitals Bristol NHS Foundation Trust, Upper Maudlin Street, Bristol BS2 8HW, UK.|School of Physiology, Pharmacology and Neuroscience, Faculty of Biomedical Sciences, University of Bristol, Bristol, UK.
authors.forename: Jonathan C L
authors.initials: JC
authors.lastname: Rodrigues
authors.affiliation: NIHR Bristol Cardiovascular Biomedical Research Unit, Bristol Heart Institute, University Hospitals Bristol NHS Foundation Trust, Upper Maudlin Street, Bristol BS2 8HW, UK.|Department of Surgical, Microsurgical and Medical Sciences, Institute of Radiology, University of Sassari, Sassari, Italy.
authors.forename: Antonio Matteo
authors.initials: AM
authors.lastname: Amadu
authors.affiliation: NIHR Bristol Cardiovascular Biomedical Research Unit, Bristol Heart Institute, University Hospitals Bristol NHS Foundation Trust, Upper Maudlin Street, Bristol BS2 8HW, UK.|Department of Cardiology, Bristol Heart Institute, University Hospitals Bristol NHS Foundation Trust, Bristol, UK.
authors.forename: Amardeep
authors.initials: A
authors.lastname: Ghosh Dastidar
authors.affiliation: Severn Postgraduate Medical Education Foundation School, NHS Health Education South West, Bristol, UK.
authors.forename: Bethannie
authors.initials: B
authors.lastname: McIntyre
authors.affiliation: NIHR Bristol Cardiovascular Biomedical Research Unit, Bristol Heart Institute, University Hospitals Bristol NHS Foundation Trust, Upper Maudlin Street, Bristol BS2 8HW, UK.|Department of Cardiology, University Hospital of Wales, Cardiff, UK.
authors.forename: Gergley V
authors.initials: GV
authors.lastname: Szantho
authors.affiliation: NIHR Bristol Cardiovascular Biomedical Research Unit, Bristol Heart Institute, University Hospitals Bristol NHS Foundation Trust, Upper Maudlin Street, Bristol BS2 8HW, UK.|Department of Radiology, Bristol Royal Infirmary, University Hospitals Bristol NHS Foundation Trust, Bristol, UK.
authors.forename: Stephen
authors.initials: S
authors.lastname: Lyen
authors.affiliation: Department of General Medicine, Bristol Royal Infirmary, University Hospitals Bristol NHS Foundation Trust, Bristol, UK.
authors.forename: Cattleya
authors.initials: C
authors.lastname: Godsave
authors.affiliation: CardioNomics Research Group, Clinical Research and Imaging Centre (CRIC) Bristol, Bristol Heart Institute, University Hospitals Bristol NHS Foundation Trust, Upper Maudlin Street, Bristol BS2 8HW.
authors.forename: Laura E K
authors.initials: LE
authors.lastname: Ratcliffe
authors.affiliation: CardioNomics Research Group, Clinical Research and Imaging Centre (CRIC) Bristol, Bristol Heart Institute, University Hospitals Bristol NHS Foundation Trust, Upper Maudlin Street, Bristol BS2 8HW.
authors.forename: Amy E
authors.initials: AE
authors.lastname: Burchell
authors.affiliation: School of Physiology, Pharmacology and Neuroscience, Faculty of Biomedical Sciences, University of Bristol, Bristol, UK.|CardioNomics Research Group, Clinical Research and Imaging Centre (CRIC) Bristol, Bristol Heart Institute, University Hospitals Bristol NHS Foundation Trust, Upper Maudlin Street, Bristol BS2 8HW.
authors.forename: Emma C
authors.initials: EC
authors.lastname: Hart
authors.affiliation: NIHR Bristol Cardiovascular Biomedical Research Unit, Bristol Heart Institute, University Hospitals Bristol NHS Foundation Trust, Upper Maudlin Street, Bristol BS2 8HW, UK.|Department of Radiology, Bristol Royal Infirmary, University Hospitals Bristol NHS Foundation Trust, Bristol, UK.
authors.forename: Mark C K
authors.initials: MC
authors.lastname: Hamilton
authors.affiliation: NIHR Bristol Cardiovascular Biomedical Research Unit, Bristol Heart Institute, University Hospitals Bristol NHS Foundation Trust, Upper Maudlin Street, Bristol BS2 8HW, UK.|Department of Cardiology, Bristol Heart Institute, University Hospitals Bristol NHS Foundation Trust, Bristol, UK.|CardioNomics Research Group, Clinical Research and Imaging Centre (CRIC) Bristol, Bristol Heart Institute, University Hospitals Bristol NHS Foundation Trust, Upper Maudlin Street, Bristol BS2 8HW.
authors.forename: Angus K
authors.initials: AK
authors.lastname: Nightingale
authors.affiliation: School of Physiology, Pharmacology and Neuroscience, Faculty of Biomedical Sciences, University of Bristol, Bristol, UK.|CardioNomics Research Group, Clinical Research and Imaging Centre (CRIC) Bristol, Bristol Heart Institute, University Hospitals Bristol NHS Foundation Trust, Upper Maudlin Street, Bristol BS2 8HW.
authors.forename: Julian F R
authors.initials: JF
authors.lastname: Paton
authors.affiliation: NIHR Bristol Cardiovascular Biomedical Research Unit, Bristol Heart Institute, University Hospitals Bristol NHS Foundation Trust, Upper Maudlin Street, Bristol BS2 8HW, UK.|Department of Radiology, Bristol Royal Infirmary, University Hospitals Bristol NHS Foundation Trust, Bristol, UK.
authors.forename: Nathan E
authors.initials: NE
authors.lastname: Manghat
authors.affiliation: NIHR Bristol Cardiovascular Biomedical Research Unit, Bristol Heart Institute, University Hospitals Bristol NHS Foundation Trust, Upper Maudlin Street, Bristol BS2 8HW, UK.|Department of Cardiology, Bristol Heart Institute, University Hospitals Bristol NHS Foundation Trust, Bristol, UK.|School of Clinical Sciences, Faculty of Health Sciences, University of Bristol, Bristol, UK.
authors.forename: Chiara
authors.initials: C
authors.lastname: Bucciarelli-Ducci
mesh_terms: D000328:Adult; D016022:Case-Control Studies; D015897:Comorbidity; D003287:Contrast Media; D004562:Electrocardiography / Q000379:methods*; D005260:Female; D005355:Fibrosis / Q000000981:diagnostic imaging / Q000473:pathology; D005682:Gadolinium; D006801:Humans; D006973:Hypertension / Q000175:diagnosis / Q000453:epidemiology*; D017379:Hypertrophy, Left Ventricular / Q000000981:diagnostic imaging* / Q000453:epidemiology*; D019028:Magnetic Resonance Imaging, Cine / Q000379:methods*; D008297:Male; D008875:Middle Aged; D009206:Myocardium / Q000473:pathology; D011379:Prognosis; D012189:Retrospective Studies; D012720:Severity of Illness Index
chemical_list: D003287:Contrast Media; D005682:Gadolinium
keywords: ECG; fibrosis; hypertension; hypertrophy; myocardial strain; remodelling