title: Strain analysis during exercise in patients with left ventricular hypertrophy: impact of etiology.
abstract: BACKGROUND
  Hypertrophic cardiomyopathy (HCM) and aortic stenosis (AS) may influence left ventricular (LV) systolic function, despite preservation of LV ejection fraction. The aim of this study was to determine the relative importance of cardiac afterload and myocardial hypertrophy in the potential dysfunction of myocardial deformation, at rest and during standardized exercise.
  
  
  METHODS
  Patients with moderate to severe (≤ 1.5 cm(2)) asymptomatic AS and patients with HCM in sinus rhythm were prospectively studied using resting and exercise echocardiography during submaximal exercise. Myocardial deformations were assessed using two-dimensional strain. Exclusion criteria were altered LV ejection fraction (<50%), coronary artery disease, intra-LV obstruction > 30 mm Hg at rest, diastolic LV thickness ≥ 30 mm, and New York Heart Association class > II. Thus, 50 patients (25 with AS, 25 with HCM) were selected and matched for age, sex, rest and exercise blood pressure, degree of LV hypertrophy (defined by maximal wall thickness), and LV ejection fraction.
  
  
  RESULTS
  Mean resting global longitudinal strain (GLS) was -14.9 ± 4.7% in patients with AS and -16.1 ± 3.9% in those with HCM (P = .30). During exercise (mean heart rate, 110 ± 10 beats/min), mean GLS was -13.9 ± 4.2% in patients with AS and -18.1 ± 5.4% in those with HCM (P = .004). GLS decreased in patients with AS but increased in those with HCM (ΔGLS, 0.9 ± 3.1% and -1.9 ± 3.2%, respectively, P = .003). The same results were observed for global circumferential strain. Mean resting global circumferential strain was -16.4 ± 5.8% in patients with AS and -17.9 ± 4.5% in those with HCM (P = .36). During exercise, mean global circumferential strain was -13.8 ± 4.1% in patients with AS and -18.6 ± 5.3% in those with HCM (P = .011). Afterload was higher, particularly during exercise, in patients with AS than in those with HCM.
  
  
  CONCLUSIONS
  Longitudinal and circumferential LV deformation during exercise was lower in patients with AS compared with those with HCM, despite similar resting characteristics. The greater afterload observed in patients with AS led to reduced contractile reserve.
authors.affiliation: Department of Physiology, Université Rennes 1, Rennes, France; INSERM UMR 1099, Rennes, France; CIC-IT 804, Université Rennes 1, CHU Rennes, Rennes, France.
authors.forename: Frédéric
authors.initials: F
authors.lastname: Schnell
authors.affiliation: INSERM UMR 1099, Rennes, France; Department of Cardiology, Pontchaillou Hospital, Rennes, France; CIC-IT 804, Université Rennes 1, CHU Rennes, Rennes, France. Electronic address: erwan.donal@chu-rennes.fr.
authors.forename: Erwan
authors.initials: E
authors.lastname: Donal
authors.affiliation: INSERM UMR 1099, Rennes, France; CIC-IT 804, Université Rennes 1, CHU Rennes, Rennes, France.
authors.forename: Anne
authors.initials: A
authors.lastname: Bernard-Brunet
authors.affiliation: INSERM UMR 1099, Rennes, France; CIC-IT 804, Université Rennes 1, CHU Rennes, Rennes, France.
authors.forename: Amélie
authors.initials: A
authors.lastname: Reynaud
authors.affiliation: Department of Sports Medicine, ASPETAR, Qatar Orthopaedic and Sports Medicine Hospital, Doha, Qatar.
authors.forename: Mathew G
authors.initials: MG
authors.lastname: Wilson
authors.affiliation: Department of Cardiology, Pontchaillou Hospital, Rennes, France.
authors.forename: Christophe
authors.initials: C
authors.lastname: Thebault
authors.affiliation: Department of Cardiology, Pontchaillou Hospital, Rennes, France.
authors.forename: Carine
authors.initials: C
authors.lastname: Ridard
authors.affiliation: INSERM UMR 1099, Rennes, France; Department of Cardiology, Pontchaillou Hospital, Rennes, France; CIC-IT 804, Université Rennes 1, CHU Rennes, Rennes, France.
authors.forename: Philippe
authors.initials: P
authors.lastname: Mabo
authors.affiliation: Department of Physiology, Université Rennes 1, Rennes, France; INSERM UMR 1099, Rennes, France; CIC-IT 804, Université Rennes 1, CHU Rennes, Rennes, France.
authors.forename: François
authors.initials: F
authors.lastname: Carré
mesh_terms: D000293:Adolescent; D000328:Adult; D001024:Aortic Valve Stenosis / Q000000981:diagnostic imaging* / Q000503:physiopathology*; D015150:Echocardiography, Doppler / Q000379:methods; D015444:Exercise / Q000502:physiology*; D005260:Female; D006352:Heart Ventricles / Q000000981:diagnostic imaging*; D006801:Humans; D017379:Hypertrophy, Left Ventricular / Q000000981:diagnostic imaging* / Q000209:etiology / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D018487:Ventricular Dysfunction, Left / Q000000981:diagnostic imaging*; D055815:Young Adult
keywords: 2D; AS; Aortic stenosis; Exercise echocardiography; GCS; GLS; Global circumferential strain; Global longitudinal strain; HCM; Hypertrophic cardiomyopathy; LV; LVESMWS; LVESV; LVH; Left ventricular; Left ventricular end-systolic meridional wall stress; Left ventricular end-systolic volume; Left ventricular hypertrophy; Longitudinal function; Strain; Two-dimensional