title: Systolic and diastolic myocardial mechanics in hypertrophic cardiomyopathy and their link to the extent of hypertrophy, replacement fibrosis and interstitial fibrosis.
abstract: Aim of the present study was to investigate the relations between myocardial mechanics and the extent of hypertrophy and fibrosis in hypertrophic cardiomyopathy (HCM). Forty-five consecutive patients with HCM and 15 subjects without structural heart disease were included. Cardiac magnetic resonance with late gadolinium enhancement (LGE) imaging was performed to evaluate biventricular function, LV mass index and presence/extent of LGE, expression of replacement fibrosis. Myocardial T1 relaxation, a surrogate of interstitial fibrosis, was measured from Look-Locker sequence. Feature-tracking analysis was applied to LV basal, mid and apical short-axis images to assess systolic and diastolic global LV circumferential strain (CS) and strain rate (CSr). Peak systolic CS and CSr were significantly higher among HCM patients as compared to control subjects (p = 0.015 and p = 0.007, respectively). The ratio of peak CSr during early filling to peak systolic CSr was significantly lower among HCM patients (p = 0.002). At multivariate linear regression analysis, LV mass index (p < 0.001) and %LV LGE (p = 0.011) were significantly and independently related to peak systolic CS; LV mass index (p < 0.001) and %LV LGE (p = 0.023) were significantly and independently related to peak systolic CSr; %LV LGE (p = 0.021) and T1 ratio (p = 0.006) were significantly and independently related to the ratio of peak CSr during early filling to peak systolic CSr. LV systolic mechanics are enhanced and LV diastolic mechanics are impaired in HCM. Extent of hypertrophy and replacement fibrosis influence the LV systolic mechanics while extent of replacement fibrosis and interstitial fibrosis influence the LV diastolic mechanics.
authors.affiliation: Division of Cardiology, Cardiothoracic Department, University Hospital "Santa Maria della Misericordia", Udine, Italy. gnucifora@outlook.com.
authors.forename: Gaetano
authors.initials: G
authors.lastname: Nucifora
authors.affiliation: Division of Cardiology, Cardiothoracic Department, University Hospital "Santa Maria della Misericordia", Udine, Italy.
authors.forename: Daniele
authors.initials: D
authors.lastname: Muser
authors.affiliation: Division of Cardiology, Cardiothoracic Department, University Hospital "Santa Maria della Misericordia", Udine, Italy.
authors.forename: Pasquale
authors.initials: P
authors.lastname: Gianfagna
authors.affiliation: Division of Cardiology, Cardiothoracic Department, University Hospital "Santa Maria della Misericordia", Udine, Italy.
authors.forename: Giorgio
authors.initials: G
authors.lastname: Morocutti
authors.affiliation: Division of Cardiology, Cardiothoracic Department, University Hospital "Santa Maria della Misericordia", Udine, Italy.
authors.forename: Alessandro
authors.initials: A
authors.lastname: Proclemer
mesh_terms: D000328:Adult; D000368:Aged; D001696:Biomechanical Phenomena; D002312:Cardiomyopathy, Hypertrophic / Q000150:complications* / Q000473:pathology / Q000503:physiopathology; D016022:Case-Control Studies; D016009:Chi-Square Distribution; D003287:Contrast Media / Q000008:administration & dosage; D003971:Diastole; D005260:Female; D005355:Fibrosis; D019786:Gadolinium DTPA / Q000008:administration & dosage; D006801:Humans; D017379:Hypertrophy, Left Ventricular / Q000209:etiology* / Q000473:pathology / Q000503:physiopathology; D016014:Linear Models; D019028:Magnetic Resonance Imaging, Cine; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D009206:Myocardium / Q000473:pathology*; D011237:Predictive Value of Tests; D012307:Risk Factors; D013318:Stroke Volume; D013599:Systole; D018487:Ventricular Dysfunction, Left / Q000209:etiology* / Q000473:pathology / Q000503:physiopathology; D016277:Ventricular Function, Left
chemical_list: D003287:Contrast Media; C064925:gadodiamide; D019786:Gadolinium DTPA
keywords: Cardiac magnetic resonance; Feature-tracking; Hypertrophic cardiomyopathy; Late gadolinium enhancement; Strain; T1 measurement