Mazurkiewicz Łukasz, Ziółkowska Lidia, Petryka Joanna, Śpiewak Mateusz, Małek Łukasz, Kubik Agata, Marczak Magdalena, Misko Jolanta, Brzezińska-Rajszys Grażyna
Department of Cardiomyopathies, CMR Unit, Institute of Cardiology, Warsaw, Poland.
Department of Pediatric Cardiology, The Children's Memorial Health Institute, Warsaw, Poland.
Magn Reson Imaging. 2017 Nov;43:56-65. doi: 10.1016/j.mri.2017.07.003. Epub 2017 Jul 5.
To assess the magnitude of myocardial displacement abnormalities and their alterations with the fibrosis, left-ventricular (LV) outflow tract obstruction (LVOTO) and hypertrophy in juveniles with hypertrophic cardiomyopathy (HCM).
Fifty-five children [age 12,5±4.6years, 38 (69,1%) males, 19 (34,5%) with LVOTO] with HCM and 20 controls underwent cardiovascular magnetic resonance. The LV feature tracking (FT) derived strain and strain rates were quantified. Results of FT analysis were compared between HCM subjects and controls and between children with and without LVOTO.
Children with HCM exhibited decreased strain in both hypertrophied and nonhypertrophied segments versus controls. LV global longitudinal strain (LVGLS) rate (-0.69±0.04 vs -0.91±0.05, p=0,04), LV circumferential strain (LVCR) rate (-0.98±0.09 vs -1.27±0.06, p=0,02), LV radial strain (LVR) (18,5±1.9 vs 27,4±1.4, p<0,01) and LVR rate (0,98±0.1 vs 1,53±0.08, p<0,01) were substantially compromised in subjects with LVOTO vs without. In multivariable regression all LV myocardial dynamics markers, except for LVCR, exhibited a significant association with the degree of LVOTO. LVCR rate (β=0,31, p=0,02) and LVR (β=-0.24, p=0,04) were related to LV mass and only LVCR rate (β=0,15, p=0,03) was associated with the amount of LV fibrosis.
The reduction of all indices of LV myocardial mechanics in juvenile HCM patients was global but particularly pronounced in hypertrophied segments of the LV. The majority of the LV strains and strain rates were substantially compromised in subjects with LVOTO compared to patients without the obstruction. Myocardial mechanics indices seemed to be related to the degree of LVOTO rather than either to mass or the amount of fibrosis.
评估肥厚型心肌病（HCM）青少年患者心肌位移异常的程度及其随纤维化、左心室（LV）流出道梗阻（LVOTO）和肥厚的变化情况。
55例HCM患儿[年龄12.5±4.6岁，38例（69.1%）为男性，19例（34.5%）有LVOTO]和20例对照者接受了心血管磁共振检查。对左心室特征追踪（FT）得出的应变和应变率进行了量化。比较了HCM受试者与对照者之间以及有和无LVOTO的儿童之间FT分析的结果。
与对照者相比，HCM患儿肥厚节段和非肥厚节段的应变均降低。LV整体纵向应变（LVGLS）率（-0.69±0.04对-0.91±0.05，p=0.04）、LV圆周应变（LVCR）率（-0.98±0.09对-1.27±0.06，p=0.02）、LV径向应变（LVR）（18.5±1.9对27.4±1.4，p<0.01）和LVR率（0.98±0.1对1.53±0.08，p<0.01）在有LVOTO的受试者中与无LVOTO的受试者相比明显受损。在多变量回归中，除LVCR外，所有LV心肌动力学指标均与LVOTO程度呈显著相关。LVCR率（β=0.31，p=0.02）和LVR（β=-0.24，p=0.04）与LV质量相关，且只有LVCR率（β=0.15，p=0.03）与LV纤维化程度相关。
青少年HCM患者LV心肌力学所有指标的降低是全身性的，但在LV肥厚节段尤为明显。与无梗阻患者相比，有LVOTO的受试者中大多数LV应变和应变率明显受损。心肌力学指标似乎与LVOTO程度相关，而非与质量或纤维化程度相关。
