Truong Vien T, Li Candice Y, Brown Rebeccah L, Moore Ryan A, Garcia Victor F, Crotty Eric J, Taylor Michael D, Ngo Tam M N, Mazur Wojciech
Department of Cardiology, The Christ Hospital; Cincinnati, Ohio, United States of America.
Department of Cardiology, Pham Ngoc Thach University of Medicine, Ho Chi Minh City, Viet Nam.
PLoS One. 2017 Dec 11;12(12):e0189128. doi: 10.1371/journal.pone.0189128. eCollection 2017.
To investigate the right ventricular (RV) strain in pectus excavatum (PE) patients using cardiac magnetic resonance tissue tracking (CMR TT).
Fifty consecutive pectus excavatum patients, 10 to 32 years of age (mean age 15 ± 4 years), underwent routine cardiac magnetic resonance imaging (CMR) including standard measures of chest geometry and cardiac size and function. The control group consisted of 20 healthy patients with a mean age of 17 ± 5 years. RV longitudinal and circumferential strain magnitude was assessed by a dedicated RV tissue tracking software.
Fifty patients with images of sufficient quality were included in the analysis. The mean right and left ventricular ejection fractions were 55 ± 5% and 59 ± 4%. The RV global longitudinal strain was -21.88 ± 4.63%. The RV circumferential strain at base, mid-cavity and apex were -13.66 ± 3.09%, -11.31 ± 2.79%, -20.73 ± 3.45%, respectively. There was no statistically significant decrease in right ventricular or left ventricular ejection fraction between patients and controls (p > 0.05 for each). There was no significant difference in RV global longitudinal strain between two groups (-21.88 ± 4.63 versus -21.99 ± 3.58; p = 0.93). However, there was significant decrease in mid-cavity circumferential strain magnitude in pectus patients compared with controls (-11.31 ± 2.79 versus -16.19 ± 2.86; p < 0.001). PE patients had a significantly higher basal circumferential strain (-13.66 ± 3.09% versus -9.76 ± 1.79; p < 0.001) as well as apical circumferential strain (-20.73 ± 3.45% versus -12.07 ± 3.38) than control group.
Mid-cavity circumferential strain but not longitudinal strain is reduced in pectus excavatum patients. Basal circumferential strain as well as apical circumferential strain were increased as compensatory mechanism for reduced mid-cavity circumferential strain. Further studies are needed to establish clinical significance of this finding.
使用心脏磁共振组织追踪技术（CMR TT）研究漏斗胸（PE）患者的右心室（RV）应变。
连续纳入50例年龄在10至32岁（平均年龄15±4岁）的漏斗胸患者，进行常规心脏磁共振成像（CMR），包括胸部几何形状、心脏大小和功能的标准测量。对照组由20名平均年龄为17±5岁的健康患者组成。通过专用的右心室组织追踪软件评估右心室纵向和圆周应变幅度。
分析纳入了50例图像质量足够的患者。右心室和左心室平均射血分数分别为55±5%和59±4%。右心室整体纵向应变为-21.88±4.63%。右心室基部、中腔和心尖处的圆周应变分别为-13.66±3.09%、-11.31±2.79%、-20.73±3.45%。患者与对照组之间右心室或左心室射血分数无统计学显著下降（每组p>0.05）。两组之间右心室整体纵向应变无显著差异（-21.88±4.63对-21.99±3.58；p=0.93）。然而，与对照组相比，漏斗胸患者中腔圆周应变幅度显著降低（-11.31±2.79对-16.19±2.86；p<0.001）。漏斗胸患者的基部圆周应变（-13.66±3.09%对-9.76±1.79；p<0.001）以及心尖圆周应变（-20.73±3.45%对-12.07±3.38）均显著高于对照组。
漏斗胸患者中腔圆周应变降低，但纵向应变未降低。基部圆周应变以及心尖圆周应变增加，作为中腔圆周应变降低的代偿机制。需要进一步研究以确定这一发现的临床意义。
