目的:本研究的目的是评估心脏淀粉样变性(CA)患者的心脏MRI结构参数和应变成分的诊断性能和关系,并评估这些变量区分CA和非淀粉样蛋白心肌肥大(NACH)的能力。
方法:70例CA患者(56例男性;平均年龄,76±10[标准差]年)和32名患者(19名男性;平均年龄,63±10[标准偏差]年)的NACH进行了心脏MRI检查。特征跟踪(FT)全局纵向应变(GLS),径向应变(GRS),周向应变(GCS),应变AB比(根尖应变除以基础应变),计算心肌T1、心肌T2和细胞外容积(ECV)。使用Mann-Whitney秩和检验对CA患者和NACH患者进行比较。使用接受者工作特征曲线下面积(AUC)估计每个变量区分CA和NACH的能力。
结果:CA患者的GLS中位数较高(-7.0%[Q1,-9.0;Q3,-5.0]),GCS中位数较高(-12.0%[第一季度,-15.0;第三季度,-9.0]),GRS中位数(16.5%[Q1,13.0;Q3,23.0])低于NACH(-9.0%[Q1,-11.0;Q3,-8.0];-17.0%[Q1,-20.0;Q3,-14.0];和25.5%[Q1,16.0;Q3,31.5],分别)(全部P<0.001)。CA患者的心肌T1和ECV中位数显着升高(1112ms[Q1,1074;Q3,1146]和47%[Q1,41;Q3,55],分别)比具有NACH(1056ms[Q1,1011;Q3,1071]和28%[Q1,26;Q3,30],分别)(P<0.001)。基础ECV对CA的诊断表现最佳(AUC=0.975;95%置信区间[CI]:0.947-1)。对于CA的诊断,GRS的AB比率(0.843;95%CI:0.768-0.918)和基础心肌T1(0.834;95%CI:0.741-0.928)之间的AUC没有差异(P=0.81)。FT-GRS的AB比率和基础心肌T1的组合具有与基础ECV的诊断性能没有差异(P=0.06)。
结论:ECV在心脏MRI诊断CA方面优于FT应变。与心肌T1相关的FT-GRS的AB比提供了与ECV相似的诊断性能。
OBJECTIVE: The purpose of this study was to evaluate the diagnostic performance and relationships of cardiac MRI structural parameters and strain components in patients with cardiac amyloidosis (CA) and to estimate the capabilities of these variables to discriminate between CA and non-amyloid cardiac hypertrophy (NACH).
METHODS: Seventy patients with CA (56 men; mean age, 76 ± 10 [standard deviation] years) and 32 patients (19 men; mean age, 63 ± 10 [standard deviation] years) with NACH underwent cardiac MRI. Feature tracking (FT) global longitudinal strain (GLS), radial strain (GRS), circumferential strain (GCS), strain AB ratio (apical strain divided by basal strain), myocardial T1, myocardial T2 and extracellular volume (ECV) were calculated. Comparisons between patients with CA and those with NACH were made using Mann-Whitney rank sum test. The ability of each variable to discriminate between CA and NACH was estimated using area under the receiver operating characteristic curve (AUC).
RESULTS: Patients with CA had higher median GLS (-7.0% [Q1, -9.0; Q3, -5.0]), higher median GCS (-12.0% [Q1, -15.0; Q3, -9.0]), and lower median GRS (16.5% [Q1, 13.0; Q3, 23.0]) than those with NACH (-9.0% [Q1, -11.0; Q3, -8.0]; -17.0% [Q1, -20.0; Q3, -14.0]; and 25.5% [Q1, 16.0; Q3, 31.5], respectively) (P < 0.001 for all). Median myocardial T1 and ECV were significantly higher in patients with CA (1112 ms [Q1, 1074; Q3, 1146] and 47% [Q1, 41; Q3, 55], respectively) than in those with NACH (1056 ms [Q1, 1011; Q3, 1071] and 28% [Q1, 26; Q3, 30], respectively) (P < 0.001). Basal ECV showed the best performance for the diagnosis of CA (AUC = 0.975; 95% confidence interval [CI]: 0.947-1). No differences in AUC were found between AB ratio of GRS (0.843; 95% CI: 0.768-0.918) and basal myocardial T1 (0.834; 95% CI: 0.741-0.928) for the diagnosis of CA (P = 0.81). The combination of the AB ratio of FT-GRS and basal myocardial T1 had a diagnostic performance not different from that of basal ECV (P = 0.06).
CONCLUSIONS: ECV outperforms FT-strain for the diagnosis of CA with cardiac MRI. The AB ratio of FT-GRS associated with myocardial T1 provides diagnostic performance similar to that achieved by ECV.