Clinical Value Analysis of Echocardiographic Evaluation of Left Atrial Structure and Function in Apical Hypertrophic Cardiomyopathy
Objective: To comprehensively assess the structural and functional changes of the left atrium in patients with apical hypertrophic cardiomyopathy (AHCM) using real-time three-dimensional echocardiography (RT-3DE) combined with two-dimensional speckle tracking imaging (2D-STI), and to explore the correlations between these changes and clinical indicators. By comparing the differences between AHCM patients and healthy controls, this study aims to provide new evidence for the clinical diagnosis, treatment, and prognosis assessment of AHCM. Methods: This study enrolled 150 AHCM patients treated at XX Hospital from January 2022 to January 2024 as the study group, and 150 healthy individuals who underwent physical examinations at the same hospital during the same period as the control group. The Philips EPIQ 7C premium color Doppler ultrasound diagnostic system, equipped with S5-1 and X5-1 two-dimensional and three-dimensional transthoracic ultrasound probes, was used to perform ultrasound examinations on the study subjects. RT-3DE technology was employed to measure left atrial volume parameters, including maximum left atrial volume (LAVmax) and minimum left atrial volume (LAVmin). Meanwhile, 2D-STI technology was utilized to assess left atrial myocardial strain rate parameters, such as left atrial reservoir strain (LASr) and left atrial conduit strain (LAScd). Additionally, general information, including age, gender, body surface area (BSA), blood pressure, and body mass index (BMI), was collected, and laboratory tests for blood routine and biochemical indicators were conducted. Statistical analysis was performed using SPSS 23.0 software to compare differences between the two groups and explore correlations. Results: Patients in the AHCM group had significantly higher age (P < 0.001) and heart rate (HR) (P < 0.001) compared to the control group. In terms of left atrial structure, the left atrial diameter (LAD), left atrial length (LAL), left atrial thickness (LAT), LAVmax, LAVmin, and left atrial volume index (LAVI) were significantly greater in the AHCM group than in the control group (all P < 0.05). Regarding left atrial function, the left atrial ejection fraction (LAEF), left atrial passive emptying fraction (LAPEF), and left atrial active emptying fraction (LAAEF) were significantly lower in the AHCM group than in the control group (all P < 0.05), while the left atrial systolic volume (LASV) was significantly increased (P < 0.001). Furthermore, the LASr and LAScd were significantly higher in the AHCM group than in the control group (P < 0.05), and the absolute values of peak left atrial reservoir strain rate (pLASRr) and peak left atrial contraction strain rate (pLASRcd) were also significantly higher in the AHCM group (P < 0.05). Correlation analysis revealed positive correlations between LAEF and pLASRc, pLASRcd (both P < 0.001), between LAAEF and pLASRr, pLASRcd (both P < 0.001), and between LAPEF and pLASRc, pLASRr (both P < 0.001). Subgroup analysis showed that left atrial functional parameters were significantly lower in NYHA III~IV patients compared to NYHA I~II patients (all P < 0.05), with significant differences in myocardial strain rate parameters (P < 0.05). Reproducibility test results indicated good repeatability for the measurements of LAEF and pLASRc (both P > 0.05). Conclusion: Significant changes have occurred in the structure and function of the left atrium in AHCM patients, manifested as increased left atrial volume, morphological abnormalities, and functional impairment. Meanwhile, there is a significant correlation between myocardial strain rate parameters and left atrial functional indicators, suggesting that myocardial strain rate parameters can be used to assess left atrial function in AHCM patients. These findings not only enrich our understanding of the pathophysiological mechanisms of AHCM but also provide new perspectives and evidence for clinical diagnosis and treatment. Future studies can further explore the mechanisms underlying the structural and functional changes of the left atrium in AHCM patients and their relationship with clinical prognosis, providing a scientific basis for developing more precise treatment plans.
Apical Hypertrophic Cardiomyopathy
心尖肥厚型心肌病(Apical Hypertrophic Cardiomyopathy, AHCM)作为一种特殊的肥厚型心肌病(Hypertrophic Cardiomyopathy, HCM)类型,自1976年由日本学者Yamaguchi等首次报告以来,逐渐受到临床医生的广泛关注
RT-3DE能够直接显示心腔的立体形态,无需对心室腔进行几何学假设,因此在测量心腔容积及评估心脏功能方面具有更高的准确性和可靠性
目前,关于RT-3DE联合2D-STI技术在评估AHCM患者左心房结构与功能方面的研究尚不多见。本研究旨在通过RT-3DE联合2D-STI技术,对AHCM患者的左心房容积、形态及心肌应变进行定量分析,探讨其在评估AHCM患者左心房结构与功能方面的价值。同时,本研究还将分析AHCM患者左心房结构与功能的变化与临床指标的相关性,以期为AHCM的临床诊断、治疗及预后评估提供新的参考依据,进而为临床治疗提供更为个性化的方案选择依据,从而改善患者预后。
实验组纳入标准:根据中华医学会超声医学分会超声心动图学组制定的指南
实验组排除标准:① 非AHCM的心肌病患者,如梗阻性肥厚型心肌病、限制型心肌病等;② 存在冠心病、心肌梗死、严重瓣膜病、心力衰竭等严重心血管疾病的患者;③ 实时三维超声心动图或二维斑点追踪技术的图像质量不佳,无法满足评估要求的患者;④ 缺失心电图,超声图像和实验室检查等临床资料。
使用飞利浦EPIQ 7C高端彩色多普勒超声诊断系统,S5-1及X5-1心脏探头,Qlab图像后处理软件包。
收集研究对象的一般资料,包括年龄、性别、身高、体重、体表面积(BSA)、血压体重指数(BMI),
心率。实验室指标的测定:血常规指标包括白细胞计数、红细胞计数、血小板计数和血红蛋白含量。生化指标:低密度脂蛋白、肌酐、葡萄糖和肌钙蛋白。心率以心电图报告值为准。所有入组患者体位采用左侧卧位,于静息状态下连接心电图设备后进行超声检查,常规采集并存储了左室的长轴切面、短轴切面、心尖四腔心、两腔心以及三腔心切面图像,并采集4个心动周期的动态图像用于后处理。
通过二维超声测量左房前后径(Left Atrial Diameter, LAD)、左房长径(Left Atrial Length, LAL)以及左房横径(Left Atrial Transverse, LAT),利用频谱多普勒技术细致测量并记录二尖瓣舒张早期的血流峰值速度E与舒张晚期的血流峰值速度A,并进一步计算出E/A比值(
在RT-3DE HM模式下进行心尖四腔心切面的分析,借助系统软件能够自动获取左心室射血分数LVEFHM和左心房容积(Maximum Left Atrial Volume) LAVmax这两个关键参数。进入a2DQ软件处理模式,给出LA双平面左房最大容积(LAVmax)、左房最小容积(LAVmin)等关键参数,进一步计算出左房射血分数LAEF和左房容积指数LAVI (
AHCM组与对照组相比,年龄方面,对照组平均年龄为46.47 ± 13.54岁,而AHCM组平均年龄显著增高至60.77 ± 9.71岁。两组间年龄差异具有高度统计学意义(t = 10.337, P < 0.001)。心率(HR)在两组间存在显著差异,对照组平均HR为74.07 ± 9.06次/分,而AHCM组则显著升高至104.53 ± 9.43次/分,t检验结果显示,两组间HR差异具有高度统计学意义(t = 105.649, P < 0.001)。性别构成比、身高、体重、体表面积(BSA)及身体质量指数(BMI)、血压在两组间无显著差异(χ2 = 0.623, P = 0.733)。结果如
在常规血液指标方面,两组间均未发现显著差异(P > 0.05)。在生化指标方面,低密度脂蛋白、肌酐及葡萄糖的均值在两组间也未发现显著差异(P > 0.05)。然而,值得注意的是,超敏肌钙蛋白水平在两组间存在显著差异,对照组的超敏肌钙蛋白均值为35.32 ± 5.17 ng/L,而AHCM组则显著升高至65.87 ± 5.25 ng/L,差异具有高度统计学意义(t = 7.297, P < 0.001)。结果如
AHCM组(n = 150) |
对照组(n = 150) |
t |
P |
|
t/χ2 |
||||
性别(男/女) |
85/65 |
87/63 |
0.623 |
0.733 |
年龄(year) |
60.77 ± 9.71 |
46.47 ± 13.54 |
10.337 |
<0.001 |
身高(cm) |
167.4 ± 7.51 |
167.27 ± 6.35 |
0.006 |
0.994 |
体重(kg) |
67.2 ± 8.65 |
64.23 ± 9.06 |
0.911 |
0.406 |
BSA (m²) |
1.73 ± 0.15 |
1.72 ± 0.15 |
0.067 |
0.935 |
BMI (Kg/m²) |
23.92 ± 1.99 |
22.86 ± 2.22 |
2.166 |
0.121 |
SBP (mmHg) |
120.17 ± 7.13 |
121.8 ± 8.42 |
1.344 |
0.266 |
DBP (mmHg) |
75.17 ± 5.98 |
75.13 ± 6.67 |
0.007 |
0.993 |
HR (次/min) |
104.53 ± 9.43 |
74.07 ± 9.06 |
105.649 |
<0.001 |
AHCM组(n = 150) |
对照组(n = 150) |
t |
P |
|
白细胞(×109/L) |
7.15 ± 4.32 |
7.05 ± 3.13 |
0.764 |
0.434 |
红细胞(×1012/L) |
4.45 ± 0.98 |
4.40 ± 1.09 |
0.422 |
0.758 |
血小板(×109/L) |
209.34 ± 70.32 |
212.18 ± 52.10 |
0.459 |
0.566 |
血红蛋白(g/L) |
137.23 ± 17.54 |
138.87 ± 21.34 |
0.367 |
0.734 |
低密度脂蛋白(mg/dL) |
2.55 ± 0.80 |
2.56 ± 0.76 |
0.357 |
0.756 |
肌酐(μmoI/L) |
77.18 ± 18.23 |
73.43 ± 22.33 |
0.869 |
0.267 |
葡萄糖(mg/dL) |
5.78 ± 1.50 |
5.67 ± 1.36 |
0.491 |
0.56 |
超敏肌钙蛋白(ng/L) |
65.87 ± 5.25 |
35.32 ± 5.17 |
7.297 |
<0.001 |
通过独立样本t检验分析发现两组之间在左心房直径(LAD)、左心房长度(LAL)以及左心房厚度(LAT)上存在显著差异(P均<0.001)。结果如
在AHCM组中,E峰流速显著降低,A峰流速显著增高,E/A比值显著降低。然而组织多普勒成像参数E'-sep和E'-lat,两组之间无显著差异(P值分别为0.325和0.952)。最后,E/E'比值在AHCM组中显著增高。结果如
AHCM组(n = 150) |
对照组(n = 150) |
t |
P |
|
LAD (mm) |
42.47 ± 2.60 |
34.10 ± 3.46 |
34.161 |
<0.001 |
LAL (mm) |
50.50 ± 2.23 |
45.46 ± 2.41 |
48.343 |
<0.001 |
LAT (mm) |
43.06 ± 2.27 |
37.01 ± 3.45 |
39.011 |
<0.001 |
AHCM组(n = 150) |
对照组(n = 150) |
t |
P |
|
E-mv (m/s) |
0.72 ± 0.16 |
0.83 ± 0.14 |
2.862 |
0.006 |
A-mv (m/s) |
0.82 ± 0.2 |
0.61 ± 0.12 |
-4.806 |
<0.001 |
E/A |
0.94 ± 0.39 |
1.44 ± 0.50 |
4.376 |
<0.001 |
E'-sep (cm/s) |
9.62 ± 1.42 |
10.04 ± 1.88 |
0.992 |
0.325 |
E'-lat (cm/s) |
12.34 ± 1.11 |
12.37 ± 2.13 |
0.061 |
0.952 |
E/E' |
7.14 ± 1.56 |
6.32 ± 1.56 |
-2.032 |
0.047 |
AHCM组的左心房结构参数显著异于对照组,具体表现为最大左心房容积(LAVmax)、最小左心房容积(LAVmin)、左心房前负荷容积(LAVpre)以及左心房容积指数(LAVI)均显著增加,差异均具有统计学意义,结果如
AHCM组(n = 150) |
对照组(n = 150) |
t |
P |
|
LAVmax (mL) |
61.62 ± 1.53 |
39.24 ± 1.4 |
4.08 |
0.02 |
LAVmin (mL) |
31.37 ± 0.67 |
16.31 ± 0.76 |
20.095 |
<0.001 |
LAVpre (mL) |
17.97 ± 3.14 |
12.63 ± 2.98 |
3.965 |
<0.001 |
LAVI |
35.84 ± 0.74 |
22.84 ± 0.79 |
82.075 |
<0.001 |
AHCM组的左心室射血分数(LVEF HM)显著低于对照组,同时左心房收缩容积(LASV)显著增加。此外,AHCM组的左心房排空分数(LAEF)、左心房被动排空分数(LAPEF)及左心房主动排空分数(LAAEF)均较对照组显著降低,这些差异均具有统计学意义。结果如
AHCM组(n = 150) |
对照组(n = 150) |
t |
P |
|
LVEF HM (%) |
62.03 ± 0.42 |
65.83 ± 0.56 |
40.2 |
<0.001 |
LASV |
42.94 ± 4.87 |
36.78 ± 4.77 |
25.977 |
<0.001 |
LAEF (%) |
47.40 ± 0.87 |
60.54 ± 0.86 |
4.188 |
0.018 |
LAPEF (%) |
46.28 ± 6.32 |
57.75 ± 5.09 |
6.977 |
<0.001 |
LAAEF (%) |
34.65 ± 6.29 |
46.83 ± 4.87 |
7.053 |
<0.001 |
AHCM组的左心房储存率(LASr)和左心房收缩期应变率(LAScd)显著高于对照组,同时左心房峰值储备应变率(pLASRr)和左心房收缩期峰值应变率(pLASRcd)的绝对值也显著高于对照组,而左心房整体纵向应变(LASct)和左心房峰值储备应变率(pLASRct)在两组间无显著差异(P > 0.05)。结果如
AHCM组(n = 150) |
对照组(n = 150) |
t |
P |
|
LASct (%) |
16.27 ± 3.50 |
16.06 ± 2.39 |
−0.269 |
0.789 |
LASr (%) |
37.50 ± 5.63 |
33.69 ± 4.17 |
−3.043 |
0.003 |
LAScd (%) |
21.23 ± 2.94 |
17.63 ± 3.19 |
−4.619 |
<0.001 |
pLASRct (s−1) |
−2.85 ± 0.99 |
−2.88 ± 1.13 |
−0.092 |
0.927 |
pLASRr (s−1) |
2.59 ± 1.18 |
2.03 ± 0.80 |
−2.18 |
0.033 |
pLASRcd (s−1) |
−2.41 ± 0.89 |
−1.83 ± 0.91 |
2.52 |
0.014 |
pLASRc |
pLASRr |
pLASRcd |
||
LAEF |
r |
0.477 |
0.36 |
0.633 |
p |
<0.001 |
<0.001 |
<0.001 |
|
LAAEF |
r |
0.231 |
0.532 |
0.532 |
p |
0.021 |
<0.001 |
<0.001 |
|
LAPEF |
r |
0.583 |
0.509 |
0.278 |
p |
<0.001 |
<0.001 |
0.033 |
NYHA I~II (n = 94) |
NYHA III~IV (n = 56) |
t |
P |
|
LAEF |
49.39 ± 5.77 |
43.48 ± 4.42 |
5.677 |
<0.001 |
LAAEF |
51.54 ± 6.08 |
41.86 ± 5.48 |
8.976 |
<0.001 |
LAPEF |
37.09 ± 4.33 |
30.65 ± 3.97 |
6.809 |
<0.001 |
pLASRct |
−2.86 ± 0.32 |
−2.77 ± 0.28 |
5.43 |
<0.001 |
pLASRr |
2.35 ± 0.25 |
3.80 ± 0.37 |
6.843 |
<0.001 |
pLASRcd |
−2.17 ± 0.19 |
−2.89 ± 0.22 |
3.081 |
0.032 |
变量 |
平均差值(95%CI) |
t |
P |
LAEF |
|||
组内 |
2.16 (−2.65, 6.90) |
0.94 |
0.359 |
组间 |
0.92 (−4.13, 5.97) |
0.378 |
0.717 |
pLASRct |
|||
组内 |
0.15 (−8.97, 9.67) |
0.043 |
0.966 |
组间 |
1.39 (−7.43, 10.53) |
0.339 |
0.745 |
AHCM作为一种特殊类型的心肌肥厚疾病,其临床特征主要表现为心室肌肥厚局限于心尖部,常伴随有胸闷、胸痛、心悸及呼吸困难等症状,严重影响患者的生活质量及预后
基本信息比较结果显示,在年龄方面,AHCM组的平均年龄显著高于对照组,这一发现与先前的研究一致,表明AHCM更倾向于在中老年人群中发病,这种年龄差异可能反映了随着年龄增长,心脏结构和功能逐渐发生变化,增加了AHCM的发病风险
AHCM组的左心房结构参数显著异于对照组,具体表现为LAVmax、LAVmin、LAVpre以及LAVI均显著增加,这些发现对于深入理解AHCM患者左心房重构的病理生理机制及其临床意义具有重要意义。LAVI的增大不仅与心脏疾病的严重程度相关,还是预测心血管事件风险的重要指标
AHCM组的左心房功能研究结果显示,AHCM患者的LVEF HM显著低于对照组,同时LASV显著增加,LAEF、LAPEF及LAAEF均较对照组显著降低。这些发现不仅揭示了AHCM患者左心室及左心房功能的显著受损,LAPEF和LAAEF的降低可能进一步加剧左心房的充盈负荷和重构进程,形成恶性循环
本研究结果显示AHCM组的LASr和LAScd显著高于对照组,pLASRr和pLASRcd的绝对值亦显著高于对照组,这一发现与之前的研究结果相一致,提示AHCM患者的左心房功能可能发生了适应性改变,以应对左心室舒张功能障碍。
本研究进一步分析了不同NYHA分级患者之间左心房功能及心肌应变率参数的差异。结果显示,NYHA III~IV级患者的LAEF、LAAEF和LAPEF均显著低于NYHA I~II级患者。这可能是由于心肌应变率是反映心肌纤维主动缩短或延长的速度,而左心房功能的储器期、管道期和收缩泵功能均依赖心肌的主动形变能力 。如左房在心室收缩期被动储存血液,此时应变率(如LASr)反映心房壁的弹性扩张能力,与心肌纤维的延展性相关;而左房主动收缩将血液泵入左室,收缩期应变率(LASct)直接反映心房肌的主动收缩力。这一研究结果也印证了这一机制,当AHCM病情的加重时,患者左心房的整体射血功能、主动射血功能以及被动射血功能均受到显著影响
实时三维超声心动图联合二维斑点追踪技术在评估AHCM患者左心房结构与功能方面展现出了显著的技术优势,使得对AHCM患者左心房结构与功能的评估更加全面和准确。在临床应用方面,该技术具有无创、实时、可重复等优点,能够为医生提供关于AHCM患者左心房结构与功能的客观依据