Xiao Minghu, Wang Jingjin, Nie Changrong, Zhu Changsheng, Sun Xin, Meng Yanhai, Zhu Zhenhui, Wang Hao, Wang Shuiyun
State Key Laboratory of Cardiovascular Disease, Department of Echocardiography, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China.
State Key Laboratory of Cardiovascular Disease, Department of Cardiovascular Surgery, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China.
J Am Soc Echocardiogr. 2025 Aug;38(8):698-709. doi: 10.1016/j.echo.2025.04.018. Epub 2025 May 6.
Left ventricular midventricular obstruction (MVO) is thought to be dynamic with hypertrophic cardiomyopathy (HCM). Therefore, the distance between the anterior papillary muscle (APM) and the interventricular septum (IVS) was used to assess MVO on rest echocardiography.
MVO was defined as a midventricular gradient of ≥30 mm Hg at rest or after being provoked. APM-IVS distance was analyzed in the apical three-chamber view at end-diastole.
A total of 2,125 patients with HCM were enrolled in this study. Among these, data from 1,453 patients with measurable APM-IVS distances were analyzed. Of the 1,453 patients, 596 had MVO, while 857 did not exhibit MVO. Multivariate logistic regression analyses showed that APM-IVS distance was an independent indicator of MVO (adjusted odds ratio, 0.487; 95% CI, 0.448-0.529). APM-IVS distance demonstrated the highest diagnostic accuracy in identifying MVO, exhibiting an area under the receiver operating characteristic curve of 0.949 (95% CI, 0.937-0.960). The presence of a smaller APM-IVS distance was correlated with increased incidence of left ventricular apical aneurysm and MVO, elevated levels of N-terminal pro-brain natriuretic peptide, and higher New York Heart Association functional class. Among patients with MVO, 198 underwent surgical myectomy and were followed up after a median time of 12 months. APM-IVS distance increased from 7.6 ± 2.2 to 18.9 ± 4.9 mm, and the peak midventricular gradient decreased from 50 mm Hg (36-57 mm Hg) to 3 mm Hg (3-7 mm Hg) at follow-up.
A small APM-IVS distance was associated with MVO, which was alleviated after myectomy following an increase in APM-IVS distance.
左心室室中梗阻（MVO）被认为在肥厚型心肌病（HCM）中呈动态变化。因此，在静息超声心动图检查中，使用前乳头肌（APM）与室间隔（IVS）之间的距离来评估MVO。
MVO定义为静息时或激发后室中梯度≥30 mmHg。在舒张末期的心尖三腔视图中分析APM-IVS距离。
本研究共纳入2125例HCM患者。其中，分析了1453例可测量APM-IVS距离患者的数据。在这1453例患者中，596例有MVO，而857例未表现出MVO。多因素逻辑回归分析显示，APM-IVS距离是MVO的独立指标（调整后的优势比为0.487；95%置信区间为0.448-0.529）。APM-IVS距离在识别MVO方面表现出最高的诊断准确性，其受试者操作特征曲线下面积为0.949（95%置信区间为0.937-0.960）。APM-IVS距离较小与左心室心尖部动脉瘤和MVO的发生率增加、N末端脑钠肽前体水平升高以及纽约心脏协会功能分级较高相关。在有MVO的患者中，198例行外科心肌切除术，并在中位时间12个月后进行随访。随访时，APM-IVS距离从7.6±2.2 mm增加到18.9±4.9 mm，室中峰值梯度从50 mmHg（36-57 mmHg）降至3 mmHg（3-7 mmHg）。
APM-IVS距离较小与MVO相关，心肌切除术后APM-IVS距离增加，MVO得到缓解。
