Fractional flow reserve measurement based on coronary angiographic images

描述(申请人提供)：冠状动脉造影术是确定冠状动脉解剖结构和评估动脉粥样硬化的标准方法。然而，使用目测估计来评估冠状动脉疾病和管腔狭窄的严重程度有一定的局限性。这些限制包括冠脉狭窄病变的主观视觉分级导致的观察者内和观察者间的巨大变异性。尤其是在中度冠状动脉病变(30%-70%直径狭窄)的情况下，冠状动脉造影术在区分引起缺血的中度冠状动脉病变和非引起缺血的冠状动脉病变方面非常有限。此外，病理结果表明，根据冠状动脉造影术估计的冠状动脉狭窄程度与死后心脏测量的狭窄病变的实际严重程度之间缺乏相关性。由于标准冠状动脉造影术的主要局限性，需要一种功能测量狭窄严重程度的方法，如测量心导管插管时可获得的血流储备分数。血流储备分数测量除了提供常规冠状动脉造影术所获得的解剖数据外，还将提供有价值的功能信息。本研究的目的是将首次通过分配算法与局部管腔容量测量技术相结合，开发一种定量计算分数流量储备的技术，并将其应用于心导管实验室。更具体地说，目的是：(1)研究动脉管腔体积之和可以用来预测进入冠状动脉树的最大充血血流量的假设。(2)探讨了利用血管造影图像测量的血流量和管腔体积之和来测量血流储备分数的假设。(3)分流量储备测量技术在人体心导管实验室的应用。这项研究的结果将为量化患者冠状动脉狭窄严重程度提供改进的生理学方法。这种定量技术可用于测量接受标准冠状动脉造影术的患者的血流储备分数。与公共卫生相关。血管造影术是确定冠状动脉解剖结构和评估动脉粥样硬化的标准方法。然而，使用目测估计来评估冠状动脉疾病和管腔狭窄的严重程度有一定的局限性。这些限制包括冠脉狭窄病变的主观视觉分级所导致的观察者的巨大变异性。尤其是在中度冠状动脉病变(30%-70%直径狭窄)的情况下，血管造影术在区分冠状动脉病变是否是胸痛的原因方面非常有限。由于标准冠状动脉造影术的主要局限性，需要一种功能测量狭窄严重程度的方法，如测量心导管插管时可获得的血流储备分数。血流储备分数测量除了提供常规冠状动脉造影术所获得的解剖数据外，还将提供有价值的功能信息。本研究的目的是开发一种结合局部血流和管腔容量测量技术来量化分数血流储备的技术，并将其在心导管实验室中实现。这项研究的结果将为量化患者冠状动脉狭窄程度提供改进的生理学方法。这种定量技术可用于测量接受标准冠状动脉造影术的患者的血流储备分数。

DESCRIPTION (provided by applicant): Coronary arteriography is the standard method for determination of coronary anatomy and assessment of atherosclerosis. However, there are definite limitations to the use of visual estimation to assess the severity of coronary artery disease and luminal stenosis. These limitations include the large intraobserver and interobserver variability that result from subjective visual grading of coronary stenotic lesions. This is especially true in the case of an intermediate coronary lesion (30%-70% diameter stenosis), where coronary arteriography is very limited in distinguishing ischemia-producing intermediate coronary lesions from non- ischemia-producing ones. Furthermore, pathologic findings have shown a lack of correlation between the severity of coronary stenosis as estimated from coronary arteriogram and the actual severity of stenotic lesions measured in postmortem hearts. Because of the major limitations of standard coronary arteriography, a method for functional measure of stenosis severity such as measurement of fractional flow reserve obtainable during cardiac catheterization is desirable. The fractional flow reserve measurement would provide valuable functional information in addition to the anatomical data obtained during routine coronary arteriography. The purpose of this research plan is to develop a technique for quantification of fractional flow reserve by combining the first pass distribution algorithm with regional lumen volume measurement technique and its implementation in the cardiac catheterization laboratory. More specifically, the aims are: (1) Investigation of the hypothesis that the sum of arterial lumen volume can be used to predict the maximum hyperemic blood flow into the coronary artery tree. (2) Investigation of the hypothesis that fractional flow reserve can be measured using the sum of lumen volume and measured blood flow from angiographic images. (3) Implementation of the fractional flow reserve measurement technique in the cardiac catheterization laboratory for human studies. The results of this research will provide improved physiological methods of quantitating coronary artery stenosis severity in patients. This quantification technique could be used to measure fractional flow reserve in patients undergoing standard coronary arteriography. PUBLIC HEALTH RELEVANCE. Angiography is the standard method for determination of coronary anatomy and assessment of atherosclerosis. However, there are definite limitations to the use of visual estimation to assess the severity of coronary artery disease and luminal stenosis. These limitations include the large observer variability that result from subjective visual grading of coronary stenotic lesions. This is especially true in the case of an intermediate coronary lesion (30%-70% diameter stenosis), where angiography is very limited in distinguishing whether a coronary lesions is the cause of chest pain. Because of the major limitations of standard coronary arteriography, a method for functional measure of stenosis severity such as measurement of fractional flow reserve obtainable during cardiac catheterization is desirable. The fractional flow reserve measurement would provide valuable functional information in addition to the anatomical data obtained during routine coronary arteriography. The purpose of this research plan is to develop a technique for quantification of fractional flow reserve by combining the regional blood flow and lumen volume measurement technique and its implementation in the cardiac catheterization laboratory. The results of this research will provide improved physiological methods for quantification of coronary artery stenosis severity in patients. This quantification technique could be used to measure fractional flow reserve in patients undergoing standard coronary arteriography.