Katritsis D, Webb-Peploe M M
Department of Cardiological Sciences, St. George's Hospital Medical School, London, England.
Am Heart J. 1990 Sep;120(3):537-43. doi: 10.1016/0002-8703(90)90007-k.
We applied an automated computer program capable of simultaneous geometric (through border detection) and densitometric quantitation of digital angiograms for evaluation of the results of percutaneous transluminal coronary angioplasty (PTCA) in different phases of the same cardiac cycle. Digital subtraction coronary angiograms (DSA) of 28 patients who had undergone PTCA to a total of 30 lesions, were analyzed in diastole, in systole, and in the middle of the cardiac cycle to test the variability in coronary quantitation resulting from random frame selection relative to cardiac phase. Before PTCA there was a low degree of variation between measurements obtained from the same lesion in different phases of the cardiac cycle, in both geometric (coefficient of variation between cardiac phases = 4.2%) and densitometric (coefficient of variation between cardiac phases = 5.1%) quantitation. After PTCA, however, there was a wider variation of values in different cardiac phases, which predominated in the densitometric measurements (coefficient of variation between cardiac phases = 33.6%, compared to 20.6% for geometric measurements). There was less agreement between different post-PTCA phases in densitometry, and discrepancies as large as 47% could occur in densitometric evaluation of the stenotic areas when different phases of the cycle were used. We concluded that border detection or densitometric quantitation of the postangioplasty lumens is subject to greater variation resulting from random frame selection relative to cardiac phase, as compared to preangioplasty assessment. This variation predominates in densitometric quantitation, which seems to be dependent not only on the radiographic projection but also on the cardiac phase. The usefulness of densitometric techniques for the evaluation of PTCA results appears to be questionable.
我们应用了一种自动化计算机程序，该程序能够对数字血管造影进行同步几何测量（通过边界检测）和密度定量分析，以评估同一心动周期不同阶段经皮腔内冠状动脉成形术（PTCA）的结果。对28例患者共30处病变的数字减影冠状动脉造影（DSA）在舒张期、收缩期和心动周期中间进行分析，以测试相对于心动周期随机选择帧导致的冠状动脉定量变异性。在PTCA之前，同一病变在心动周期不同阶段获得的测量值之间，几何测量（心动周期之间的变异系数 = 4.2%）和密度测量（心动周期之间的变异系数 = 5.1%）的变异程度都较低。然而，PTCA后，不同心动周期阶段的值变化更大，这在密度测量中更为明显（心动周期之间的变异系数 = 33.6%，而几何测量为20.6%）。密度测量中PTCA后不同阶段之间的一致性较差，当使用心动周期的不同阶段时，狭窄区域的密度测量评估中可能出现高达47%的差异。我们得出结论，与血管成形术前评估相比，血管成形术后管腔的边界检测或密度定量分析因相对于心动周期随机选择帧而受到更大的变异影响。这种变异在密度定量分析中占主导地位，密度定量分析似乎不仅取决于放射投影，还取决于心动周期阶段。密度测量技术用于评估PTCA结果的实用性似乎值得怀疑。
