64层双源螺旋CT与血管内超声对冠状动脉粥样硬化斑块性质的对比研究

目的对比冠状动脉血管内超声(IVUS)与64层双源螺旋CT(64-sCT)检查对冠状动脉粥样硬化斑块特征判定的准确性。方法选择35例不稳定性心绞痛患者行64-sCT与IVUS检查,分别测定同一病变同一位置的血管横截面积、管腔横截面积、斑块负荷;采用IVUS判定斑块性质,64-sCT测定其CT值。结果 45支血管(左前降支23支;左回旋支15支;右冠状动脉7支)的72个不同截面行IVUS与64-sCT检查,在可用于评估的68个截面中,64-sCT对51个存在斑块的截面,正确显示49个存在斑块(敏感性96%),对提示17个无斑块的截面,正确显示16个无斑块存在(特异性94%)。脂质斑块(25±14)HU、纤维斑块(90±20)HU、钙化斑块(530±185)HU;混合斑块中,钙化-脂质斑块(540±175)HU、钙化-纤维斑块(540±195)HU、纤维-脂质斑块(91±22)HU。纤维-脂质斑块与纤维斑块差异无统计学意义;钙化-脂质斑块、钙化-纤维斑块与钙化斑块差异无统计学意义。靶血管外弹力膜截面积、管腔截面积、斑块负荷、狭窄程度之间差异无统计学意义。结论对比IVUS与64-sCT检查能够定性及定量分析冠状动脉粥样硬化斑块,但其精确度仍有一定的限制。     

Greater late lumen loss after successful coronary balloon angioplasty in the proximal left anterior descending coronary artery is not explained by extent of vessel wall damage or plaque burden

OBJECTIVES: We investigated whether the greater late lumen loss after coronary balloon angioplasty in the proximal left anterior descending artery (P-LAD) compared with that in other segments might be related to differences in vascular dimensions or morphology as determined by angiography and intravascular ultrasound imaging. BACKGROUND: The greater late lumen loss after angioplasty in the P-LAD that has been observed in several studies has not been explained. METHODS: We studied 178 patients and 194 coronary artery lesions by quantitative angiography and 30 MHz intravascular ultrasound imaging after successful balloon angioplasty. Vessel wall morphology was compared among three proximal and three nonproximal segments. Follow-up quantitative angiography for late lumen loss calculation was performed in 168 lesions. Multivariate analysis was used to determine predictors of late lumen loss. RESULTS: Absolute and relative late loss were significantly greater at the P-LAD compared with the pooled group of other segments (0.42 +/- 0.60 mm vs. 0.10 +/- 0.48 mm, p = 0.0008 and 0.14 +/- 0.24 vs. 0.03 +/- 0.17, p < 0.001). Also, a greater percentage of calcific lesions (65% vs. 44%, p = 0.034), a lower incidence of rupture (51% vs. 74%, p = 0.009) and a larger reference segment plaque area (5.4 +/- 2.2 mm2 vs. 4.7 +/- 1.9 mm2, p = 0.05) were found in the P-LAD. In multivariate analysis however, these variables were not predictive of late loss. CONCLUSIONS: Greater late lumen loss after coronary balloon angioplasty of the P-LAD is not explained by differences in atherosclerotic plaque burden or in vessel wall damage.     

冠状动脉内超声成像对斑块形态、临床综合征及冠状动脉造影的对比研究

目的研究血管内超声对冠状动脉内斑块形态的分析，以及斑块形态与患者临床表现的关系。方法对４２例冠心病患者行冠状动脉造影及冠状动脉内超声成像检查（ＩＣＵＳ），定性分析斑块形态和性质，并与冠状动脉造影对比。患者根据临床特征分为不稳定型心绞痛组（Ａ组）和稳定型心绞痛组（Ｂ组）。结果冠状动脉造影发现，冠状动脉狭窄程度两组比较无显著性差异，而对比两组超声斑块形态和性质发现Ａ组病变以软斑块多见（Ａ组６６％，Ｂ组３１％，Ｐ＜０．０５），Ｂ组则以纤维斑块更常见（Ｂ组５４％，Ａ组１７％，Ｐ＜０．０５）。结论ＩＣＵＳ对病变形态和性质的分类与临床综合征关系更密切。     

The presence of a calcific plaque in the common carotid artery as a predictor of coronary atherosclerosis

Many contradictory reports have been published investigating the relationship between coronary artery disease (CAD) and the increased intima-media thickness (IMT) in the common carotid artery (CCA). However, only a limited number of studies evaluate the relationship between CAD and CCA disease as reflected by both the plaque morphology (fibrous and calcific plaques) and IMT. We have studied the associations between CAD and the wall morphology of CCA by B-mode ultrasound (US). One hundred and forty-four subjects, whose angiography was planned on the basis of suspected CAD, were included into the study. The patients were divided into 4 groups on the basis of B-mode US findings; Group I: normal, Group II: increased IMT (IMT >/= 0.8 mm and plaque absent), Group III: fibrous plaque, Group IV: calcific plaque. Coronary artery disease was diagnosed in 63 patients. A statistically significant correlation was found between CAD and CCA wall morphology (r =0.42, CI (95%) = 0.30-0.51, p<0.001). Positive predictive values were 45.0%, 48.4%, and 75.0% in patients with increased IMT, fibrous plaque, and calcific plaque, respectively. None of the women with normal CCA wall morphology had significant coronary artery lesion. With respect to the normal group, the risk for CAD increased by 4.3 fold with the existence of fibrous plaque (p=0.02) and by 9.9 fold with the existence of calcific plaque (p<0.001). It has been shown that the CCA wall morphology determined by B-mode US is correlated with CAD in patients with chest pain, and the presence of calcific plaque is a better predictor for CAD than that of fibrous plaque and increased IMT. Women with chest pain and normal CCA wall morphology may not need coronary angiography.     

不稳定型心绞痛患者的血管内超声分析

目的:应用血管内超声(IVUS)探讨不稳定型心绞痛(UAP)患者的斑块形态学特点。方法:经冠状动脉造影和IVUS检查的冠心病患者57例,其中稳定型心绞痛(SAP)21例,UAP 36例,根据斑块回声的强度,将斑块分为软斑块、纤维斑块、钙化斑块、混合斑块和斑块破裂等,分析比较UAP和SAP患者的斑块的形态学特点。结果:IVUS发现软斑块的比例在SAP和UAP患者中分别为47.6%和75.0%,纤维斑块的比例分别为52.4%和25.0%,斑块破裂分别为0和30.6%,钙化斑块分别为52.4%和19.4%(均P<0.05)。结论:IVUS显示UAP的斑块形态学特点主要表现为软斑块和斑块破裂。     

16排螺旋CT对冠状动脉斑块的诊断价值

目的探讨16排螺旋CT（16-mulddetector spiral computed tomography,16-MDCT）检测和区分冠状动脉斑块的准确性。方法对2005年8月至2006年3月68例拟诊为冠心病的患者先行16-MDCT检查,4天内再行定量冠状动脉造影（QCA）和血管内超声（IVUS）检查,冠状动脉血管腔直径狭窄（DS）≥50％定义为有意义的狭窄,分别测量斑块的CT密度,单位为CT值（Hounsfield units,HU）,根据冠状动脉斑块的CT值区分斑块性质并作出分类：（1）软斑块：CT值为≤50HU;（2）纤维斑块（中等斑块）：CT值为50—119HU;（3）钙化斑块≥120HU。结果在112段16-MDCT和QCA均诊断为冠状动脉狭窄≥50％的病变中,其敏感性为91．8％（112／122）,特异性为97．8％（556／568）,共96段有意义的狭窄病变纳入研究,分别位于左前降支57段,左回旋支17段,右冠状动脉14段,左主干8段。IVUS发现软斑块21个（21．9％）、纤维斑块36个（37．5％）、钙化斑块38个（39．5％）,混合性斑块（纤维钙化斑块）1个（1．1％）,16-MDCT发现软斑块20个,平均CT值（11±36）HU（-27～42HU）、纤维斑块37个,平均CT值（83±20）Hu（58—105HU）、钙化斑块39个,平均CT值（292±80）HU（167—530HU）,差异有统计学意义（P〈0．05）。结论无创性16排螺旋CT冠状动脉成像技术不仅可诊断冠状动脉狭窄病变,同时对区分钙化斑块及非钙化斑块有较高的诊断价值。     

Plaque characterization of atherosclerotic coronary arteries by intravascular ultrasound

Intravascular ultrasound provides cross-sectional images of arteries and enables accurate delineation of lumen dimensions and wall structure. Moreover, ultrasound characterization of atherosclerotic plaque subtypes may have important implications in determining the natural history and the clinical outcome of patients with coronary artery disease. The reliability of intravascular ultrasound to differentiate plaque morphology subtypes was studied in 60 coronary segments excised from 33 coronary arteries obtained from 17 patients at necropsy. Ultrasound was performed with a 25-MHz transducer mounted on the distal end of a rigid probe that was rotated manually inside the lumen artery. Plane film radiography was also performed to establish the presence of calcific deposits. A total of 82 histologic transverse sections corresponding to 82 ultrasound imaging sites were studied from the 60 coronary segments. Of the first 54 images, 36 were fibrous plaques and yielded dense homogenous echo reflections, 6 had discrete areas of lipid that were less echogenic and 12 had calcific deposits that cast echo-free shadows beyond areas of intense echo reflections. The predictive accuracy of evaluating plaque composition in the remaining 28 ultrasound imaging sites was 96%. Thus, anatomical structure of coronary arteries and composition of atherosclerotic lesions can be assessed accurately with intravascular ultrasound and may have potential for better understanding of the atherosclerotic process and provide guidance to interventional procedures.     

冠状动脉成形术中正常参考段的血管内超声研究

目的　应用血管内超声研究冠心病介入治疗时“正常”参考段的病变情况。方法　 12 0例冠心病患者行介入治疗 ,术中血管内超声 (IVU S)评价造影显示正常的参考血管段。结果　 (1)冠状动脉造影显示“正常”的参考段仅10 .8%经 IVUS证实无明显病变 ;(2 )参考段平均面积狭窄百分比为 (4 2 .6± 11.9) % ,参考段狭窄程度与目标病变的狭窄程度呈轻度正相关 (r=0 .32 7,P<0 .0 0 1) ;(3)参考段的病变中纤维斑块及钙化斑块较少而脂质斑块较多。结论　造影显示的“正常”参考段冠状动脉常存在不同程度的粥样硬化病变。     

Assessment of coronary arterial plaque by optical coherence tomography

The purpose of this study was to analyze the ability of optical coherence tomography (OCT) to identify coronary arterial plaque diagnosed by histologic examination. We examined 166 sections from 108 coronary arterial segments of 40 consecutive human cadavers (24 men and 16 women; mean age 74 +/- 7 years). The plaque type was classified as fibrous (n = 43), fibrocalcific (n = 82), or lipid-rich (n = 41). The accuracy of OCT and intravascular ultrasound (IVUS) in characterizing the plaque type was studied, with the histologic consensus diagnosis serving as the gold standard. OCT, as well as IVUS, had high sensitivity and specificity for characterizing the different types of atherosclerotic plaque. OCT had a higher sensitivity for characterizing lipid-rich plaques than IVUS (85% vs 59%, p = 0.03). In conclusion, the high resolution of OCT permitted evaluation of lipid-rich plaques more accurately than IVUS.     

64层CT与血管内超声对冠状动脉粥样斑块的定性和定量评估的对照研究

目的 对照血管内超声（intravascular ultrasound,IVUS）评价64层CT对冠状动脉粥样斑块的定性检测和定量分析。方法 2005年7月至10月连续纳入12例拟行PCI的稳定性心绞痛患者进行研究。所有患者术前接受64层CT的冠状动脉成像,术中行三支冠状动脉（左前降支、回旋支和右冠状动脉）的IVUS检查。结果 共对31支血管（左前降支12支,回旋支10支,右冠状动脉9支）,88个节段进行了64层CT和IVUS的对比检查,其中64层CT可评价节段为68个。在IVUS检测到的51个有斑块节段中,64层CT检测出47个（敏感性92％）,在17个IVUS判断为无斑块的节段中,64层CT判断16个为无斑块（特异性94％）。64层CT测量的斑块面积和IVUS测量的斑块面积相关（r=0．53,P〈0．01）,但是高估了斑块面积[（9．09±3．89）mm。比（6．80±2．81）mm^2,P〈0．01]。64层CT在43个IVUS测定的低回声成分中检出30个为低密度成分,平均CT值67．39HU。结论 冠状动脉无严重钙化时,64层CT可准确检测冠状动脉近中段粥样斑块。64层CT测量的斑块面积虽然和IVUS测量结果相关,但准确测量受限。     

稳定型与不稳定型心绞痛患者冠状动脉内超声的对比研究

目的　应用血管内超声对稳定与不稳定型心绞痛患者的冠状动脉病变进行对比分析。方法　 10 5例同时进行了选择性冠状动脉造影和血管内超声的患者 ,按心绞痛性质分为稳定型心绞痛组 (SA组 )和不稳定型心绞痛组 (UA组 ) ,比较两组患者冠状动脉狭窄程度、斑块形态和性质的差异。结果　两组冠状动脉造影显示的病变血管及狭窄程度差异无显著性 ;血管内超声显示 ,UA组病变以脂质斑块多见 ,SA组病变则以纤维斑块和钙化斑块更常见 ;SA组病变钙化的程度较UA组严重 ;UA组病变自发性内膜撕裂和血栓形成的比例明显高于SA组。结论　血管内超声显示 ,稳定型与不稳定型心绞痛患者的冠状动脉病变在形态和性质上存在明显差异。     

Characteristics of atherosclerotic plaque distribution in coronary artery bifurcations: an intravascular ultrasound analysis

OBJECTIVE: Vessel bifurcations are prone to atherosclerotic plaque accumulation. Using volumetric intravascular ultrasound analysis, we investigated atheroma distribution at human coronary bifurcations in vivo. METHODS: We analyzed plaque distribution in 49 left anterior descending coronary artery-diagonal and 20 left circumflex coronary artery-obtuse marginal bifurcations with <50% angiographic stenosis. Cross-sections were analyzed at 1 mm intervals in segments 5 mm proximal and distal from the bifurcation. Planimetry of the lumen and external elastic membrane (EEM) was performed and plaque thickness measured at four different points relative to the branch: 0 degrees, 90 degrees, 180 degrees and 270 degrees. EEM, lumen and plaque volume and percentage plaque burden (plaque volume/EEM volume) were calculated in the proximal and distal segments. The side-branch take-off angle was analyzed in the cross-sectional images. RESULTS: Volumetric analysis showed that EEM, lumen and plaque were larger (P<0.001) in proximal segments than distal segments, whereas percent plaque burden was similar in these segments. Plaque accumulated on the opposite wall to the flow divider. Plaque distribution tended to be more eccentric in distal segments (P=0.05) compared to proximal segments. In 26 of 69 lesions, an asymmetric side-branch take-off was found and was associated with asymmetric plaque distribution compared to those lesions that had a symmetric side-branch take-off (P<0.01). CONCLUSION: We found characteristic patterns of plaque distribution at coronary bifurcations. Proximal segments demonstrated larger plaque volume than distal segments, despite similar percentages of plaque burden. Plaque volume accumulated opposite to the flow divider, especially in distal segments. The side-branch take-off angle in the cross-sectional plane influenced the plaque distribution in bifurcation lesions.     

Sources of error and interpretation of plaque morphology by optical coherence tomography

This study was performed to assess the strengths and weaknesses of optical coherence tomography (OCT) intravascular imaging in identifying plaque morphology. Seventy-nine postmortem human coronary arterial sections classified as fibrous-cap atheromas, calcific plaques, fibrous plaques, and complicated lesions were studied. OCT was able to identify 45% of fibrous-cap atheromas (kappa=0.27, p<0.01), 68% of fibrocalcific plaques (kappa=0.40, p<0.001), 83% of fibrous plaques (kappa=0.37, p<0.001), and 100% of complicated lesions (all thrombi; kappa=1, p<0.001). Misinterpretation was caused mainly by the low OCT signal penetration, which could not detect lipid pools or calcium behind thick fibrous caps, and by an inability to distinguish calcium deposits from lipid pools or the opposite. Lesions with thick (>150 microm) caps were histologically identified as 25 thick fibrous-cap atheromas, 8 fibrocalcific plaques, and 5 fibrous plaques; all these lesions were relatively "stable." In contrast, lesions with fibrous caps<150 microm were either vulnerable or stable lesions (11 thin-fibrous-cap atheromas and 11 fibrocalcific plaques). In conclusion, although OCT images may give an indication of the overall composition of large homogenous signal-poor regions, such as lipids or calcified areas, they could be unreliable in differentiating areas with heterogenous compositions. OCT may easily recognize relatively stable lesions.     

Plaque ruptures in stable angina pectoris compared with acute coronary syndrome

BackgroundPlaque rupture is more frequently observed in patients with acute coronary syndrome (ACS) rather than in patients with stable angina pectoris (SAP). Consequently, studies regarding plaque rupture, which occurred in SAP patients, are rare. Therefore, we evaluated the frequency and axial location of plaque ruptures in SAP patients and compared them with those in ACS patients.MethodsThree hundred ninety-two patients (231 ACS and 161 SAP patients) who were scheduled for coronary intervention underwent three-vessel intravascular ultrasound (IVUS) study. IVUS criteria for plaque rupture were a plaque contained a cavity that communicated with the lumen with an overlying residual fibrous cap fragment. Using motorized IVUS transducer pullback in all three coronary arteries, the distance between each coronary plaque rupture segment and the respective coronary ostium was measured.ResultsPlaque ruptures were detected in 206 of 392 patients who underwent three-vessel intravascular ultrasound examination. At least one plaque rupture in any coronary artery was noted in 48 (30%) SAP and 158 (68%) ACS patients (p < 0.001). In both ACS and SAP patients, plaque ruptures were clustered mainly in the proximal segments of the left anterior descending artery and in the proximal and distal segments of the right coronary artery.ConclusionsAt least one plaque rupture in any coronary artery was noted in 30% of SAP patients. Like in ACS patients, plaque ruptures were clustered mainly in the proximal segments of the left anterior descending artery and in the proximal and distal segments of the right coronary artery in SAP patients.     

Histological characteristics of plaque with ultrasonic attenuation: a comparison between intravascular ultrasound and histology

OBJECTIVES: Intermediate echogenic plaque without acoustic shadow on intravascular ultrasound (IVUS) imaging has been recognized as fibrous plaque. Such echogenic plaque with ultrasonic attenuation may have higher risk for distal flow disturbance (slow flow/no-reflow) during percutaneous coronary intervention. However, histological evaluation of plaque with ultrasonic attenuation has not been performed. This study evaluated the histological characteristics of plaque with ultrasonic attenuation assessed by IVUS. METHODS: By using IVUS, 36 samples of human cadaveric coronary arterial echogenic plaque (percentage plaque area > 40%) without calcium were selected, and classified into the attenuation group; plaque with ultrasonic attenuation, and the non-attenuation group; plaque without attenuation. These plaques were classified for fibrous, fibrofatty, calcium, and necrotic core areas by histological examination. RESULTS: True fibrous plaque was found in 91.7% of the non-attenuation group, but only 68.0% of the attenuation group (p < 0.01) . On the other hand, the percentage fibrofatty and necrotic core plaque areas in the attenuation group were significant larger than those in the non-attenuation group (fibrofatty: 16.3 +/- 13.8% vs. 2.7 +/- 3.1%, p < 0.01; necrotic core: 13.0 +/- 19.4% vs. 3.9 +/- 8.0%, p = 0.03). CONCLUSIONS. Plaque with ultrasonic attenuation contains more fibrofatty tissue and necrotic core compared to fibrous plaque without attenuation.     

Ultrasound-assessed non-culprit and culprit coronary vessels differ by age and gender

AIM: To investigate age-and gender-related differences in non-culprit versus culprit coronary vessels assessed with virtual histology intravascular ultrasound (VH-IVUS). METHODS: In 390 patients referred for coronary angiography to a single center (Luzerner Kantonsspital, Switzerland) between May 2007 and January 2011, 691 proximal vessel segments in left anterior descending, circumflex and/or right coronary arteries were imaged by VH-IVUS. Plaque burden and plaque composition(fibrous, fibro-fatty, necrotic core and dense calcium volumes) were analyzed in 3 age tertiles, according to gender and separated for vessels containing non-culprit or culprit lesions. To classify as vessel containing a culprit lesion, the patient had to present with an acute coronary syndrome, and the VH-IVUS had to be performed in a vessel segment containing the culprit lesion according to conventional coronary angiography. RESULTS: In non-culprit vessels the plaque burden increased significantly with aging (in men from 37% ± 12% in the lowest to 46% ± 10% in the highest age tertile, P < 0.001; in women from 30% ± 9% to 40% ± 11%, P < 0.001); men had higher plaque burden than women at any age (P < 0.001 for each of the 3 age tertiles). In culprit vessels of the lowest age tertile, plaque burden was significantly higher than that in non- culprit vessels (in men 48% ± 6%, P < 0.001 as compared to non-culprit vessels; in women 44% ± 18%, P = 0.004 as compared to non-culprit vessels). Plaque burden of culprit vessels did not significantly change during aging (plaque burden in men of the highest age tertile 51% ± 9%, P = 0.523 as compared to lowest age tertile; in women of the highest age tertile 49% ± 8%, P = 0.449 as compared to lowest age tertile). In men, plaque morphology of culprit vessels became increasingly rupture-prone during aging (increasing percentages of necrotic core and dense calcium), whereas plaque morphology in non-culprit vessels was less rupture-prone and remained constant during aging. In women, necrotic core in non-culprit vessels was very low at young age, but increased during aging resulting in a plaque morphology that was very similar to men. Plaque morphology in culprit vessels of young women and men was similar. CONCLUSION: This study provides evidence that age-and gender-related differences in plaque burden and plaque composition significantly depend on whether the vessel contained a non-culprit or culprit lesion.     

Characterization of coronary atherosclerotic plaques by multidetector computed tomography

Multidetector computed tomography (MDCT) provides 3-dimensional noninvasive visualization of the coronary arterial tree. We compared MDCT with intravascular ultrasound (IVUS) for assessment of severity of coronary artery stenosis and composition of atherosclerotic plaques in 40 patients (32 men; mean age 52 years, range 33 to 86) with documented coronary artery disease. Cross-sectional images obtained at 10-mm increments were assessed for percent decrease in luminal area. Atherosclerotic plaques were classified by IVUS as soft, fibrous, or calcified. On the matched multidetector computed tomograms, regions of interest of 1 to 3 mm in diameter were placed inside each plaque, and tissue contrast was measured in Hounsfield units. Obstructive coronary artery disease was found in 50 segments by IVUS and 57 segments by MDCT. Sensitivity for detecting obstruction >50% was 86.0% (95% confidence interval 72.6 to 93.7) and specificity was 90.2% (95% confidence interval 83.9 to 94.4). In total, 276 plaques were examined by IVUS and MDCT. There were 188 soft plaques (68.2%), 45 fibrous plaques (16.2%), and 43 calcified plaques (15.5%). Multidetector computed tomographic tissue contrast of soft, fibrous, and calcified plaques were 71.5 +/- 32.1, 116.3 +/- 35.7, and 383.3 +/- 186.1, respectively (p <0.001). Using a cut-off value of 185 HU, 273 of 276 plaques (99%) were correctly classified as calcified or noncalcified plaques. Using a cut-off value of 88 HU, 192 of 233 noncalcified plaques (82%) were correctly classified as fibrous or soft plaques. In conclusion, our data indicate that MDCT can provide important information concerning the composition of atherosclerotic plaques in addition to detecting luminal obstruction.     

Noninvasive tissue characterization of coronary arterial plaque by 16-slice computed tomography in acute coronary syndrome

Noninvasive characterization of coronary plaques is challenging for cardiologists. The authors' goal was to explore the clinical feasibility of newly developed 16-slice computed tomography (CT) in tissue characterization of coronary arterial plaques in patients with acute coronary syndrome. Sixteen patients with acute coronary syndrome underwent 16-slice CT (Aquillion, Toshiba) and coronary arteriography with intravascular ultrasound (IVUS) within 7 days. Twenty-three plaques were classified by IVUS according to plaque echogenicity: 6 soft plaques, 11 intermediate plaques, and 6 calcified plaques. Mean (+/- SD) CT numbers (Hounsfield units [HU]) of these 3 types of plaques were 50.6 +/-14.8 HU, 131 +/-21.0 HU, and 721 +/-231 HU, respectively. Sixteen-slice CT facilitates noninvasive tissue characterization of coronary arterial plaques.     

Comparison of intravascular ultrasound, external ultrasound and digital angiography for evaluation of peripheral artery dimensions and morphology

Validation of catheter-based intravascular ultrasound imaging has been based on comparisons with histology and digital angiography, each of which may have limitations in the assessment of arterial size and morphology. External, high-frequency ultrasound can accurately determine vessel dimensions and morphology and because, like ultravascular ultrasound, it also provides cross-sectional arterial ultrasound images, it may be a more appropriate technique for the in vivo comparison of arterial dimensions and morphology determined by intravascular ultrasound. Thus, intravascular ultrasound, external 2-dimensional ultrasound, Doppler color-flow imaging and digital angiography were compared for assessment of arterial dimensions and wall morphology at 29 femoral artery sites in 15 patients. Intravascular ultrasound and the other 3 imaging modalities correlated well in determination of lumen diameter (2-dimensional, r = 0.98, standard error of the estimate [SEE] = 0.14; Doppler color flow, r = 0.91, SEE = 1.11; angiography, r = 0.95, SEE = 0.91) and cross-sectional area (2-dimensional, r = 0.97, SEE = 0.04; Doppler color flow, r = 0.92, SEE = 0.14; angiography, r = 0.96, SEE = 0.08). However, lumen size measured by Doppler color flow was consistently smaller than that measured by the other 3 imaging modalities. Intravascular ultrasound detected arterial plaque at 15 sites, 5 of which were hypoechoic (soft) and 10 hyperechoic with distal shadowing (hard). Plaque was identified at 12 of 15 sites by Z-dimensional imaging (p = 0.30 vs intravascular ultrasound), but at only 6 of 15 sites by angiography (p = 0.003 vs intravascular ultrasound), only 1 of which was thought to be calcified plaque.(ABSTRACT TRUNCATED AT 250 WORDS)     

The influence of diabetes mellitus on plaque volume and vessel size in patients undergoing percutaneous coronary intervention

We evaluated the influence of diabetes on plaque volume and vessel size at a reference segment in diabetic patients undergoing percutaneous coronary intervention using both angiograms and quantitative intravascular ultrasound. A total of 344 patients with 449 de novo coronary lesions including 97 diabetics (133 lesions) who underwent elective percutaneous coronary intervention under intravascular ultrasound guidance were included in this study. Eleven diabetic patients (19 lesions) received insulin and 52 patients (77 lesions) oral hypoglycemic drugs. The other 34 patients (37 lesions) received diet/exercise therapy alone. We measured vessel area (VA) and lumen area (LA) at proximal and distal reference segments by intravascular ultrasound, which were averaged. Plaque area (VA-LA) and % plaque area (100 x plaque area/VA) were subsequently calculated. Although VA was similar between diabetic and non-diabetic patients (13.46 +/- 4.49 mm2 in diabetics versus 14.11 +/- 5.24 mm2 in non-diabetics, P = 0.214), LA was smaller (6.51 +/- 2.63 mm2 versus 7.38 +/- 3.08 mm2, P = 0.004) and % PA was larger (50.4 +/- 11.7 versus 46.5 +/- 11.3, P < 0.001) in diabetic patients, especially the group receiving a hypoglycemic drug or insulin. VA, LA, and % PA were similar between patients with and without insulin treatment. These results potentially might cause undersized device selection without intravascular ultrasound guidance.