To determine the rate of subsequent invasive coronary angiography (ICA) and revascularization in relation to computed tomography coronary angiography (CTA) results. In addition, independent... Show moreTo determine the rate of subsequent invasive coronary angiography (ICA) and revascularization in relation to computed tomography coronary angiography (CTA) results. In addition, independent determinants of subsequent ICA and revascularization were evaluated. CTA studies were performed using a 64-row (n = 413) or 320-row (n = 224) multidetector scanner. The presence and severity of CAD were determined on CTA. Following CTA, patients were followed up for 1 year for the occurrence of ICA and revascularization. A total of 637 patients (296 male, 56 ± 12 years) were enrolled and 578 CTA investigations were available for analysis. In patients with significant CAD on CTA, subsequent ICA rate was 76 %. Among patients with non-significant CAD on CTA, subsequent ICA rate was 20 % and among patients with normal CTA results, subsequent ICA rate was 5.7 % (p < 0.001). Of patients with significant CAD on CTA, revascularization rate was 47 %, as compared to a revascularization rate of 0.6 % in patients with non-significant CAD on CTA and no revascularizations in patients with a normal CTA results (p < 0.001). Significant CAD on CTA and significant three-vessel or left main disease on CTA were identified as the strongest independent predictors of ICA and revascularization. CTA results are strong and independent determinants of subsequent ICA and revascularization. Consequently, CTA has the potential to serve as a gatekeeper for ICA to identify patients who are most likely to benefit from revascularization and exclude patients who can safely avoid ICA. Show less
Velzen, J.E. van; Graaf, M.A. de; Ciarka, A.; Graaf, F.R. de; Schalij, M.J.; Kroft, L.J.; ... ; Wall, E.E. van der 2012
Previous angiographic studies have shown that almost two-thirds of vulnerable plaques are located in non-obstructive lesions. Possibly, the maximum necrotic core (Max NC) area is not always... Show morePrevious angiographic studies have shown that almost two-thirds of vulnerable plaques are located in non-obstructive lesions. Possibly, the maximum necrotic core (Max NC) area is not always identical to the site of most severe stenosis. Therefore, the purpose of this study was to evaluate the potential difference in location between the maximum necrotic core area and the site of most severe narrowing as assessed by virtual histology intravascular ultrasound (VH IVUS). Overall, 77 patients (139 vessels) underwent VH IVUS. The Max NC site was defined as the cross section with the largest necrotic core area per vessel. The site of most severe narrowing was defined as the minimum lumen area (MLA). Per vessel, the distance from both the Max NC site and MLA site to the origo of the coronary artery was evaluated. In addition, the presence of a virtual histology-thin cap fibroatheroma (VH-TCFA) was assessed. The mean difference (mm) between the MLA site and Max NC site was 10.8 ± 20.6 mm (p < 0.001). Interestingly, the Max NC site was located at the MLA site in seven vessels (5%) and proximally to the MLA site in 92 vessels (66%). Importantly, a higher percentage of VH-TCFA was demonstrated at the Max NC site as compared to the MLA site (24 vs. 9%, p < 0.001). In conclusion, the present findings demonstrate that the Max NC area is rarely at the site of most severe narrowing. Most often, the Max NC area is located proximal to the site of most severe narrowing. Show less
During the past few years CTA has rapidly developed into a versatile non-invasive imaging modality. While imaging of the coronary arteries to determine or rule out the presence of stenosis will... Show moreDuring the past few years CTA has rapidly developed into a versatile non-invasive imaging modality. While imaging of the coronary arteries to determine or rule out the presence of stenosis will remain one of the main indications, additional information on plaque severity and composition can be obtained. The improvements in technology (faster gantry rotation times, an increasing number of detectors, volumetric image acquisition) and consequential improvement in image quality have resulted in advances in the characterization of coronary atherosclerosis and vulnerable plaque. Interestingly, the diagnostic performance of CTA was superior in the evaluation of presence or absence of clinically relevant atherosclerosis as compared to the evaluation of signifi cant stenosis. Regarding plaque observations with the novel 320-row CTA scanner, the results showed good agreement to relative plaque composition on invasive VH IVUS. Moreover, mixed plaques on 320-row CTA paralleled the more vulnerable plaque on VH IVUS. In addition, lesions with spotty calcifi cations and positive remodeling on CTA were associated with a higher percentage necrotic core and a higher prevalence of vulnerable plaques. Accordingly, evaluation of spotty calcifi cations and remodeling on CTA may be valuable markers for plaque vulnerability. The relation between characterization of atherosclerosis on CTA and its effect on clinical management was also evaluated. As a result of rapid developments in coronary CTA technology, high diagnostic accuracies of 320-row CTA for detecting coronary stenosis were obtained in patients with stable chest pain complaints as well as in patients presenting with acute chest pain. In addition, although a zero calcium score has important prognostic value, patients with acute coronary syndrome and zero calcium had increased plaque burden as well as increased vulnerability as compared to patients with stable chest pain. Accordingly, absence of coronary calcifi cation did not exclude the presence of clinically relevant and potentially vulnerable atherosclerotic plaque burden in patients with acute coronary syndrome. Lastly, in addition to the degree of stenosis, CTA variables of atherosclerosis describing plaque extent, composition and location were predictive of the presence of ischemia on myocardial perfusion imaging. Possibly, these results may allow a more refi ned and individualized assessment of patients undergoing CTA imaging and provide the basis for the development of an algorithm to improve identifi cation of patients requiring more aggressive therapy or intervention. Show less
AimsPrevious studies have used semi-automated approaches for coronary plaque quantification on multi-detector row computed tomography (CT), while an automated quantitative approach using a... Show moreAimsPrevious studies have used semi-automated approaches for coronary plaque quantification on multi-detector row computed tomography (CT), while an automated quantitative approach using a dedicated registration algorithm is currently lacking. Accordingly, the study aimed to demonstrate the feasibility and accuracy of automated coronary plaque quantification on cardiac CT using dedicated software with a novel 3D coregistration algorithm of CT and intravascular ultrasound (IVUS) data sets.Methods and resultsPatients who had undergone CT and IVUS were enrolled. Automated lumen and vessel wall contour detection was performed for both imaging modalities. Dedicated automated quantitative software (QCT) with a unique registration algorithm was used to fuse a complete IVUS run with a CT angiography volume using true anatomical markers. At the level of the minimal lumen area (MLA), percentage lumen area stenosis, plaque burden, and degree of remodelling were obtained on CT. Additionally, mean plaque burden was assessed for the whole coronary plaque. At the identical level within the coronary artery, the same variables were derived from IVUS. Fifty-one patients (40 men, 58 ± 11 years, 103 coronary arteries) with 146 lesions were evaluated. Quantitative computed tomography and IVUS showed good correlation for MLA (n = 146, r = 0.75, P < 0.001). At the level of the MLA, both techniques were well-correlated for lumen area stenosis (n = 146, r = 0.79, P < 0.001) and plaque burden (n = 146, r = 0.70, P < 0.001). Mean plaque burden (n = 146, r = 0.64, P < 0.001) and remodelling index (n = 146, r = 0.56, P < 0.001) showed significant correlations between QCT and IVUS.ConclusionAutomated quantification of coronary plaque on CT is feasible using dedicated quantitative software with a novel 3D registration algorithm. Show less
Velzen, J.E. van; Graaf, M.A. de; Ciarka, A.; Graaf, F.R. de; Schalij, M.J.; Kroft, L.J.; ... ; Wall, E.E. van der 2012
Multidetector computed tomography angiography (CTA) provides information on plaque extent and stenosis in the coronary wall. More accurate lesion assessment may be feasible with CTA as compared to... Show moreMultidetector computed tomography angiography (CTA) provides information on plaque extent and stenosis in the coronary wall. More accurate lesion assessment may be feasible with CTA as compared to invasive coronary angiography (ICA). Accordingly, lesion length assessment was compared between ICA and CTA in patients referred for CTA who underwent subsequent percutaneous coronary intervention (PCI). 89 patients clinically referred for CTA were subsequently referred for ICA and PCI. On CTA, lesion length was measured from the proximal to the distal shoulder of the plaque. Quantitative coronary angiography (QCA) was performed to analyze lesion length. Stent length was recorded for each lesion. In total, 119 lesions were retrospectively identified. Mean lesion length on CTA was 21.4 ± 8.4 mm and on QCA 12.6 ± 6.1 mm. Mean stent length deployed was 17.4 ± 5.3 mm. Lesion length on CTA was significantly longer than on QCA (difference 8.8 ± 6.7 mm, P < 0.001). Moreover, lesion length visualized on CTA was also significantly longer than mean stent length (CTA lesion length-stent length was 4.2 ± 8.7 mm, P < 0.001). Lesion length assessed by CTA is longer than that assessed by ICA. Possibly, CTA provides more accurate lesion length assessment than ICA and may facilitate improved guidance of percutaneous treatment of coronary lesions. Show less
Graaf, F.R. de; Velzen, J.E. van; Witkowska, A.J.; Schuijf, J.D.; Bijl, N. van der; Kroft, L.J.; ... ; Wall, E.E. van der 2011
A considerable number of patients with an acute coronary syndrome (ACS) who present with a 0 or low calcium score (CS) still demonstrate coronary artery disease (CAD) and significant stenosis. The... Show moreA considerable number of patients with an acute coronary syndrome (ACS) who present with a 0 or low calcium score (CS) still demonstrate coronary artery disease (CAD) and significant stenosis. The aim of the present study was to evaluate the relation between the CS and the degree and character of atherosclerosis in patients with suspected ACS versus patients with stable CAD obtained by computed tomography angiography and virtual histology intravascular ultrasound (VH IVUS). Overall 112 patients were studied, 53 with ACS and 59 with stable CAD. Calcium scoring and computed tomography angiography were performed and followed by VH IVUS. On computed tomography angiography each segment was evaluated for plaque and classified as noncalcified, mixed, or calcified. Vulnerable plaque characteristics on VH IVUS were defined by percent necrotic core and presence of thin-cap fibroatheroma. If the CS was 0, patients with ACS had a higher mean number of plaques (5.0 +/- 2.0 vs 2.0 +/- 1.9, p <0.05) and noncalcified plaques (4.6 +/- 3.5 vs 1.3 +/- 1.9, p <0.05) on computed tomography angiography than those with stable CAD. If the CS was 0, VH IVUS demonstrated that patients with ACS had a larger amount of necrotic core area (0.58 +/- 0.73 vs 0.22 +/- 0.43 mm(2), p <0.05) and a higher mean number of thin-cap fibroatheromas (0.6 +/- 0.7 vs 0.1 +/- 0.3, p <0.05) than patients with stable CAD. In conclusion, even in the presence of a 0 CS, patients with ACS have increased plaque burden and increased vulnerability compared to patients with stable CAD. Therefore, absence of coronary calcification does not exclude the presence of clinically relevant and potentially vulnerable atherosclerotic plaque burden in patients with ACS. (C) 2011 Elsevier Inc. All rights reserved. (Am J Cardiol 2011;108:658-664) Show less
Coronary computed tomographic angiography allows direct evaluation of the vessel wall and thus positive remodeling, which is a marker of vulnerability. The purpose of this study was to assess the... Show moreCoronary computed tomographic angiography allows direct evaluation of the vessel wall and thus positive remodeling, which is a marker of vulnerability. The purpose of this study was to assess the association between positive remodeling on computed tomography angiogram (CTA) and vulnerable plaque characteristics on virtual histologic intravascular ultrasound (VH IVUS) images. Forty-five patients (78% men, 58 +/- 11 years old) underwent computed tomographic angiography followed by VH IVUS. On CIA, the remodeling index was determined for each lesion by a blinded observer using quantitative analysis. Positive remodeling was defined based on a remodeling index >= 1.0. Percent necrotic core and presence of thin-capped fibroatheroma (TCFA) were used as markers for plaque vulnerability on VH IVUS images. Ninety-nine atherosclerotic plaques were evaluated, of which 37 lesions (37.4%) were identified as having positive remodeling on CTA. Higher levels of plaque vulnerability were identified in lesions with positive remodeling compared to lesions without positive remodeling. Percent necrotic core was significantly higher in lesions with positive remodeling (15.7 +/- 7.8%) compared to lesions without this characteristic (10.2 +/- 7.2%, p <0.001). Furthermore, significantly more TCFA lesions were identified in positively remodeled lesions (n = 16, 43.2%) than in lesions without positive remodeling (n = 3, 4.8%, p <0.001). In conclusion, lesions with positive remodeling on CIA are associated with increased levels of plaque vulnerability on VH IVUS images including a higher percent necrotic core and a higher prevalence of TCFA. Thus evaluation of remodeling on CTA may provide a valuable marker for plaque vulnerability. (C) 2011 Elsevier Inc. All rights reserved. (Am J Cardiol 2011;107:1725-1729) Show less
