Different value of coronary calcium score to predict obstructive coronary artery disease in patients with and without moderate chronic kidney disease.

PURPOSE: The coronary calcium score (CCS) predicts significant coronary artery disease (CAD) in the general population. While moderate chronic kidney disease (CKD) is associated with high CCS, the use of CCS to predict significant CAD in these patients is unknown. METHODS: A total of 704 patients underwent computed tomography coronary angiography for the assessment of CCS and CAD. Sixty-nine (10 %) patients had moderate CKD, defined by an estimated glomerular filtration rate (eGFR) between 30 and 59 mL/min/1.73m(2), and the remaining patients were considered to be without significant CKD (eGFR ≥ 60 mL/min/1.73m(2)). RESULTS: Patients with moderate CKD were older, had a higher CCS, and a higher prevalence of obstructive CAD than patients without significant CKD. Receiver-operator curve analysis showed that CCS predicted the presence of obstructive CAD in both patients with moderate CKD and those without significant CKD. In patients with moderate CKD, the optimal cut-off value of CCS to diagnose obstructive CAD was 140 (sensitivity 73 % and specificity of 70 %), and is 2.8 fold higher than in patients without significant CKD (cut-off value = 50; sensitivity 75 % and specificity 75 %). CONCLUSION: The present results demonstrate that CCS can predict obstructive CAD in patients with moderate CKD, although the optimal cut-off value is higher than in patients without significant CKD.

Clinical application of CT coronary angiography: state of the art.

In recent years, multi-slice computed tomography (MSCT) technology has developed rapidly, allowing high-resolution non-invasive imaging of the coronary arteries and surrounding structures. Since the introduction of MSCT, acquisition time, detector number, spatial and temporal resolution have continuously improved with each new scanner generation, resulting in excellent image quality and diagnostic accuracy in the detection of coronary artery disease (CAD). At the same time, developments in MSCT technology have focused on reduction of the radiation dose. In particular, the availability of dose modulation and prospective ECG gating have drastically reduced patient radiation dose. Moreover, with the introduction of 320-slice MSCT, volumetric scanning of the entire heart has become possible in a single heart beat or gantry rotation, thereby eliminating oversampling and stair-step artifact. The present article provides an overview of state of the art clinical applications of cardiac MSCT, including the diagnosis of CAD, evaluation of plaque morphology and composition, prognostification, and the evaluation of left ventricular function and aortic and mitral valve anatomy.

Performance and efficacy of 320-row computed tomography coronary angiography in patients presenting with acute chest pain: results from a clinical registry.

The purpose of this study was to evaluate the performance of 320-row computed tomography angiography (CTA) in the identification of significant coronary artery disease (CAD) in patients presenting with acute chest pain and to examine the relation to outcome during follow-up. A total of 106 patients with acute chest pain underwent CTA to evaluate presence of CAD. Each CTA was classified as: normal, non-significant CAD (<50% luminal narrowing) and significant CAD (≥50% luminal narrowing). CTA results were compared with quantitative coronary angiography. After discharge, the following cardiovascular events were recorded: cardiac death, non-fatal infarction, and unstable angina requiring revascularization. Among the 106 patients, 23 patients (22%) had a normal CTA, 19 patients (18%) had non-significant CAD on CTA, 59 patients (55%) had significant CAD on CTA, and 5 patients (5%) had non-diagnostic image quality. In total, 16 patients (15%) were immediately discharged after normal CTA and 90 patients (85%) underwent invasive coronary angiography. Sensitivity, specificity, and positive and negative predictive values to detect significant CAD on CTA were 100, 87, 93, and 100%, respectively. During mean follow-up of 13.7 months, no cardiovascular events occurred in patients with a normal CTA examination. In patients with non-significant CAD on CTA, no cardiac death or myocardial infarctions occurred and only 1 patient underwent revascularization due to unstable angina. In patients presenting with acute chest pain, an excellent clinical performance for the non-invasive assessment of significant CAD was demonstrated using CTA. Importantly, normal or non-significant CAD on CTA predicted a low rate of adverse cardiovascular events and favorable outcome during follow-up.

Non-invasive assessment of atherosclerotic coronary lesion length using multidetector computed tomography angiography: comparison to quantitative coronary angiography.

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 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.

Plaque type and composition as evaluated non-invasively by MSCT angiography and invasively by VH IVUS in relation to the degree of stenosis.

BACKGROUND: Imaging of coronary plaques has traditionally focused on evaluating degree of stenosis, as the risk for adverse cardiac events increases with stenosis severity. However, the relation between plaque composition and severity of stenosis remains largely unknown. OBJECTIVE: To assess plaque composition (non-invasively by multislice computed tomography (MSCT) angiography and invasively by virtual histology intravascular ultrasound (VH IVUS)) in relation to degree of stenosis. METHODS: 78 patients underwent MSCT (identifying three plaque types; non-calcified, calcified, mixed) followed by invasive coronary angiography and VH IVUS. VH IVUS evaluated plaque burden, minimal lumen area and plaque composition (fibrotic, fibro-fatty, necrotic core, dense calcium) and plaques were classified as fibrocalcific, fibroatheroma, thin-capped fibroatheroma (TCFA), pathological intimal thickening. For each plaque, percentage stenosis was evaluated by quantitative coronary angiography. Significant stenosis was defined >50% stenosis. RESULTS: Overall, 43 plaques (19%) corresponded to significant stenosis. Of the 227 plaques analysed, 70 were non-calcified plaques (31%), 96 mixed (42%) and 61 calcified (27%) on MSCT. Plaque types on MSCT were equally distributed among significant and non-significant stenoses. VH IVUS identified that plaques with significant stenosis had higher plaque burden (67% (11%) vs 53% (12%), p<0.05) and smaller minimal lumen area (4.6 (3.8-6.8) mm(2) vs 7.3 (5.4-10.5) mm(2), p<0.05). Interestingly, no differences were observed in percentage fibrotic, fibro-fatty, necrotic core and dense calcium. Non-significant stenoses were more frequently classified as pathological intimal thickening (46 (25%) vs 3 (7%), p<0.05), although TCFA (more vulnerable plaque) was distributed equally (p = 0.18). CONCLUSION: No evident association exists between the degree of stenosis and plaque composition or vulnerability, as evaluated non-invasively by MSCT and invasively by VH IVUS.