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Purpose: To perform a meta-analysis to evaluate the accuracy of 16- and 64-section spiral computed tomography (CT) to help assess coronary artery bypass grafts (CABGs)., Materials and Methods: The MEDLINE, Cochrane library, and BioMed Central databases were searched for relevant original articles published up to May 2007. Major criteria for article inclusion were that it (a) used multisection CT as a diagnostic test for the assessment of significant lesions (occlusion or >50% stenosis) of CABG, (b) used a 16- or 64-section scanner, and (c) used coronary angiography as the reference standard. After data extraction, the analysis was performed according to a random-effects model. Between-study statistical heterogeneity was also assessed by using the Cochran Q chi(2) test., Results: Of 158 screened articles, 15 fulfilled all inclusion criteria. Graft assessability (including distal anastomosis) ranged from 78%-100% among all included studies (mean, 92.4%; 90% with 16- and 96% with 64-section CT; P < .001). Statistical heterogeneity was observed for specificity and positive likelihood ratio (LR), justifying the use of the random-effects model. The analysis, pooled from 15 studies (723 patients, 2023 CABGs), provided the following results for the assessment of graft obstruction (occlusion and >50% stenosis): sensitivity, 97.6% (95% confidence interval [CI]: 96%, 98.6%); specificity, 96.7% (95% CI: 95.6%, 97.5%); positive predictive value, 92.7% (95% CI: 90.5%, 94.6%); negative predictive value, 98.9% (95% CI: 98.2%, 99.4%); positive LR, 23.42 (95% CI: 13.69, 40.07); negative LR, 0.045 (95% CI: 0.028, 0.071); and diagnostic odds ratio, 780.32 (95% CI: 379.12, 1606.1)., Conclusion: Multisection CT provided high accuracy for the evaluation of CABG obstruction in assessable conduits, and might be used as a noninvasive tool for the evaluation of suspected graft dysfunction in patients who are at high risk for complications from coronary angiography., ((c) RSNA, 2008.)

Objectives: This study was designed to define the current role of multislice spiral computed tomography (MSCT) for the diagnosis of coronary artery disease (CAD) using a meta-analytic process., Background: Multislice spiral computed tomography has recently been proposed as an alternative to conventional coronary angiography (CA) for the diagnosis of CAD., Methods: Using Medline, we identified 29 studies (2,024 patients) evaluating CAD by means of both MSCT (> or =16 slices) and conventional CA before July 2006. After data extraction the analysis was performed according to a random-effects model., Results: The per-segment analysis pooled the results from 27 studies corresponding to a cumulative number of 22,798 segments. Among unassessable segments, 4.2% were excluded from the analysis and 6.4% were classified at the discretion of the investigators, underscoring the shortcomings of MSCT. With this major limitation, the per-segment sensitivity and specificity were 81% (95% confidence interval [CI] 72% to 89%) and 93% (95% CI 90% to 97%), respectively, with positive and negative likelihood ratios of 21.5 (95% CI 13.1 to 35.5) and 0.11 (95% CI 0.06 to 0.21), respectively, and positive and negative predictive values of 67.8% (95% CI 57.6% to 78.0%) and 96.5% (95% CI 94.7% to 98.3%), respectively. As expected, the per-patient analysis has shown an increased sensitivity of 96% (95% CI 94% to 98%) but a decreased specificity of 74% (95% CI 65% to 84%)., Conclusions: Multislice spiral computed tomography has shortcomings difficult to overcome in daily practice and, at the more clinically relevant per-patient analysis, continues to have moderate specificity in patients with high prevalence of CAD. Studies evaluating the diagnostic performance of the newest generation of MSCT, including patients with low to moderate CAD prevalence, will be critical in establishing the clinical role of this emerging technology as an alternative to CA.

Background: Surveillance conventional coronary angiography (CCA) is recommended 2 to 6 months after stent-supported left main coronary artery (LMCA) percutaneous coronary intervention due to the unpredictable occurrence of in-stent restenosis (ISR), with its attendant risks. Multislice computed tomography (MSCT) is a promising technique for noninvasive coronary evaluation. We evaluated the diagnostic performance of high-resolution MSCT to detect ISR after stenting of the LMCA., Methods and Results: Seventy-four patients were prospectively identified from a consecutive patient population scheduled for follow-up CCA after LMCA stenting and underwent MSCT before CCA. Until August 2004, a 16-slice scanner was used (n = 27), but we switched to the 64-slice scanner after that period (n = 43). Patients with initial heart rates > 65 bpm received beta-blockers, which resulted in a mean periscan heart rate of 57 +/- 7 bpm. Among patients with technically adequate scans (n = 70), MSCT correctly identified all patients with ISR (10 of 70) but misclassified 5 patients without ISR (false-positives). Overall, the accuracy of MSCT for detection of angiographic ISR was 93%. The sensitivity, specificity, and positive and negative predictive values were 100%, 91%, 67%, and 100%, respectively. When analysis was restricted to patients with stenting of the LMCA with or without extension into a single major side branch, accuracy was 98%. When both branches of the LMCA bifurcation were stented, accuracy was 83%. For the assessment of stent diameter and area, MSCT showed good correlation with intravascular ultrasound (r = 0.78 and 0.73, respectively). An intravascular ultrasound threshold value > or = 1 mm was identified to reliably detect in-stent neointima hyperplasia with MSCT., Conclusions: Current MSCT technology, in combination with optimal heart rate control, allows reliable noninvasive evaluation of selected patients after LMCA stenting. MSCT is safe to exclude left main ISR and may therefore be an acceptable first-line alternative to CCA.

Multislice computed tomography (CT) is an emerging technique for the non-invasive detection of coronary stenoses. While the diagnostic accuracy of 4-slice scanners was limited, 16-slice CT imagers showed promising results due to increased temporal and spatial resolution. These technical advances prompted us to evaluate the diagnostic performance of 64-slice CT coronary angiography in the detection of significant stenoses (defined as > or = 50% luminal diameter reduction) versus invasive quantitative coronary angiography (QCA). Thirty-five patients with stable angina pectoris underwent CT coronary angiography performed with a 64-slice scanner (gantry rotation time 330 ms, individual detector width 0.6 mm) prior to conventional coronary angiography. Patients with heart rates >70 beats/min received 100 mg metoprolol orally. One hundred millilitres of contrast agent with an iodine concentration of 400 mgl/ml were injected at a rate of 5 ml/s into the antecubital vein. The CT scan was triggered with the bolus tracking technique. The sensitivity, specificity and the positive and negative predictive values of 64-slice CT were 99%, 96%, 78% and 99%, respectively, on a per-segment basis. The values obtained on a per-patient basis were 100%, 90%, 96% and 100%, respectively. When referral to catheterisation is questionable, CT coronary angiography may identify subjects with normal angiograms and consistently decrease the number of unnecessary invasive procedures.

The introduction of multislice computed tomography (MSCT) has allowed non-invasive coronary angiography. Although widely applied, extensive information on technical details of the technique is lacking. This survey offers detailed information on patient preparation, data acquisition, reconstruction and interpretation. In addition, a summary of the available studies using MSCT for non-invasive angiography is provided. Based on pooled analysis of direct comparisons between MSCT and invasive angiography, the weighted mean sensitivity and specificity of current 16-slice MSCT for the detection of coronary artery disease are 88% and 96%, respectively. At present, the technique is particularly well suited for reliable exclusion of coronary artery disease. It is important to emphasise that MSCT only provides anatomical images, visualising the presence of atherosclerosis; information on the haemodynamic significance of these lesions (i.e. ischaemia) cannot be derived.