Usefulness of 64-slice multislice computed tomography coronary angiography to assess in-stent restenosis.

OBJECTIVES: This study sought to evaluate the diagnostic accuracy of 64-slice multislice computed tomography (MSCT) coronary angiography in the follow-up of patients with previous coronary stent implantation. BACKGROUND: Recent investigations have shown increased image quality and diagnostic accuracy for noninvasive coronary angiography with 64-slice MSCT as compared with previous-generation MSCT scanners, but data on the evaluation of coronary stents are scarce. METHODS: In 182 patients (152 [84%] male, ages 58 +/- 11 years) with previous stent (> or =2.5 mm diameter) implantation (n = 192), 64-slice MSCT angiography using either a Sensation 64 (Siemens, Forchheim, Germany) or Aquilion 64 (Toshiba, Otawara, Japan) was performed. At each center, coronary stents were evaluated by 2 experienced observers and evaluated for the presence of significant (> or =50%) in-stent restenosis. Quantitative coronary angiography served as the standard of reference. RESULTS: A total of 14 (7.3%) stented segments were excluded because of poor image quality. In the interpretable stents, 20 of the 178 (11.2%) evaluated stents were significantly diseased, of which 19 were correctly detected by 64-slice MSCT. Accordingly, sensitivity, specificity, and positive and negative predictive value to identify in-stent restenosis in interpretable stents were 95.0% (95% confidence interval [CI] 85% to 100%), 93.0% (95% CI 90% to 97%), 63.3% (95% CI 46% to 81%), and 99.3% (95% CI 98% to 100%), respectively. CONCLUSIONS: In-stent restenosis can be evaluated with 64-slice MSCT with good diagnostic accuracy. In particular, a high negative predictive value of 99% was observed, indicating that 64-slice MSCT may be most valuable as a noninvasive method of excluding in-stent restenosis.     

Diagnosis of coronary in-stent restenosis with multidetector row spiral computed tomography.

OBJECTIVES: The purpose of this study was to assess the accuracy of a new generation spiral multidetector computed tomography (MDCT) scanner (Brilliance 40, Philips Medical Systems, Cleveland, Ohio) in the diagnosis of coronary in-stent restenosis (ISR). BACKGROUND: Noninvasive imaging of ISR would be clinically useful, but artifacts caused by metallic stent struts have limited the role of early generation MDCT scanners. METHODS: We examined 65 patients (age 63 +/- 12 years, 48 [73.8%] men) with 111 implanted coronary stents who were referred for repeat invasive coronary angiography (ICA). Patients underwent 40-slice MDCT one to three days before scheduled ICA, using intravenous contrast enhancement. Images were reconstructed in multiple formats using retrospective electrocardiographic gating. Stents were viewed in their long and short axes and luminal contrast attenuation graded from MDCT grade 1 (minimal restenosis) to 4 (severe restenosis) by consensus of two observers. RESULTS: In-stent restenosis (>/=60% luminal narrowing by quantitative coronary angiography) was found on ICA in 18 (16.2%) of the stented segments and in 16 (24.6%) patients. The MDCT findings correlated with ICA restenosis, with restenosis in only 1 of 59 (1.6%) MDCT grade 1 segments, but in more than three-quarters (12 of 15, 80%) of MDCT grade 4 segments (sensitivity 72.2%, specificity 92.5%, positive predictive value [PPV] 65.0%, negative predictive value [NPV] 94.5% [five stents not assessable by MDCT considered as restenosis]). Using MDCT grades 3 or 4 combined for restenosis, sensitivity of MDCT was 88.9%, specificity 80.6%, PPV 47.1%, and NPV 97.4%. CONCLUSIONS: In-stent restenosis can be diagnosed with moderate sensitivity using a new generation 40-slice MDCT scanner. The high NPV implies a significant role for MDCT in excluding ISR.     

Detection of plaque rupture using 64-slice multidetector row computed tomography

The present case report describes a 37-year-old man who presented to the emergency room with symptoms of a myocardial infarction but no high-grade stenosis on conventional catheter angiography. Consecutive multidetector row computed tomography of the coronary arteries showed an intimal flap along a fibrous plaque formation in the left anterior descending artery. This finding was found to represent a plaque rupture, and the lesion was treated with an 18 mm stent. Multidetector row computed tomography helped to correctly position the stent by identifying the exact location of the rupture along the long plaque formation.     

Usefulness of 64-detector row computed tomography for evaluation of intracoronary stents in symptomatic patients with suspected in-stent restenosis

To determine whether 64-slice multidetector computed tomographic coronary angiography (MDCTA) can accurately assess the coronary artery lumen in symptomatic patients with previous coronary artery stents and potential in-stent restenosis (ISR). The primary aim was to determine the accuracy of binary ISR exclusion using MDCTA compared with invasive catheter angiography (ICA). Secondary aims were comparisons of stent dimensions measured using MDCTA and variables that affect accuracy. Forty patients with previous stent placement underwent both ICA and 64-slice MDCTA after elective presentation with chest pain, and ICA quantitative coronary angiographic data were used as the reference standard. Thirty-six men and 4 women (age 64 +/- 10 years; range 44 to 83) with 103 stents (2.8 +/- 1.6 stents/patient) were comparatively evaluated (stent exclusion rate 9.6%). There were 45 bare-metal and 58 drug-eluting stents (20 +/- 18 months after implantation) with an average diameter of 3.23 +/- 0.7 mm. Overall accuracy for the detection of significant ISR showed sensitivity, specificity, and positive and negative predictive values of 85%, 86%, 61%, and 96% for proximal stents > or =3 mm, which improved to 100%, 94%, 81%, and 100%; if the visible luminal diameter on MDCTA was <1.5 mm, accuracy decreased to 40%, 84%, 29%, and 90%, respectively. In conclusion, 64-slice MDCTA assessment of symptomatic patients with suspected clinically significant ISR is a realistic alternative to ICA if reference stent diameter is > or =2.5 mm and visible lumen cross-sectional diameter is > or =1.5 mm, for which a negative MDCTA result virtually excludes the presence of significant ISR.     

Diagnostic accuracy of coronary in-stent restenosis using 64-slice computed tomography: comparison with invasive coronary angiography.

OBJECTIVES: This study sought to evaluate the diagnostic accuracy of coronary binary in-stent restenosis (ISR) with angiography using 64-slice multislice computed tomography coronary angiography (CTCA) compared with invasive coronary angiography (ICA). BACKGROUND: A noninvasive detection of ISR would result in an easier and safer way to conduct patient follow-up. METHODS: We performed CTCA in 81 patients after stent implantation, and 125 stented lesions were scanned. Two sets of images were reconstructed with different types of convolution kernels. On CTCA, neointimal proliferation was visually evaluated according to luminal contrast attenuation inside the stent. Lesions were graded as follows: grade 1, none or slight neointimal proliferation; grade 2, neointimal proliferation with no significant stenosis (<50%); grade 3, neointimal proliferation with moderate stenosis (> or =50%); and grade 4, neointimal proliferation with severe stenosis (> or =75%). Grades 3 and 4 were considered binary ISR. The diagnostic accuracy of CTCA compared with ICA was evaluated. RESULTS: By ICA, 24 ISRs were diagnosed. Sensitivity, specificity, positive predictive value, and negative predictive value were 92%, 81%, 54%, and 98% for the overall population, whereas values were 91%, 93%, 77%, and 98% when excluding unassessable segments (15 segments, 12%). For assessable segments, CTCA correctly diagnosed 20 of the 22 ISRs detected by ICA. Six lesions without ISR were overestimated as ISR by CTCA. As the grade of neointimal proliferation by CTCA increases, the median value of percent diameter stenosis increased linearly. CONCLUSIONS: Binary ISR can be excluded with high probability by CTCA, with a moderate rate of false-positive results.     

Usefulness of 64-detector computed tomographic angiography for diagnosing in-stent restenosis in native coronary arteries

The purpose of this study was to evaluate the accuracy of detector computed tomographic angiographic qualitative and quantitative analyses for the detection of in-stent restenosis (ISR) Previous studies have used qualitative analyses exclusively and have excluded "unevaluable" stents. Multidetector computed tomographic angiography (MDCT) was performed before quantitative coronary angiography in 67 patients with 132 stents that were evaluated by 2 techniques: (1) qualitative, on the basis of degree of visual hypodensity, and (2) quantitative, comparing in-stent with prestent Hounsfield units. All stents were evaluated, irrespective of image quality. The incidence of ISR was 12.5%. The sensitivity (94%), specificity (74%), and positive predictive value (39%) of the qualitative evaluation were superior to the quantitative technique (82%, 54%, and 21%, respectively); negative predictive values were similar (99% vs 95%). Accuracies were equal in stents located in proximal and distal vessels. In conclusion, ISR can be evaluated qualitatively by 64-slice MDCT with excellent sensitivity and negative predictive accuracy without exclusion of unevaluable stents and with reasonable specificity but low positive predictive value. Quantitative analysis was less accurate.     

Evaluation of pulmonary atresia with 64-slice multidetector computed tomography (MDCT)

Pulmonary atresia with ventricular septal defect is a complex congenital heart disease. We report a case of a 46-year-old woman with pulmonary atresia and ventricular septal defect, surgically treated when she was 15 years old with an implant of a conduit between ascending aorta and left pulmonary branch. A 64-slice computed tomography was performed to assess the conduit patency. The contrast enhanced MDCT study showed the conduit was pervious and correctly connected with an enlarged left pulmonary artery implant of a conduit between ascending aorta and left pulmonary branch.     

双源CT在冠状动脉支架内再狭窄诊断中的价值

目的 参照定量冠状动脉造影结果,评价双源CT在冠状动脉支架内再狭窄诊断中的价值.方法 对55例支架术后出现胸闷、胸痛的冠心病患者,在术后6～12个月行双源CT检查及定量冠状动脉造影.以定量冠状动脉造影结果为参照,评价双源CT诊断支架内再狭窄的真阳性、真阴性、假阳性、假阴性,并计算敏感性、特异性、阳性预测值、阴性预测值.分析心率、置人支架情况对双源CT诊断性能的影响.结果 55例患者共置入89枚支架,其中31.5%(28/89)的支架经冠状动脉造影证实发生支架内再狭窄.双源CT诊断支架内再狭窄的敏感性、特异性、阳性预测值、阴性预测值分别为89%、87%、76%和95%.双源CT诊断心率＜70次/min及≥70次/min患者支架内再狭窄的敏感性(94%比82%)、特异性(88%比90%)、阳性预测值(76%比75%)、阴性预测值(97%比93%)差异无统计学意义(P＞0.05).双源CT诊断重叠支架、分叉部位支架与单支架再狭窄的敏感性(84%比100%)、特异性(81%比96%)、阳性预测值(70%比90%)和阴性预测值(91%比100%)差异无统计学意义(P＞0.05).双源CT诊断直径≥3.50 mm支架、直径3.00 mm支架和直径≤2.75mm支架发生再狭窄的特异性(分别为100%、80%和66%,P＜0.05)和阳性预测值(分别为100%、95%和53%,P＜0.05)差异有统计学意义.结论 双源CT对大直径支架的再狭窄有较好的诊断性能,且不受心率和支架分布情况的影响.

Abstract：

Objective To evaluate the value of dual source computed tomography coronary angiography(DSCT-CA)on detecting in-stent restenosis(＞ 50% luminal narrowing)in symptomatic patients referred for quantitative coronary angiography(QAC). Methods Fifty five patients(43 males)with chest pain after coronary stent implantation within 6 - 12 months were evaluated by DSCT-CA and QAC. The sensitivity, specificity, positive predictive value(PPV)and negative predictive value(NPV)of DSCT-CA were calculated using coronary angiography as gold standard. Results Eighty nine stents were implanted.In-stent restenosis was evidenced in 28 stents(31.5%)by QAC. The sensitivity, specificity PPV and NPV of DSCT-CA for the diagnosis of in-stent restenosis was 89%, 87%, 76% and 95%, respectively.Diagnostic efficiency was not affected by heart rate and the sensitivity was 0. 94 vs. 0.82, the specificity 0. 88 vs. 0. 90, the PPV 0. 76 vs. 0.75 and the NPV 0. 97 vs. 0. 93(all P ＞ 0. 05)between patients with heart rate ＜70 beats/min and patients with heart rate≥70 beats/min. The sensitivity(84% vs. 100%),specificity(81% vs. 96%), PPV(70% vs. 90%)and NPV(91% vs. 100%)were similar between overlapping or bifurcations stents and single stents. The specificity(100% vs. 80% vs. 66%)and PPV (100% vs. 95% vs. 53%)were significantly higher in the groups with stents ≥3.50 mm, stents 3.00 mm than in stents ≤2. 75 mm(both P ＜ 0. 05). Conclusion Diagnostic efficiency of in-stent restenosis with DSCT-CA in the large diameter stent is better than in the small diameter stent and the diagnosis efficacy is not affected by heart rate and stent distribution.     

Assessment of coronary artery stent restenosis by 64-slice multi-detector computed tomography.

AIMS: We investigated the feasibility of assessing coronary artery stent restenosis using a new generation 64-slice multi-detector computed tomography-scanner (MDCT) in comparison to conventional quantitative angiography. METHODS AND RESULTS: MDCT was performed in 64 consecutive patients (mean age 58+/-10 years) with previously implanted coronary artery stents (102 stented lesions: mean stent diameter 3.17+/-0.38 mm). Each stent was classified as 'evaluable' or 'unevaluable', and in evaluable stents, the presence of in-stent restenosis (diameter reduction >50%) was determined visually. Results were verified against invasive, quantitative coronary angiography. Fifty-nine stented lesions (58%) were classified as evaluable in MDCT. The mean diameter of evaluable stents was 3.28+/-0.40 mm, whereas the mean diameter of non-evaluable stents was 3.03+/-0.31 mm (P=0.0002). Overall, six of 12 in-stent restenoses were correctly detected by MDCT [50% sensitivity (confidence interval 22-77%)] and in 51 of 90 lesions, in-stent restenosis was correctly ruled out [57% specificity (46-67%)]. In evaluable stents, six of seven in-stent restenoses were correctly detected, and the absence of in-stent stenosis was correctly identified in 51 of 52 cases [sensitivity 86% (42-99%) and specificity 98% (88-100%)]. CONCLUSION: Stent type and diameter influence evaluability concerning in-stent restenosis by MDCT. The rate of assessable stents is low, but in evaluable stents, accuracy for detection of in-stent restenosis can be high.