ABSTRACT
INTRODUCTION: The aim of this prospective study was to evaluate the diagnostic accuracy of dual-source computed tomography coronary angiography (CTCA) compared to intravascular ultrasound (IVUS) for the detection of restenosis in patients who underwent coronary stenting for bifurcation left main (LM) stenosis. MATERIAL AND METHODS: Twenty-four patients underwent percutaneous intervention of the LM and were subsequently examined (median 9.2 months after procedure) using IVUS and CTCA for the detection of restenosis. RESULTS: Significant restenosis was detected according to IVUS examination in 6 patients (25%) and 8 segments (13%). Based on segment analysis, sensitivity, specificity, positive and negative predictive values of CTCA for the detection of restenosis were 89%, 68%, 32%, 97%, respectively. There was moderate to good correlation between the minimal luminal area (MLA), measured by CTCA and IVUS for LM, the left anterior descending artery (LAD) and the left circumflex artery (LCx) (r=0.64, p<0.01; r=0.49, p=0.03; r=0.76, p<0.01, respectively). A Bland-Altman analysis showed that the MLAs measured by CTCA were underestimated in all segments (mean difference 1.67 ±2.2 mm(2) for LM; 2.0 ±2.0 mm(2) for LAD; 1.79 ±1.79 mm(2) for LCx). An ROC analysis of the MLAs derived by CTCA for detecting significant stenosis was performed. The area under the curve for all analysed segments was 0.73. CONCLUSIONS: The present study demonstrates that in patients after LM bifurcation stenting CTCA performs well in the exclusion of in-segment restenosis. However, due to the low positive predictive value of CTCA, the finding of any restenosis should be confirmed by invasive examination.
ABSTRACT
OBJECTIVES: The aim of this study was to evaluate the diagnostic accuracy of dual-source computed tomography coronary angiography (CTCA) compared to coronary angiography (CAG) and intravascular ultrasound (IVUS) for detection and quantification of in-stent restenosis after left main (LM) coronary artery stenting. MATERIALS AND METHODS: Fifty-one patients with percutaneous coronary intervention of the LM were prospectively evaluated. Thirty-four of them underwent 56 complete follow-up examinations (CTCA, CAG, and IVUS as gold standard examination) that focused on detection and quantification of restenosis. RESULTS: Sensitivity, specificity, and positive and negative predictive values were 100%, 94%, 50%, and 100% for CAG, respectively, and 100%, 74%, 18%, and 100% for CTCA, respectively. There was a correlation between the minimal luminal areas (MLA) measured by CTCA and IVUS (r = 0.63; P<.01). A Bland-Altman analysis showed that the MLA measured by CTCA was underestimated (mean difference, 2.14 ± 2.24 mm²). CONCLUSION: Dual-source CTCA has a high negative predictive value and might be considered a less invasive alternative to CAG for exclusion of LM in-stent restenosis. However, there was only a moderate correlation between the MLA measurements by IVUS and CTCA in the stented LMs. Moreover, the present results suggest a systematic underestimation of MLAs measured by CTCA. Therefore, finding of any restenosis according to CTCA should be re-evaluated by CAG or, better, by subsequent IVUS.
