Background: Previous studies have evaluated coronary artery in-stent diameter restenosis(ISDR) using the 64-slice multi-detector computed tomography coronary angiography(MDCT-CA) compared to invasive coronary angiography(ICA) as the gold standard. In our study, we aimed to compare the diagnostic precision of new generation dual source MDCT-CA and ICA with add on intravascular ultrasonography to evaluate ISDR.
Methods: One hundred patients with previously stented coronaries(n=110 stents) underwent MDCT-CA followed by ICA and IVUS within 24 hours. Specificities, Sensitivities, negative predictive values(NPV) and positive predictive values(PPV) of MDCT-CA and ICA for confirming or excluding ISDR by measuring in-stent area restenosis(ISAR) and minimal luminal area(MLA) ≤4.0 mm2 of IVUS was taken as the standard reference standard.
Results: Newer generation dual source MDCT-CA and IVUS had a good sensitivity, specificity and accuracy in detection of ISDR. However, the patients have to be carefully selected. Consistent with previous MDCT-CA studies, our study observed significant effect of stent diameter on assessability, with 3 mm being a cutoff point below which the percentage of assessable stents is extremely low. When using IVUS MLA of 4.0 mm2 as a reference method for identification of ISDR, no significant difference was detected between MDCT-CA and ICA in identification of ISDR.The higher NPV of MDCT-CA when compared with ICA and IVUS(100% and 100% respectively),therefore,MDCT-CA had an important role in exclusion of ISDR.
Conclusions: In conclusion,when evaluating the patency of stents,newer generation dual source MDCT-CA has the same performance as coronary angiography and IVUS and has the following advantages:non-invasiveness,low cost,and easy and convenient operation.