Coronary Stent Fracture: Detection with 64-Section Multidetector CT Angiography in Patients and in Vitro

Abstract

To evaluate 64-section multidetector coronary computed tomographic (CT) angiography for the depiction of coronary stent fracture in patients and in vitro. This retrospective study was approved by the institutional review board, and informed patient consent was waived. The coronary CT angiograms obtained in 371 consecutive patients (268 men, 103 women; mean age, 62.9 years) with 545 stents were reviewed. All patients with stent fractures underwent conventional coronary angiography and/or fluoroscopy as part of their medical care. In phantom studies, magnified radiographs of three types of drug-eluting stents in their fully expanded, maximally bent, and unrolled states were obtained. CT angiography and fluoroscopy of a water phantom that contained two drug-eluting stents--Cypher and Taxus devices--with four fractures each were performed, and two radiologists blinded to the fracture information evaluated the images. Twenty-four stents with fractures were identified. Eighteen fractured stents (13 Cypher, four Taxus, one S670) in 14 patients were detected with CT angiography; six (33%; two Cypher, four Taxus) of these 18 stents in five (36%) patients were not detected on conventional angiograms at the initial readings. Six fractured stents showed significant (>50%) recurrent in-stent stenosis. Of 58 arteries with overlapping stent placements, eight (14%) had fractures involving 11 stents. In the in vitro studies, 57 stent fractures (31 Cypher, 26 Taxus) were detected with CT angiography and 38 (18 Cypher, 20 Taxus) were detected with fluoroscopy. Coronary CT angiography depicts stent fractures in patients and phantoms, even those fractures that are not clearly depicted by conventional angiography. http://radiology.rsnajnls.org/cgi/content/full/249/3/810/DC1.