ABSTRACT
<p><b>BACKGROUND</b>The durable presence of polymer coating on drug-eluting stent (DES) surface may be one of the principal reasons for stent thrombosis. The long-term coronary arterial response to biodegradable polymer-coated sirolimus-eluting stent (BSES) in vivo remained unclear.</p><p><b>METHODS</b>Forty-one patients were enrolled in this study and virtual histology intravascular ultrasound (VH-IVUS) was performed to assess the native artery vascular responses to BSES compared with durable polymer-coated SES (DSES) during long-term follow-up (median: 8 months). The incidence of necrotic core abutting to the lumen was evaluated at follow-up.</p><p><b>RESULTS</b>With similar in-stent late luminal loss (0.15 mm (0.06-0.30 mm) vs. 0.19 mm (0.03-0.30 mm), P = 0.772), the overall incidence of necrotic core abutting to the lumen was significantly less in BSES group than in DSES group (44% vs. 63%, P < 0.05) (proximal 18%, stented site 14% and distal 12% in BSES group, proximal 19%, stented site 28% and distal 16% in DSES group). The DSES-treated segments had a significant higher incidence of necrotic core abutting to the lumen through the stent struts (73% vs. 36%, P < 0.01). In addition, more multiple necrotic core abutting to the lumen was observed in DSES group (overall: 63% vs. 36%, P < 0.05). Furthermore, when the stented segments with necrotic core abutting to the lumen had been taken into account only, DSES-treated lesions tended to contain more multiple necrotic core abutting to the lumen through the stent struts than BSES-treated lesions (74% vs. 33%), although there was no statistically significant difference between them (P = 0.06).</p><p><b>CONCLUSIONS</b>By VH-IVUS analysis at follow-up, a greater frequency of stable lesion morphometry was shown in lesions treated with BSESs compared with lesions treated with DSESs. The major reason was BSES produced less toxicity to the arterial wall and facilitated neointimal healing as a result of polymer coating on DES surface biodegraded as time went by.</p>
Subject(s)
Female , Humans , Male , Middle Aged , Coronary Angiography , Coronary Artery Disease , Diagnostic Imaging , Therapeutics , Coronary Vessels , Diagnostic Imaging , Drug-Eluting Stents , Sirolimus , Therapeutic Uses , UltrasonographyABSTRACT
<p><b>BACKGROUND</b>Unheralded sudden death and acute myocardial infarction are common manifestations of coronary atherosclerosis. Such events are related to thrombotic occlusion at the site of non-flow limiting atherosclerotic plaques in epicardial coronary arteries. This study aimed to assess plaque characterization of nonculprit lesions in patients with acute coronary syndrome (ACS) compared with those with stable angina pectoris (SAP) determined by analysis of intravascular ultrasound (IVUS) radiofrequency (RF) data.</p><p><b>METHODS</b>In 81 patients, nonculprit vessels with < 50% diameter stenosis and nontarget segment of culprit vessels with < 50% diameter stenosis were studied with IVUS. Tissue maps were reconstructed from RF data using IVUS-Virtual Histology software.</p><p><b>RESULTS</b>Mean lipid core percentage was significantly higher in patients with ACS than in those with SAP ((25.78 +/- 6.30)% vs (9.11 +/- 4.90)%, P < 0.001). In addition, patients with SAP showed more fibrotic vessels ((59.66 +/- 16.87)% vs (49.07 +/- 10.20)%, P < 0.001). There was no significant difference in either mean calcium ((4.37 +/- 2.40)% vs (5.12 +/- 3.00)%, P = 0.225) or fibrolipid ((24.94 +/- 9.40)% vs (25.82 +/- 13.60)%, P = 0.731) percentages in nonculprit vessels, but the mean calcium percentage was significantly higher in nontarget lesions of culprit vessels ((5.51 +/- 3.29)% vs (3.57 +/- 2.10)%, P = 0.003). In addition, there was a positive correlation between lipid core and remodeling index (RI) (r = 0.847, P < 0.001) and a negative correlation between fibrous tissue and RI (r = -0.946, P < 0.001).</p><p><b>CONCLUSIONS</b>In this study, in both nonculprit vessels and nontarget lesion of culprit vessels, plaque characterization of nonculprit lesions determined by spectral analysis of IVUS RF data was significantly different in patients with ACS. The percentage of lipid core was significantly higher in patients with ACS than in those with SAP. Conversely, SAP patients showed more fibrotic content. In vivo plaque composition and morphological changes were related to remodeling of the coronary artery tree.</p>