Is this atherosclerosis in patients with HIV? Data received by OCT

Background Chronic infection by HIV evolves with a vascular inflammatory action causing endothelial dysfunction. The action of the virus as well as the side effects of antiretroviral drugs contributes to the progression of cardiovascular diseases. The study aimed to characterise the changes of the structure of the coronary wall and the thickening of the intima by Optical Coherence Tomography in HIV-infected patients with or without symptoms of coronary heart disease. Methods Fifty-two HIV-infected individuals had a mean age of 49.8±11.4 years. There were 75% men, diabetes 30,8%, hypertension 30,8%, smokers 34,62% and 7,7% with cholesterol levels ≥99 mg/dl. Control group included 120 non-HIV-infected controls with coronary heart disease. All the participants from HIV-group receive ART, 100% of participants had plasma HIV RNA <20 copies/mL and 78,85% of them have symptoms of coronary artery disease. Results The average diffuse homogeneous thickening of the intima in patients with HIV was 0.67±0.24 mm, and 0.34±0.18 mm in control group, with normal values not exceeding 0.05 mm. There was impaired three-layer structure of coronary wall in 90,4% (47 of 52) HIV-infected participants and in 60% of control group, atherosclerotic plaque had only 34,62% of HIV group. All HIV-infected patients receive ART more than 5 years. Conclusion The coronary angiography and OCT demonstratedthat the inflammatory process resulting from HIV-infection or HAART may be relevant in the changes of coronary arteries in HIV-positive patients. The changes are predominantly represented by thickening of the intima, impaired three-layer structure of arterial wall and accelerating atherosclerosis. FUNDunding Acknowledgement Type of funding sources: Public Institution(s). Main funding source(s): Russian National Research Medical University named after N.I. PirogovCentral Clinical Hospital of Russian Academy of Science, Moscow, Russia

Follow up coronary vessel evaluation of magnesium bioresorbable stents with coronary computed tomography angiography

Background Cardiac computed tomography angiography (CCTA) has already shown its ability to evaluate late results of polymer-based bioresorbable scaffolds (BVS) in different clinical scenarios. Recently, magnesium-based BVS (Mg-BVS) has emerged as an interesting alternative to these previous platforms due to its lower risk of thrombosis. Nonetheless, there is no systematic data about characterization of magnesium BVS with CCTA. Purpose To study the feasibility of Mg-BVS assessment with CCTA and to evaluate in-scaffold wall tissue characterization during the follow-up. Methods In this multicentre work, CCTA was performed in patients with a previously implanted Mg-BVS as a supplementary follow-up assessment. All studies were done after the theoretical resorption time of the scaffolds. A central core laboratory with an independent level 3 expert in CCTA blinded to the clinical and angiographic results analysed the studies. For this purpose, a dedicated software for coronary analysis was used to quantify coronary stenosis and evaluate coronary wall (Figure). Results Eight patients (55±6 years-old; 87.5% male) with a previously implanted Mg-BVS from 3 different centres in Spain and Italy were included. The presentation was equally distributed (2, 25%) among stable and unstable angina, NSTEMI and STEMI. Target vessels included 5 left anterior descending (62.5%), 2 left circumflex (25%) and 1 right coronary arteries (12.5%). CTCA was performed 13 [11.3–20] months after BVS implantation. In spite of the blinding, all scaffolds were accurately located through identification of proximal and distal radiopaque markers. Concordance of CCTA Mg-BVS sizing was good for diameter (ICC 0.66; p=0.09) and excellent for length (ICC 0.98; p<0,001) of the stents. Patency of all scaffolds was confirmed without significant diameter (0.14 [0–0.27]%) or area (0.39 [0.19–0.57]%) stenoses compared with proximal reference segments. Moreover, within the stent boundaries the maximum luminal diameter and area narrowing were 0.22 [0,12–0.3]% and 0.39 [0.23–0.5]% respectively, in keeping with mild in-scaffold late loss and/or underlying plaque growth. Regarding coronary wall tissue characterization of segments with BVS, there was a plaque burden of 0.37 [0.31–0.48]% and plaque volume of 87.6 [50.2–189.3] mm3. The most common component of the plaque was fibrous (69.5 [33.9–133.7]%), suggesting that Mg-BVS allows for stabilization of unstable culprit lesions (6/8 cases). Compared to the proximal and distal reference segments, there was no differences in plaque volume or composition, suggesting a good coronary vessel healing. Conclusions This short series shows for the first time the ability of CCTA to correctly locate and evaluate patency of Mg-BVS. Moreover, the lack of metal struts allows a detailed coronary plaque evaluation at treated segments. These preliminary results suggest plaque stabilization and a good coronary vessel healing with this novel scaffold. FUNDunding Acknowledgement Type of funding sources: None. Mg-BVS in LCx with mixed plaque

Early Atherosclerotic Changes in Coronary Arteries are Associated with Endothelium Shear Stress Contraction/Expansion Variability

Although unphysiological wall shear stress (WSS) has become the consensus hemodynamic mechanism for coronary atherosclerosis, the complex biomechanical stimulus affecting atherosclerosis evolution is still undetermined. This has motivated the interest on the contraction/expansion action exerted by WSS on the endothelium, obtained through the WSS topological skeleton analysis. This study tests the ability of this WSS feature, alone or combined with WSS magnitude, to predict coronary wall thickness (WT) longitudinal changes. Nine coronary arteries of hypercholesterolemic minipigs underwent imaging with local WT measurement at three time points: baseline (T1), after 5.6 ± 0.9 (T2), and 7.6 ± 2.5 (T3) months. Individualized computational hemodynamic simulations were performed at T1 and T2. The variability of the WSS contraction/expansion action along the cardiac cycle was quantified using the WSS topological shear variation index (TSVI). Alone or combined, high TSVI and low WSS significantly co-localized with high WT at the same time points and were significant predictors of thickening at later time points. TSVI and WSS magnitude values in a physiological range appeared to play an atheroprotective role. Both the variability of the WSS contraction/expansion action and WSS magnitude, accounting for different hemodynamic effects on the endothelium, (1) are linked to WT changes and (2) concur to identify WSS features leading to coronary atherosclerosis.

High Coronary Wall Shear Stress Worsens Plaque Vulnerability: A Systematic Review and Meta-Analysis

Aim: The aim of this meta-analysis is to assess the impact of wall shear stress (WSS) severity on arterial plaque vulnerability. Methods: We systematically searched electronic databases and selected studies which assessed the relationship between WSS measured by intravascular ultrasound and coronary artery plaque features. In 7 studies, a total of 615 patients with 28 276 arterial segments (median follow-up: 7.71 months) were identified. At follow-up, the pooled analysis showed high WSS to be associated with regression of plaque fibrous area, weighted mean difference (WMD) −0.11 (95% CI: −0.20 to −0.02, P = .02) and fibrofatty area, WMD −0.09 (95% CI: −0.17 to −0.01, P = .02), reduction in plaque total area, WMD −0.09 (95% CI: −0.14 to −0.04, P = .007) and increased necrotic core area, and WMD 0.04 (95% CI: 0.01-0.09, P = .03) compared with low WSS. Dense calcium deposits remained unchanged in high and low WSS (0.01 vs 0.02 mm2; P > .05). High WSS resulted in profound remodeling (40% vs 18%, P < .05) and with more constructive remodeling than low WSS (78% vs 40%, P < .01). Conclusions: High WSS in coronary arteries is associated with worsening plaque vulnerability and more profound arterial wall remodeling compared with low WSS.

Late results of bioabsorbable scaffolds implanted in spontaneous coronary artery dissection evaluated with computed tomography coronary angiography

Background Percutaneous coronary intervention (PCI) in spontaneous coronary artery dissection (SCAD) should be reserved for cases presenting with ongoing extensive ischaemia. Bioresorbable scaffolds (BVS) have emerged as an alternative to avoid permanent stenting, an especially attractive concept for this clinical scenario. However, data of late angiographic outcome of this device in SCAD is lacking. Purpose To evaluate the long-term angiographic outcome of BVS in the setting of SCAD using computed tomography coronary angiography (CTCA) Methods In this multicentre prospective study, high-risk SCAD patients treated with BVS were scheduled for a follow-up CTCA at least 2 years from implantation date. Acquisition was performed according to the current recommendations. All the studies were analysed in a central core laboratory by an independent level 3 expert in CTCA blinded to the clinical and angiographic results. For this purpose, a dedicated software for coronary analysis was used to quantify coronary stenosis and evaluate coronary wall. Results Thirty-four BVS were implanted in 15 SCAD patients (51±12 years-old; 87% female) from 7 different centres in Spain and United Kingdom. The most common presentation was STEMI (n=9, 60%). Target vessels included 11 left anterior descending arteries (73.3%), 3 right coronary arteries (20%) and 1 left circumflex coronary artery (6.7%). One patient received target lesion revascularisation due to scaffold shrinkage in a proximal right coronary artery at 13 months. CTCA was performed 2.4±0.7 years after BVS implantation. No scaffold thrombosis or significant stenosis were detected. Patency of all scaffolds was confirmed with a median luminal area of 5.52 mm2 (IQR: 3.74–6.95) and median stenosis of 11% (IQR: 4–15%). Regarding coronary wall tissue characterization of segments with BVS, there was 32±9.3% of plaque burden and a median plaque volume of 45.3 mm3 (IQR: 26.6–61.9). The most common component of the plaque was fibrous (85±9.4%). Compared to the proximal reference segments, BVS showed more plaque burden (32.2% vs 25.3%; p=0.017) and fibrous percentage (84.7% vs 75.1%; p=0.004) whereas less fibrofatty (6 vs 4.8 mm3; p=0.007) and necrotic volume (0.4 vs 1.2 mm3; p=0.029). BVS segments showed lower absolute minimal luminal area (5.5 vs 8.9 mm2; p=0.004) and diameter (2.7 vs 3.4 mm; p=0.004) compared to the reference segment; however, non-significant differences were seen in percentage stenosis, in keeping with normal vessel tapering. Conclusions In this series of SCAD treated with BVS, scaffolds showed a satisfactory late angiographic outcome, with no significant restenosis and an excellent minimal luminal area and optimal coronary wall healing observed. Funding Acknowledgement Type of funding source: None

Acute Stent Thrombosis Associated with Eptifibatide-Induced Profound Thrombocytopenia

Background. Eptifibatide is an inhibitor of the platelet glycoprotein (GP) IIb/IIIa receptor that is commonly used in patients undergoing percutaneous coronary intervention (PCI). Case. We describe a case of a 62-year-old female patient admitted with acute ST-elevation myocardial infarction (STEMI) treated by primary coronary intervention (primary PCI) with a drug-eluting stent placement. She developed profound thrombocytopenia within 8 hours of first administration of eptifibatide and subsequent acute stent thrombosis next day. Other causes of thrombocytopenia were excluded and intravascular ultrasound (IVUS) showed good stent expansion and opposition to the coronary wall. Platelet count gradually returned to normal after discontinuation of eptifibatide. Conclusion. Although Eptifibatide has been associated with the development of thrombocytopenia, to the best of our knowledge, this is the first case report in the medical literature that associates acute stent thrombosis and eptifibatide-induced thrombocytopenia.