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Background/purpose: Matching phasic pressure tracings between a fluid-filled catheter and high-fidelity pressure wire has received limited attention, although each part contributes half of the information to clinical decisions. We aimed to study the impact of a novel and automated method for improving the phasic calibration of a fluid-filled catheter by accounting for its oscillatory behavior., Methods/materials: Retrospective analysis of drift check tracings was performed using our algorithm that corrects for mean difference (offset), temporal delays (timing), differential sensitivity of the manifold transducer and pressure wire sensor (gain), and the oscillatory behavior of the fluid-filled catheter described by its resonant frequency and damping factor (how quickly oscillations disappear after a change in pressure)., Results: Among 2886 cases, correcting for oscillations showed a large improvement in 28 % and a medium improvement in 41 % (decrease in root mean square error >0.5 mmHg to <1 or 1-2 mmHg, respectively). 96 % of oscillators were underdamped with median damping factor 0.27 and frequency 10.6 Hz. Fractional flow reserve or baseline Pd/Pa demonstrated no clinically important bias when ignoring oscillations. However, uncorrected subcycle non-hyperemic pressure ratios (NHPR) displayed both bias and scatter., Conclusions: By automatically accounting for the oscillatory behavior of a fluid-filled catheter system, phasic matching against a high-fidelity pressure wire can be improved compared to standard equalization methods. The majority of tracings contain artifacts, mainly due to underdamped oscillations, and neglecting them leads to biased estimates of equalization parameters. No clinically important bias exists for whole-cycle metrics, in contrast to significant effects on subcycle NHPR., (Copyright © 2022 The Authors. Published by Elsevier Inc. All rights reserved.)

Introduction: Interventional cardiologists make adjustments in the presence of coronary calcifications known to limit stent expansion, but proper balloon sizing, plaque-modification approaches, and high-pressure regimens are not well established. Intravascular optical coherence tomography (IVOCT) provides high-resolution images of coronary tissues, including detailed imaging of calcifications, and accurate measurements of stent deployment, providing a means for detailed study of stent deployment., Objective: Evaluate stent expansion in an ex vivo model of calcified coronary arteries as a function of balloon size and high-pressure, post-dilatation strategies., Methods: We conducted experiments on cadaver hearts with calcified coronary lesions. We assessed stent expansion as a function of size and pressure of non-compliant (NC) balloons (i.e., nominal, 0.5, 1.0, and 1.5 mm balloons at 10, 20 and 30 atm). IVOCT images were acquired pre-stent, post-stent, and at all post-dilatations. Stent expansion was calculated using minimum expansion index (MEI)., Results: We analyzed 134 IVOCT pullbacks from ten ex-vivo experiments. The mean distal and proximal reference lumen diameters were 2.2 ± 0.5 mm and 2.5 ± 0.7 mm, respectively, 80% of times using a 3.0 mm diameter stent. Overall, based on stent sizing, a good expansion (MEI ≥ 80%) was reached using the 1:1 NC balloon at 20 atm, and expansion > 100% was reached using the 1:1 NC balloon at 30 atm. In the subgroup analysis, comparing low-calcified and high-calcified lesions, good expansion (MEI ≥ 80%) was reached using the 1:1 NC balloon at nominal pressure (10 atm) versus using 1:1 NC balloon at 30 atm, respectively. Significant vessel rupture was identified in all the vessels mainly upon post-dilatation with larger balloons, and 60% of the experiments (6 vessels, 3 in each calcium subgroup) presented rupture with the +1.0 mm NC balloon at 20 atm., Conclusion: When treating calcified lesions, good stent expansion was reached using smaller balloons at higher pressures without coronary injuries, whereas bigger balloons yielded unpredictable expansion even at lower pressures and demonstrated potential harmful damages to the vessels. As these findings could help physicians with appropriate planning of stent post-dilatation for calcified lesions, it will be important to clinically evaluate the recommended protocol., Competing Interests: Declaration of competing interest None of the authors have conflicts of interest regarding this paper., (Copyright © 2022. Published by Elsevier Inc.)

In this work, hemodynamic alterations in a patient-specific, heavily calcified coronary artery following stent deployment and post-dilations are quantified using in silico and ex-vivo approaches. Three-dimensional artery models were reconstructed from OCT images. Stent deployment and post-dilation with various inflation pressures were performed through both the finite element method (FEM) and ex vivo experiments. Results from FEM agreed very well with the ex-vivo measurements, interms of lumen areas, stent underexpansion, and strut malapposition. In addition, computational fluid dynamics (CFD) simulations were performed to delineate the hemodynamic alterations after stent deployment and post-dilations. A pressure time history at the inlet and a lumped parameter model (LPM) at the outlet were adopted to mimic the aortic pressure and the distal arterial tree, respectively. The pressure drop across the lesion, pertaining to the clinical measure of instantaneous wave-free flow ratio (iFR), was investigated. Results have shown that post-dilations are necessary for the lumen gain as well as the hemodynamic restoration towards hemostasis. Malapposed struts induced much higher shear rate, flow disturbances and lower time-averaged wall shear stress (TAWSS) around struts. Post-dilations mitigated the strut malapposition, and thus the shear rate. Moreover, stenting induced larger area of low TAWSS (<0.4 Pa) and lager volume of high shear rate (>2000 s -1 ), indicating higher risks of in-stent restenosis (ISR) and stent thrombosis (ST), respectively. Oscillatory shear index (OSI) and relative residence time (RRT) indicated the wall regions more prone to ISR are located near the malapposed stent struts., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Stent deployment in a calcified coronary artery is often associated with suboptimal outcomes such as stent underexpansion and malapposition. Post-dilation after stent deployment is commonly used for optimal stent implantation. There is no guideline for choosing the post-dilation balloon diameter and inflation pressure. In this work, ex-vivo/in-silico experiments were performed to investigate the efficacy of post-dilation balloon diameter and inflation pressure in improving the stent expansion in a calcified lesion. Post-dilations with three balloon diameters (3 mm, 3.5 mm, and 4 mm) were performed. For each balloon diameter, three inflation pressures (10 atm, 20 atm, and 30 atm) were sequentially applied. In ex-vivo experiments, optical coherence tomography images were acquired during the stenting procedure, i.e., pre- and post-deployment of 3 mm diameter stent, as well as after each post-dilation. The results from in-silico experiments were compared with ex-vivo experiments in terms of lumen area. In addition, stretch ratio analysis was developed to predict the stent-induced lumen area, along with the strain analysis and the in-silico experiments. Results have shown that target lumen area could be achieved with an oversized nominal balloon diameter of +0.5 mm (i.e., 0.5 mm greater than reference lumen diameter) at an inflation pressure of 20 atm. After each post-dilation, fibrotic tissue demonstrated a larger strain, contributing to improved lumen gain. However, minimal changes were observed in calcification. Moreover, a strong correlation (R 2  = 0.95) between the stretch ratio of fibrotic tissue and lumen area after each post-dilation was observed. This indicated that the morphology of the fibrotic tissue could be a potential marker to predict the lumen gain. The detailed mechanistic quantifications of a single lesion cannot be generalized to all clinical cases. However, this work could be used to provide a fundamental understanding of the post-dilations, to develop experimental protocols for producing generalized guidelines, and to exploit their potential for optimal pre- and post-stent strategies., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Objective: To evaluate the feasibility of using the DyeVert™ Plus EZ Contrast Reduction System in optical coherence tomography (OCT)-guided percutaneous coronary intervention (PCI) procedures and to assess OCT image quality., Background: OCT is employed as a powerful intravascular imaging modality; however, it requires blood displacement via contrast injection during image acquisition, thereby posing risk of nephrotoxicity. The DyeVert System is designed to reduce and facilitate monitoring of contrast media volume (CMV) delivered, without diminishing image quality., Methods: We conducted a prospective clinical feasibility study to determine whether the DyeVert System is non-inferior to manual contrast injection in reducing CMV without lessening image quality during OCT-guided PCI procedures. Eligible participants were ≥ 18 years of age, indicated for coronary OCT, and able to provide informed consent. The primary endpoint was CMV saved during angiography; the secondary endpoint was image quality as evaluated by operators in real time and by an independent core laboratory that also assessed images from a control group that underwent comparable procedures performed without the DyeVert System., Results: Fourteen participants underwent 15 coronary OCT procedures using the DyeVert System. Mean age among participants was 67 ± 11 years, and 11 (78%) were male. Mean eGFR was 71 ± 20 mL/min/1.73m 2 . Mean attempted CMV administration was 342.01 ± 129.8 mL; mean CMV delivered was 216.21 ± 88.87 mL, representing CMV savings of 37.5 ± 5.3%. Results from quantified OCT analysis suggest that the clear region of interest (ROI) in the DyeVert group was non-inferior (p < .0001) to the control group. There were no device-related adverse events., Conclusions: The DyeVert™ Plus EZ Contrast Reduction System reduced CMV and preserved an image quality that was non-inferior to OCT-guided PCI procedures without using the contrast reducing device., Competing Interests: Declaration of competing interest Dr. Bezerra receives consulting fees from Abbott Vascular, Inc. Other authors report no relevant conflicts of interest with this manuscript., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Introduction: A volumetric approach to measure stent expansion derived from optical coherence tomography (OCT) is superior in regards to clinical outcomes when compared to the conventional method. The current software already performs a semi-automatic assessment and it is available as a clinical tool, however data is still scarce. We evaluated the stent expansion analysis that uses a volumetric vessel model, called minimum expansion index - MEI and compared to the conventional model, which utilizes the minimum stent area expansion (MSAx) indexed to the references, and its potential impact on procedural decision-making strategy in percutaneous coronary intervention., Methods: This was a prospective, all-comers single center study, from all patients undergoing OCT-guided PCI between September 2018 and May 2019. We utilized the APTIVUE™ OPTIS 5.2 software (Abbott, Santa Clara, CA) to evaluate MEI and MSAx measurements after reference adjustments., Results: We included 100 patients with mean age of 64 ± 12.5 years, 68% were men, and the main arteries analyzed through OCT were LAD (48%), RCA (31%) and LCx (21%). The mean MEI was 77.6% ± 16.7% and the mean MSAx was 71.6% ± 16.9%. MEI location differed from MSAx in 70% of cases, and in those cases the mean distance between MEI and MSAx was 15.3 mm ± 12.4 mm. In 53% of the times, the stent underexpansion based on MEI was located proximally to the MSAx by 18.1 mm ± 11.8 mm. Furthermore, in 42% of the total cases, MEI would change the intervention strategy based on the stent underexpansion being in a different location ≥10 mm in comparison to MSAx (34%) associated with the discrepancy between expansion indexes for MEI and MSAx (22%)., Conclusion: We concluded that MEI location did not correlate to the conventional MSAx in two thirds of the cases. Moreover, compared to MEI, the MSAx assessment yielded lower expansion values in different stent positions, potentially changing the appropriate post-stent optimization, which thus would impact the decision-making strategy in almost half of the patients., Competing Interests: Declaration of competing interest Dr. Bezerra is a consultant for Abbott Vascular Inc. None of the other authors have conflicts of interest., (Copyright © 2020 Elsevier Inc. All rights reserved.)

The rate of in-stent restenosis (ISR) has become increasingly prevalent with the exponential growth in stent implantation due to an aging population and a higher life expectancy, in addition to the high rates of obesity and diabetes. In this prospective, single operator, all-comer study, we sought to analyze the performance of ELCA followed by bioresorbable vascular scaffold (BVS) placement in patients undergoing percutaneous coronary intervention (PCI) for ISR. A total of 13 patients had ISR treated with a combination of ELCA and BVS, with 9 patients having matched OCT pre, post ELCA and post BVS. Mean age was 65 ± 11.22 and 83% of the patients were male. Hypertension and dyslipidemia were present in 100% of the patients and smoking and diabetes in 50%. After the procedure, we did not detect residual stenosis over 10% in any patient, resulting in a technical success of 100%. No patients had MACE during their hospital stay or within the next six months, resulting in a procedure success of 100%. The mean lumen area increased 0.35 mm 2 from pre procedure to post ELCA and 3.58 mm 2 from post ELCA to post BVS. The final difference, from pre procedure to post BVS, was a 3.93 mm 2 lumen area gain. The mean lumen diameter increased 0.11 mm from baseline to ELCA, 0.95 mm from post laser to BVS implantation and 1.06 mm from pre procedure to post BVS. The NIH area reduced 0.48 mm 2 from pre to post ELCA, 1.13mm 2 from post ELCA to BVS implantation and 1.61 mm 2 from baseline to post BVS implantation. We conclude that ELCA is a safe and feasible debulking method to approach ISR, with high rates of post-procedural BVS success, within six months follow-up., Competing Interests: Declaration of competing interest Dr. Bezerra is a consultant for Philips and Abbott. None of the other authors have conflicts of interest., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Background: Fractional flow reserve derived from computed tomography (FFRct) has shown higher accuracy for detection of significant coronary artery disease (CAD) compared to coronary computed tomography angiography (CCTA). The performance of a combined comprehensive qualitative interpretation of both CCTA and FFRct in patient management is unknown. We aimed to explore the clinical application of this combined approach., Methods: We retrospectively reviewed cases referred to FFRct testing at our institution over a one-year period. Patients had documentation of whether invasive coronary angiography (ICA) was performed and revascularization were needed. Interpretations and recommendations of the adopted comprehensive approach (C-FFRct), that took into account focal versus diffuse disease, depth of ischemia and myocardium at risk, were compared to those of CCTA (binary > 50% stenosis) alone and FFRct binary approach (FFRct ≤ 0.8). C-FFRct performance was measured against the decision made upon revascularization., Results: A total of 207 cases were referred to FFRct testing, 163 (79%) accepted and 44 (21%) rejected for quality. C-FFRct changed interpretations and recommendations of 39 (24%) and 14 (9%) CCTA and FFRct, respectively. ICA was deferred in 32 (59%) and 13 (32%) cases; whereas ICA referral rate was 7 (6%) and 1 (0.8%) cases, based on CCTA and FFRct, respectively. No major cardiac events were observed during follow up time (median = 6 months). C-FFRct sensitivity, specificity, and accuracy compared to decision upon revascularization were 89%, 79% and 82%. C-FFRct number needed to treat was 4, and 6, compared to CCTA and FFRct, respectively., Conclusion: FFRct is a feasible tool to improve the diagnostic performance of CCTA in CAD real-world workup. However, qualitative interpretation of the FFRct report combined with CCTA findings may yield more impactful results on patient management. Further prospective studies are warranted to validate the application of this approach and better define its components., (Copyright © 2019. Published by Elsevier Inc.)

Objectives: This study sought to compare conventional methodology (CM) with a newly described optical coherence tomography (OCT)-derived volumetric stent expansion analysis in terms of fractional flow reserve (FFR)-derived physiology and device-oriented composite endpoints (DoCE)., Background: The analysis of coronary stent expansion with intracoronary imaging has used CM that relies on the analysis of selected single cross-sections for several decades. The introduction of OCT with its ability to perform semiautomated volumetric analysis opens opportunities to redefine optimal stent expansion., Methods: A total of 291 lesions treated with post-stent OCT and FFR were enrolled. The expansion index was calculated by using a novel volumetric algorithm and was defined as: ([actual lumen area / ideal lumen area] × 100) for each frame of the stented segment. The minimum expansion index (MEI) was defined as the minimum value of expansion index along the entire stented segment. MEI and conventional lumen expansion metrics were compared for the ability to predict post-stent low FFR (<0.90) and DoCE at 1 year., Results: There was a stronger correlation between MEI and final FFR, compared with CM and final FFR (r = 0.690; p < 0.001) versus (r = 0.165; p = 0.044). MEI was significantly lower in patients with DoCE than those without DoCE (72.18 ± 8.23% vs. 81.48 ± 11.03%; p < 0.001), although stent expansion by CM was similar between patients with and without DoCE (85.05 ± 22.19% and 83.73 ± 17.52%; p = 0.858), respectively., Conclusions: OCT analysis of stent expansion with a newly described volumetric method, but not with CM, yielded data that were predictive of both an acute improvement in FFR-derived physiology and DoCE., (Copyright © 2018 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.)

Background and Aims: Accumulation of advanced glycation end products (AGEs) can be measured non-invasively by skin autofluorescence (SAF) whose values are elevated in patients with cardiovascular disease (CVD). Optical coherence tomography (OCT) is an intravascular imaging modality that could allow visualization of plaque composition. We aim to examine the relationship between SAF and plaque composition evaluated by frequency-domain OCT in patients with CVD., Methods: We prospectively enrolled 108 patients with CVD, who underwent OCT images during percutaneous coronary intervention (PCI). We divided the population into two groups: high SAF group (greater than or equal to 2.6) and low SAF one (less than 2.6). OCT findings were then compared between high and low SAF groups., Results: The high SAF group showed much more thin cap fibroatheroma (TCFA), and calcified or ruptured plaques compared to the low SAF group. In multivariable analysis, low-density lipoprotein-cholesterol (LDL) (odds ratio: 1.15; 95% confidence interval: 1.00 to 1.32; p = 0.043), TG (OR for 10 mg/dl increase: 1.04; 95% confidence interval: 1.01 to 1.13; p = 0.016), and SAF (4.28; 1.86 to 9.84; p < 0.001) were independent correlates of TCFA, whereas SAF (2.61; 1.02 to 6.70; p = 0.047), estimated glomerular filtration rate (0.68; 0.49 to 0.93; p = 0.017) and LDL (1.19; 1.01 to 1.41; p = 0.037) were independent predictors of ruptured plaques. SAF and diabetes were independently associated with calcified plaques., Conclusions: High SAF were associated with plaque vulnerability in patients with CVD, thus suggesting the clinical utility of SAF measurement in identifying high-risk patients for future cardiovascular events., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Significant progress has been made in the percutaneous coronary intervention technique from the days of balloon angioplasty to modern-day metallic drug-eluting stents (DES). Although metallic stents solve a temporary problem of acute recoil following balloon angioplasty, they leave behind a permanent problem implicated in very late events (in addition to neoatherosclerosis). BRS were developed as a potential solution to this permanent problem, but the promise of these devices has been tempered by clinical trials showing increased risk of safety outcomes, both early and late. This is not too dissimilar to the challenges seen with first-generation DES in which refinement of deployment technique, prolongation of dual antiplatelet therapy, and technical iteration mitigated excess risk of very late stent thrombosis, making DES the treatment of choice for coronary artery disease. This white paper discusses the factors potentially implicated in the excess risks, including the scaffold consideration and deployment technique, and outlines patient and lesion selection, implantation technique, and dual antiplatelet therapy considerations to potentially mitigate this excess risk with the first-generation thick strut Absorb scaffold (Abbott Vascular, Abbott Park, Illinois). It remains to be seen whether these considerations together with technical iterations will ultimately close the gap between scaffolds and metal stents for short-term events while at the same time preserving options for future revascularization once the scaffold bioresorbs., (Copyright © 2017 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.)

Objectives: This study sought to determine the diagnostic performance of noninvasive fractional flow reserve (FFR) derived from coronary computed tomography angiography (CTA) (FFR CT ) for the diagnosis of lesion-specific ischemia in nonculprit vessels of patients with recent in ST-segment elevation myocardial infarction (STEMI)., Background: In patients with stable angina, FFR CT has high diagnostic performance in identification of ischemia-causing lesions. The potential value of FFR CT for assessment of multivessel disease in patients with recent STEMI has not been evaluated., Methods: Coronary CTA with calculation of FFR CT and invasive coronary angiography with FFR were performed 1 month after STEMI in patients with multivessel disease. Coronary CTA and invasive coronary angiography stenosis >50% were considered obstructive. Lesion-specific ischemia was assumed if FFR CT was ≤0.80. FFR ≤0.80 was the reference standard. To evaluate the influence of vessel size, the total coronary vessel lumen volume relative to left ventricular mass (volume-to-mass ratio) was calculated and compared with that of patients with stable angina., Results: The study evaluated 124 nonculprit vessels from 60 patients. Accuracy, sensitivity, and specificity of FFR CT were 72%, 83%, and 66% versus 64% (p = 0.033), 93% (p = 0.15), and 49% (p < 0.001) for CTA and 72% (p = 1.00), 76% (p = 0.46), and 70% (p = 0.54) for invasive coronary angiography. Following STEMI, median volume-to-mass ratio was lower than in patients with stable angina, 53 versus 65 mm 3 /g (p = 0.009). In patients with volume-to-mass ratio ≥65 mm 3 /g (upper tertile) accuracy, sensitivity, and specificity of FFR CT were all 83% versus 56% (p = 0.009), 75% (p = 0.61), and 44% (p = 0.003) in patients with <49 mm 3 /g (lower tertile)., Conclusions: The diagnostic performance of FFR CT for staged detection of ischemia in STEMI patients with multivessel disease is moderate. STEMI patients have a smaller vessel volume than do patients with stable angina. The diagnostic performance of FFR CT is influenced by the volume-to-mass ratio. This study does not support routine use of FFR CT in the post-STEMI setting. (Assessment of Coronary Stenoses Using Coronary CT-Angiography and Noninvasive Fractional Flow Reserve; NCT01739075)., (Copyright © 2017 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.)

Background: The relationship between N-terminal pro-brain natriuretic peptide (NT-proBNP) and cardiac structural or functional anomalies in pre-clinical, asymptomatic Asian populations has not been well identified., Methods: From October 2005 to March 2008, we enrolled consecutive asymptomatic adults with preserved global left ventricular (LV) function (ejection fraction>50%) who underwent annual cardiovascular health survey. Circulating NT-proBNP was used to identify echo-defined cardiac structural/functional anomalies and compared to current recommended cut-off from the European Society of Heart Failure., Results: Among 976 eligible subjects, 371 (38%) had structural heart diseases. Echocardiography-based left atrial diameter (Coef: 71.2), diastolic dysfunction (Coef: 35.4), and presence of pulmonary hypertension (Coef: 83.1) or valvular heart disease (Coef: 56.1, all p<0.05) of any form independently predicted circulating NT-ProBNP. NT-ProBNP cut-off values of 32.8 and 115.4pg/ml for subjects aged ≤ and >75years, respectively, demonstrated areas under the receiver operating characteristic curve of 0.76 (95% CI: 0.73-0.80) and 0.70 (95% CI: 0.52-0.88) for predicting structural or functional anomaly., Conclusion: We examined the feasibility of NT-ProBNP for identifying cardiac structural and functional anomaly in an asymptomatic ethnic Taiwanese population with a relatively lower cut-off value, indicating its potential role for pre-clinical screening of Asian patients., (Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.)

Objectives: The aim of the present study was to evaluate vascular healing of the bioengineered COMBO Dual Therapy Stent compared with a cobalt-chromium (CoCr) everolimus-eluting stent (EES) as assessed by optical coherence tomography in patients with acute coronary syndromes., Background: CD34+ cells promote endothelial repair after vascular injury. The bioengineered COMBO Dual Therapy Stent combines CD34+ cell-capturing technology with abluminal sirolimus release, but more data from clinical studies evaluating the vascular response are needed., Methods: In a prospective randomized multicenter clinical trial, 60 patients with acute coronary syndromes were randomized 1:1 to COMBO or CoCr EES implantation. The primary endpoint was the percentage of uncovered stent struts per stent. Stent assessment by optical coherence tomography was performed at baseline and at 60 days, followed by independent core laboratory analysis., Results: The percentage of uncovered struts per stent was higher with the COMBO than the CoCr EES at 60 days (median 14.7% vs. 7.7%; p = 0.04). However, no significant difference in uncovered stent struts was observed in the strut level-based analysis at 60 days, which also accounted for clustering (COMBO vs. CoCr EES; 13.6% vs. 6.9%; p = 0.09; generalized linear mixed models-adjusted analysis). Neointimal thickness at 60 days was lower with the COMBO compared with the CoCr EES (median 30.17 vs. 50.26 μm; p = 0.02; stent-level analysis). There were no significant differences in the frequency of major adverse cardiac events and each component of major adverse cardiac events within the study population between the 2 groups at 30, 60, 180, 360, and 540 days post-procedure. No target vessel stent thrombosis has been documented within 540 days., Conclusions: The present multicenter, prospective clinical study for the first time compared the vascular response of the bioengineered COMBO Dual Therapy Stent with a CoCr EES in patients early after acute coronary syndrome by using intracoronary optical coherence tomographic analysis. The percentage of uncovered stent struts per stent was somewhat higher after COMBO versus CoCr EES implantation as detected by optical coherence tomography, associated with reduced neointimal thickness., (Copyright © 2017 American College of Cardiology Foundation. All rights reserved.)

Background: Kissing-balloon technique (KBT) is commonly performed during percutaneous coronary intervention of distal unprotected left main coronary artery (ULM) aiming at obtaining optimal opening of the side branch (left circumflex artery; LCX) ostium. Nonetheless, detailed evaluation of vascular response to stents in LCX ostium is lacking. We therefore evaluated the vascular response to different drug-eluting stents (DES) in ostial LCX after ULM by means of optical coherence tomography (OCT)., Methods: We prospectively enrolled 38 consecutive patients with ULM disease, who were treated with single-stent procedure using DES, crossover the ULM-left anterior descending artery (LAD) followed by KBT. Twelve patients were treated with sirolimus-eluting stents (SES) and 26 patients were treated with everolimus-eluting stents (EES). OCT was conducted at post-PCI and 9-month follow-up. We evaluated the DES-vessel interactions and number of stent struts at the side branch (LCX) ostium (SO) at post-PCI, and compared the narrowing of ostial area at LCX between SES and EES., Results: Post-procedure, the number of stent struts at SO was significantly higher in SES compared to EES (median 14.47% vs 0.19%, p<0.001). The narrowing of LCX ostial area at follow-up was more pronounced in SES compared with EES (29.16% vs 2.46%, respectively, p<0.001). Linear regression analysis showed a high correlation between the number of stent struts in LCX ostium and ostial area narrowing (r=0.771, p<0.001)., Conclusions: OCT showed differences between EES- and SES-vessel interactions at ULM bifurcation PCI. Number of LCX ostium struts at post-PCI impacted the narrowing of ostial area at 9-month follow-up., (Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.)

Background: Optical coherence tomography (OCT) has contributed to a better understanding of in-stent restenosis (ISR); however, studies evaluating ISR pattern after two-stent technique in unprotected left main (ULM) are lacking. We aim to evaluate the ISR pattern of proximal LAD and LCX after two-stent technique in ULM., Methods: We performed OCT in 26 patients with isolated or combined ISR (identified by angiography as >50%) after two stent implantation in the proximal LCX and LAD. Finally, 13 LAD and 22 LCX ISR lesions underwent OCT assessments. OCT analyses were undertaken in the proximal segments of the LAD and LCX. In addition, we compared OCT findings in the flow divider (FD) and lateral wall (LW)., Results: In both the LAD and LCX, the distance from the ostium to the minimum lumen area (MLA; LAD, 2.00mm [1.00, 3.00]; LCX, 1.00mm [0.00, 1.80] distal to ostium) was short. Uncovered struts were more common on the FD side compared with the LW in the LAD (6.25% [0.00, 20.00] vs 0.00% [0.00, 0.00], respectively, p=0.016) and LCX (11.32% [0.00, 19.44] vs 0.00% [0.00, 4.55], respectively, p<0.001). Conversely, neointimal hyperplasia (NIH) was significantly thicker on the FD side compared with the LW in the LCX (0.31mm [0.19, 0.47] vs 0.15mm [0.09, 0.31], p<0.001)., Conclusions: While uncovered struts were more commonly found on the FD side of both arteries, NIH was significantly thicker on the FD side compared with the LW in the LCX. These unique findings might indicate inferior outcomes after two-stent techniques in ULM bifurcation lesions., (Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.)

Atrial fibrillation is prevalent and percutaneous left atrial appendage (LAA) closure is increasingly performed worldwide. This procedure is technically challenging and the success and procedural complexities depend on anatomy of the LAA and surrounding structures. These are readily depicted on cardiac computed tomography angiography (CCTA), which offers unique imaging planes. CCTA allows not only preplanning anatomic LAA assessment, but can also be used to evaluate for pre-existing LAA thrombus, and done postprocedure for surveillance for device-related thrombus, residual leak, and complications. In this article, we review the practical utility of CCTA for LAA closure., (Copyright © 2016 Canadian Cardiovascular Society. Published by Elsevier Inc. All rights reserved.)

Aim: To describe the relationship between a novel measurement of peri-arotic root fat and ultrasound measures of carotid artery remodeling., Materials and Methods: We studied 1492 consecutive subjects (mean age: 51.04 ± 8.97 years, 27% females) who underwent an annual cardiovascular risk survey in Taiwan. Peri-aortic root fat (PARF) was assessed by cardiac CT using three-dimensional (3D) volume assessment. Carotid artery morphology and remodeling were assessed by ultrasound. We explored the relationships between PARF volumes, cardiometabolic risk profiles and carotid morphology and remodeling., Results: Mean PARF volume in current study was 20.8 ± 10.6 ml. PARF was positively correlated with measures of general adiposity, systemic inflammation, and several traditional cardiometabolic risk profiles (all p < 0.001) and successfully predicted metabolic syndrome (MetS) (AUROC: 0.75, 95%, confidence interval: 0.72-0.77). Higher PARF was independently associated with increased carotid artery intima-media thickness (IMT) (β-coef.: 0.08) and diameter (β-coef.: 0.08, both p < 0.05) after accounting for age, sex, BMI and other cardiovascular risk factors. The addition of PARF beyond metabolic syndrome components significantly provided incremental prediction value for abnormal IMT (ΔAUROC: 0.053, p = 0.0021)., Conclusion: Peri-aortic root fat is associated with carotid IMT, even after adjustment for cardiometabolic risks, age and coronary atherosclerosis. Further research studies are warranted to identify the mediators of downstream pathophysiologic effects on carotid arteries by PARF and understand the mechanisms related to this correlation., (Copyright © 2016 Society of Cardiovascular Computed Tomography. Published by Elsevier Inc. All rights reserved.)

Objectives: The present study sought to determine whether optical coherence tomography (OCT) guidance results in a degree of stent expansion comparable to that with intravascular ultrasound (IVUS) guidance., Background: The most important predictor of adverse outcomes (thrombosis and restenosis) after stent implantation with IVUS guidance is the degree of stent expansion achieved., Methods: We compared the relative degree of stent expansion (defined as the minimal stent area divided by the mean of the proximal and distal reference lumen areas) after OCT-guided stenting in patients in the ILUMIEN (Observational Study of Optical Coherence Tomography [OCT] in Patients Undergoing Fractional Flow Reserve [FFR] and Percutaneous Coronary Intervention) (N = 354) and IVUS-guided stenting in patients in the ADAPT-DES (Assessment of Dual Antiplatelet Therapy With Drug-Eluting Stents) study (N = 586). Stent expansion was examined in all 940 patients in a covariate-adjusted analysis as well as in 286 propensity-matched pairs (total N = 572)., Results: In the matched-pair analysis, the degree of stent expansion was not significantly different between OCT and IVUS guidance (median [first, third quartiles] = 72.8% [63.3, 81.3] vs. 70.6% [62.3, 78.8], respectively, p = 0.29). Similarly, after adjustment for baseline differences in the entire population, the degree of stent expansion was also not different between the 2 imaging modalities (p = 0.84). Although a higher prevalence of post-PCI stent malapposition, tissue protrusion, and edge dissections was detected by OCT, the rates of major malapposition, tissue protrusion, and dissections were similar after OCT- and IVUS-guided stenting., Conclusions: In the present post-hoc analysis of 2 prospective studies, OCT and IVUS guidance resulted in a comparable degree of stent expansion. Randomized trials are warranted to compare the outcomes of OCT- and IVUS-guided coronary stent implantation., (Copyright © 2015 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.)

Proximal optimization technique and final kissing balloon inflations with noncompliant balloons facilitate success with coronary bifurcation intervention. The use of bioresorbable vascular scaffolds has been postulated to reduce the risk of in-stent restenosis, a particular problem with bifurcation intervention. We present a case of bifurcation intervention in a 49-year-old woman, using for the first time, proximal optimization and kissing balloon inflation within bioresorbable vascular scaffolds, using optical coherence tomography guidance., (Copyright © 2014 Canadian Cardiovascular Society. Published by Elsevier Inc. All rights reserved.)

Background: Fractional flow reserve (FFR) is the standard of reference for assessing the hemodynamic significance of coronary stenoses in patients with stable coronary artery disease. Noninvasive FFR derived from coronary CT angiography (FFRCT) is a promising new noninvasive method for assessing the physiologic significance of epicardial stenoses. The reproducibility of FFRCT has not yet been established., Objective: The aim of this study was to evaluate the variation of repeated analyses of FFRCT per se and in the context of the reproducibility of repeated FFR measurements., Methods: Coronary CT angiography and invasive coronary angiography with repeated FFR measurements were performed in 28 patients (58 vessels) with suspected stable coronary artery disease. Based on the coronary CT angiography data set, FFRCT analyses were performed twice by 2 independent blinded analysts., Results: In 12 of 58 (21%) vessels FFR was ≤ 0.80. The standard deviation for the difference between first and second FFRCT analyses was 0.034 vs 0.033 for FFR repeated measurements (P = .722). Limits of agreement were -0.06 to 0.08 for FFRCT and -0.07 to 0.06 for FFR. The coefficient of variation of FFRCT (CVFFRct) was 3.4% (95% confidence interval [CI], 1.4%-4.6%) vs 2.7% (95% CI, 1.8%-3.3%) for FFR. In vessels with mean FFR ranging between 0.70 and 0.90 (n = 25), the difference between the first and second FFRCT analyses was 0.035 and FFR repeated measurements was 0.043 (P = .357), whereas CVFFRct was 3.3% (95% CI, 1.5%-4.3%) and coefficient of variation for FFR was 3.6% (95% CI, 2.3%-4.6%)., Conclusions: The reproducibility of both repeated FFRCT analyses and repeated FFR measurements is high., (Copyright © 2014 Society of Cardiovascular Computed Tomography. Published by Elsevier Inc. All rights reserved.)

Objectives: The goal of this study was to investigate carotid plaque characteristics in symptomatic versus asymptomatic patients with the use of nonocclusive optical coherence tomography (OCT)., Background: The identification of asymptomatic patients with carotid disease who are at risk of stroke remains a challenge. There is an increasing awareness that plaque characteristics may best risk-stratify this population. We hypothesized that OCT, a new high-resolution (∼ 10 μm) imaging modality, might be useful for the identification of low-risk versus high-risk carotid plaque features and help us to understand the relationship between carotid diameter stenosis and plaque morphology to ischemic stroke., Methods: Fifty-three patients undergoing diagnostic carotid angiography were studied with OCT. Data analysis was carried out by imaging experts who were unaware of the clinical characteristics of the study population., Results: Plaque with American Heart Association type VI complicated features was more common in symptomatic than asymptomatic patients (74.1% vs. 36.4%, p = 0.02). This was largely driven by differences in the incidence of thin-cap fibroatheroma with rupture (40.7% vs. 13.6%, p = 0.056) and thrombus (67.7% vs. 36.4%, p = 0.034). Conversely, non-type VI plaques were more common in asymptomatic than symptomatic patients (63.6% vs. 25.9%, p = 0.02). No association between the degree of stenosis and plaque morphology was identified., Conclusions: This retrospective analysis of carotid OCT data supports the hypothesis that the evaluation of carotid plaque characteristics with this high-resolution imaging technique has the potential to alter the understanding and treatment of carotid artery disease., (Copyright © 2014 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.)

The following case report describes using carbon dioxide (CO2) as contrast media for intravascular optical coherence tomography (OCT) imaging in the superficial femoral artery. For initial OCT imaging, 20 mL of iodinated contrast was used during automated pullback. This was followed by 20 mL of hand-injected dextran 40 in normal saline, and finally hand-injected 50 mL of CO2. CO2 gave comparable erythrocyte clearance and imaging quality compared with dextran and iodinated contrast. To our knowledge, this is the first reported case using both dextran and CO2 with OCT imaging of the superficial femoral artery. Using CO2 is a viable option in patients with contraindications to contrast or dextran use., (Copyright © 2014 Society for Vascular Surgery. Published by Mosby, Inc. All rights reserved.)

Background: HIV-infection is characterized by chronic immune activation that persists despite effective antiretroviral therapy (ART) and is associated with elevated cardiovascular risk. Whether specific perivascular fat depots are associated with inflammation in HIV is unknown., Methods: In a cross-sectional study, epicardial (EAT) and thoracic periaortic (TAT) adipose tissue volumes were measured by computed tomography in 100 HIV-infected adults, on stable ART, with LDL-cholesterol ≤130 mg/dL and evidence of heightened T-cell activation (CD8+CD38+HLA-DR+ ≥19%) or increased inflammation (high sensitivity C-reactive protein ≥2 mg/L)., Results: Overall, 77% were males and 70% African American. Mean (standard deviation) age and body mass index were 47 (10) years and 28 (6.4) kg/m(2), respectively. All subjects had HIV-1 RNA <1000 copies/mL with mean (standard deviation) CD4+ T cell count of 665 (280) cells/μL; 50% were on a protease inhibitor. EAT and TAT were correlated with each other (r = 0.766, p < 0.0001). Both were associated with metabolic syndrome, atherogenic lipid profile, insulin resistance, total and central body fat, serum biomarkers of inflammation, and soluble CD163, but not with cellular immune activation markers. In multivariable models that adjusted for age, sex, and other measures of adiposity, both perivascular fat depots were independently associated with the presence of coronary calcium., Conclusions: Perivascular fat is associated with soluble CD163, biomarkers of inflammation, insulin resistance, and subclinical atherosclerosis in this population of virologically suppressed HIV-infected patients on ART. The association of perivascular fat with coronary artery calcification appears to be independent of other measures of adiposity., (© 2013.)

Objectives: This study sought to assess stent-vessel interactions after drug-eluting stent (DES) implantation in unprotected left main coronary artery (ULM) by frequency-domain optical coherence tomography (FD-OCT)., Background: Percutaneous coronary intervention using DES in ULM has been increasingly performed in routine practice. Recently, FD-OCT assessments of DES-vessel interactions have been used as surrogates for DES safety; however, there are no FD-OCT studies in ULM., Methods: We prospectively enrolled 33 consecutive patients with ULM disease treated with sirolimus- (n = 11) and everolimus-eluting stents (n = 22). FD-OCT assessments were performed post-percutaneous coronary intervention and at 9-month follow-up. Three different segments of ULM were compared: distal (DIS), bifurcation (BIF), and ostial-body (BODY). The primary endpoints were percentages of uncovered and malapposed struts at 9-month follow-up, and the secondary endpoint was neointimal hyperplasia area., Results: We analyzed 25,873 stent struts. Significant differences were demonstrated for percentage of uncovered struts (3.4%, 11.7%, and 18.7%, respectively for DIS, BIF, and BODY; p < 0.05 for all the comparisons). Malapposition was also more common in BODY (5.3%) than in DIS (0.6%) and BIF (2.0%) segments (p < 0.05 for BODY vs. DIS, and BODY vs. BIF). Equivalent neointimal hyperplasia areas were demonstrated in all segments. Acute malapposition rates led to different patterns of DES-vessel interactions at 9-month follow-up., Conclusions: Distinct patterns of DES-vessel interactions were demonstrated in different segments of ULM. Acute stent strut malapposition affects these findings., (Copyright © 2013 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.)

Introduction: Coronary CT angiography (CTA) is an established noninvasive method for visualization of coronary artery disease. However, coronary CTA lacks physiological information; thus, it does not permit differentiation of ischemia-causing lesions. Recent advances in computational fluid dynamic techniques applied to standard coronary CTA images allow for computation of fractional flow reserve (FFR), a measure of lesion-specific ischemia. The diagnostic performance of computed FFR (FFRCT) compared with invasively measured FFR is not yet fully established., Methods/design: HeartFlowNXT (HeartFlow analysis of coronary blood flow using coronary CT angiography: NeXt sTeps) is a prospective, international, multicenter study designed to evaluate the diagnostic performance of FFRCT for the detection and exclusion of flow-limiting obstructive coronary stenoses, as defined by invasively measured FFR as the reference standard. FFR values ≤ 0.80 will be considered to be ischemia causing. All subjects (N = 270; 10 investigative sites) will undergo coronary CTA (single- or dual-source CT scanners with a minimum of 64 slices) and invasive coronary angiography with FFR. Patients with insufficient quality of coronary CTA will be excluded. Blinded core laboratory interpretation will be performed for FFRCT, invasive coronary angiography, and FFR. Stenosis severity by coronary CTA will be evaluated by the investigative site in addition to a blinded core laboratory interpretation. The primary objective of the study is to determine the diagnostic performance of FFRCT compared with coronary CTA alone to noninvasively determine the presence of hemodynamically significant coronary lesions. The secondary end point comprises assessment of diagnostic accuracy, sensitivity, specificity, positive predictive value, and negative predictive value of FFRCT., (Copyright © 2013 Society of Cardiovascular Computed Tomography. Published by Elsevier Inc. All rights reserved.)

Objectives: This study sought to investigate the frequency, predictors, and detailed qualitative and quantitative assessment of optical coherence tomography (OCT)-detected stent edge dissections. Its impact on subsequent management and clinical outcomes were also investigated., Background: OCT is a high-resolution imaging modality that can lead to more frequent recognition and accurate assessment of vascular injuries during percutaneous coronary intervention (PCI)., Methods: From September 2010 to June 2011, all patients with OCT post-PCI were enrolled. Edge dissections were defined as disruptions of the arterial lumen surface in both the 5-mm distal and proximal stent edges. Qualitative and quantitative analyses of all edges were performed at 0.2-mm intervals., Results: In total, 395 edges (249 lesions in 230 patients) were analyzed. The overall incidence of OCT-detected edge dissection was 37.8%, and most (84%) were not apparent on angiography. Independent predictors for OCT-detected dissections were presence of atherosclerotic plaque at stent edges, calcification angle, minimum fibrous cap thickness, thin-cap fibroatheromas, stent/lumen eccentricity, and vessel overstretching. Mean dissection length measured 2.04 ± 1.60 mm, 96.2% appeared as flaps, and 52.8% extended beyond the intima/atheroma layer. Additional stenting was performed in 22.6% of all dissections, which were longer, had bigger dimensions, and promoted deeper vascular injury. The 12-month major adverse cardiac event rate was similar between patients with (7.95%) and without (5.69%, p = 0.581) dissections., Conclusions: High rates of stent edge dissections were detected by OCT, usually related to the presence of atherosclerosis at stent edges and to PCI technique. Detailed OCT assessment of dissection severity was possible and affected the subsequent management of this complication. Non-flow-limiting, small, and superficial dissections left untreated proved benign., (Copyright © 2013 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.)

Intravascular optical coherence tomography is a high-resolution invasive imaging modality that allows the evaluation of vascular responses after stent implantation in a micron-scale level. We describe for the first time two patients with very late vascular response after carotid artery stenting that exhibit two different patterns of low-signal intensity (LSI), "ill-appearing" neointima: the first patient shows layered LSI neointima leading to stent restenosis, coupled with the presence of intraluminal thrombus, whereas the second patient demonstrates another pattern of non-restenotic LSI stent strut coverage, suggestive of lipid laden neointima (ie, "neoatherosclerosis"), recently associated with stent failure in coronary arteries., (Copyright © 2013 Society for Vascular Surgery. Published by Mosby, Inc. All rights reserved.)

Background: Optical coherence tomography (OCT) is a novel intravascular imaging modality with excellent spatial resolution. This study explored the utility of OCT in cardiac transplantation for the detection and characterization of early changes associated with coronary allograft vasculopathy (CAV)., Methods: Fifteen consecutive patients, 1 to 4 years after transplant with no angiographic evidence of CAV, underwent successful OCT imaging using the Fourier-domain OCT system (C7-XR, St. Jude Medical, St. Paul, MN) in the left anterior descending artery. Analysis included measurements of the lumen, intima, and media layers, and characterization of atherosclerotic plaques. Patients were stratified by intima-to-media (I/M) ratio and classified as normal (≤1) or abnormal (>1)., Results: Patients were a mean of 2.8 years after transplant, 58 years old, and 92% were men. OCT imaging revealed 8 of 15 patients had intimal hyperplasia with an I/M ratio >1. Comparing those with I/M ratio of ≤1 and >1, the median (interquartile range) intimal thickness was greater (75 [70-101] vs 206 [97-269]μm, p = 0.03), whereas the media thickness was no different (72 [70-103] vs 94 [73-113]μm, p = 0.53). In addition, 7 of 15 patients had lipid-rich or calcified atherosclerotic plaques., Conclusions: OCT provides high-resolution quantitative imaging of the coronary arteries and its use allows for detailed assessment of the coronary artery wall and early morphologic changes that occur after cardiac transplantation. The clinical predictive value of these OCT-derived measurements remains to be determined., (Copyright © 2013 International Society for Heart and Lung Transplantation. Published by Elsevier Inc. All rights reserved.)

Objectives: We compared intravascular ultrasound (IVUS) and 2 different generations of optical coherence tomography (OCT)-time-domain OCT (TD-OCT) and frequency-domain OCT (FD-OCT)-for the assessment of coronary disease and percutaneous coronary intervention (PCI) using stents., Background: OCT is a promising light-based intravascular imaging modality with higher resolution than IVUS. However, the paucity of data on OCT image quantification has limited its application in clinical practice., Methods: A total of 227 matched OCT and IVUS pull backs were studied. One hundred FD-OCT and IVUS pull backs in nonstented (n = 56) and stented (n = 44) vessels were compared. Additionally, 127 matched TD-OCT and IVUS images were compared in stented vessels., Results: FD-OCT depicted more severe native coronary disease than IVUS; minimal lumen area (MLA) was 2.33 ± 1.56 mm(2) versus 3.32 ± 1.92 mm(2), respectively (p < 0.001). Reference vessel dimensions were equivalent between FD-OCT and IVUS in both native and stented coronaries, but TD-OCT detected smaller reference lumen size compared with IVUS. Immediately post-PCI, in-stent MLAs were similar between FD-OCT and IVUS, but at follow-up, both FD-OCT and TD-OCT detected smaller MLAs than did IVUS, likely due to better detection of neointimal hyperplasia (NIH). Post-PCI malapposition and tissue prolapse were more frequently identified by FD-OCT., Conclusions: FD-OCT generates similar reference lumen dimensions but higher degrees of disease severity and NIH, as well as better detection of malapposition and tissue prolapse compared with IVUS. First-generation TD-OCT was associated with smaller reference vessel dimensions compared with IVUS., (Copyright © 2013 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.)

Objectives: To determine the incremental benefit of assessing myocardial perfusion defects (MPD) for acute coronary syndromes (ACS) over coronary and functional assessment by rest cardiac computed tomography (CT) in patients with acute chest pain., Background: Assessment of myocardial perfusion is feasible with cardiac CT; however, the diagnostic value of this assessment in patients at risk for ACS has not been demonstrated., Methods: The study included patients who presented to the emergency department with acute chest pain, nonischemic initial electrocardiogram (ECG), and negative cardiac biomarkers but had clinical suspicion for ACS and underwent invasive coronary angiography (ICA). Results were blinded to caregivers and patients. CT data sets were independently assessed for the presence of coronary plaque and stenosis, regional left ventricular function, and myocardial perfusion deficits by 2 blinded observers. Coronary angiography was assessed for the presence of stenosis, TIMI myocardial perfusion grade, and corrected TIMI frame count. The endpoint was ACS during index hospitalization., Results: We analyzed data from 35 subjects (69% male, mean age 58 ± 9 years) of whom 22 (63%) had ACS. The sensitivity and specificity of MPD for ACS were 86% (95% CI: 64%-96%) and 62% (95% CI: 32%-85%), respectively. Combined, MPD and RWMA assessment resulted in specificity and sensitivity of 86% (95% CI: 64%-96%) and 85% (95% CI: 54%-97%), respectively. Adding MPD and RWMA to the assessment for significant stenosis (>50%) resulted in a higher sensitivity of 91% (69-98%) and specificity of 85% (54-97%) and a significantly increased overall diagnostic accuracy when compared with assessment for stenosis (AUC: 0.88 vs 0.79; respectively, P = 0.02). Diagnostic accuracy of CT was not associated with impaired CTFC >40 or myocardial TIMI perfusion grade < 3., Conclusions: Assessment of myocardial perfusion and regional wall motion abnormalities may enhance the ability of CT to detect ACS in patients with acute chest pain., (Copyright © 2011 Society of Cardiovascular Computed Tomography. Published by Elsevier Inc. All rights reserved.)

Objectives: We designed a randomized trial exploiting optical coherence tomography (OCT) to assess coverage and apposition of overlapping bare-metal stents (BMS) and drug-eluting stents (DES) in human coronary arteries., Background: Overlapping DES impair healing in animals. Optical coherence tomography allows accurate in vivo assessment of stent strut coverage and apposition., Methods: Seventy-seven patients with long coronary stenoses were randomized to overlapping sirolimus-eluting stents (SES), paclitaxel-eluting stents (PES), zotarolimus-eluting stents (ZES), or BMS. The primary goal of the study was to determine the rate of uncovered/malapposed struts in overlap versus nonoverlap segments, according to stent type, at 6-month follow-up with OCT., Results: A total of 53,047 struts were analyzed. The rate of uncovered/malapposed struts was 1.5 +/- 3.4% and 0.6 +/- 2.7% in overlap versus nonoverlap BMS (p = NS), respectively, and 4.3 +/- 11% and 3.6 +/- 8% in overlap versus nonoverlap DES (p = NS), respectively. There were no differences in the rates of uncovered/malapposed struts between overlapping BMS and DES, likely due to low frequency of uncovered/malapposed struts in ZES (0.1 +/- 0.4%), which offset the higher rates observed in SES (6.7 +/- 9.6%) and PES (6.7 +/- 16.5%, p < 0.05). Overlap segments showed greater neointimal volume obstruction versus nonoverlap segments in all DES (p < 0.05 for all DES types). Strut-level neointimal thickness at overlap and nonoverlap segments were lowest in SES (0.16 +/- 0.1 mm and 0.12 +/- 0.1 mm, respectively) compared with PES (0.27 +/- 0.1 mm and 0.20 +/- 0.1 mm, respectively), ZES (0.40 +/- 0.16 mm and 0.33 +/- 0.13 mm, respectively), and BMS (0.55 +/- 0.31 mm and 0.53 +/- 0.25 mm, respectively, p < 0.05)., Conclusions: As assessed by OCT the impact of DES on vascular healing was similar at overlapping and nonoverlapping sites. However, strut malapposition, coverage pattern, and neointimal hyperplasia differ significantly according to DES type. (Optical Coherence Tomography for Drug Eluting Stent Safety [ODESSA]; NCT00693030)., (Copyright 2010 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.)

Cardiovascular optical coherence tomography (OCT) is a catheter-based invasive imaging system. Using light rather than ultrasound, OCT produces high-resolution in vivo images of coronary arteries and deployed stents. This comprehensive review will assist practicing interventional cardiologists in understanding the technical aspects of OCT based upon the physics of light and will also highlight the emerging research and clinical applications of OCT. Semi-automated imaging analyses of OCT systems permit accurate measurements of luminal architecture and provide insights regarding stent apposition, overlap, neointimal thickening, and, in the case of bioabsorbable stents, information regarding the time course of stent dissolution. The advantages and limitations of this new imaging modality will be discussed with emphasis on key physical and technical aspects of intracoronary image acquisition, current applications, definitions, pitfalls, and future directions.

Extrinsic compression of the left main coronary artery (LMCA) can occur in patients with severe pulmonary hypertension and enlarged pulmonary artery trunk. It has been usually described in the setting of congenital defects such as atrial septal defect, ventricular septal defect, and, more rarely, isolated persistent ductus arteriosus. Functional and structural evaluation of such patients can currently be performed noninvasively with the use of cardiac CT scanning and/or MRI. The optimal management of symptomatic patients remains unknown. We report a case of extrinsic compression of the LMCA in a symptomatic patient with Eisenmenger syndrome who underwent unprotected LMCA stent implantation. We also performed a literature review of the reported cases concerning patients treated with LMCA stent implantation for the management of this condition.

Purpose: Vulnerable plaques are characterized by a myxoid matrix, necrotic lipidic core, reactive oxygen species, and high levels of microorganisms. Aerobic microbes such as Chlamydophila pneumoniae and Mycoplasma pneumoniae usually do not survive in oxidative stress media. Archaea are anaerobic microbes with powerful anti-oxidative enzymes that allow detoxification of free radicals whose presence might favor the survival of aerobic microorganisms. We searched for archaeal organisms in vulnerable plaques, and possible associations with myxoid matrix, chlamydia, and mycoplasma bodies., Methods: Twenty-nine tissue samples from 13 coronary artherectomies from large excentric ostial or bifurcational lesions were studied using optical and electron microscopy. Infectious agents compatible with archaea, chlamydia, and mycoplasma were semiquantified using electron micrographs and correlated with the amounts of fibromuscular tissue, myxoid matrix, and foam cells, as determined from semi-thin sections. Six of the cases were also submitted to polymerase chain reaction with archaeal primers., Results: All 13 specimens showed archaeal-compatible structures and chlamydial and mycoplasmal bodies in at least 1 sample. There was a positive correlation between extent of the of myxoid matrix and archaeal bodies (r = 0.44, P = 0.02); between archaeal and mycoplasmal bodies (r = 0.41, P = 0.03), and between chlamydial bodies and foam cells (r = 0.42; P = 0.03). The PCR test was positive for archaeal DNA in 4 of the 6 fragments., Discussion: DNA and forms suggestive of archaea are present in vulnerable plaques and may have a fundamental role in the proliferation of mycoplasma and chlamydia. This seems to be the first description of apparently pathogenic archaea in human internal organ lesions.