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Background About 10% of patients admitted to a chest pain unit (CPU) exhibit atrial fibrillation (AF). Hypothesis To determine whether calcium scores (CS) are superior over common risk scores for coronary artery disease (CAD) in patients presenting with atypical chest pain, newly diagnosed AF, and intermediate pretest probability for CAD within the CPU. Methods In 73 subjects, CS was related to the following risk scores: Global Registry of Acute Coronary Events (GRACE) score, including a new model of a frequency-normalized approach; Thrombolysis In Myocardial Infarction score; European Society of Cardiology Systematic Coronary Risk Evaluation (SCORE); Framingham risk score; and Prospective Cardiovascular Munster Study score. Revascularization rates during index stay were assessed. Results Median CS was 77 (interquartile range, 1–270), with higher values in men and the left anterior descending artery. Only the modified GRACE (ρ = 0.27; P = 0.02) and the SCORE (ρ = 0.39; P < 0.005) were significantly correlated with CS, whereas the GRACE (τ = 0.21; P = 0.04) and modified GRACE (τ = 0.23; P = 0.02) scores were significantly correlated with percentile groups. Only the CS significantly discriminated between those with and without stenosis (P < 0.01). Conclusions Apart from modified GRACE score, overall correlations between risk scores and calcium burden, as well as revascularization rates during index stay, were low. By contrast, the determination of CS may be used as an additional surrogate marker in risk stratification in AF patients with intermediate pretest likelihood for CAD admitted to a CPU.

Summary Background Bioabsorbable vascular scaffolds were developed to overcome limitations of permanent bare-metal or drug-eluting coronary stents—ie, stent thrombosis (despite prolonged dual antiplatelet therapy), the life-long presence of a caged vessel segment that does not allow vasomotion or remodelling, and chronic vessel wall inflammation. We assessed the safety and performance of a new magnesium-based paclitaxel-eluting absorbable metal scaffold in symptomatic patients with de-novo coronary lesions. Methods We did a prospective, multicentre, first-in-man trial (BIOSOLVE-1) of the drug-eluting absorbable metal scaffold (DREAMS). 46 patients with 47 lesions were enrolled at five European centres. The primary endpoint was target lesion failure, a composite of cardiac death, target vessel myocardial infarction, and clinically driven target lesion revascularisation, at 6 and 12 months. Clinical follow-up was scheduled at 1, 6, 12, 24, and 36 months. Patients were consecutively assigned to angiographic and intravascular ultrasonographic follow-up at 6 months or 12 months. Optical coherence tomography was done in some patients. All patients were recommended to take dual antiplatelet therapy for at least 12 months. This trial is registered with ClinicalTrials.gov, number NCT01168830. Findings Overall device and procedural success was 100%. Two of 46 (4%) patients had target lesion failure at 6 months (both clinically driven target lesion revascularisations), which rose to three of 43 (7%) at 12 months (one periprocedural target vessel myocardial infarction occurred during angiography at the 12 month follow-up visit). We noted no cardiac death or scaffold thrombosis. Interpretation Our results show feasibility, a good safety profile, and promising clinical and angiographic performance results up to 12 months for DREAMS. Our promising clinical results show that absorbable metal scaffolds might be an alternative to polymeric absorbable scaffolds. Funding Biotronik.

Aim To analyse the timing of cardiac troponin (cTn) measurements in high-risk and cTn-positive acute coronary syndromes without persistent ST-segment elevation (NSTE-ACS) in two structurally different German chest pain units (CPUs), contrasting an urban university maximum care and a rural regional primary care facility. Methods All patients encoded as NSTEMI during the year 2013 were retrospectively enrolled in two centres: site (I)—centre of maximum care in an urban university setting and site (II)—centre of primary care in a rural regional care setting. Data acquisition included time intervals from admission to baseline cTn and first and second cTn control as well as type and timing of invasive management. Results The median times (site I vs. site II) from admission to cTn result announcement were 26.5 vs. 33.0 min (p = 0.02) for baseline, 4 vs. 4 h (p = 0.43) for the first and 11.0 vs. 16.5 h (p = 0.03) for the second control. Timely announcement, as recommended by guidelines, was available in 86.9 % at baseline, 59.4 % for the first or 41.1 % for the second cTn control. Rates and timing of invasive management were independent from the time point of positive cTn announcement (p = 0.51 and p = 0.68, respectively). Conclusions German CPUs provide timely identification of cTn-positive patients in a narrow and guideline-adherent time frame using a rapid rule-out protocol. Especially, baseline and early cTn timing was comparable between the urban university maximum care and the rural regional primary care facility without relevant impact on guideline-conforming invasive management, underlining the high standard of care in those highly professional institutions.

The aim of this study was to analyze differences in the timing of invasive management of patients with high-risk acute coronary syndrome without persistent ST-segment elevation (hr-NSTE-ACS) or myocardial infarction without persistent ST-segment elevation (NSTEMI) between on- and off-hours in a German chest pain unit (CPU). We retrospectively enrolled 160 NSTEMI patients in the study, who were admitted to two German CPUs in 2013. Patients presenting on weekdays between 8 a.m. and 6 p.m. were compared with patients presenting during off-hours. Data analysis included time intervals from admission to invasive management (goals: for hr-NSTE-ACS

If myocardial infarction remains silent, only clinical signs of complications may unveil its presence. Life-threatening complications include myocardial rupture, thrombus formation, or arterial embolization. In the presented case, a 76-year-old patient was admitted with left-sided hemiparesis. In duplex sonography, a critical stenosis of the right internal carotid artery was identified and initially but retrospectively incorrectly judged as the potential cause for ischemia. During operative thromboendarterectomy, arterial embolism of the right leg occurred coincidentally, more likely pointing towards a cardioembolic origin. Percutaneous interventions remained unsuccessful and local fibrinolysis was applied. Delayed bedside echocardiography by an experienced cardiologist demonstrated a discontinuity of the normal myocardial texture of the left ventricular apex together with an echodense, partly floating structure merely attached by a thin bridge not completely sealing the myocardial defect, accompanied by pericardial effusion. The patient was immediately transferred to emergency cardiac surgery with extirpation of the thrombus, aortocoronary bypass graft placement, and aneurysmectomy. This didactic case reveals decisive structural shortcomings in patient’s admission and triage processes and underlines, if performed timely and correctly, the value of transthoracic echocardiography as a noninvasive and cost-effective tool allowing immediate decision-making, which, in this case, led to the correct but almost fatally delayed diagnosis.

PurposeThe purpose of this paper is to present a computational framework for the simulation of patient‐specific atherosclerotic arterial walls. Such simulations provide information regarding the mechanical stress distribution inside the arterial wall and may therefore enable improved medical indications for or against medical treatment. In detail, the paper aims to provide a framework which takes into account patient‐specific geometric models obtained by in vivo measurements, as well as a fast solution strategy, giving realistic numerical results obtained in reasonable time.Design/methodology/approachA method is proposed for the construction of three‐dimensional geometrical models of atherosclerotic arteries based on intravascular ultrasound virtual histology data combined with angiographic X‐ray images, which are obtained on a routine basis in the diagnostics and medical treatment of cardiovascular diseases. These models serve as a basis for finite element simulations where a large number of unknowns need to be calculated in reasonable time. Therefore, the finite element tearing and interconnecting‐dual primal (FETI‐DP) domain decomposition method is applied, to achieve an efficient parallel solution strategy.FindingsIt is shown that three‐dimensional models of patient‐specific atherosclerotic arteries can be constructed from intravascular ultrasound virtual histology data. Furthermore, the application of the FETI‐DP domain decomposition method leads to a fast numerical framework. In a numerical example, the importance of three‐dimensional models and thereby fast solution algorithms is illustrated by showing that two‐dimensional approximations differ significantly from the 3D solution.Originality/valueThe decision for or against intravascular medical treatment of atherosclerotic arteries strongly depends on the mechanical situation of the arterial wall. The framework presented in this paper provides computer simulations of stress distributions, which therefore enable improved indications for medical methods of treatment.

To assess in a multicenter design the between-center reproducibility of volumetric virtual histology intravascular ultrasound (VH-IVUS) measurements with a semi-automated, computer-assisted contour detection system in coronary lesions that were consecutively stented. To evaluate the reproducibility of volumetric VH-IVUS measurements, experienced analysts of 4 European IVUS centers performed independent analyses (in total 8,052 cross-sectional analyses) to obtain volumetric data of 40 coronary segments (length 20.0 ± 0.3 mm) from target lesions prior to percutaneous intervention that were performed in the setting of stable (65%) or unstable angina pectoris (35%). Geometric and compositional VH-IVUS measurements were highly correlated for the different comparisons. Overall intraclass correlation for vessel, lumen, plaque volume and plaque burden was 0.99, 0.92, 0.96, and 0.83, respectively; for fibrous, fibro-lipidic, necrotic core and calcified volumes overall intraclass correlation was 0.96, 0.94, 0.98, and 0.99, respectively. Nevertheless, significant differences for both geometrical and compositional measurements were seen. Of the plaque components, fibrous tissue and necrotic core showed on average the highest measurement reproducibility. A central analysis for VH-IVUS multicenter studies of lesions prior to PCI should be pursued. Moreover, it may be problematical to pool VH-IVUS data of individual trials analyzed by independent centers. © Springer Science+Business Media, B.V. 2012.

Die Malperfusion der Aorta und ihrer Seitenaste ist eine haufige Komplikation der Aortendissektion. Die durch die akute Aortendissektion drohende Minderperfusion von Organen ist eine der Hauptursachen fur die hohe Mortalitat und Morbiditat bei diesen Patienten. Daher sind eine schnelle Diagnose, die Identifizierung der ischamiegefahrdeten Organe und die umgehende Einleitung einer Therapie zur Reperfusion erforderlich, bevor es zu bleibenden Endorganschaden kommt. Erschwert wird dies durch die haufig initial nur diskret bestehenden Symptome, die durch eine verzogerte Therapie letztendlich fatal enden konnen.

Implantation of bare metal stents (BMS) induces the release not only of particulate debris, but also of soluble vasoconstrictors which contribute to microvascular impairment. So this study aimed at addressing the potential attenuation of such vasoconstriction using paclitaxel eluting stents (PES). Using a distal protection/aspiration device, coronary arterial blood was retrieved before and during stent [n = 14 BMS, n = 14 PES, n = 3 sirolimus eluting stents (SES)] implantation in patients with saphenous vein aorto-coronary bypass stenosis and analyzed for plasma serotonin and thromboxane B(2) concentrations. The vasoconstriction of rat mesenteric arteries with intact (+E) and denuded (-E) endothelium in response to coronary arterial or aspirate plasma was quantified and normalized to that by potassium chloride (KCl(max) = 100%). Coronary arterial plasma before stent implantation induced a vasoconstriction of 30-43%, which was independent of endothelial integrity. Serotonin-release was 2.2 ± 0.5 μmol/l with BMS and 2.0 ± 0.4 μmol/l with PES, thromboxane B(2)-release was 26 ± 5 pg/ml with BMS and 22 ± 8 pg/ml with PES. BMS- and SES-aspirate plasma induced a vasoconstriction of 68 ± 18% (+E)/93 ± 14% (-E) and 81 ± 17% (+E)/124 ± 14% (-E), respectively. In contrast, PES-aspirate plasma induced only minor vasoconstriction of 8 ± 3% (+E)/12 ± 5% (-E). Addition of paclitaxel to BMS-aspirate plasma attenuated vasoconstriction. PES-aspirate induced microtubular condensation in immunofluorescence microscopy. Results indicate that aspirate from PES implantation attenuates vasoconstriction, possibly secondary to microtubular stabilization. Such acute downstream vascular paralysis could be beneficial in preventing a no-reflow phenomenon in patients undergoing stenting.

Few cases of a left atrial thrombus without mitral valve disease have been reported. We present an unusual case in which a patient presented to the emergency department with syncope and acute cerebral ischemia caused by a ball thrombus originating from the left atrium (LA). An emergency bedside echocardiogram showed the LA ball thrombus intermittently obstructing the mitral orifice and, at times, compromising the left ventricular outflow tract. This thrombus was determined to be the source of cerebral embolization resulting in acute ischemia. Surgical excision of the mass was performed. At operation, the thrombus was found to be tethered to the left atrial appendage. This tethering was not apparent on the echocardiographic images, where the thrombus appeared to be free floating. This case demonstrates the utility of transthoracic echocardiography in establishing the etiology of emergent conditions seemingly unrelated to acute cardiac disease, in this situation a neurologic presentation with syncope and cerebral ischemia.

Cardiovascular risk factors such as elevated serum lipid levels are important in the development of coronary atherosclerosis. Radiofrequency (RF) analysis of intravascular ultrasound [IVUS, Virtual histology (TM) (VH)] offers a unique tool to study the composition of coronary atherosclerotic plaque in vivo. We used data from the multicentre VH registry to assess the association between cardiovascular risk factors and coronary plaque volume and composition. Between August 2004 and July 2006, 990 patients in 42 centres were enrolled in a prospective, multicentre, non-randomized global VH registry. Coronary artery imaging was performed by conventional IVUS and RF-IVUS. The four RF-IVUS plaque components [dense calcium (DC), necrotic core (NC), fibrous (F) tissue, and fibro fatty (FF)] were analysed in every recorded frame. The results were expressed as mean cross-sectional areas, absolute volume, and percentage of total plaque volume. Risk factor assessment included evaluation of family history of previous myocardial infarction (MI), past or current smoking, diabetes mellitus, hypertension, and the laboratory measurements. Patients with diabetes had an increased relative proportion of NC (6.47 +/- 0.28 vs. 5.86 +/- 0.14%, P = 0.037) and DC (4.58 +/- 0.27 vs. 3.90 +/- 0.14%, P = 0.017), and patients with hypertension had an increased relative proportion of FF, DC (4.35 +/- 0.16 vs. 3.57 +/- 0.17%, P = 0.02) and NC (6.24 +/- 0.17 vs. 5.60 +/- 0.19%, P = 0.01). Compared with patients with LDL-C < 100 mg/dL, patients with LDL-C > 160 mg/dL had higher plaque volume (342.1 +/- 26.2 vs. 318.6 +/- 10.7 mm(3)). Linear regression analysis showed a correlation between the level of HDL-C and F (r = -0.149, P < 0.01), FF (r = -0.106, P < 0.01), and NC (r = -0.90, P < 0.05). The level of LDL correlated with F (r = 0.110, P < 0.01). Patients with prior MI have an increased percentage of F (30.03 +/- 0.59 vs. 28.20 +/- 0.37%, P = 0.009). Smoking had no relevant effect on plaque composition. Treatment with acetylsalicylacid and statins reduced FF with altering plaque volume. Radiofrequency-IVUS detects marked differences in coronary plaque composition related to the risk factor profile with particular focus on lipid levels. Greater amounts of NC were associated with diabetes, hypertension, MI, and low HDL-C. The effects of treatment of changes related to plaque composition are underway.

Zentrum fur Innere Medizin, KardiologieUniversitatsklinikum, Universitat Duisburg-Essen, 45122 Essen, Hufelandstrase 55, GermanyAtherosclerosis has become one of the most frequent causes of death in the last decades. So the analysis and improvement ofcorresponding medical treatments, e.g., balloon-angioplasty or stenting, are significant tasks in the fields of biomechanics andbiomedical engineering.One important component of the simulation of arterial walls, especially of atherosclerotically degenerated ones, is theknowledge of their anatomical and physiological composition. The intravascular ultrasound and the interpretation by the Vir-tual Histology provide cross-sectional images of the diseased arterial walls where the different components are characterizedby color-coding. The topic of this contribution is the 3D reconstruction and discretization of the artery using these color-codedimages and the biplane angiography.

BACKGROUND: Cardiac marker release after percutaneous coronary interventions (PCI) reflects myocardial necrosis which is usually the result of periprocedural (micro)embolization of atherothrombotic debris and associated with impaired left ventricular function and adverse outcome. METHODS: In this prospective study, we examined 55 patients treated by direct stenting of single de-novo lesions to assess the relationship between plaque composition, as determined by preinterventional intravascular ultrasound (IVUS) with radiofrequency data (IVUS-RF) analysis (so-called Virtual Histology) versus coronary microembolization, as determined by serial measurement of cardiac markers. IVUS was performed with an electronic system and 20-MHz IVUS catheters. Serum creatine kinase (CK) and cardiac troponin I (CTnI) were determined before PCI and after 6, 12, and 24 hours. RESULTS: Plaques had a volume of 99 +/- 63 mm(3) and were composed of fibrous (61 +/- 9%) and fibro-fatty tissue (27 +/- 12%), dense calcium (4 +/- 3%), and necrotic core (NC) (8 +/- 6%). NC volume per se, volume per 10 mm of segment length, and volume % were correlated (r = 0.64, 0.66, and 0.52 respectively; all P < 0.01) with the maximum increase in cardiac markers (CK 55.4 +/- 55.7 U/l; CTnI 0.49 +/- 0.68 ng/ml). Patients in the 4th quartile of NC volume (>10.8 mm(3)) had a particularly high increase in markers (P < 0.001). In contrast, total plaque volume and plaque components other than NC had no relation with cardiac markers (ns). CONCLUSIONS: Patients with large NC in culprit lesions may experience more myocardial injury from peri-interventional microembolization. IVUS-RF assessment before PCI has the potential to identify lesions at particular high risk which may help to tailor PCI.

Coronary stent implantation started in Germany 20 years ago. In the beginning, the progress was very slow and accelerated 10 years later. Meanwhile, coronary stent implantation is a standard procedure in interventional cardiology. From the beginning of permanent stent implantation, research started to provide temporary stenting of coronary arteries, first with catheter-based systems, later with stent-alone technology. Stents were produced from polymers or metal. The first polymer stent implantation failed except the Igaki-Tamai stent in Japan. Newly developed absorbable polymer stents seem to be very promising, as intravascular ultrasound (IVUS) and optical coherence tomography have demonstrated. Temporary metal stents were developed based on iron and magnesium. Currently, the iron stent is tested in peripheral arteries. The absorbable magnesium stent (Biotronik, Berlin, Germany) was tested in peripheral arteries below the knee and meanwhile in the multicenter international PROGRESS-AMS (Clinical Performance and Angiographic Results of Coronary Stenting with Absorbable Metal Stents) study. The first magnesium stent implantation was performed on July 30, 2004 after extended experimental testing in Essen. The magnesium stent behaved like a bare-metal stent with low recoil of 5-7%. The stent struts were absorbed when tested with IVUS. Stent struts were not visible by fluoroscopy or computed tomography (CT) as well as magnetic resonance imaging (MRI). That means, that the magnesium stent is invisible and therefore CT and MRI can be used for imaging of interventions. Only using micro-CT the stent struts were visible. The absorption process could be demonstrated in a patient 18 days after implantation due to suspected acute coronary syndrome, which was excluded. IVUS showed a nice open lumen. Stent struts were no longer visible, but replaced by tissue indicating the previous stent location. Coronary angiography after 4 months showed an ischemia-driven target lesion revascularization rate of 23.8% which was below the 30% cut point of the study protocol. No myocardial Q wave infarction or death were reported. The primary endpoint was reached. During the follow-up period, vasomotion was tested in some of the patients. The proof of principle was confirmed: restoration of vasomotion during acetylcholine testing. The development of the absorbable magnesium stent, which was pushed forward by B. Heublein, Hanover, Germany, has been successful and opens new possibilities for treatment of coronary arteries. Permanent foreign-body implantation is avoided allowing further revascularization procedures in the future, bypass grafting, and restoration of vasomotion. Even prophylactic stenting in nonsignificant stenosis, like vulnerable lesions, may become a regular procedure. Noninvasive coronary imaging by CT and MRI is now possible. Stenting of children and in peripheral arteries may become a standard procedure. Currently, the degradation process of the magnesium stent has to be prolonged, and the neointima proliferation rate has to be reduced so that the DREAM (Drug-Eluting Absorbable Magnesium Stent) concept of Ron Waksman, Washington, DC, USA, can be realized.

Summary Background Coronary stents improve immediate and late results of balloon angioplasty by tacking up dissections and preventing wall recoil. These goals are achieved within weeks after angioplasty, but with current technology stents permanently remain in the artery, with many limitations including the need for long-term antiplatelet treatment to avoid thrombosis. We report a prospective multicentre clinical trial of coronary implantations of absorbable magnesium stents. Methods We enrolled 63 patients (44 men; mean age 61·3 [SD 9·5 years]) in eight centres with single de novo lesions in a native coronary artery in a multicentre, non-randomised prospective study. Follow-up included coronary angiography and intravascular ultrasound at 4 months and clinical assessment at 6 months and 12 months. The primary endpoint was cardiac death, non-fatal myocardial infarction, or clinically driven target lesion revascularisation at 4 months Findings 71 stents, 10–15 mm in length and 3·0–3·5 mm in diameter, were successfully implanted after pre-dilatation in 63 patients. Diameter stenosis was reduced from 61·5 (SD 13·1%) to 12·6 (5·6%) with an acute gain of 1·41 mm (0·46 mm) and in-stent late loss of 1·08 mm (0·49 mm). The ischaemia-driven target lesion revascularisation rate was 23·8% after 4 months, and the overall target lesion revascularisation rate was 45% after 1 year. No myocardial infarction, subacute or late thrombosis, or death occurred. Angiography at 4 months showed an increased diameter stenosis of 48·4 (17·0%). After serial intravascular ultrasound examinations, only small remnants of the original struts were visible, well embedded into the intima. Neointimal growth and negative remodelling were the main operating mechanisms of restenosis. Interpretation This study shows that biodegradable magnesium stents can achieve an immediate angiographic result similar to the result of other metal stents and can be safely degraded after 4 months. Modifications of stent characteristics with prolonged degradation and drug elution are currently in development.

Because of the clinical benefit of lipid lowering in older patients, we hypothesized that the relation between low-density lipoprotein (LDL) cholesterol serum levels and coronary plaque progression may persist throughout aging. We analyzed serial intravascular ultrasound (IVUS) data of 60 left main stems (18 +/- 9 months apart) and evaluated the relation between LDL cholesterol levels and coronary plaque progression at different ages. The population (n = 60) was divided into 3 groups according to age: tertile 1 (n = 20) was a mean age of 48 +/- 6 years (median 51, range 33 to 55), tertile 2 (n = 20) was a mean age of 58 +/- 2 years (median 59, range 55 to 61), and tertile 3 (n = 20) was a mean age of 66 +/- 6 years (median 65, range 61 to 83). Between groups, there was no significant difference in non-age-related demographics, clinical data, lipid profiles, or medications (e.g., statins). There was a positive linear relation between LDL cholesterol and annual changes in plaque plus media area in all age tertiles, which was statistically significant in tertiles 2 and 3 (r = 0.56, p0.01; r = 0.50, p0.02) and showed a strong trend in tertile 1 (r = 0.41, p = 0.07). The estimated LDL cholesterol thresholds, which, as determined by regression analysis, would correspond to no plaque progression, were 74, 60, and 78 mg/dl, respectively, in tertiles 1, 2, and 3. In conclusion, serial IVUS data in left main coronary arteries suggest that the relation between LDL cholesterol serum levels and plaque progression persists during aging.

OBJECTIVES: We present the remodeling index (RI) versus serial intravascular ultrasound (IVUS) data. BACKGROUND: The RI, derived by comparing lesion external elastic membrane (EEM) cross-sectional area versus the reference at one time point, is used in various IVUS studies as a substitute of true remodeling (change in EEM over time), assuming that it represents true remodeling. METHODS: We studied 46 non-stenotic left main arteries using serial IVUS (follow-up 18 ± 8 months). Plaques were divided into subgroups according to the follow-up RI: follow-up RI >1 (n = 27) versus follow-up RI ≤1 (n = 19). RESULTS: Lesions with a follow-up RI >1 had an increase in lumen despite an increase in plaque because of an increase in EEM. Conversely, lesions with a follow-up RI ≤1 had a reduction in lumen as a result of both a plaque increase and EEM decrease. Overall, the follow-up RI correlated directly with changes in lesion site EEM (baseline-to-follow-up). Although there was no correlation between the follow-up RI and changes in reference EEM area, changes in reference EEM area did correlate directly with changes in lesion EEM area. In nearly 90% of lesions with a follow-up RI >1, there was a previously documented increase in EEM area. Using multivariate linear regression analysis, the follow-up RI was dependent on the baseline RI, the increase in lesion EEM area, and the decrease in reference EEM area. The follow-up RI was not dependent on changes in lesion plaque area. CONCLUSIONS: The vast majority of left main lesions with a remodeling index >1 had evidence of a previous increase in lesion-site EEM area.

Aims: The impact of right bundle branch block (RBBB) and left bundle branch block (LBBB) on myocardial perfusion is not completely understood as data are often blurred by underlying cardiac disease. The present study investigates whether conduction delays per se affect coronary perfusion-an indirect measure of myocardial oxygen demand. Methods and results: Intracoronary Doppler and ultrasound were performed in 8 patients with RBBB, 10 patients with LBBB, and 10 control subjects. All patients had angiographically normal coronary arteries and normal left ventricular function. Baseline (bAPV) and adenosine-induced hyperaemic average flow velocity and coronary flow velocity reserve (CFVR) were measured in left anterior descending arteries. Intravascular ultrasound showed no difference in lumen cross-sectional area and plaque burden between groups. Patients with RBBB and LBBB had higher bAPV values than controls (19.0 ± 4.9, 21.9 ± 5.1, and 14.6 ± 2.4 cm/s, respectively; ANOVA P = 0.003). There was no difference between patients with LBBB and RBBB compared with controls in CFVR (2.8 ± 0.5, 3.0 ± 1.0, and 3.4 ± 0.7, respectively; ANOVA P = 0.21). Conclusion: Bundle branch blocks, in particular LBBB, are associated with an increased coronary flow velocity, which indicates enhanced myocardial oxygen demand on the basis of mechanoenergetic disturbance. This may contribute to the unfavourable outcome of patients with intraventricular conduction delay.

Background: Coronary artery perforation is a rare but serious complication of percutaneous coronary interventions (PCI). Methods: We reviewed our database for cases of overt coronary perforation during PCI procedures. Hospital charts, procedural reports, and coronary angiograms of these patients were reviewed, with particular emphasis on mechanisms of perforation, management of the complication, and clinical outcome. Results: Between 01/1998 and 12/2003, a total of 19 cases (mean age: 66±8 years, 13 male) of coronary perforation occurred during 6433 PCI procedures performed within this period (incidence: 0.3%). In 12/19 (63%) cases, perforation occurred during recanalisation procedures of chronic total occlusions of coronary arteries. In all but one patient, non-surgical management was attempted: 2 out of 19 (11%) patients were treated conservatively by reversal of heparin anticoagulation. Prolonged balloon inflation at the perforation site was applied in 10/19 (53%) patients. Six (32%) patients received stents (5 of them received covered stent-grafts), 3 (16%) patients developed cardiac tamponade requiring percardiocentesis, and only 2 (11%) patients underwent bail-out surgical repair. There were 2 (11%) deaths early after the procedure. Conclusion: Coronary perforation during PCI is a rare complication, but is associated with significant morbidity and mortality. In the majority of patients, non-surgical management is both feasible and associated with a high success-rate.

Background— Intravascular ultrasound (IVUS) is increasingly used as an end point in studies aimed at reducing progression or inducing regression of coronary artery disease. However, data linking serial changes by IVUS with clinical outcomes are scarce. Methods and Results— In the absence of a validated risk score for secondary prevention, we compared 3 established risk scores for primary prevention—PROCAM, SCORE, and Framingham—with plaque progression and lumen reduction as assessed with serial IVUS (follow-up, 18±9 months) in atherosclerotic left main coronary arteries of 56 patients with established atherosclerosis. For all 3 algorithms, patients at highest estimated risk of events showed greater plaque progression than patients at lowest risk ( P r =0.41 to 0.60; P P P Conclusions— There was a positive linear relationship between the estimated risk of clinical events derived from all 3 established risk-score algorithms and the extent of plaque progression measured by serial IVUS. This translated into stenosis progression (reduction in lumen dimensions) with increasing clinical risk.

Most intravascular ultrasound (IVUS) studies of arterial remodeling in native coronary arteries reported a remodeling index obtained at a single time point. We analyzed serial IVUS examinations, including the vessel cross-sectional area changes (remodeling behavior), of 60 hemodynamically nonstenotic left main lesions (baseline vs 18.4 +/- 9.4 months follow-up). Lumen reduction resulted from vessel reduction (sometimes despite plaque + media decrease), plaque + media increase (with or without vessel increase), or both. The percent annual changes in lumen area correlated strongly with changes in vessel (r = 0.84), but not with changes in plaque + media area. Plaques were classified as group A lesions, reflecting positive remodeling behavior (vessel changes >0), or group B lesions, reflecting negative (or intermediate) remodeling behavior (vessel changes

The mechanisms of lumen enlargement during stent implantation may be significantly affected by arterial remodeling. To assess effects of lesion remodeling, we performed 3-dimensional intravascular ultrasound (IVUS) analyses in 55 coronary lesions before and after deployment of balloon-expandable stents. Standard quantitative analysis was performed, and arterial remodeling was assessed by the remodeling index (target site divided by mean of proximal and distal reference segment vessel areas), which classified lesions into group A (remodeling index ≤1, negative or intermediate remodeling, n = 40) or group B (remodeling index >1, positive remodeling, n = 15) lesions. Characteristics of the 55 patients and the interventional procedures were similar in the 2 groups. IVUS demonstrated that stenting resulted in increased lumen and vessel dimensions and in a reduced plaque size (p ≤0.001 each) in both group A and group B lesions. The extent of lumen increase inside the stents was almost identical, but resulted from different mechanisms: (1) vessel stretch was greater in group A (p

Axial plaque redistribution is an important mechanism of lumen enlargement after stenting of noncalcified lesions. To assess effects of lesion calcification on mechanisms of coronary stenting, we analyzed 55 lesions with noncircumferential calcification with 3-dimensional intravascular ultrasound (IVUS) (standard qualitative and quantitative analyses) before and after implantation of balloon-expandable stents. Thirty-two plaques (58%) showed arcs of calcium120 degrees of vessel circumference (group A), whereas 23 lesions (42%) contained arcs of calciumor =120 degrees of vessel circumference (group B). In the entire cohort of 55 lesions, as well as groups A and B, which were studied separately, both single-slice IVUS analysis (performed at minimum lumen site before intervention) and mean stented segment IVUS analysis showed an increase in lumen and vessel area and a decrease in plaque area (p0.001). The magnitude of lumen and vessel increase and of plaque decrease was similar in both groups. Group A lesions showed significant plaque extrusion into the distal reference segment that was not observed in group B (increase in plaque area of 1.3 +/- 1.9 vs 0.1 +/- 2.0 mm(2), p0.04). Stenting did not alter plaque area of the proximal reference segment in either group. In addition, there was an increase in vessel area of the distal reference of both groups, indicating that stent-induced vessel expansion observed within the lesion also affected the distal reference. Thus, longitudinal plaque redistribution and vessel expansion contribute to increased lumen dimensions during stenting of lesions with varying amounts of calcium; however, marked plaque extrusion was found only in lesions with a calcium arc of120 degrees.

I ultrasound (IVUS) permits transmural visualization of coronary arteries to assess the vessel wall, including plaque rupture sites.1–9 Three-dimensional IVUS provides volumetric data and permits deeper insights into the architecture of coronary lesions.10–12 In the present study, we assessed ruptured coronary plaques in vivo using 3-dimensional IVUS to evaluate the potential relation between the volume of the emptied plaque cavity versus lesion characteristics and dimensions. We hypothesized that rupture and ulceration of larger coronary plaques may be associated with larger dimensions of the ulcerated cavities, indicating that more material must be embolized from the core of these atheromas. • • • The study population consisted of 29 patients with symptomatic coronary artery disease who were referred to our hospital for percutaneous coronary intervention and had a ruptured coronary plaque identified by IVUS in a previously untreated coronary artery. No patient had received glycoprotein IIb/IIIa antagonists or thrombolytic therapy. Plaques had to meet the following IVUS criteria: (1) high-quality images of the entire lesion segment as well as the proximal and distal reference segments, (2) nonostial lesion location, (3) calcification that did not limit quantitative assessment of external elastic membrane cross-sectional area or volume, or no calcification, (4) absence of side branches between the lesion and the proximal and distal reference segments, and (5) absence of very angular segments on angiography to permit reliable IVUS volumetric measurements. Of 51 patients with IVUS documented plaque rupture, 29 fulfilled these criteria. The study was approved by the Local Council on Human Research. All patients signed a written informed consent form, approved by the local medical ethics committee. Cardiovascular risk factors that were recorded included diabetes mellitus (medicationdependent only), hypertension (medication-dependent only), hypercholesterolemia (medication-dependent or total serum cholesterol 200 mg/dl), a history of smoking, and a family history of coronary artery disease. All patients were on aspirin and received adequate doses of heparin intravenously. Procedures were performed by the femoral approach using standard 8Fr guiding catheters. IVUS imaging was performed after intracoronary injection of 200 g of nitroglycerin and before any coronary intervention. All IVUS studies were performed with a mechanical sector scanner (Boston Scientific Corporation, Maple Grove, Minnesota) incorporating a 30-MHz single-element beveled transducer rotating at 1,800 rpm. The transducer was withdrawn automatically using a motorized pull-back device (0.5 mm/s). All pullbacks were started as distal as possible and the entire artery was imaged to the aorto-ostial junction. In addition, the site of the plaque rupture was examined using manual interrogation; bolus injections of dye and saline were performed to confirm the presence of plaque rupture as previously described (injections were performed during manual interrogation).2,8 The examinations were recorded on 0.5-in high resolution super-VHS tape for off-line From the Department of Cardiology, Essen University, Essen, Germany; and Cardiovascular Research Foundation, New York, New York. Dr. von Birgelen’s address is: Essen University, Department of Cardiology, Center of Internal Medicine, Hufelandstr. 55, D-45122 Essen, Germany. E-mail: von.birgelen@uni-essen.de. Manuscript received December 3, 2002; revised manuscript received and accepted January 7, 2003. FIGURE 1. Longitudinal IVUS reconstruction of ruptured plaque in the mid right coronary artery. Small arrowheads in the longitudinal (A) and transversal (B) IVUS images indicate the site of the plaque rupture, which was located in the proximal (upstream) shoulder of the plaque. Large dotted arrowhead, direction of blood flow. External elastic membrane (EEM), lumen and plaque cavity (CY) area were measured on each image slice of the lesion segment (C). Thin line in (B) and (C), the plane of the longitudinal reconstruction (A).

AIMS: In order to assess the long term safety, clinical performance and the bioabsorption process of the paclitaxel-pluting absorbable magnesium scaffold (DREAMS) 3-year clinical data and multi-modality imaging outcomes are reported. METHODS AND RESULTS: Forty-six subjects were enrolled in the first-in-man BIOSOLVE-I study in two different cohorts with clinical follow-up at 1, 6, 12, 24 and 36 months; angiographic and IVUS follow-up for cohort 1 at 6-month and for cohort 2 at 12-month. A subgroup of patients underwent OCT and vasomotion testing. The primary endpoint is Target Lesion Failure (TLF) at 6-month for cohort 1 and at 12-month for cohort 2. For some patients also 18-month and 24-month imaging data are available.TLF rate at 36-month was 6.8% including 2 TLRs and 1 peri-procedural MI occurring at the 12-month follow-up angiography; no events emerged from 12- to 36-month. No cardiac death or scaffold thrombosis was observed. Vasoconstriction after acetylcholine at 6-month (delta=-10.04%; p=0.0008 versus baseline) followed by vasodilatation after nitroglycerine (delta=8.69%; p Echogenicity data using the decrease in intensity of the ultrasound signal to quantify the change in strut structure demonstrate a continuous decrease in % hyperechogenicity over the follow-up period, with the most pronounced changes within the first 6 months (22 to 16% p CONCLUSIONS: DREAMS shows excellent safety and efficacy data with no death and no scaffold thrombosis up to 3 years in the BIOSOLVE-I trial. Multi-modality imaging documented the absorption process and the uncaging aspect of this device already at 6 months.

In order to assess the long term safety, clinical performance and the bioabsorption process of the paclitaxel-eluting absorbable magnesium Scaffold (DREAMS) 3-year clinical data and multi-modality imaging outcomes are reported. Forty-six subjects were enrolled in the first-in-man BIOSOLVE-I study

Background— The drug-eluting absorbable metal scaffold has demonstrated feasibility, safety, and promising clinical and angiographic outcomes at 12 months in human coronary arteries. This study aimed to evaluate the degradation rate and long-term vascular responses to drug-eluting absorbable metal scaffold. Methods and Results— BIOSOLVE-I was a multicenter, single-arm, first-in-man trial assessing the safety and performance of drug-eluting absorbable metal scaffold in 46 patients with coronary artery disease. Patients who underwent serial invasive imaging, such as quantitative coronary angiography, intravascular ultrasound, and optical coherence tomography, at 6 and 12 months were included in this study. From postimplantation to follow-up, arterial curvature and angulation were significantly increased by the degradation process. The greatest increase was seen from postimplantation to 6 months. The systolic–diastolic changes of the curvature and angulation gradually improved throughout the follow-up period. At the site of implantation, vasoconstriction (−10% mean reduction) was observed during the acetylcholine test at 6 months. The average percent hyperechogenicity of the scaffolded segments showed a continuous decrease over time, with the most pronounced changes within the first 6 months (from 22.1±7.0% to 15.8±3.7%; P 2 ; P =0.794) remained unchanged from 6 to 12 months. Conclusions— This serial analysis of drug-eluting absorbable metal scaffold confirmed the safety and efficacy of this new device, with vasomotion restoration and continued degradation over time demonstrated by multi-invasive imaging modalities. Clinical Trial Registration— URL: http://www.clinicaltrials.gov . Unique identifier: NCT01168830.

In this paper, we consider the elastic deformation of arterial walls as occurring, e.g., in the process of a balloon angioplasty, a common treatment in the case of atherosclerosis. Soft biological tissue is an almost incompressible material. To account for this property in finite element simulations commonly used free energy functions contain terms penalizing volumetric changes. The incorporation of such penalty terms can, unfortunately, spoil the convergence of the nonlinear iteration scheme, i.e., of Newton’s method, as well as of iterative solvers applied for the solution of the linearized systems of equations. We show that the augmented Lagrange method can improve the convergence of the linear and nonlinear iteration schemes while, at the same time, implementing a guaranteed bound for the volumetric change. Our finite element model of an atherosclerotic arterial segment, see Fig. 1, is constructed from intravascular ultrasound images; for details see [4].

Atherosclerotic coronary arteries are more calcified in patients with than without chronic kidney disease (CKD). We addressed the potential for coronary microvascular obstruction in patients with and without CKD during stenting for saphenous vein aorto-coronary graft (SVG) stenosis under protection with a distal occlusion/aspiration device. In patients with and without CKD (n = 20/20), SVG plaque composition was analyzed from virtual histology using intravascular ultrasound analysis before stent implantation. There was more dense calcium and more necrotic core in patients with than without CKD (14 ± 3 vs. 3 ± 1 % and 21 ± 3 vs. 12 ± 2 % of plaque volume, respectively). Coronary aspirate was retrieved during stent implantation and divided into particulate debris and plasma. Patients with CKD had more particulate debris and calcium release than patients without CKD. In contrast, the release of serotonin was less in patients with than without CKD (0.4 ± 0.1 vs. 1.2 ± 0.3 μmol/L), whereas that of catecholamines, endothelin, tissue factor, thromboxane, tumor necrosis factor α, and C reactive protein was not significantly different. Confirming the biochemical results, aspirate plasma from patients with CKD induced less vasoconstriction of rat mesenteric arteries than that from patients without CKD (with endothelium (+E), 26 ± 7 %; without endothelium (−E): 28 ± 7 % vs. +E, 68 ± 12 %; −E: 95 ± 16 % of maximum KCl-induced vasoconstriction). Graft atherosclerosis of patients with CKD is more degenerated and releases more particulate debris and calcium, but the aspirate has surprisingly less serotonin and vasoconstrictor potential.

Neointimal hyperplasia is one of the key components of the restenotic process. The aim of this study was to evaluate the efficacy and safety of a microbubble delivery of c-myc antisense peptide in reducing restenosis after coronary stenting in de novo stenosis with intravascular ultrasound. A Multi-Link Zeta bare metal stent was implanted in de novo coronary artery lesions (RD ≥ 2.5- ≤ 4.0 mm; TL ≥ 15- ≤ 30 mm in length). Serial intravascular ultrasound analyses were performed in 25 lesions. A dose of 16mg RESTEN-MPTM (AVI BioPharma supplied by Global Therapeutics LLC) was intravenously administered after stenting and again 24 hours later. In three centres in Germany a total of 50patients (51 lesions) were enrolled, 34 in Essen, 13 in Coburg and 3 in Heidelberg. Before stenting, the minimal lumen diameter (MLD) and length of stenosis were determined. 84% (43/51) of the lesions were either Type B2 or C lesions. At six-month follow-up, angiography was performed. Generally the neointimal proliferation was minor. Major adverse cardiac events (MACE) were 10.0% after 6 months and 21.9% after 12 months. The target lesion revascularization was 15.6%, the target vessel revascularization 18.8% after 12 months. Of the 34 patients studied at six-months in the IVUS sub-study, six patients required target lesion revascularization (TLR). Binary restenosis rate by intravascular ultrasound was 26 ± 4%. Generally the neointima proliferation was minor and open vessel lumen could be demonstrated during follow-up. Microbubble delivery of c-myc antisense seems to be effective in reducing neointimal tissue proliferation without the problem of late stent thrombosis. Neointima proliferation seems to be attenuated but not eliminated. MACE was not increased in this study population.

The interventional implantation of a stent into an atherosclerotic coronary artery is a unique and paradigmatic scenario of plaque rupture in humans. The use of protection devices not only prevents the released plaque particles and the superimposed thrombotic material from being washed and embolized into the coronary microcirculation of the individual patient, but permits also the retrieval and ex vivo analysis of particulate plaque debris and soluble substances. The particulate debris comprises typical cholesterol crystals, foam cells, hyalin material and calcium deposits from the atheroma as well as platelets and coagulation material; soluble substances include vasoconstrictors, such as serotonin and thromboxane, as well as inflammatory mediators, such as TNFα which amplifies vasoconstriction by inducing endothelial dysfunction. The vasoconstriction observed in a bioassay ex vivo correlates to clinical symptoms, angiographic stenosis and plaque burden, as assessed by intravascular ultrasound. The release of TNFα into the aspirate correlates to restenosis. Detailed analysis of the human coronary aspirate may promote a better understanding of the pathophysiology of the vulnerable atherosclerotic plaque and help to better antagonize the microvascular consequences of coronary microembolization, including the no reflow phenomenon. This article is part of a Special Issue entitled "Coronary Blood Flow."

Rationale: Stent implantation into atherosclerotic plaques releases, apart from particulate debris, soluble substances that contribute to impaired microvascular perfusion. Objective: To quantify the release of vasoconstrictors and to determine the efficacy of coronary dilators to attenuate their action. Methods and Results: Using a distal protection/aspiration device, coronary arterial blood was retrieved before and during stenting in 22 patients with severe saphenous vein aorto-coronary bypass stenoses. The release of catecholamines, endothelin, serotonin, thromboxane B 2 , and tumor necrosis factor (TNF)α was measured. The response of rat mesenteric arteries with intact (+E) and denuded (−E) endothelium to aspirate plasma was normalized to that by KCl. Responses to selective receptor blockade, adenosine, nitroprusside, and verapamil against the aspirate-induced constriction were determined. The coronary arterial plasma withdrawn before stenting induced 21±5% and the aspirate plasma after stenting induced 95±8% of maximum KCl-induced vasoconstriction. Serotonin, thromboxane B 2 , and TNFα release into aspirate plasma increased by 1.9±0.2 μmol/L, 25.6±3.1 pg/mL, and 19.7±6.1 pg/mL, respectively, during stenting. The aspirate-induced vasoconstriction was largely antagonized by selective serotonin receptor blockade, with little further antagonism by additional thromboxane receptor blockade. TNFα did not induce constriction per se but potentiated the constriction with serotonin and the thromboxane-analog U-46619 in arteries +E. The concentrations to induce half-maximal vasodilation were comparable for nitroprusside (+E, 3.3×10 −8 ; −E, 1.9×10 −8 mol/L) and verapamil (+E, 8.3×10 −8 ; −E, 7.8×10 −8 mol/L), and the vasoconstriction was eventually eliminated. The vasodilator response to adenosine was dependent on functional endothelium and weaker. Conclusion: Serotonin is the main coronary vasoconstrictor after stenting, and thromboxane and TNFα somewhat potentiate the serotonin response. Nitroprusside and verapamil are more potent than adenosine to attenuate the aspirate plasma-induced vasoconstriction, and they are not dependent on functional endothelium.

Udgivelsesdato: 2010-Apr AIMS: To assess for the first time in a multicentre design the between-centre reproducibility of volumetric virtual histology intravascular ultrasound (VH-IVUS) measurements with a semi-automated, computerassisted contour detection system in mild-to-moderately diseased coronary segments. METHODS AND RESULTS: Analysts of four European IVUS centres performed independent IVUS analyses (in total 7,188 cross-sectional analyses) and obtained volumetric data to evaluate the reproducibility of volumetric VH-IVUS measurements in 36 coronary segments (length 20.0+/-0.4 mm) from patients with stable angina. Geometric and compositional VH-IVUS measurements were highly correlated for the different comparisons. Overall intraclass correlation for vessel, lumen, plaque volume and plaque burden were 0.98, 0.92 0.95, and 0.86, respectively; for fibrous, fibro-lipidic, necrotic core and calcified volumes overall intraclass correlations were 0.95, 0.93, 0.99, and 1.00, respectively. There were significant but small differences for vessel, lumen, fibrous and calcified volumes, and there was no significant difference for plaque volume. Of the plaque components necrotic core and calcified volume showed on average the highest reproducibility. CONCLUSIONS: These findings underline the necessity to centrally analyse IVUS data obtained in multicentre studies addressing mild-to-moderately diseased coronary arteries. In addition, pooling VH-IVUS data from different studies, analysed at different centres, may be problematical.

Coronary microembolization from the erosion or rupture of a vulnerable atherosclerotic plaque occurs spontaneously in acute coronary syndromes and iatrogenically during percutaneous coronary interventions. Typical consequences of coronary microembolization are microinfarcts with an inflammatory response, contractile dysfunction, and reduced coronary reserve. Apart from transient elevations of creatine kinase and troponin, microemboli can be visualized by intracoronary Doppler and the resulting microinfarcts by late-enhancement nuclear magnetic resonance. Statins, antiplatelet agents, and coronary vasodilators protect against microembolization and microinfarction when started before percutaneous coronary interventions. Distal protection devices can retrieve atherothrombotic debris and prevent its embolization into the microcirculation, but their effect on clinical outcome has been disappointing so far, except for saphenous vein bypass grafts. Devices for aspiration of thrombi and thrombus-derived vasoconstrictor, thrombogenic, and inflammatory substances, however, reduce thrombus burden, improve perfusion, and provide protection in patients with acute myocardial infarction.

Percutaneous transcatheter aortic valve implantation (TAVI) is an evolving interventional therapy for high-risk, non-surgical patients with severe, symptomatic aortic valve stenosis (AS). As a standard procedure, 2D transesophageal echocardiography has been used for the preinterventional assessment of the native valve and measurement of the aortic annulus as well as for intraprocedural guidance. Recently, a new matrix array, transesophageal probe for real-time three-dimensional echocardiography (RT3D-TEE) has been introduced. We applied this new technique to monitor percutaneous aortic valve implantation and described our initial experiences with this method in patients undergoing TAVI. We hypothesized that RT3D-TEE provides improved evaluation of the native aortic valve and annulus dimension due to unlimited scan plane orientation. This new technology should also enable accurate guiding of percutaneous cardiac interventions by providing immediate information on prosthesis position and function in real-time. In our preliminary clinical experience real-time three-dimensional transesophageal echocardiography (RT3D TEE) was demonstrated to provide improved guiding of percutaneous aortic valve replacement by superior spatial visualisation of the cardiac structures and facilitated the detection of procedure-related complications. Due to the advantages of real-time 3D TEE monitoring, this technique might improve the outcome of patients treated with percutaneous aortic valve replacement.

Background: Although the use of drug-eluting stents has been shown to limit neointimal hyperplasia, currently available DES may adversely affect re-endothelialization, possibly precipitating late cardiac events. The aim of this study was to evaluate the efficacy and safety of a microbubble delivery of c-myc antisense peptide in preventing restenosis after coronary stenting in de novo stenosis with intravascular ultrasound. Methods: A BMS was implanted in de novo coronary artery lesions (RD ≥ 2.5- ≤4.0mm; TL ≥ 15- ≤ 30mm in length). Serial intravascular ultrasound analysis were performed in 25 lesions. A dose of 16mg RESTEN-MPTM (AVI BioPharma/Global Therapeutics LLC) was intravenously administered after stenting and again 24 hours later. Results: A total of 50 patients were enrolled, 34 in Essen, 13 in Coburg and 3 in Heidelberg. Before stenting, the MLD and length of stenosis was determined by QCA. 18 Patients had a LAD lesion, 21 LCX, 12 RCA. 84% (43/51) of the lesions were either Type B2 or C lesions. At six month follow-up, angiography with a QCA was performed. Generally the neointimal proliferation was minor and open vessel lumen could be demonstrated during follow-up. Of the 30 patients currently studied at six-months in the IVUS sub-study, six patients required TLR. Late lumen loss by QCA was 0.47±0.09mm. Volume stenosis by IVUS was 26 ± 4 %. Generally the neointima proliferation was minor and open vessel lumen could be demonstrated during follow-up. Summary: Microbubble delivery of c-myc antisense seems to be effective in reducing neointimal tissue proliferation without the problem of late stent thrombosis, because the proliferation seems to be attenuated but not fully blocked.

Background: Cardiovascular risk factors have an impact on coronary atherosclerosis evolution. However, there is only limited information about the relationship between risk and atherosclerotic plaque as measured invasively by Intravascular Ultrasound Radiofrequency (IVUS-RF) analysis. The Aim of this study was to assess the impact of cardiovascular risk factors not only on overall coronary plaque volume but on coronary plaque composition. Methods: 990 patients from 42 centers were enrolled in the prospective, multicenter, non randomized, global VH-IVUS registry. Coronary lesions were measured by conventional and IVUS-VH parameters using 20MHz Intravascular Ultrasound catheter. The four IVUS-VH plaque components (Dense Calcium-DC, Necrotic Core-NC, Fibrous tissue-F, Fibro Fatty-FF) were analyzed in every recorded frame. The results were expressed as mean cross-sectional areas, and percentage of total plaque volume. Risk factor assessment included correlation with family history of myocardial infarction, past or current smoking, diabetes mellitus, hypertension, and laboratory measurements. Results: Patients with diabetes have an increased relative amount of NC (6.47±0.28% vs. 5.86±0.14%, p=0.037) and DC (4.58±0.27% vs. 3.90±0.14%, p=0.017), Patients with hypertension have an increased relative amount of FF, DC (4.35±0.16% vs. 3.57±0.17%, p=0.02) and NC (6.24±0.17% vs. 5.60±0.19%, p=0.01). Compared with patients with LDL cholesterol 160 mg/dl had higher plaque volume (342.1±26.2mm 3 vs. 318.6±10.7mm 3 ). Linear Regression Analysis showed a correlation between the level of HDL and F (r=−0.149, p Conclusion: IVUS-RF analysis detects marked differences in coronary plaque depending on the risk factor profile with particular focus on lipid levels. Patients with greater amounts of necrotic core were associated with hypertension, myocardial infarction, and low HDL. This may have implications for prognosis and systemic treatment of patients with coronary artery disease.

Coronary stent implantation started in Germany 20 years ago. In the beginning, the progress was very slow and accelerated 10 years later. Meanwhile, coronary stent implantation is a standard procedure in interventional cardiology. From the beginning of permanent stent implantation, research started to provide temporary stenting of coronary arteries, first with catheter-based systems, later with stent-alone technology. Stents were produced from polymers or metal. The first polymer stent implantation failed except the Igaki-Tamai stent in Japan. Newly developed absorbable polymer stents seem to be very promising, as intravascular ultrasound (IVUS) and optical coherence tomography have demonstrated. Temporary metal stents were developed based on iron and magnesium. Currently, the iron stent is tested in peripheral arteries. The absorbable magnesium stent (Biotronik, Berlin, Germany) was tested in peripheral arteries below the knee and meanwhile in the multicenter international PROGRESS-AMS (Clinical Performance and Angiographic Results of Coronary Stenting with Absorbable Metal Stents) study. The first magnesium stent implantation was performed on July 30, 2004 after extended experimental testing in Essen. The magnesium stent behaved like a bare-metal stent with low recoil of 5-7%. The stent struts were absorbed when tested with IVUS. Stent struts were not visible by fluoroscopy or computed tomography (CT) as well as magnetic resonance imaging (MRI). That means, that the magnesium stent is invisible and therefore CT and MRI can be used for imaging of interventions. Only using micro-CT the stent struts were visible. The absorption process could be demonstrated in a patient 18 days after implantation due to suspected acute coronary syndrome, which was excluded. IVUS showed a nice open lumen. Stent struts were no longer visible, but replaced by tissue indicating the previous stent location. Coronary angiography after 4 months showed an ischemia-driven target lesion revascularization rate of 23.8% which was below the 30% cut point of the study protocol. No myocardial Q wave infarction or death were reported. The primary endpoint was reached. During the follow-up period, vasomotion was tested in some of the patients. The proof of principle was confirmed: restoration of vasomotion during acetylcholine testing. The development of the absorbable magnesium stent, which was pushed forward by B. Heublein, Hanover, Germany, has been successful and opens new possibilities for treatment of coronary arteries. Permanent foreign-body implantation is avoided allowing further revascularization procedures in the future, bypass grafting, and restoration of vasomotion. Even prophylactic stenting in nonsignificant stenosis, like vulnerable lesions, may become a regular procedure. Noninvasive coronary imaging by CT and MRI is now possible. Stenting of children and in peripheral arteries may become a standard procedure. Currently, the degradation process of the magnesium stent has to be prolonged, and the neointima proliferation rate has to be reduced so that the DREAM (Drug-Eluting Absorbable Magnesium Stent) concept of Ron Waksman, Washington, DC, USA, can be realized.

In recent years, intravascular ultrasound (IVUS) has evolved as an important adjunct to angiography, providing insights that are significantly altering conventional paradigms in diagnosis and therapy. However, major drawbacks in the use of IVUS relied on the fact that a heavy console had to be moved from lab to lab, and extensive time for set up and image analysis. This additional time and the decrease in patients' through-put has not been applicable in clinical practice for many labs. Our manuscript concerns a novel PC-based platform for IVUS that enables the online intergration of digital intracoronary ultrasound images into angiographic images. This new technique offers remote operation, multiple control devices and custom viewing options. The PC-based platform enables IVUS images to be viewed simultaneously from multiple vantage points in the lab, and allows for multiple user interfaces.

The reduction in plaque volume during stent implantation is associated with the release of particulate debris and plaque-derived soluble substances. We studied the potential release of the proinflammatory cytokine TNF-α into the coronary circulation and whether such release is related to the reduction in plaque volume and, possibly, a predictor for restenosis. In 18 male patients ( n = 24 stents) with severe stenosis in a saphenous vein aortocoronary bypass graft (SVG), we used a distal balloon occlusion-aspiration device during stent implantation. The aspirate TNF-α levels were determined before and after stent implantation and related to the angiographic and intravascular ultrasound-assessed severity of stenosis and restenosis. We found that TNF-α is, indeed, released into the aspirate of stented SVG (9 ± 1 and 28 ± 3 pg/ml before and after stent implantation, respectively, P < 0.0001) and that such release is related to the reduction in plaque volume ( r = 0.88, P < 0.0001) and associated with restenosis after 5 mo ( r = 0.71, P = 0.001). The periprocedural release of plaque-derived TNF-α possibly represents the amount and activity of the atherosclerotic process and might be a predictor for restenosis.

Background An asymptomatic and apparently healthy 64-year-old marathon runner underwent comprehensive cardiovascular risk assessment as part of a prospective study on calcified coronary plaque burden in master marathon runners. His profile suggested a low 10-year cardiovascular risk. Investigations Conventional risk-factor assessment, coronary artery calcium quantification, bicycle stress test, echocardiography, coronary angiography, intravascular ultrasonography, including virtual histology, and intracoronary Doppler ultrasonography. Diagnosis Severe coronary atherosclerosis of the left anterior descending, mid left circumflex, and left main arteries. Management Stenting of the left anterior descending artery, CABG surgery, and intensive risk-factor modification. The patient was also advised against participating in future marathon competitions.

A 54-year-old male patient with known 2-vessel coronary artery disease and stable angina presented for elective percutaneous coronary intervention of a proximal right coronary artery stenosis (Figure 1). Previously, the patient had undergone intervention of mid-left anterior descending coronary artery stenosis by sirolimus-eluting stent implantation. Figure 1. Preinterventional coronary angiogram showing the high-grade stenosis in the proximal segment of the right coronary …

Positive remodeling is more often observed in lesions of patients who have acute coronary syndromes or vulnerable (rupture-prone) plaques. However, there are few data that correlate plaque morphology, composition, and arterial remodeling in vivo. We evaluated coronary plaque characterization of lesions with positive remodeling using intravascular ultrasound (IVUS) radiofrequency data analysis. Seventy-seven nonbifurcation native coronary lesions (in 50 patients) were imaged in vivo using 30-MHz IVUS transducers. Lesions were classified into 4 plaque types, fibrous, fibrofatty, dense calcium, and necrotic core, by using processing of the radiofrequency signal validated in vitro. The remodeling index was calculated as the lesion external elastic membrane area divided by the proximal reference external elastic membrane area. Lesions were divided into 2 groups: positive remodeling (remodeling index >1.0, 26 lesions) and intermediate/negative remodeling (remodeling index