Assessment of coronary arterial plaque by optical coherence tomography

The purpose of this study was to analyze the ability of optical coherence tomography (OCT) to identify coronary arterial plaque diagnosed by histologic examination. We examined 166 sections from 108 coronary arterial segments of 40 consecutive human cadavers (24 men and 16 women; mean age 74 +/- 7 years). The plaque type was classified as fibrous (n = 43), fibrocalcific (n = 82), or lipid-rich (n = 41). The accuracy of OCT and intravascular ultrasound (IVUS) in characterizing the plaque type was studied, with the histologic consensus diagnosis serving as the gold standard. OCT, as well as IVUS, had high sensitivity and specificity for characterizing the different types of atherosclerotic plaque. OCT had a higher sensitivity for characterizing lipid-rich plaques than IVUS (85% vs 59%, p = 0.03). In conclusion, the high resolution of OCT permitted evaluation of lipid-rich plaques more accurately than IVUS.

Morphological and morphometric analysis of coronary atherosclerosis--an autopsy study

Coronary atherosclerosis is the most frequent cause of ischemic heart disease. The composition and vulnerability of the atherosclerotic plaque determines the development of acute coronary syndromes. In this study, 224 advanced atherosclerotic plaques were identified from the main coronary arterial branches of 10 autopsy heart specimens. The plaques were classified by American heart association (AHA) and modified American heart association classification. Vulnerability of the plaques and factors influencing vulnerability were assessed. Vulnerable plaques were mostly of Type IV category of AHA classification and of thin cap fibroatheroma type by modified American heart association classification. Inflammation was more frequent and was of a higher grade in vulnerable plaques. Calcification was predominantly of mild grade.

Coronary artery bypass graft surgery in New Zealand's Auckland region: a comparison between the clinical priority assessment criteria score and the actual clinical priority assigned

AIMS

To describe the cohort of patients waiting for Coronary Artery Bypass Graft (CABG) surgery in the Auckland region; compare the Clinical Priority Assessment Criteria (CPAC) score with the actual priority assigned; and to assess the impact of a patient's demographic characteristics on the CPAC score and the assigned priority.

METHODS

An electronic register was developed to capture all patients who had a CPAC form completed for isolated CABG surgery during the period June 2002 to September 2004 in the Auckland region. CPAC scores and clinical priority assigned were collected from the CABG booking form. Demographic characteristics came from the booking form (age, gender) or linkage via the National Health Index (NHI) number (ethnicity, deprivation score).

RESULTS

The cohort displayed severe coronary artery disease and symptoms: 70% had class 3 or class 4 angina; 89% had their ability to work, live independently, or care for dependents threatened; 65% had three-vessel coronary disease; and 26% had left-main coronary disease. The CPAC score correlated only modestly with the actual clinical priority assigned, with an extremely wide range of scores for any given clinical priority. The mean CPAC score varied by the age of the patient, level of deprivation, and ethnicity--with higher mean scores among male patients who were Maori, Pacific, or more socioeconomically deprived. Clinical priority varied less by demographic characteristics than did the CPAC score, except more women than men were assigned the 'emergency' category. Despite higher CPAC scores for Maori and Pacific men, these did not translate to greater urgency in clinical priority.

CONCLUSIONS

The CPAC scoring system is used to limit access onto the CABG surgery waiting list in Auckland, but is not used to prioritise patients as to the urgency of surgery once on the list. The challenge is to determine why clinicians do not consider that the CPAC score is adequate to prioritise the urgency of surgery and to build in a process whereby any such score can be continuously evaluated and improved. We have demonstrated that the establishment of an electronic register of such patients can provide timely analysis of patterns of practice and could be used on a national scale to improve future CPAC scoring systems.

The causation of disease - the practical and ethical consequences of competing explanations

The prevention, treatment and management of disease are closely linked to how the causes of a particular disease are explained. For multi-factorial conditions, the causal explanations are inevitably complex and competing models may exist to explain the same condition. Selecting one particular causal explanation over another will carry practical and ethical consequences that are acutely relevant for health policy. In this paper our focus is two-fold; (i) the different models of causal explanation that are put forward within current scientific literature for the high and rising prevalence of the common complex conditions of coronary artery disease (CAD) and type 2 diabetes mellitus (T2D); and (ii) how these explanations are taken up (or not) within national health policy guidelines. We examine the causal explanations for these two conditions through a systematic database search of current scientific literature. By identifying different causal explanations we propose a three-tier taxonomy of the most prominent models of explanations: (i) evolutionary, (ii) lifecourse, and (iii) lifestyle and environment. We elaborate this taxonomy with a micro-level thematic analysis to illustrate how some explanations are semantically and rhetorically foregrounded over others. We then investigate the uptake of the scientific causal explanations in health policy documents with regard to the prevention and management recommendations of current National Service Frameworks for CAD and T2D. Our findings indicate a lack of congruence between the complexity and frequent overlap of causal explanations evident in the scientific literature and the predominant focus on lifestyle recommendations found in the mainstream health policy documents.

Selection of patients for myocardial perfusion scintigraphy based on fuzzy sets theory applied to clinical-epidemiological data and treadmill test results

Coronary artery disease (CAD) is a worldwide leading cause of death. The standard method for evaluating critical partial occlusions is coronary arteriography, a catheterization technique which is invasive, time consuming, and costly. There are noninvasive approaches for the early detection of CAD. The basis for the noninvasive diagnosis of CAD has been laid in a sequential analysis of the risk factors, and the results of the treadmill test and myocardial perfusion scintigraphy (MPS). Many investigators have demonstrated that the diagnostic applications of MPS are appropriate for patients who have an intermediate likelihood of disease. Although this information is useful, it is only partially utilized in clinical practice due to the difficulty to properly classify the patients. Since the seminal work of Lotfi Zadeh, fuzzy logic has been applied in numerous areas. In the present study, we proposed and tested a model to select patients for MPS based on fuzzy sets theory. A group of 1053 patients was used to develop the model and another group of 1045 patients was used to test it. Receiver operating characteristic curves were used to compare the performance of the fuzzy model against expert physician opinions, and showed that the performance of the fuzzy model was equal or superior to that of the physicians. Therefore, we conclude that the fuzzy model could be a useful tool to assist the general practitioner in the selection of patients for MPS.

Coronary artery calcium in HIV-infected men treated with highly active antiretroviral therapy

Calcium is a common component of an atherosclerotic plaque; therefore, the presence of coronary artery calcium (CAC) indicates atherosclerosis. This study investigated the difference in total CAC scores between HIV-infected patients treated with highly active antiretroviral therapy (HAART) and HIV-negative age-matched controls. HIV patients were 27 men treated with a protease inhibitor-containing HAART regimen for more than 1 year (M = 4.92 years, SD = 2.02), aged 30 to 60 years (M = 43.52 years, SD = 6.65), and not receiving lipid-lowering or hypoglycemic drugs. Controls were age-matched men randomly selected (three controls to one case, for a total of 81 controls) from our existing database of 25,250 men who self-referred for CAC screening (control database). Electron beam tomography was used to obtain CAC scores. The CAC scores were coded as above or below the age-specific (stratified in 5-year increments) 10th, 25th, 50th, 75th, or 90th percentile of our control database. Chi-square analyses for two independent samples indicated (1) a larger frequency of controls with CAC scores above the 10th (chi1= 8.32, P = .004) and 25th (chi1= 5.45, P = .02) percentiles than that of HIV patients, (2) no differences in CAC scores between groups above the 50th (chi = 0.85, P = .357) or 75th (chi = 0.46, P = .497) percentile, and (3) a larger frequency of HIV patients who were above the 90th percentile (chi = 4.5, P = .034). The strength of the relationship between group membership and scoring above the 90th percentile was significant (phi = 0.20, P = .034). These results tentatively suggest that there is an elevated level of subclinical atherosclerosis in HIV patients treated with HAART.

Fr�hdiagnostik der funktionell relevanten koronaren Herzerkrankung

In cases of stable or to a large extent symptom-free coronary heart disease (CHD) and atypical symptomatology, the indication for diagnostic cardiac catheterization is first confirmed by noninvasive diagnostics of ischemia. This can be carried out either with ergometric stress tests or imaging procedures in combination with ergometric or pharmacological stress. Myocardial scintigraphy and stress echocardiography are established techniques and to an increasing extent stress magnetic resonance imaging (MRI). In addition to sensitivity in providing evidence for ischemia, technical improvements in computed tomography (CT) and MRI have opened up new possibilities for visualizing coronary vessels and vascular wall morphology. While CT coronary angiography with its high spatial resolution is on the threshold of clinical application for selected patients, MRI has the potential for furnishing information on wall movement analysis, perfusion, coronary flow measurement, and plaque characterization to become the future cardiovascular "all-round examination".

Distinct molecular portraits of human failing hearts identified by dedicated cDNA microarrays

AIMS

This study aimed to investigate whether a molecular profiling approach should be pursued for the classification of heart failure patients.

METHODS AND RESULTS

Applying a subtraction strategy we created a cDNA library consisting of cardiac- and heart failure-relevant clones that were used to construct dedicated cDNA microarrays. We measured relative expression levels of the corresponding genes in left ventricle tissue from 17 patients (15 failing hearts and 2 nonfailing hearts). Significance analysis of microarrays was used to select 159 genes that distinguished between all patients. Two-way hierarchical clustering of the 17 patients and the 159 selected genes led to the identification of three major subgroups of patients, each with a specific molecular portrait. The two nonfailing hearts clustered closely together. Interestingly, our classification of patients based on their molecular portraits did not correspond to an identified etiological classification. Remarkably, patients with the highest medical urgency status (United Network for Organ Sharing, Status 1A) clustered together.

CONCLUSION

With this pilot feasibility study we demonstrated a novel classification of end-stage heart failure patients, which encourages further development of this approach in prospective studies on heart failure patients at earlier stages of the disease.

Quantification of human atherosclerotic plaques using spatially enhanced cluster analysis of multicontrast-weighted magnetic resonance images

One of the current limitations of magnetic resonance imaging (MRI) is the lack of an objective method to classify plaque components. Here we present a cluster analysis technique that can objectively quantify and classify MR images of atherosclerotic plaques. We obtained three-dimensional (3D) images from 12 human coronary artery specimens on a 9.4T imaging system using multicontrast-weighted fast spin-echo (T1-, proton density-, and T2-weighted) imaging with an isotropic voxel size of 39 micro. Spatially enhanced cluster analysis (SECA) was performed on multicontrast MR images, and the resulting segmentation was evaluated against histological tracings. To visualize the overall structure of plaques, the MR images were rendered in 3D. The specimens exhibited lesions of American Heart Association (AHA) plaque classification types I-VI. Both MR images and histological sections were independently reviewed, categorized, and compared. Overall, the classification obtained from the cluster-analyzed MR and histopathology images showed very good agreement for all AHA types (92%, Cohen's kappa = 0.89, P < 0.0001). All plaque types were identified and quantified by SECA with a high degree of correlation between cluster-analyzed MR and manually traced histopathology data. MRI combined with SECA provides an objective method for atherosclerotic plaque component characterization and quantification.

PET for evaluation of differential myocardial perfusion dynamics after VEGF gene therapy and laser therapy in end-stage coronary artery disease

The purpose of this study was to appraise the value of PET in the assessment of the effect of supposedly proangiogenic new therapies such as gene therapy with vascular endothelial growth factor (VEGF) gene and endomyocardial laser therapy.

METHODS

Thirty-five patients with end-stage coronary artery disease and class III (Canadian Cardiovascular Society) angina were included. Myocardial ischemia was evaluated with dipyridamole PET scanning and exercise tolerance with bicycle ergometry. Ten patients were treated with naked plasmid DNA encoding for human VEGF165 (VEGF) and 12 patients were treated with laser therapy (direct myocardial revascularization [DMR]) using an electromechanical mapping system. Thirteen patients were treated with standard medical therapy (control).

RESULTS

In both active treatment groups, angina was reduced in most subjects, except in 2 VEGF and 5 DMR patients. In the control group, no improvement in anginal classification was found, except in 3 subjects. On the PET scan, solely in the VEGF group, the stress perfusion was significantly improved (from 57 +/- 33 to 81 +/- 55 mL/min/100 g; P = 0.031). Furthermore, in the VEGF group, the number of ischemic segments was reduced from 274 +/- 41 to 234 +/- 48 segments (P = 0.004) but not in the DMR group (from 209 +/- 43 to 215 +/- 52 segments) or in the control group (from 218 +/- 18 to 213 +/- 28 segments). Bicycle exercise duration showed slight nonsignificant changes in the VEGF group (from 3.6 +/- 2.0 to 4.6 +/- 2.1 min), in the DMR group (from 5.1 +/- 1.5 to 4.7 +/- 1.3 min), and in the control group (from 3.3 +/- 1.8 to 3.5 +/- 2.3 min).

CONCLUSION

PET showed that intramyocardial gene therapy with the human VEGF165 gene in contrast to laser DMR treatment effectively reduces myocardial ischemia.

Reliability of differentiating human coronary plaque morphology using contrast-enhanced multislice spiral computed tomography: a comparison with histology

BACKGROUND

Initial clinical results indicate that multislice spiral computed tomography (MDCT) might be useful for the noninvasive characterization of human coronary plaque morphology by determining tissue density within the lesions. This seems to be of clinical relevance, because coronary artery disease might be detected at an early stage before calcifications occur and noncalcified plaques that may be more likely to rupture could also be visualized noninvasively. The aim of the present study was to evaluate the reliability of contrast-enhanced MDCT in differentiating human atherosclerotic coronary plaque morphology by comparing it with the histopathologic gold standard.

METHODS AND RESULTS

Twelve human hearts were scanned postmortem using an MDCT (Somatom Volume Zoom; Siemens, Forchheim, Germany) high-resolution computed tomography scanner to detect atherosclerotic coronary plaques. Density measurements were performed within detected plaque areas. The exact location of each plaque was marked at the surface of the heart to assure accurate histopathologic sectioning of these lesions. The plaques were classified according to a modified Stary classification. Seventeen plaques were identified by MDCT. Six plaques were histopathologically classified as lipid rich (Stary III/IV), 6 plaques as intermediate (Stary V), and 5 plaques as calcific (Stary VII). Lipid-rich plaques had a mean density on MDCT of 42 +/- 22 Hounsfield units (HU), intermediate plaques had a mean density of 70 +/- 21 HU, and calcific plaques had a mean density of 715 +/- 328 HU. ANOVA analysis revealed a significant difference in plaque density between the 3 groups (P < 0.0001).

CONCLUSIONS

The comparison with histopathology confirms that tissue density as determined by contrast-enhanced MDCT might be used to differentiate atherosclerotic plaque morphology.

Comparison of Coronary Plaque Rupture Between Stable Angina and Acute Myocardial Infarction

Background— We evaluated the incidence and predictors of single and multiple plaque ruptures in acute myocardial infarction (AMI) and stable angina pectoris (SAP).

Methods and Results— We performed 3-vessel intravascular ultrasound (IVUS) examination in 235 patients: 122 had AMI, and 113 had SAP. Plaque rupture of infarct-related or target lesions occurred in 80 AMI patients (66%) and in 31 SAP patients (27%) ( P <0.001). Non–infarct-related or non–target artery plaque ruptures occurred in 21 AMI patients (17%) and 6 SAP patients (5%) ( P =0.008). Multiple plaque ruptures were observed in 24 AMI (20%) and 7 SAP patients (6%) ( P =0.004). Therefore, at least 1 plaque rupture in any coronary artery was noted in 84 AMI patients (69%) and 35 SAP patients (31%) ( P <0.001). Overall, the only independent clinical predictor of plaque rupture in the infarct-related/target lesion was AMI ( P <0.01; OR, 4.867; 95% CI, 2.734 to 8.661). The only independent clinical predictor of plaque rupture in AMI patients was an elevated C-reactive protein (CRP) level ( P =0.035; OR, 2.139; 95% CI, 1.053 to 4.343). Conversely, in SAP patients, the only independent clinical predictor of plaque rupture was diabetes mellitus ( P =0.034; OR, 2.553; 95% CI, 1.071 to 6.085). The only independent clinical predictor of multiple plaque ruptures was AMI ( P =0.003; OR, 3.752; 95% CI, 1.546 to 9.105).

Conclusions— Three-vessel IVUS imaging showed that culprit lesion plaque rupture, secondary remote plaque ruptures, and multiple plaque ruptures were all more common in AMI patients than SAP patients. In AMI patients, plaque rupture was associated with a high CRP level, whereas in SAP patients, plaque rupture was more common in those with diabetes.

[Evaluating multislice computed tomography for imaging coronary atherosclerosis]

PURPOSE

The purpose of this study was the evaluation of multidetector-row computed tomography (MDCT) for the assessment of atherosclerotic coronary artery vessel wall changes.

METHODS

In an ex vivo study, 17 human hearts were scanned with MDCT and results were compared to histopathology. Morphologic imaging criteria of MDCT for various plaque-types were developed. In a following in vivo study, 94 coronary MDCT angiograms (MDCTA) of patients with suspected coronary artery disease (CAD) were reviewed retrospectively, assessing the diagnostic value of the coronary MDCTA, and determining the number and correlations of the various plaques types as described in the ex vivo study. Additionally, volumetry of calcified and noncalcified plaque components was performed.

RESULTS

In the ex vivo study, MDCT showed a high sensitivity for calcified and non-calcified plaques. Comparing the results with histopathology, characteristic image criteria could be determined for lipid-rich, fibrous and calcified plaque components. Reviewing the contrastenhanced in-vivo MDCT coronary angiographies, presence of noncalcified plaques was proven in 38% of the patients. In 5 patients with a calcium score of 0, presence of coronary atherosclerosis was proven in the contrastenhanced scan.

CONCLUSIONS

MDCT is able to differentiate various plaque components in an ex vivo setting as well as invivo. Contrastenhanced MDCT of the coronary arteries allows for the detection of noncalcified plaques. In vivo volumetry of noncalcified plaques is feasible.

Potential utility of rubidium 82 PET quantification in patients with 3-vessel coronary artery disease

BACKGROUND

Standard perfusion imaging may underestimate the extent of disease in 3-vessel coronary atherosclerosis. This study determined whether positron emission tomography quantification of perfusion reserve by use of rubidium 82 net retention defined a greater extent of disease than the standard approach in patients with 3-vessel disease.

METHODS AND RESULTS

Rb-82 net retention was quantified as an estimation of absolute perfusion at rest and with dipyridamole stress by use of dynamic positron emission tomography imaging. The percent of abnormal myocardial sectors, as compared with a normal database, for a standard and quantification approach was determined. Twenty-three patients were evaluated. Defect sizes were larger in patients with 3-vessel disease (n = 13) by use of quantification methods: 44% +/- 18% of the myocardial sectors were abnormal by use of the standard approach versus 69% +/- 24% of sectors when measured by quantification of the stress-rest perfusion difference (P =.008). In patients with single-vessel disease (n = 10), defect sizes were smaller with quantification methods.

CONCLUSIONS

Quantification of Rb-82 net retention to measure the stress-rest perfusion difference in the myocardium defined a greater extent of disease than the standard approach in this group of patients with triple-vessel disease. More accurate measurement of the extent of coronary artery disease could facilitate better risk stratification and identify more high-risk patients in whom aggressive intervention is required.

Multislice spiral computed tomography coronary angiography in patients with stable angina pectoris

OBJECTIVES

This study was designed to prospectively evaluate the diagnostic performance of multislice spiral computed tomography (MSCT) coronary angiography for the detection of significant lesions in all segments of the coronary tree potentially suitable for revascularization.

BACKGROUND

Noninvasive MSCT coronary angiography is a promising coronary imaging technique.

METHODS

Sixteen-row MSCT coronary angiography was performed in 128 patients (89% men, mean age 58.9 +/- 11.7 years) in sinus rhythm with stable angina pectoris scheduled for conventional coronary angiography. Sixty percent (77 of 128) of patients received pre-scan oral beta-blockers, resulting in a mean heart rate of 57.7 +/- 7.7 beats/min. The diagnostic performance of MSCT for detection of significant lesions (> or =50% diameter reduction) was compared with that of quantitative coronary angiography (QCA).

RESULTS

The sensitivity of MSCT for detection of significant lesions was 92% (216 of 234, 95% confidence interval [CI]: 88 to 95). Specificity was 95% (1,092 of 1,150, 95% CI: 93 to 96), positive predictive value 79% (216 of 274, 95% CI: 73 to 88), and negative predictive value 98% (1,092 of 1,110, 95% CI: 97 to 99). Two > or =50% lesions were missed because of motion artifacts and two because of severe coronary calcifications. The rest (78%, 14 of 18) were detected but incorrectly classified as <50% obstructions. All patients with and 86% (18 of 21) of patients without significant lesions on QCA were correctly classified by MSCT. All patients with significant left main disease or total occlusions were correctly identified on MSCT.

CONCLUSIONS

Sixteen-row MSCT coronary angiography permits reliable detection of significant obstructive coronary artery disease in patients with stable angina in sinus rhythm.

Alterations of endothelin-converting enzyme expression in early and advanced stages of human coronary atherosclerosis

Endothelin-1 is a potent vasoconstrictor and exhibits a mitogenic activity on vascular smooth muscle cells (SMCs). Endothelin-converting enzyme (ECE) is the final key enzyme of endothelin-1 processing. We studied the immunolocalization of ECE in human coronary atherosclerotic lesions with different disease stages. Frozen sections of normal coronary arteries with diffuse intimal thickening (n=13) and those of coronary arteries with early (n=10) or advanced atherosclerotic plaques (n=13) were studied. Monoclonal antibodies used were directed against SMCs, macrophages, endothelial cells, and ECE. For the identification of cell types that express ECE, double immunostaining analysis was also used. In normal coronary arteries, ECE immunoreactivity was observed in luminal endothelial cells and medial SMCs. Early atherosclerotic plaques, which consisted predominantly of SMCs, showed enhanced ECE expression in luminal endothelial cells and intimal SMCs. In advanced atherosclerotic plaques, distinct ECE expression was found in accumulated macrophages and in endothelial cells of intraplaque microvessels, while luminal endothelial cells showed relatively weak immunoreactivity for ECE. In conclusion, the present study demonstrates that the major cell types expressing ECE within the plaques are different between early and advanced stages of human coronary atherosclerosis. Enhanced ECE expression and possible endothelin-1 generation may contribute to SMC proliferation and vasoconstriction in early atherosclerotic stages, and may promote plaque destabilization in advanced atherosclerotic stages.

Accuracy of multidetector spiral computed tomography in identifying and differentiating the composition of coronary atherosclerotic plaques

OBJECTIVES

We evaluated the accuracy of contrast-enhanced multidetector spiral computed tomography (MDCT) for the noninvasive detection and classification of coronary plaques and compared it with intracoronary ultrasound (ICUS).

BACKGROUND

Noninvasive determination of plaque composition and plaque burden may be important to improve risk stratification and to monitor progression of coronary atherosclerosis.

METHODS

We included 46 consecutive patients with a distinctive risk profile, who were investigated by ICUS (Goldvision, 20 MHz, Jomed Inc., Rancho Cordova, California). Due to the inability to slow the heart rate below 65 beats/min (n = 7) and due to renal insufficiency (n = 2), nine of 46 consecutive patients could not be studied by MDCT (Sensation 16, Siemens, Forchheim, Germany).

RESULTS

In the remaining 37 patients, 68 vessels were investigated by ICUS, and 58 of these vessels were visualized by MDCT with image quality sufficient for analysis. In these vessels that were divided in 3-mm sections, MDCT correctly classified 62 of 80 (78%) sections containing hypoechoic plaque areas, 87 of 112 (78%) sections containing hyperechoic plaque areas, and 150 of 158 (95%) sections containing calcified plaque tissue. In 484 of 525 (92%) sections, atherosclerotic lesions were correctly excluded. The MDCT-derived density measurements within coronary lesions revealed significantly different values for hypoechoic (49 HU [Hounsfield Units] +/- 22), hyperechoic (91 HU +/- 22), and calcified plaques (391 HU +/- 156, p < 0.02).

CONCLUSIONS

This study demonstrates that, in the case of diagnostic image quality, contrast-enhanced MDCT permits an accurate identification of coronary plaques and that computed tomography density values measured within plaques reflect echogenity and plaque composition.

[Cardiovascular risk stratification in general practice]

CONCLUSION

The ESC risk charts are helpful to identify high risk patients in general practice who are candidates for preventive treatment. The use of the ESC charts is one important step to initiate "evidence based medicine" in the daily practice of preventive cardiology.Cardiovascular diseases are the most important causes of premature disability and death in Germany. High risk patients however are frequently not recognized. A systematic risk stratification in general practice could identify high risk persons and allow a cost effective treatment approach. The goal of the CAD-scoring week was to identify high risk persons with the use of the ESC risk charts and to evaluate the treatment resulting from risk stratification. In addition the feasibility of the risk charts in daily office routine was to be evaluated. A total of 1122 of 20 000 (5.6%) contacted general physicians agreed to participate in the screening procedure. More than 27 000 patients (> 50 yrs) were evaluated using the ESC risk charts. 21.6% of women (n = 15 018) vs 22.2%* of men (n = 12 361) had markedly elevated blood pressure (> 150 mmHg), 29 vs. 24%* had a total cholesterol > 250 mg/dl (6.5 mmol/l), 25.5 vs 29.9%* smoked and 28.4 vs. 31.9%* had diabetes (*female vs male: p < 0.0003). Altogether 19.4% of women vs. 53% of men were newly identified as high risk patients (risk > 20% in 10 years). More than 40% of these high risk patients received drug treatment for prevention (ASA, lipid lowering drugs or ACE inhibitors). More than 70% of the participating physicians judged the risk charts to be helpful in patient management.

Qualitative und quantitative Beschreibung von myokardialen Ischämien mittels Magnetokardiographie / Qualitative and Quantitative Description of Myocardial Ischemia by means of Magnetocardiography

In the framework of this study quantitative parameters are presented which, derived from magnetocardiographic maps, aid in making a conclusion about ischemia in the myocardium. The analysis is based on the examination of 86 patients with unstable angina, of which 53 exhibited myocardial ischemia with high probability (Group I: angiographically proven stenosis of at least 50% in a coronary artery of first or second order and positive troponin), while in the 33 other patients myocardial ischemia could be ruled out with high probability (Group II: angiographically clean coronary bed and normal troponin values). The negative predictive value (the probability that there is no myocardial ischemia when the magnetocardiogram (MCG) is negative) is 96.2%; the positive predictive value (the probability that there is actually coronary heart disease when the magnetocardiogram is positive) is 91.2%. A 12-lead ECG taken at the same time as the MCG achieved a positive predictive value of 92.8%, but a negative predictive value of 53.4%. Consequently, the boundary values of the parameters selected lead to a markedly distinct separation between patients with myocardial ischemia from those without. For ruling out coronary heart disease in patients with unstable angina the MCG is superior to 12-lead ECG.

[Correlation of clinical and angiographic morphology in unstable angina]

The goal of this study was to compare the clinical presentation and angiographic morphology of patients having an unstable angina pectoris. A total of 321 patients were consecutively studied and underwent cardiac catheterization, mean age 59 + 6 years. According to Braunwald classification, class III was predominant (58%) On coronary angiography, 148 patients had single vessel disease, double-vessel in 92 and triple-vessel in 64. Morphology of coronary artery lesions was classified according to Ambrose's classification, 100 patients had simple lesions (type I or IIA), 204 patients had complex lesions (type IIB, III, intracoronary thrombus or total occlusion). Thoracic rest pain (class III) or postinfarction angina (class C), were associated with the presence of complex lesions. This subgroup of high risk patients would benefit from either Glycoprotein IIb/IIIa blockers with an early revascularisation strategy.

Severity of coronary artery disease in patients with acute coronary syndrome without ST segment elevation is related to baseline troponin I and ST-segment depression

BACKGROUND

Risk assessment for patients admitted with acute coronary syndrome (ACS) is usually based on the past medical history, along with several clinical and biochemical criteria. We hypothesised that stratification of patients with ACS according to the presence of ST-segment depression and results of a qualitative troponin I test would identify subjects with more severe disease who may benefit from an earlier, more aggressive strategy.

MATERIAL/METHODS

The study group consisted of 115 patients hospitalized for typical chest pain (>5 min) occurring within the last 24 hours, with coronary angiography. Blood was drawn for routine biochemistry and qualitative troponin I testing, and ECG was performed on admission.

RESULTS

Patients were classified according to the presence of ST segment depression (ST) and the troponin I test results (T) into three categories: group A, consisting of 34 patients with ST+/T+; group B, consisting of 84 patients with either ST+/T- or ST-/T+; and group C, consisting of 7 subjects with ST-/T-. This stratification correlated significantly with the extent of coronary artery disease (p=0.0004). Significant coronary artery stenosis was significantly more prevalent in patients from groups A and B than in C (p<0.002). No difference in the patients' medical history, apart from more frequent AMI within the past 10 days in group A (p=0.009) was found between groups.

CONCLUSIONS

Admission assessment of ECG and troponin I tests in patients with ACS may identify subjects with significant coronary artery disease, who are at high risk and could benefit from aggressive therapy.

Ethnic differences in the presentation, treatment strategy, and outcomes of percutaneous coronary intervention (a report from the National Heart, Lung, and Blood Institute Dynamic Registry)

Information about the impact of race/ethnicity on adverse outcomes after percutaneous coronary intervention (PCI) in the modern era is limited. Using consecutive patients from the National Heart, Lung, and Blood Institute Dynamic Registry, this study investigated differences in clinical presentation, treatment strategy, and acute and long-term outcomes in 3,669 white, 446 black, 301 Hispanic, and 201 Asian patients who underwent PCI. All comparisons were made to whites. Blacks were more likely than whites to be younger, women, and to present with a higher prevalence of cardiovascular risk factors (hypertension, diabetes, and smoking). Hispanics tended to be younger, hypertensive, diabetic, and to be undergoing their first cardiovascular procedure. Asians were, on average, younger, men, and presented more often with hypertension and diabetes than whites. Although the rate of stent implantation was significantly lower in blacks compared with whites (63% vs 74%, p <0.001), angiographic and procedural success rates were high (> or =95%) and did not differ by race/ethnicity. In-hospital mortality (0.2% vs 1.7%, p <0.05) and death/myocardial infarction (MI)/coronary artery bypass grafting (CABG) (3.1% vs 5.5%, p <0.05) were lower in blacks. All other in-hospital complications were similar to whites. At 1 year, there were no statistical differences in cumulative adverse event rates by ethnicity; however by 2 years there was a modestly higher mortality rate (adjusted RR 1.87; 95% confidence interval 1.15 to 3.04) and adverse event rate (death/MI, death/MI/CABG) among black patients. Thus, although differences in patient demographics, clinical presentation, angiographic characteristics and treatment strategies did not impact the incidence of acute and 1-year adverse outcomes of non-whites, there appears to be a significant reduction in event-free survival among blacks by 2 years.

Characterizing vulnerable plaque features with intravascular elastography

BACKGROUND

In vivo detection of vulnerable plaques is presently limited by a lack of diagnostic tools. Intravascular ultrasound elastography is a new technique based on intravascular ultrasound and has the potential to differentiate between different plaques phenotypes. However, the predictive value of intravascular elastography to detect vulnerable plaques had not been studied.

METHODS AND RESULTS

Postmortem coronary arteries were investigated with intravascular elastography and subsequently processed for histology. In histology, a vulnerable plaque was defined as a plaque consisting of a thin cap (<250 microm) with moderate to heavy macrophage infiltration and at least 40% of atheroma. In elastography, a vulnerable plaque was defined as a plaque with a high strain region at the surface with adjacent low strain regions. In 24 diseased coronary arteries, we studied 54 cross sections. In histology, 26 vulnerable plaques and 28 nonvulnerable plaques were found. Receiver operator characteristic analysis revealed a maximum predictive power for a strain value threshold of 1.26%. The area under the receiver operator characteristic curve was 0.85. The sensitivity was 88%, and the specificity was 89% to detect vulnerable plaques. Linear regression showed high correlation between the strain in caps and the amount of macrophages (P<0.006) and an inverse relation between the amount of smooth muscle cells and strain (P<0.0001). Plaques, which are declared vulnerable in elastography, have a thinner cap than nonvulnerable plaques (P<0.0001).

CONCLUSIONS

Intravascular elastography has a high sensitivity and specificity to detect vulnerable plaques in vitro.

Intravascular ultrasound assessment of patterns of arterial remodeling in the absence of significant reference segment plaque burden in patients with coronary artery disease

OBJECTIVES

We evaluated the impact of reference vessel segment plaque burden on lesion remodeling. Intravascular ultrasound (IVUS) assessment of lesion remodeling compares lesions to reference segments. However, reference segments are rarely disease-free and, therefore, have also undergone remodeling changes.

METHODS

Pre-intervention IVUS was obtained in 274 patients with right coronary artery lesions selected because the right coronary artery has less tapering and fewer side branches than the left anterior descending or left circumflex artery. Standard IVUS definitions were used. Patients were divided according to reference vessel segment plaque burden: group A (minimal reference disease, n = 91), both proximal and distal reference plaque burden <20%; group B (n = 91), either proximal or distal reference plaque burden 20% to 40% but both < or =40%; and group C (n = 92), either proximal or distal reference plaque burden >40%.

RESULTS

The remodeling index measured 0.98 +/- 0.16 in group A (range, 0.68 to 1.47), 1.04 +/- 0.18 in group B (range, 0.67 to 1.91), and 1.04 +/- 0.15 in group C (range, 0.74 to 1.70), analysis of variance p = 0.0208 (p = 0.0234 group A vs. group B and p = 0.0012 group A vs. group C, but p = 0.8 group B vs. group C). Positive, intermediate, and negative remodeling were observed in 24 (26%), 24 (26%), and 43 lesions (48%) in group A; 36 (40%), 28 (30%), and 27 lesions (30%) in group B; and 34 (37%), 39 (42%), and 19 lesions (21%) in group C, respectively (p = 0.0022).

CONCLUSIONS

Negative remodeling occurs commonly in coronary lesions with minimal reference segment disease. Negative remodeling is not just an "artifact" introduced by comparing lesions to diseased reference segments.