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Coronary calcifications can be detected and quantified using electron beam tomography (EBT) or newer generation multi-slice spiral CT (MSCT) scanners. An abundance of data has been acquired by EBT. It could be shown that the amount of coronary calcium correlates to the coronary plaque burden. The detection of coronary calcium with CT imaging methods therefore provides a unique opportunity to detect and quantify coronary atherosclerosis in a subclinical stage. Consequently, the presence and amount of coronary calcium has been shown to be indicative for an increased coronary event risk in symptomatic and asymptomatic individuals. Several clinical studies found a predictive value that was superior to conventional risk factors. Clinically, the use of coronary calcification assessment may therefore be beneficial in patients who, based on traditional risk factors, seem to be at "intermediate risk" for coronary events (10-year event risk 10-20%) in order to decide on the aggressiveness of risk factor modification. The role of coronary calcium quantification to monitor the progression of disease has not been clarified yet. Large, ongoing trials will provide further data as to the relative merit of coronary calcium assessment for risk stratification and will help to more clearly define its clinical role. The relationship between coronary calcium and coronary stenoses is more complex. While the absence of coronary calcifications makes significant coronary stenoses unlikely, even large amounts of coronary calcium do not necessarily indicate the presence of coronary artery stenoses. Pronounced coronary calcifications as an isolated finding should therefore not be the motivation for invasive diagnostic procedures in the absence of other evidence of ischemic heart disease.

Case Report: The case of a 57-year-old woman is reported who was admitted for peripheral hypereosinophilia., Diagnosis: Detailed investigations revealed first of all a hypereosinophilic syndrome with infiltration of bone marrow and lung. The patient suffered more and more from angina pectoris with signs of heart failure. Coronary angiography was therefore carried out which showed normal coronary arteries. With suspicion of myocardial involvement endomyocardial biopsies were performed which revealed the presence of Löfflers endocarditis parietalis fibroplastica. Finally, serological studies for parasites disclosed a positive ELISA test for Toxocara, confirmed later to be rising., Conclusion: Myocardial involvement of hypereosinophilia, caused by Toxocara is not described until now. Further diagnostic by means of pulsed wave tissue Doppler echocardiography provided regional differentiation of a restrictive filling pattern which documented the importance of this new diagnostic tool in myocardial illness.

Coronary angiography remains the diagnostic standard for establishing the presence, site, and severity of coronary artery disease. Electron beam computed tomography (EBCT), a non-invasive imaging method with very high spatial and temporal resolution, is well suited for cardiac imaging. Using a standard protocol, EBCT permits the visualization of the coronary arteries. Stenoses and occlusions of the native arteries and of coronary artery bypass grafts can be reliably diagnosed. Extremely calcified segments have to be excluded from evaluation. Reduced image quality, mainly due to fast vessel motion and superposition of large veins, impairs the results obtained for the right and left circumflex coronary artery. Possible clinical applications are the follow-up after angioplasty (PTCA without stent) and bypass surgery, the exclusion of coronary artery disease in patients with low likelihood of disease, and the evaluation of coronary anomalies.

Electron beam CT, which does not require mechanical movement of an X-ray tube, has a temporal resolution which exceeds that of conventional computed tomography by a factor of about ten. Axial images of the heart can be acquired within 50 to 100 ms with a spatial resolution below 0.5 mm2 and permit precise visualization of all cardiac structures. ECG-triggered acquisition of 30 to 40 axial images (3 mm slice thickness) in a short inspiratory breathhold allows one to sample a 3-dimensional volume data set which covers the complete heart. Overall acquisition times are approximately 30 to 50 seconds. While electron beam CT in general permits a complete cardiac investigation, including morphology, function, and perfusion, the method's most important application is non-invasive imaging of the coronary arteries. Without contrast enhancement, coronary calcifications by EBCT currently constitutes the most sensitive non-invasive marker for the presence even of very early forms of coronary atherosclerosis. Intravenous injection of contrast agent during image acquisition additionally permits the selective visualization of the coronary artery lumen and detection of significant stenoses. This method is especially well suited in the follow-up of coronary interventions and coronary bypass grafting. Breathhold and movement artifacts, superposition of coronary arteries and veins, as well as severe coronary calcifications currently constitute the method's main problems. In spite of these limitations, electron beam CT has been shown to permit clinically valuable non-invasive investigations of the coronary arteries, which may be further refined as technology progresses.

Respiratory gated MR coronary angiography is a new MR imaging technique which permits reconstruction of the coronary arteries from a three-dimensional data set obtained from contiguous parallel sections. In this study, respiratory gated MR angiography was applied to assess significant coronary artery stenoses (> or = 50%). MR imaging was performed in 68 patients (50 men, 18 women) who had been referred to cardiac catheterization because of suspected or known coronary artery disease. The evaluation of coronary artery stenoses was performed in a blinded manner in the proximal, middle, and distal vessel segments after multiplanar coronary reconstruction of the MR images. Of the 680 coronary segments, 275 (40%) were located outside the imaging volume and were, therefore, excluded from further analysis. The highest sensitivity for stenosis detection was found in the proximal left anterior descending (LAD) and right coronary artery (RCA) with 75% and 71%, respectively. The overall sensitivity, however, was low with 48%. The overall specificity was 92%. The positive and negative predictive values were 67% and 85%, respectively. This study shows that significant coronary artery stenoses, especially in the proximal LAD and RCA, can be correctly identified using respiratory gated MR angiography. However, further technical improvements are necessary before this method may become a reliable diagnostic tool in clinical practice.

Fetal magnetocardiography (fMCG) registers the magnetic field generated by the fetal heart. In contrast to the fetal electrocardiogram, fECG permits non-invasive registration of fetal heart activity and documentation of all parts of the PQRST-wave-forms from the second trimenon onwards. This facilitates the determination of cardiac time intervals and establishment of reference values for different stages of pregnancy. We examined 53 women in 104 recordings from the 10th week of gestation onwards (1 to 10 recordings per individual). The fMCG (37 magnetic channels, sampling rate 1024 Hz, bandwidth 1-200 Hz) was recorded non-invasively over the mother's abdomen in a magnetically shielded room. Registration of fetal heart beats was generally successful from the 20/21th week of gestation onwards. In a few cases, fetal heart beats could be registered as early as in the 16th week. Cardiac time intervals and amplitudes of fMCG increased concordantly with fetal growth. Mean P wave duration increased from 31 to 49 ms (p < 0.05), PQ interval from 95 to 107 ms (n.s.) and QRS duration from 36 to 52 ms (p < 0.01). The mean amplitudes of the P and R waves also increased. FMCG, furthermore permits a prenatal diagnosis of fetal cardiac arrhythmias. We recorded fetal arrhythmias in 20 cases (26-38th week), including episodes of ventricular and supraventricular arrhythmias or atrioventricular blockings. Due to its high resolution, fMCG offers new information on the development of fetal cardiac activity which cannot be achieved by conventional methods like cardiotocography or dopplerultrasound. Therefore, fMCG could become a new diagnostic instrument for monitoring fetal wellbeing during pregnancy.

The magnetic fields caused by the human heart's electrical excitation can be recorded without contact over the body surface to obtain the "magnetocardiogram" (MCG). As compared to the conventional electrocardiogram (ECG), the magnetic fields are influenced far less by the conductive properties of the body tissues, so that the MCG permits a more direct and accurate analysis of cardiac electrical excitation. Most important, the MCG allows an exact localization of the underlying electrical activity, based on the recorded magnetic field distribution. For localization, the MCG does not rely on pattern recognition algorithms such as the ECG, instead, a computational 3-D localization is performed using simplified source and volume conductor models. The spatial accuracy of this method, in combination with magnetic resonance imaging for anatomical assignment of the localization results, has been determined to be 10 to 15 mm for sources close to the body surface and 15 to 20 mm for sources in the posterior parts of the heart.Clinically, the magnetocardiogram can be applied for the non-invasive localization of accessory pathways in Wolff-Parkinson-White syndrome, and of ventricular ectopies (PVC and VT). Especially in combination with a subsequent interventional treatment by catheter ablation, the method may improve the clinical management of these conditions.While the registration techniques are standardized in a way that permits routine clinical application, the data evaluation has to be optimized and simplified before this method can be completely handed over for physicians to use.

Electron beam tomography (EBT) is a computed tomography technique with unique spatial and temporal resolution. The aim of the study was to establish and evaluate a protocol for the non-invasive visualization and detection of stenoses of the coronary arteries. Following phantom studies, 103 patients were investigated. Among these, 25 patients after coronary angioplasty (PTCA) were included in a prospective, blinded comparison to coronary angiography. After injection of contrast agent in a peripheral vein, 40 axial cross sections of the heart were acquired, triggered to the ECG (slice thickness 3 mm, 1 mm overlap, pixel size 0.29 x 0.29 mm). Three-dimensional reconstructions of the heart and coronary arteries were performed in the form of "shaded surface display," the results were compared to coronary angiography. In the reconstructions, the proximal and mid section of the LAD was visualized in 94% and 85%, image quality was reduced for the right coronary artery (89%/64%) and left circumflex (74%/54%), mainly due to movement artifacts. EBT displayed a sensitivity of 100% (9/9) for the detection of occlusions and high-grade restenoses in patients after PTCA, due to one false-positive result, specificity was 92% (12/13). Three PTCA patients could not be evaluated due to respiration artifacts. Contrast-enhanced electron beam tomography (EBT) permits the visualization of coronary arteries and the detection of stenoses and occlusions with high sensitivity and specificity.

Electron beam tomography (EBT) is currently the fastest high resolution imaging procedure available. A modern non-invasive method, it provides an accurate spatial representation of the heart including the coronary arteries. Enabling the quantitative detection of microcalcifications in the coronary arteries--a reliable parameter of early-stage CAD-EBT now makes it possible to screen large population strata. In addition, the direct, non-invasive representation of coronary arteries and coronary arterial stenoses has now become possible. Although at present, EBT will probably not completely replace invasive coronary angiography, in specific areas such as evaluating the long-term results of coronary angioplasty (PTCA) or coronary bypass, the method could make invasive diagnostic procedures superfluous.

In a 61 year old male with heart failure and pulmonary congestion the x-ray shows a right paracardial tumor. The patient suffered from a blunt chest trauma 6 years ago. Since that accident he complains about exercise related dyspnea and cardiac arrhythmia with atrial fibrillation. On echocardiography we found a echolucent cystic tumor with a solid center structure surrounded by a thin membrane. Doppler echocardiography revealed a heart cycle dependent flow at its margin. During dextrocardiography rapid opacification only of the peripheral structures of the tumor could be observed. These findings are consistent with a traumatic rupture of the right atrium, and the diagnosis of a posttraumatic aneurysma spurium of the right atrium was established. Surgery confirmed this diagnosis and the aneurysm was extirpated.

Magnetocardiography is a non-invasive biomagnetic technique for measuring magnetic fields produced at the surface of the body when the heart is stimulated to beat. The measurement is contact-free and is independent of tissue resistance. For the first time, magnetocardiography employing multi-channel systems permits the accurate, non-invasive localization of accessory conduction pathways and ectopic ventricular activity.

ECG-alterations under the influence of static magnetic fields were investigated in phantoms (1.5 Tesla), animals and volunteers (4.0 Tesla), as well as in 12 patients (0.5, 1.0, and 1.5 Tesla). Under the influence of static magnetic fields high- and low-frequency voltages are superimposed on the ECG. Motions of the electrical leads induce high-frequency waves, which can alter the ECG to the extent that only the QRS-complex can be recognized. Electrolytes moved by the blood stream in static magnetic fields also induce voltages (Hall-effect) which, according to the patient's position, result in ST-segment- and partial T-wave-elevations or depressions. All ECG-alterations are reversible after exposition to the static magnetic field. Rhythm disturbances do not occur. The results indicate that static magnetic fields up to 4.0 Tesla do not have permanent adverse effects on the human ECG.