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The resting electrocardiogram (ECG) and stress ECG are established tests in the array of cardiovascular diagnostic modalities. In addition to their diagnostic value for structural heart disease and rhythm disorders, ECGs at rest or during stress also contain prognostically relevant information. Several ECG abnormalities, e.g., left ventricular hypertrophy (LVH), Q waves, ST segment changes, left bundle branch block, atrial fibrillation or QT interval prolongation, were shown to be associated with cardiovascular events. Differences in study design, the cohorts of investigation and morphological definitions of ECG abnormalities may in part be responsible for the abnormalities not being implemented in risk stratification algorithms. The non-ST-segment-related variables in stress testing, e.g., functional capacity, chronotropic (in)competence, heart rate (HR) recovery, and the HR/ST index and slope, could be identified as prognostically relevant markers in population-based studies. For many of these resting and stress ECG-based abnormalities, associations with the extent of subclinical atherosclerosis in persons without established coronary heart disease were observed, indicating a preclinical relationship between epicardial atherosclerosis and myocardial pathology. The resting and the stress ECG provide a number of prognostically relevant indices that can easily be obtained in routine clinical practice, but have thus far found little acceptance for risk stratification of asymptomatic individuals.

Intima-media thickness (IMT) of extracranial carotid arteries, measured by B-mode sonography, is considered to be a marker of subclinical atherosclerosis. It is a fast, inexpensive, noninvasive and pain-free examination, which can be conducted by trained physicians or specialized staff. A positive association between IMT and established risk factors of a coronary heart disease (CHD) and established CHD has been demonstrated in several studies. Population-based trials reported an increased probability of cardio- and cerebrovascular events with increased IMT. Additionally, B-mode ultrasonography detects plaque and vascular stenosis. There is a limited association between both parameters and coronary atherosclerosis, so that severity of atherosclerosis in one vascular territory permits no estimate of plaque burden in another vascular territory.

The Heinz Nixdorf Recall Study, which was inaugurated in 2000, is an ongoing population-based study to evaluate the prediction of cardiovascular events by integrating new imaging and nonimaging modalities in risk assessment. A focus is the additional prognostic value of coronary artery calcification (CAC). Currently used risk stratification algorithms often describe the individuals' risk based on few established risk factors only inaccurately. Using noninvasive quantification of CAC progression, the natural history of atherosclerosis with its repetitive, frequently subclinical plaque ruptures, may detect an unstable course of the disease long before the disease irreversibly manifests in sudden death or myocardial infarction. While the independent additional prognostic value of CAC quantification has been shown in asymptomatic patients at intermediate risk, only few studies provided evidence for an independent prognostic value of serial CAC measurements. In the Heinz Nixdorf Recall Study, the impact of established and new risk factors, e.g., the metabolic syndrome, psychosocial and environmental risk factors, or genetic variables, can be assessed. Further, the association of CAC progression with the incidence of other cardiovascular diseases such as heart failure or aortic or aortic valve calcification can be described. Since April 2006, the participants of the study return to the study center 5 years after baseline recruitment to assess health status and to determine the risk factor profile. Based on recently published data, serial CAC measurements have been granted allowing for (1) characterization of the natural history of CAC progression, and (2) identification of its determinants. The rationale of serial CAC quantification is discussed in this article.The Heinz Nixdorf Recall Study will contribute to the appraisal of new imaging modalities in risk stratification.

Calcified aortic stenosis is the predominant valve disease. Patients affected are most commonly elderly people, who often show associated comorbidities like reduced left ventricular function, impaired renal function, and pulmonary hypertension. The risk of open-heart surgery is elevated. Balloon aortic valvuloplasty enables a reduction of symptoms, an increase in physical performance, and, therefore, an improved quality of life. However, a reduction in mortality cannot be reached with this method. New techniques and improved equipment induced a "revival" of balloon aortic valvuloplasty, which has been introduced almost 20 years ago. In addition, brachytherapy after balloon valvuloplasty has recently been investigated and represents an interesting approach to reduce early restenosis. The technical improvement of balloon valvuloplasty is the percutaneous heart valve, which is under present clinical investigation. The antegrade/transseptal and retrograde approaches are used, as is the transapical access to the left ventricle. Even if long-term results are not yet available and the procedures still require technical improvement, especially minimization of catheter size, percutaneous valve replacement is a new chapter in the treatment of the calcified aortic stenosis.

Approximately 20-30% of patients with cardiac chest pain have a normal coronary angiogram. In about 5% of these patients, a myocardial bridge can be identified. The characteristic feature is systolic compression of an epicardial vessel, usually the left anterior descending artery (LAD), with the angiographic "milking effect". Using modern imaging techniques, such as intravascular ultrasound (IVUS), intracoronary Doppler ultrasound (ICD) and intracoronary pressure wires, the pathophysiological consequence of myocardial bridging could be established. While previously considered a clinically insignificant variant, ICD recordings demonstrated an increased flow velocity in the tunneled segment. Frame-by-frame IVUS analysis revealed a delayed relaxation after systolic compression, which may extend significantly into diastole. This explains both the impaired coronary flow reserve and ischemia. In IVUS, a circular or eccentric rhythmic compression of the vessel is visible, which may be partial or complete. Latest computed tomography technology can also be used to visualize myocardial bridging noninvasively. Provocation tests, such as application of nitroglycerin, orciprenaline, dobutamine or atrial stimulation, may augment systolic compression and explain symptoms and the beneficial effect of beta-blockers. In severe cases (i.e. limiting symptoms with ischemia despite medication), surgical myotomy may be performed after careful appraisal of the benefit-risk ratio. A high restenosis and complication rate associated with coronary stenting precludes a general recommendation of this interventional approach. Whether drug-eluting stents help to overcome this limitation remains to be shown. Long-term prognosis is good, although previous investigations have been performed in a limited number of cases only.

Background: Invasive, selective coronary angiography remains the "gold standard" of direct visualization of epicardial coronary arteries. Technical advances in recent years and improvements in image quality in both electron beam computed tomography (EBT) and multislice spiral/helical computed tomography (MSCT) brought along an increasing interest in the potential clinical role of noninvasive computed tomographic coronary angiography (CTCA)., Potential and Limitations: Measurement of coronary calcification permits quantitative estimation of overall coronary plaque burden and thereby allows assessment of cardiovascular risk and likelihood of the presence of a significant stenosis. However, the precise site and degree of stenoses cannot be measured. Contrast-enhanced CTCA lumenography permits visualization of epicardial coronary artery stenoses with a sensitivity and specificity of about 90%. Noncalcified plaques may also be detected in individual cases, but very few data are available on this aspect of CTCA. Image artifacts due to rapid motion, especially in the distal segments of the right and circumflex coronary arteries, may preclude reliable assessment of 20-30% of these segments. Also, in-stent restenoses and distal bypass anastomoses will, in the foreseeable future, remain difficult to confidently diagnose by CTCA. Combined assessment of calcified plaque burden and CTCA may enhance diagnostic accuracy especially in patients with low or moderate calcium scores. In the presence of heavy calcifications, stenoses may be masked., Indications: Noninvasive CT-based evaluation of coronary arteries seems useful in patients with a low to intermediate pretest likelihood for significant coronary artery disease (CAD). This holds for several ACC/AHA class II indications described for invasive, selective coronary angiography and for few class I indications. Further prospective studies are required to establish the clinical value of combined assessment of coronary calcium quantification and CTCA.