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Heart failure is becoming the central problem in cardiology. Its recognition, differential diagnosis, and the monitoring of therapy are intimately coupled with cardiac imaging. Cardiac imaging has witnessed an explosive growth and differentiation, with echocardiography continuing as the first diagnostic step; the echocardiographic exam itself has become considerably more complex than in the last century, with the assessment of diastolic left ventricular function and strain imaging contributing important information, especially in heart failure. Very often, however, echocardiography can only describe the fact of functional impairment and morphologic remodeling, whereas further clarification of the underlying disease, such as cardiomyopathy, myocarditis, storage diseases, sarcoidosis, and others, remains elusive. Here, cardiovascular magnetic resonance and perfusion imaging should be used judiciously to arrive as often as possible at a clear diagnosis which ideally enables specific therapy. [ABSTRACT FROM AUTHOR]

The article discusses on Heart failure and cardiac imaging. Topics include Cardiac imaging plays a central role in its diagnosis and etiological work-up; the large array of imaging modalities, as well as structural and functional parameters, devising a diagnostic strategy that provides diagnostic accuracy without wasting resources; and Multimodality imaging become popular for modalities showing different aspects, which sometimes may be helpful and sometimes not.

The article offers information on the factors that contribute to the predominant role of echocardiography in clinical care. It notes that the emergence of laptop and palmtop type devices has enhanced the portability and universal availability of echocardiography. As stated, echocardiography machines are more cost effective against competitor techniques like gamma camera and magnetic resonance imaging (MRI), among others. Additionally, it mentions that echocardiography machines do not cause radiation effects.

Multiplane transesophageal echocardiography (TEE) is a semi-invasive, very low-risk imaging procedure utilizing the upper gastric and esophageal echo windows to image the heart with the use of high-frequency transducers. It allows for high spatial resolution and access to structures that are routinely not well seen by transthoracic echocardiography, such as the left atrial appendage, the thoracic aorta, and the pulmonary veins, or where transthoracic imaging may be insufficient to answer a specific question, such as the presence of small vegetations, endocarditic abscesses, abnormalities of the interatrial septum, and others. Another important indication is the ventilated patient or the patient in the operating room, where transthoracic echocardiography is unrewarding or impossible. A particular role has emerged for TEE for identifying candidates for mitral valve repair by providing detailed functional and morphologic information on the diseased valve and by checking intraoperatively the results of surgery. A set of cross-sections, defined by anatomic landmarks, has been compiled, which can be systematically sought, evaluated, and modified according to the clinical question in order to extract the maximal information from TEE. [ABSTRACT FROM AUTHOR]

Three-dimensional echocardiography (3DE) improves the accuracy of left ventricle (LV) volumetry compared with the two-dimensional echocardiography (2DE) approach because geometric assumptions in the algorithms may be eliminated. The relationship between accuracy of mode (short- versus long-axis planimetry) and the number of component images versus time required for analysis remains to be determined. Sixteen latex models simulating heterogeneously distorted (aneurysmatic) human LVs (56–303 ml; mean 182 ± 82 ml) were scanned from an ‘apical’ position (simultaneous 2DE and 3DE). For 3DE volumetry, the slice thickness was varied for the short (C-scan) and long axes (B-scan) in 5-mm steps between 1 and 25 mm. The mean differences (true-echocardiographic volumes) were 16.5 ± 44.3 ml in the 2DE approach (95% confidence intervals –27.8 to +60.8) and 0.6 ± 4.0 ml (short axis; 95% confidence intervals –3.4 to +4.6) as well as 2.1 ± 9.9 ml (long axis; 95% confidence intervals –7.8 to +12.0) in the 3DE approach (in both cases, the slice thickness was 1 mm). Above a slice thickness of 15 mm, the 95% confidence intervals increased steeply; in the short versus long axes, these were –6.5 to +8.5 versus –7.0 to +10.6 at 15 mm and –10.1 to +15.7 versus –11.3 to +10.9 at 20 mm. The intra-observer variance differed significantly (p < 0.001) only above 15 mm (short axis). Time required for analysis derived by measuring short-axis slice thicknesses of 1, 15, and 25 mm was 58 ± 16, 7 ± 2 and 3 ± 1 min, respectively. The most rational component image analysis for 3DE volumetry in the in vitro model uses short-axis slices with a thickness of 15 mm. Copyright © 2005 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Abstract: In myocardial contrast echocardiography (MCE), power modulation technique may quantify myocardial perfusion in real-time. However, constant infusion of the contrast agent (CA) complicates handling. This pilot study sought for the clinical feasibility of quantitative MCE by a CA bolus application during Adenosine stress echocardiography to diagnose coronary artery disease (CAD). Twenty-four consecutive patients (pts) with contemporary coronary angiography underwent rest and maximum Adenosine stress. Signal intensity could be calculated in 316/348 left ventricular (LV) segments (91%) (18-segment model). At rest, gamma-variate (alpha) as well as saturation function (beta) was not significantly different in healthy men (n = 268) as well as CAD pts (n = 48) (alpha: 0.34 s-1 versus 0.40 s−1, n.s.; beta: 0.31 s−1 versus 0.35 s−1, n.s.). During Adenosine infusion both values increased in healthy men (alpha: 0.34 ± 0.37 s−1 versus 0.44 ± 0.45 s−1, p < 0.05; beta: 0.31 ± 0.33 s−1 versus 0.40 ± 0.40 s−1, p < 0.01), but not in CAD (alpha: 0.40 ± 0.35 s−1 versus 0.29 ± 0.29 s−1, n.s.; beta: 0.35 ± 0.32 s−1 versus 0.27 ± 0.30 s−1, n.s.). Sensitivity of alpha/beta reserve ≤1 was 65%/67% (specificity 66%/67%) and improved to 88% in both if also wall motion analysis was considered (specificity 59%/65%). A very high negative predictive value of 96%/97% favours the method for excluding CAD. Bolus administration of CA is feasible in quantitative real-time MCE. However, additional consideration of wall motion analysis is required for reasonable sensitivity. Very high negative predictive values favour the potential of the method in excluding the diagnosis. Further need of research work may be encouraged by those findings. (E-mail: nixdorff@ecp-checkup.de) [Copyright &y& Elsevier]