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Aims To evaluate the effects of acute, atrial pacing-induced, reversible myocardial ischaemia on myocardial thickening and integrated backscatter cyclic variations in patients with or without coronary artery disease. Mehtods and results Thirty-six patients with suspected coronary artery disease underwent transoesophageal echocardiography with simultaneous atrial pacing, and coronary angiography. In myocardial segments not related to a significantly narrowed coronary artery, both from patients with and without coronary artery disease, thickening and integrated backscatter cyclic variations were not reduced at peak pacing. In segments related to a significantly narrowed coronary artery, thickening decreased at peak pacing, was still reduced at pacing interruption and recovered at 2 mm, while backscatter cyclic variations, blunted at peak pacing, immediately recovered after pacing interruption. Conclusions During stress-induced myocardial ischaemia, backscatter cyclic variations are blunted and thickening reduced. Returning to baseline, pre-atrial pacing values occur more rapidly in backscatter cyclic variations than when thickening takes place. Evaluation of stress-induced alterations in backscatter cyclic variations may aid in the identification of ischaemia-induced regional left ventricular functional impairment and, hence, in coronary artery disease diagnosis. [ABSTRACT FROM PUBLISHER]

Aims The study was set up to evaluate the functional role of post-infarct preserved microvascular integrity. Low dose dobutamine echocardiography and myocardial contrast echocardiography were used to study patients before hospital discharge who had suffered a recent myocardial infarction and had a patent infarct-related artery (TIMI flow grade 3). Method In the dysfunctioning infarct area, the wall motion score index was calculated at baseline, during the dobutamine infusion and at the 3 month follow-up echocardiogram; contrast echocardiography was performed at the time of coronary angiography, before hospital discharge. Results In patients with more than 50% of the dysfunctioning infarct area opacified at contrast echocardiography (group A), regional wall motion score index decreased, compared to baseline, during the dobutamine infusion (1·97 ± 0·78 vs 2·5 ± 0·35 at baseline; P<0·001) and at follow-up echocardiography (1·83 ± 0·63 vs 2·5 ± 0·35 at baseline; P<0·001). In patients with less extensive microvascular integrity as revealed by contrast echocardiography (group B), regional wall motion score index did not decrease from baseline during either the dobutamine infusion (2·73 ± 0·21 vs 2·81 ± 0·20 at baseline; P=ns) or at follow-up (2·81 ± 0·20 vs 2·81 ± 0·20 at baseline; P=ns). Conclusion In patients with post-infarct dysfunctioning myocardium but a patent infarct-related artery, microvascular integrity, as assessed by myocardial contrast echocardiography, is an indicator of myocardial viability in terms of preserved contractile reserve, as demonstrated by dobutamine infusion and functional recovery at follow-up. [ABSTRACT FROM PUBLISHER]

Myocardial contrast echocardiography is a technique used in experimental and clinical settings in order to visualize the pattern of intramyocardial perfusion. In the acute phase of myocardial infarction, regional absence of flow during myocardial contrast echocardiography delineates the area at risk of necrosis, while the definitive non-perfused area expresses infarct size. Reopening the infarct-related artery, which may be achieved spontaneously by thrombolysis or percutaneous transluminal coronary angioplasty, is not a reliable indicator of intramyocardial reperfusion. If myocardial ischaemia due to coronary occlusion has been sufficiently prolonged and severe, not only myocyte viability, but also microvascular integrity is lost. Myocardial contrast echocardiography, using intracoronary injection of sonicated contrast medium, gives information about microvascular integrity and the effective presence of intramyocardial reflow. Anatomical integrity of microvasculature does not necessarily imply preserved function, and thus the microvessel vasodilating reserve may also be impaired. Myocardial contrast echocardiography has the potential to assess alterations in microvascular function, showing, in the myocardial area with reduced coronary reserve, a relatively reduced increase in echocontrast signal intensity when an intravenous vasodilator agent is administered.(Eur Heart J 1996; 17: 344–353) [ABSTRACT FROM PUBLISHER]

Stress echocardiography is frequently used for the diagnosis of coronary artery disease. Its diagnostic accuracy is strongly influenced by many variables including patient selection, type of stress procedure utilized, stress protocol, echocardiographic imaging modality, digital reviewing technology and expertise in performing and interpreting the examinations. All these must be taken into consideration when evaluating and comparing different studies presented in the literature, as well as in optimal organization (accurate selection of the appropriate stress modality and protocol execution, optimal use of technology, appropriate training of medical and non-medical personnel) of the laboratory involved in stress echocardiography. [ABSTRACT FROM PUBLISHER]

An abstract of the article "Gender and myocardial salvage after reperfusion treatment in acute myocardial infarction. Results of Acute Myocardial Infarction Contrast Imaging (A.M.I.C.I) multicenter trial," by L. Agati and colleagues is presented.

New technologies and the availability of new echo-contrast agents have resulted in advances of diagnostic and prognostic indications of left ventricular opacification (LVO) and myocardial perfusion.The clinical diagnostic value of ultrasound contrast media for LVO and its impact on the clinical decision-making process has been demonstrated in several studies. Recent research aims at developing new quantitative software to improve the delineation of the endocardial border, to assess 3D myocardial perfusion for more accurate regional/global LV function measurements, and to evaluate 4D intra-cardiac flow dynamics.Furthermore, a general consensus has been reached on the incremental value of myocardial contrast echocardiography (MCE) for obtaining additional information in both chronic and acute coronary artery disease (CAD) patients and on the possibility to make quantitative measurements of microvascular damage.Q-contrast(R) is a new software system which provides quantitative measurements to generate parametric images of microcirculatory flow. In a research project including 120 patients, Q-contrast software has been tested to assess the role of contrast in AMI (Acute Myocardial Infarction Contrast Imaging (A.M.I.C.I. Study); good agreement between parametric MCE and SPECT has been found. Preliminary results further confirm that quantitative MCE may provide additional clinical value over qualitative information for the assessment of LV function and of the effects of coronary artery disease on the myocardial microcirculation (viability, ischemia or infarct). [ABSTRACT FROM AUTHOR]

Abstract: New technologies and the availability of new echo-contrast agents have resulted in advances of diagnostic and prognostic indications of left ventricular opacification (LVO) and myocardial perfusion. The clinical diagnostic value of ultrasound contrast media for LVO and its impact on the clinical decision-making process has been demonstrated in several studies. Recent research aims at developing new quantitative software to improve the delineation of the endocardial border, to assess 3D myocardial perfusion for more accurate regional/global LV function measurements, and to evaluate 4D intra-cardiac flow dynamics. Furthermore, a general consensus has been reached on the incremental value of myocardial contrast echocardiography (MCE) for obtaining additional information in both chronic and acute coronary artery disease (CAD) patients and on the possibility to make quantitative measurements of microvascular damage. Q-contrast® is a new software system which provides quantitative measurements to generate parametric images of microcirculatory flow. In a research project including 120 patients, Q-contrast software has been tested to assess the role of contrast in AMI (Acute Myocardial Infarction Contrast Imaging (A.M.I.C.I. Study); good agreement between parametric MCE and SPECT has been found. Preliminary results further confirm that quantitative MCE may provide additional clinical value over qualitative information for the assessment of LV function and of the effects of coronary artery disease on the myocardial microcirculation (viability, ischemia or infarct). [Copyright &y& Elsevier]

An abstract of the article "Early results of a novel ultrasound technology, contrast pulse sequencing, in the evaluation of no-reflow by myocardial contrast echocardiography" by L. Galiuto and colleagues is presented.

An abstract of the article "Persistent and Reversible no Reflow: Predictors and Functional Evolution" by L. Galiuto and colleagues are presented.

An abstract of the article "Predictive value of myocardial contrast echocardiography in the identification of contractile reserve after acute myocardial infarction: role of timing of assessment" by L. Galiuto and colleageus is presented.