shu-508 and Coronary-Disease

The development of new contrast agents and new imaging methods has lead to an emerging field of applications for myocardial contrast echocardiography (MCE) in patients suffering from chronic ischemic heart disease. Echo contrast allows the assessment of myocardial perfusion (MP) by imaging the coronary microcirculation. Several echocardiographic modalities are available, the main difference between them being the acoustic power needed to perform the study. MP is evaluated by assessing the changes in myocardial videointensity that occur after intravenous contrast injection. Evaluation of these patients is performed by using different techniques. Evaluation of coronary stenosis may be performed by using stress tests or without its use. Coronary artery stenosis > 50% of the coronary luminal diameter reveals a decreased hyperemic response when myocardial oxygen demand is increased. Different methods to evaluate the presence of relevant coronary stenosis have been developed: evaluation of myocardial blood flow reserve, evaluation of myocardial blood volume, and evaluation of the transmural distribution of myocardial blood flow. The combination of wall motion analysis with MCE assessment has been demonstrated to achieve the best balance between sensitivity (86%) and specificity (88%), with the highest accuracy (86%). Without the need of any stress, the ratio systolic/diastolic myocardial blood volume has been described to increase with the presence of a epicardial coronary stenosis and it may be measured by MCE. Myocardial viability is also one of the potentials of MCE. Microvascular integrity, demonstrated by MCE, is an indicator of preserved viability and predicts functional recovery that has been validated in the setting of chronic left ventricular dysfunction secondary to chronic coronary artery disease and in the setting of post acute myocardial infarction left ventricular dysfunction.. contrast echocardiography provides an interesting tool that offers the potential of a complete evaluation of patients with chronic coronary artery disease. This includes both diagnostic and prognostic evaluation.

Topics: Albumins; Blood Volume; Chronic Disease; Contrast Media; Coronary Circulation; Coronary Disease; Echocardiography; Fluorocarbons; Humans; Microcirculation; Phospholipids; Polysaccharides; Prognosis; Sulfur Hexafluoride

The non-invasive assessment of coronary artery disease (CAD) in patients with left bundle branch block (LBBB) is troublesome. In this study, we investigated the diagnostic accuracy of myocardial contrast echocardiography (MCE) with adenosine to detect CAD in asymptomatic patients with LBBB, and we compared it with single photon emission computed tomography (SPECT) with adenosine.. Forty-seven patients with LBBB, and no previously documented CAD, initially underwent SPECT imaging and 1-3 days later MCE. Coronary arteriography was performed within 1 week from the latter procedure.. The overall sensitivity, specificity, positive predictive value, negative predictive value, diagnostic accuracy, and kappa index of concordance of SPECT were 73%, 72%, 44%, 90%, 72%, and 0.37+/-0.13, respectively, whereas those of MCE were 91%, 92%, 77%, 97%, 92%, and 0.77+/-0.1, respectively (p<0.05 for all comparisons). Significant CAD was present in 11 patients (23%). Left anterior descending coronary artery was involved in 8 patients, left circumflex artery in 2 patients, and right coronary artery in 4 patients. Concerning the left anterior descending artery disease detection, SPECT had a sensitivity of 75%, a specificity of 79%, a positive predictive value of 43%, a negative predictive value of 94%, and a diagnostic accuracy of 79%. The respective values of MCE were 100% for all of the above variables.. MCE with adenosine has a higher global diagnostic accuracy compared to SPECT for the detection of CAD in patients with LBBB, mainly due to the poor specificity of SPECT concerning perfusion defects detection in the left anterior descending artery territory.

Topics: Adenosine; Bundle-Branch Block; Contrast Media; Coronary Disease; Echocardiography, Doppler; Female; Humans; Male; Middle Aged; Polysaccharides; ROC Curve; Sensitivity and Specificity; Tomography, Emission-Computed, Single-Photon; Vasodilator Agents

The value of stress harmonic power Doppler imaging (HPDI) for the evaluation of myocardial perfusion has never been assessed in patients after acute coronary syndrome (ACS).. To evaluate the agreement between stress HPDI and single photon emission computed tomography (SPECT) imaging for the assessment of myocardial perfusion after unstable angina or myocardial infarction.. Thirty patients with a recent ACS underwent HPDI and SPECT. Images were obtained at rest and during dipyridamole infusion (0.56 mg/kg over 4 min). Apical two- and four-chamber views were used for HPDI. Ten myocardial segments were scored for myocardial perfusion. Semiquantitative and quantitative video intensity analysis with background subtraction were performed.. Concordance by patients between quantitative HPDI and SPECT was 76% (kappa=0.40, Phi=0.46) for normal versus abnormal perfusion. When semiquantitative analysis was used, concordance was 72% (kappa=0.42, Phi=0.46). Agreement between methods was best in the left anterior descending artery territory for quantitative (80%) (kappa=0.60, Phi=0.60) and semiquantitative analysis (78%) (kappa=0.51, Phi=0.60) for normal versus abnormal perfusion. Discrepancies between HPDI and SPECT were most important in the circumflex territory, with a concordance of 59% (kappa=0.22) for identification of normal perfusion versus irreversible and reversible defects.. These results suggest that HPDI can detect myocardial perfusion at rest and during pharmacological stress in patients after a recent ACS. Given the suboptimal agreement with SPECT, further advances are required before the routine use of contrast echocardiography is possible for the assessment of myocardial perfusion.

Topics: Acute Disease; Aged; Aged, 80 and over; Contrast Media; Coronary Circulation; Coronary Disease; Echocardiography; Female; Humans; Male; Middle Aged; Organophosphorus Compounds; Organotechnetium Compounds; Polysaccharides; Radiopharmaceuticals; Research Design; Syndrome; Tomography, Emission-Computed, Single-Photon

Topics: Contrast Media; Coronary Disease; Echocardiography, Doppler; Feasibility Studies; Image Enhancement; Image Processing, Computer-Assisted; Polysaccharides; Stroke Volume

Topics: Contrast Media; Coronary Circulation; Coronary Disease; Echocardiography, Doppler; Female; Heart; Humans; Male; Middle Aged; Polysaccharides; Sensitivity and Specificity; Tomography, Emission-Computed, Single-Photon

We evaluated the value of coronary flow reserve (CFR), as determined by transthoracic Doppler echocardiography (TTDE), for physiologic assessment of coronary artery stenosis severity, and we compared TTDE measurements with those obtained by exercise thallium-201 (Tl-201) single-photon emission computed tomography (SPECT).. Coronary flow reserve measurements by TTDE have been reported to be useful for assessing angiographic left anterior descending coronary artery (LAD) stenosis. However, discrepancies exist between angiographic and physiologic estimates of coronary lesion severity.. We studied 36 patients suspected of having coronary artery disease. The flow velocity in the distal LAD was measured by TTDE both at rest and during intravenous infusion of adenosine. Coronary flow reserve was calculated as the ratio of hyperemic to basal peak (peak CFR) and mean (mean CFR) diastolic flow velocities. The CFR measurements by TTDE were compared with the results of Tl-201-SPECT.. Complete TTDE data were acquired for 33 of 36 study patients. Of these 33 patients, Tl-201-SPECT confirmed reversible perfusion defects in the LAD territories in 12 patients (group A). Twenty-one patients had normal perfusion in the LAD territories (group B). Peak CFR and mean CFR (mean value +/- SD) were 1.5 +/- 0.6 and 1.5 +/- 0.7 in group A and 2.8 +/- 0.8 and 2.7 +/- 0.7 in group B, respectively. Both peak and mean CFR < or = 2.0 predicted reversible perfusion defects, with a sensitivity and specificity of 92% and 90%, respectively.. Noninvasive measurement of CFR by TTDE provides data equivalent to those obtained by Tl-201-SPECT for physiologic estimation of the severity of LAD stenosis.

Topics: Aged; Blood Flow Velocity; Contrast Media; Coronary Angiography; Coronary Circulation; Coronary Disease; Echocardiography, Doppler; Female; Humans; Male; Middle Aged; Polysaccharides; Sensitivity and Specificity; Thallium Radioisotopes; Tomography, Emission-Computed, Single-Photon

To compare the accuracy and feasibility of harmonic power Doppler and digitally subtracted colour coded grey scale imaging for the assessment of perfusion defect severity by single photon emission computed tomography (SPECT) in an unselected group of patients.. Cohort study.. Regional cardiothoracic unit.. 49 patients (mean (SD) age 61 (11) years; 27 women, 22 men) with known or suspected coronary artery disease were studied with simultaneous myocardial contrast echo (MCE) and SPECT after standard dipyridamole stress.. Regional myocardial perfusion by SPECT, performed with (99m)Tc tetrafosmin, scored qualitatively and also quantitated as per cent maximum activity.. Normal perfusion was identified by SPECT in 225 of 270 segments (83%). Contrast echo images were interpretable in 92% of patients. The proportion of normal MCE by grey scale, subtracted, and power Doppler techniques were respectively 76%, 74%, and 88% (p < 0.05) at > 80% of maximum counts, compared with 65%, 69%, and 61% at < 60% of maximum counts. For each technique, specificity was lowest in the lateral wall, although power Doppler was the least affected. Grey scale and subtraction techniques were least accurate in the septal wall, but power Doppler showed particular problems in the apex. On a per patient analysis, the sensitivity was 67%, 75%, and 83% for detection of coronary artery disease using grey scale, colour coded, and power Doppler, respectively, with a significant difference between power Doppler and grey scale only (p < 0.05). Specificity was also the highest for power Doppler, at 55%, but not significantly different from subtracted colour coded images.. Myocardial contrast echo using harmonic power Doppler has greater accuracy than with grey scale imaging and digital subtraction. However, power Doppler appears to be less sensitive for mild perfusion defects.

Topics: Aged; Cohort Studies; Contrast Media; Coronary Disease; Dipyridamole; Echocardiography, Doppler; Echocardiography, Doppler, Color; False Positive Reactions; Feasibility Studies; Female; Humans; Male; Middle Aged; Organophosphorus Compounds; Organotechnetium Compounds; Polysaccharides; Radiopharmaceuticals; Sensitivity and Specificity; Tomography, Emission-Computed, Single-Photon

To determine whether myocardial contrast echocardiography can be used to quantify collateral derived myocardial flow in humans.. In 25 patients undergoing coronary angioplasty, a collateral flow index (CFI) was determined using intracoronary wedge pressure distal to the stenosis to be dilated, with simultaneous mean aortic pressure measurements. During balloon occlusion, echo contrast was injected into both main coronary arteries simultaneously. Echocardiography of the collateral receiving myocardial area was performed. The time course of myocardial contrast enhancement in images acquired at end diastole was quantified by measuring pixel intensities (256 grey units) within a region of interest. Perfusion variables, such as background subtracted peak pixel intensity and contrast transit rate, were obtained from a fitted gamma variate curve.. 16 patients had a left anterior descending coronary artery stenosis, four had a left circumflex coronary artery stenosis, and five had a right coronary artery stenosis. The mean (SD) CFI was 19 (12)% (range 0-47%). Mean contrast transit rate was 11 (8) seconds. In 17 patients, a significant collateral contrast effect was observed (defined as peak pixel intensity more than the mean + 2 SD of background). Peak pixel intensity was linearly related to CFI in patients with a significant contrast effect (p = 0.002, r = 0.69) as well as in all patients (p = 0.0003, r = 0.66).. Collateral derived perfusion of myocardial areas at risk can be demonstrated using intracoronary echo contrast injections. The peak echo contrast effect is directly related to the magnitude of collateral flow.

Topics: Aged; Angioplasty, Balloon, Coronary; Contrast Media; Coronary Circulation; Coronary Disease; Echocardiography; Humans; Image Processing, Computer-Assisted; Polysaccharides; Sensitivity and Specificity

The aim of this study was to evaluate if a reduced coronary flow reserve determined by transthoracic echocardiography alone or combined with contrast agents may represent a predictive index of significant left anterior descending coronary artery (LAD) stenosis.. Thirty-four patients (mean age 59+/-9 years) undergoing coronary angiography for coronary artery disease were studied. Coronary stenosis was classified (according to visually determined percent narrowing) as severe (> 75%), moderate (40 to 75%) and mild (< 40%). Coronary blood flow velocities were recorded in each patient at baseline and after low-dose dipyridamole administration by use of a 3.5 MHz transducer with a machine equipped with second harmonic capability and nondirectional color Doppler software. Coronary flow reserve was defined as the ratio of hyperemic to basal diastolic peak velocity.. Adequate Doppler recordings in the LAD were obtained by transthoracic echocardiography in 26/34 patients (76%); the infusion of Levovist allowed for the visualization of LAD flow in a further 7 patients, with an overall feasibility of 97%. Coronary flow reserve was significantly higher in the group of patients with mild coronary lesions (2.3+/-0.3) than in patients with moderate (1.68+/-0.29, p = 0.0004) or severe (1.49+/-0.39, p = 0.0005) LAD stenosis.. By use of transthoracic echocardiography combined with contrast agents it is possible to visualize blood flow velocities in the LAD and to evaluate coronary flow reserve after dipyridamole infusion with a non-invasive approach. Combined with angiographic findings, this diagnostic approach could be useful in giving additional information to assess the functional significance of a stenotic coronary lesion.

Topics: Blood Flow Velocity; Contrast Media; Coronary Angiography; Coronary Circulation; Coronary Disease; Coronary Vessels; Dipyridamole; Echocardiography, Doppler, Color; Feasibility Studies; Female; Humans; Injections, Intravenous; Male; Middle Aged; Observer Variation; Polysaccharides; Prognosis; Reproducibility of Results; Vasodilator Agents

We tested the hypothesis that coronary flow reserve (CFR) in the left anterior descending coronary artery (LAD) as assessed by a new noninvasive method (contrast-enhanced transthoracic second harmonic echo Doppler) is in agreement with CFR measurements assessed by intracoronary Doppler flow wire.. Contrast-enhanced transthoracic second harmonic echo Doppler is a novel noninvasive method to detect blood flow velocity and reserve in the LAD. However, it has not yet been validated versus a gold-standard method.. Twenty-five patients undergoing CFR assessment in the LAD by Doppler flow wire were also evaluated by contrast-enhanced transthoracic Doppler to record blood flow in the distal LAD at rest and during hyperemia obtained by adenosine i.v. infusion. In five patients CFR was evaluated twice (before and after angioplasty).. As a result of the combined use of i.v. contrast and second harmonic Doppler technology, feasibility in assessing coronary flow reserve equaled 100%. The agreement between the two methods was high. In fact, in all but five patients the maximum difference between the two CFR measurements was 0.38. Overall, the prediction (95%) interval of individual differences was -0.69 to +0.72. Reproducibility of CFR measurements was also high. The limits of the agreement (95%) between the two measurements were -0.32 to +0.32.. Coronary flow reserve in the LAD as assessed by contrast-enhanced transthoracic echo Doppler along with harmonic mode concurs very closely with Doppler flow wire CFR measurements. This new noninvasive method allows feasible, reliable and reproducible assessment of CFR in the LAD.

Topics: Adenosine; Adult; Aged; Angioplasty, Balloon, Coronary; Blood Flow Velocity; Contrast Media; Coronary Circulation; Coronary Disease; Echocardiography, Doppler; Feasibility Studies; Female; Fourier Analysis; Humans; Image Enhancement; Image Processing, Computer-Assisted; Male; Middle Aged; Polysaccharides; Reproducibility of Results

This study was designed to verify the usefulness of transesophageal Doppler recording of blood flow velocity in the proximal left anterior descending coronary artery, after a peripheral injection of a lung-crossing contrast agent (SHU 508A), in detecting and locating a hemodynamically significant stenosis (vessel narrowing > or = 50%) affecting this portion of the vessel.. Transesophageal Doppler echocardiography has a limited diagnostic impact on the evaluation of proximal left anterior descending coronary artery stenoses. Peripheral injection of SHU 508A, a lung-crossing contrast agent enhancing Doppler signal to noise ratio in coronary arteries, may allow recording of localized disturbed blood flow velocity at the stenosis site even in the absence of a clear B-mode visualization of the vessel.. Transesophageal Doppler echocardiography, before and after echo contrast injection, was performed in 31 patients who underwent coronary angiography. Using color Doppler as a guide, pulsed wave Doppler recording of blood flow velocity in the left anterior descending coronary artery was attempted to detect a localized increase in blood flow velocity. B-mode evaluation of the vessel was also performed.. Angiography showed a significant proximal left anterior descending coronary artery stenosis in 16 patients (group 1) and no stenosis in 15 patients (group 2). In 15 of 16 group 1 patients, Doppler after contrast injection revealed a localized velocity increase of at least 50% of the reference value; mean (+/-SD) percent increase in velocity was 150 +/- 89% (range 367% to 0%). In group 2 Doppler after contrast injection revealed a mild localized increase in velocity in four patients and no increase in velocity in the remaining 11 patients; mean (+/-SD) percent increase in velocity was 5 +/- 7% (range 21% to 0%, p < 0.001 vs. percent increase in group 1). When a percent velocity increase > or = 50% of the reference value was considered a positive criterion for detecting significant stenosis, the sensitivity and specificity were 92% and 100% respectively. The sensitivity of the evaluation before contrast injection or considering B-mode imaging alone was much lower (25% and 19%, respectively, p < 0.001 vs. evaluation after contrast injection). In addition, color Doppler after contrast injection correctly located the stenosis along the vessel, as compared with angiography.. Blood flow evaluation of the proximal left anterior descending coronary artery by transesophageal Doppler echocardiography after contrast injection is a feasible and reliable method for detecting and locating significant stenoses affecting this part of the vessel and is an improvement over the traditional ultrasound approach.

Topics: Aged; Blood Flow Velocity; Contrast Media; Coronary Angiography; Coronary Circulation; Coronary Disease; Echocardiography, Doppler; Echocardiography, Transesophageal; Female; Humans; Male; Middle Aged; Polysaccharides

Recent studies have shown that the saccharide based echocardiographic contrast agent SH U 508 A opacifies the left ventricle after i.v. injection, thus possibly improving endocardial border definition. This study was performed to determine whether SH U 508 A can enhance the wall motion analysis in suboptimal echocardiographic images at rest and following pharmacological stress. Ten male patients (mean 58 years) exhibiting > or = 30% endocardial border dropout were examined prior to a diagnostic left heart catheterization. Five patients were stressed with Dobutamine, 5 with Dipyridamole. The wall motion was assessed visually (qualitatively) as well as computer-aided (quantitatively). The concordance between left ventricular angiography as 'gold standard' and resting echocardiography regarding the wall motion analysis was significantly improved from 64.5% to 90.3% following the injection of SH U 508 A (p < 0.05). A delineation score (0 = not delineated, 1 = delineated) of 12 individual wall segments was used. The mean delineation score at baseline was 6.1 +/- 1.4 at rest and 6.6 +/- 1.9 during stress. SH U 508 A significantly (p < 0.01) increased the score to 9.6 +/- 1.9 and 10.3 +/- 1.7, respectively. The intraobserver variability for assessing the delineation score was significantly (p < 0.04) improved by SH U 508 A. SH U 508 A, however, did not improve the quantitative assessment of the left ventricular function. Only 40% of the patients could be analyzed following SH U 508 A injection. No severe adverse reactions were seen. SH U 508 A led to a significant, clinically important, improvement in the interpretation of stress echocardiograms in patients with inconclusive routine echocardiograms.

Topics: Adult; Aged; Contrast Media; Coronary Disease; Dipyridamole; Dobutamine; Echocardiography; Endocardium; Humans; Image Processing, Computer-Assisted; Male; Middle Aged; Observer Variation; Polysaccharides

Topics: Adult; Contrast Media; Coronary Disease; Coronary Vessels; Echocardiography, Transesophageal; Female; Humans; Image Enhancement; Male; Middle Aged; Polysaccharides; Sensitivity and Specificity

Stress echocardiography has recently gained increased importance as a method for assessment of left ventricular function. However, suboptimal image quality in some patients may limit use of this technique. In the present study, 10 patients with moderate image quality in the resting echocardiograms (apical 4-chamberview) were reinvestigated after administration of the intravenous transpulmonary saccharide-based left heart contrast agent SHU 508 A. Duration of contrast enhancement in the left ventricle determined by visual assessment was 135 s (SEE +/- 39) at rest and 112 s (+/- 24) during maximum exercise. On a scale ranging from O (no contrast) to 4 (excessively strong contrast) enhancement averaged 2.5 at rest and during exercise. The left ventricle was divided into three segments (septum, apex, lateral wall) and delineation of the endocardial border was assessed. Detection of the border improved significantly after contrast administration, especially at the lateral wall. Despite better visual assessment of the endocardial border, there was no improvement in automatic or semi-automatic contour recognition. No clinically significant side-effects were observed. Three patients reported a sensation of warmth at the injection site. In conclusion, intravenous administration of SHU 508 A improves visual detection of the left ventricular endocardial border in patients with suboptimal image quality and helps to achieve acceptable diagnostic accuracy with stress echocardiography in these patients.

Topics: Aged; Angioplasty, Balloon, Coronary; Cardiac Output; Cardiomyopathies; Contrast Media; Coronary Artery Bypass; Coronary Disease; Echocardiography; Exercise Test; Female; Graft Occlusion, Vascular; Hemodynamics; Humans; Male; Middle Aged; Polysaccharides; Veins; Ventricular Function, Left