It is very useful to evaluate the content and 3D distribution of extracellular matrix non-destructively in tissue engineering. This study evaluated the feasibility of using micro-computed tomography (µCT) with Hexabrix to measure quantitatively sulfated glycosaminoglycans (GAGs) of engineered cartilage. Rabbit chondrocytes at passage 2 were used to produce artificial cartilages in polyglycolic acid scaffolds in vitro. Engineered cartilages were incubated with Hexabrix 320 for 20 min and analyzed via µCT scanning. The number of voxels in the 2D and 3D scanning images were counted to estimate the amount of sulfated GAGs. The optimal threshold value for quantification was determined by regression analysis. The 2D µCT images of an engineered cartilage showed positive correlation with the histological image of Safranin-O staining. Quantitative data obtained with the 3D µCT images of 14 engineered cartilages showed strong correlation with sulfated GAGs contents obtained by biochemical analysis (R² = 0.883, p < 0.001). Repeated exposure of engineered cartilages to Hexabrix 320 and µCT scanning did not significantly affect cell viability, total DNA content, or the total content of sulfated GAGs. We conclude that µCT imaging using Hexabrix 320 provides high spatial resolution and sensitivity to assess the content and 3D distribution of sulfated GAGs in engineered cartilages. It is expected to be a valuable tool to evaluate the quality of engineered cartilage for commercial development in the future.
Cartilage* ; Cell Survival ; Chondrocytes ; DNA ; Extracellular Matrix ; Glycosaminoglycans* ; In Vitro Techniques ; Ioxaglic Acid ; Polyglycolic Acid ; Tissue Engineering

BACKGROUND AND OBJECTIVES: We investigated the effects of commonly used contrast media (CM) on myocardial ischemia-reperfusion injury in isolated rat hearts. SUBJECTS AND METHODS: Isolated rat hearts were subjected to 30 minutes of regional ischemia and 2 hours of reperfusion. The following CM (1 mL/1 L Krebs-Henseleit buffer) were randomly perfused for 15 minutes beginning 5 minutes before reperfusion and ending 10 minutes after reperfusion: iohexol (n=8), iopromide (n=8), ioversol (n=8), iomeprol (n=8), iopamidol (n=7), ioxaglate (n=8), and iodixanol (n=7). The effects of a direct bolus injection of undiluted iohexol, iopromide, or ioxaglate (each n=6) via the aortic root immediately prior to reperfusion were also evaluated. The area of necrosis, expressed as the percentage of the area at risk (AN/AR), and cardiodynamic variables were measured. RESULTS: The AN/AR of the control and experimental groups in the order described in methods was 33.7+/-6.4%, 30.3+/-7.4%, 34.7+/-12.6%, 29.2+/-10.2%, 20.9+/-7.6%, 22.6+/-8.7%, 18.8+/-7.9%, and 19.9+/-11.4%, respectively. Groups that received iomeprol and ioxaglate exhibited significantly decreased AN/AR values compared to those of control hearts (p=0.042 and p=0.013). No significant differences in the AN/AR were observed between control hearts and the groups injected with a single bolus of CM. No significant hemodynamic changes were noted after reperfusion among the groups. CONCLUSION: The overall effects of the CM on coronary reperfusion were not deleterious, and better effects were noted in two CM groups. However, it is unclear whether this result was attributed to a specific physiochemical property of the CM.
Animals ; Contrast Media* ; Heart* ; Hemodynamics ; Iohexol ; Iopamidol ; Ioxaglic Acid ; Ischemia ; Myocardial Infarction ; Myocardial Reperfusion ; Necrosis ; Rats* ; Reperfusion ; Reperfusion Injury*

BACKGROUND: Unlike 99mTc-Sestamibi, microbubbles used during myocardial contrast echocardiography (MCE) exist only in the vascular space. Therefore, there may be a difference in the pattern of myocardial perfusion between MCE and 99mTc-Sestamibi Single-Photon Emission Computed Tomography (SPECT) in acute myocardial infarction (AMI). OBJECTIVES: The purpose of this study was to assess myocardial perfusion using MCE with intravenous infusion of perfluorocarbon-exposed sonicated dextrose albumin microbubbles (IV MCE), and to compare it with SPECT and MCE with intracoronary injection of sonicated Hexabrix (IC MCE). METHODS: Seventeen patients with AMI (male 13, age 59.5+/-8.8 years, anterior MI 10) underwent IV MCE at 8.1+/-3.7 days after onset. SPECT and IC MCE were also performed at 1.2+/-1.0 days and 2.0+/-1.5 days from IV MCE respectively. Any revascularization procedures were not performed between three studies. Perfusion defect by three methods was scored semiquantitatively as 1 : normal perfusion, 0.5 : moderate defect, and 0 : severe defect at 16 segments of the left ventricle. RESULTS: 1) Perfusion defect in infarction territory was detected in 15 patients with SPECT, 12 patients with IV MCE and 11 patients with IC MCE. 2) Concordance of perfusion score at each segment was 93% between IV MCE and IC MCE, 65% between IV MCE and SPECT, and 64% between IC MCE and SPECT. 3) With IV MCE, perfusion defect was observed in all 32 segments which were considered as having defect (score 0 and 0.5) by IC MCE. However, defect by IV MCE was found only in 31 out of 108 segments considered as having defect by SPECT. CONCLUSION: In the assessment of myocardial perfusion in pts with AMI, IV MCE and IC MCE showed similar results. However, there was some discrepancy in the extent of perfusion defect between MCE studies and SPECT.
Echocardiography ; Glucose ; Heart Ventricles ; Humans ; Infarction ; Infusions, Intravenous ; Ioxaglic Acid ; Microbubbles ; Myocardial Infarction* ; Perfusion* ; Technetium Tc 99m Sestamibi ; Tomography, Emission-Computed ; Tomography, Emission-Computed, Single-Photon

BACKGROUND AND OBJECTIVES: The pathological findings of Non-Q wave myocardial infarction(NQMI) on ECG did not always correspond to subendocardial infarction(SEMI). The purpose of this study was to evaluate the diagnostic validity of ECG for SEMI by myocardial contrast echocardiography (MCE) in the patients with acute myocardial infarction(AMI). MATERIALS AND METHODS: The study population was 84 patients who underwent MCE under the diagnosis of AMI. MCE was performed by intracoronary injection of sonicated Hexabrix into the infarct related artery and SEMI was diagnosed by inspecting endocardial defect with epicardial enhancement on MCE. RESULTS: (1) Among 19 NQMI cases, 7 cases showed SEMI with MCE score 0.5, 11 cases with score 1, and 1 case with score 0. Among 65 Q-wave MI(QMI) cases, only 5 cases showed SEMI. (2) 7 cases who had NQMI with SEMI showed LV wall motion recovery at follow-up echocardiography except 1 case. Whereas, of 5 QMI cases who had SEMI, only 1 case improve LV wall motion. CONCLUSION: NQMI on ECG does not always imply SEMI on MCE, but the absence of pathologic Q wave in the patients with SEMI is thought to be a predictive factor of the recovery of LV wall motion.
Arteries ; Diagnosis ; Echocardiography* ; Electrocardiography* ; Follow-Up Studies ; Humans ; Infarction* ; Ioxaglic Acid

BACKGROUND AND OBJECTIVES: The pathological findings of Non-Q wave myocardial infarction(NQMI) on ECG did not always correspond to subendocardial infarction(SEMI). The purpose of this study was to evaluate the diagnostic validity of ECG for SEMI by myocardial contrast echocardiography (MCE) in the patients with acute myocardial infarction(AMI). MATERIALS AND METHODS: The study population was 84 patients who underwent MCE under the diagnosis of AMI. MCE was performed by intracoronary injection of sonicated Hexabrix into the infarct related artery and SEMI was diagnosed by inspecting endocardial defect with epicardial enhancement on MCE. RESULTS: (1) Among 19 NQMI cases, 7 cases showed SEMI with MCE score 0.5, 11 cases with score 1, and 1 case with score 0. Among 65 Q-wave MI(QMI) cases, only 5 cases showed SEMI. (2) 7 cases who had NQMI with SEMI showed LV wall motion recovery at follow-up echocardiography except 1 case. Whereas, of 5 QMI cases who had SEMI, only 1 case improve LV wall motion. CONCLUSION: NQMI on ECG does not always imply SEMI on MCE, but the absence of pathologic Q wave in the patients with SEMI is thought to be a predictive factor of the recovery of LV wall motion.
Arteries ; Diagnosis ; Echocardiography* ; Electrocardiography* ; Follow-Up Studies ; Humans ; Infarction* ; Ioxaglic Acid

BACKGROUND: A collateral flow can be assessed and graded by coronary angiography, however, the technique does not provide any information about perfusion. Myocardial contrast echocardiography (MCE) can assess collateral perfusion and has superior spatial resolution in defining its distribution. OBJECTIVE: To investigate the difference of transmural perfusion according to the angiographical collateral grade in normal myocardium, we performed MCE of collateral artery in 16 patients (m : f = 11 : 5, age: 57+/-13yrs.) with angina and compared the results with the angiographical grades. METHODS: In six patients with preexisting collaterals on baseline angiography, we performed MCE after intracoronary injection of sonicated Hexabrix. For 10 patients without preexisting collaterals on baseline angiography, we performed angiography, MCE for recruited collateral arteries during balloon inflation of stenotic coronary arteries (2 times for 120sec.). For 12 patients who underwent PTCA, we performed pressure wire simultaneously with angiography and MCE for recruited collateral arteries during balloon inflation. Fractional collateral flow(FCF) was defined by the ratio of coronary wedge pressure to proximal pressure(Pw/Pa). Angiographical collaterals were graded according to 'Rentrop' criteria(grade 0-3). Transmural thickness (TMT) and enhanced myocardial thickness (EMT) of an enhanced segment on MCE were measured at diastolic phase. The depth of collateral perfusion was estimated by collateral perfusion index (CPI) that was the ratio of EMT to TMT. RESULTS: There were significant differences of CPI with respect to angiographical grades according to one way ANOVA test (p< 0.05). One of five patients who had no recruited collaterals showed partial enhancement confined to the epicardium with CPI of 0.24. There was significant correlation between the angiographical grade and the CPI with Spearman's Rho value of 0.93(p< 0.0001). The angiographical grades were significantly correlated with FCF with the Spearman's Rho value of 0.87(p=0.0002). There was also significant correlation between FCF and CPI with Pearson's r=0.81 (p=0.0016). CONCLUSION: The higher the angiographical collateral grade is, the higher the collateral pressure and the deeper the fractional transmural perfusion from epicardium into endocardium gets.
Angiography ; Arteries ; Coronary Angiography* ; Coronary Vessels ; Echocardiography* ; Endocardium ; Humans ; Inflation, Economic ; Ioxaglic Acid ; Myocardium ; Perfusion* ; Pericardium ; Pulmonary Wedge Pressure

PURPOSE: To determine which contrast media are both efficient and safe for the imaging of airways. MATERIALS AND METHODS: We evaluated five contrast media (barium, gastrografin, iotrolan, ioxaglate, iopentol) in terms of image quality and their effects on the lungs of 25 white rabbits. For bronchography 0.5ml of contrast media was used. In each contrast group, HRCT scans were obtained immediately (n=5), 12 hours (n=4), 1 day (n=3), 2 days (n=2), and 1 week (n=1) after bronchography. Histopathologic specimens were obtained immediately, 12 hours, 1 day, 2 days, and 1 week later. Bronchograms were evaluated for image quality by three radiologists working independently, and were scored as 1(poor), 2(moderate), or 3(good) in terms of contrast quality and bronchial coating. HRCT was evaluated by two radiologists who reached a concensus; they determined the presence of contrast media, and then the pattern and extent of pulmonary opacity, and any related changes. Histopatholgic specimens were evaluated by two pathologists who sought consensus as to the extent of inflammation, pulmonary edema, and hemorrhage, and any changes in these aspects. RESULTS: Bronchography indicated that the sum of scores for contrast quality was 45 for barium, 33 for gastrografin, 28 for iotrolan, 30 for ioxaglate, and 28 for iopentol, while for each of these media, the sum of scores for bronchial coating was 39, 19, 25, 23, and 21, respectively. Barium showed the best image quality. In all rabbits, HRCT demonstrated the variable extent of groundglass attenuation and/or consolidation. Lesions were most extensive at 1-2 days and then regressed at 1 week; these HRCT findings correlated well with histologic findings. In histologic studies of all five contrast media groups, variable severe inflammatory reactions were observed, with or without necrosis, congestion, edema, and hemorrhage. It was noted that ioxaglate appeared to cause least tissue reaction. CONCLUSIONS: The imaging results of this experimental study indicate that for bronchography, barium is the best available contrast media, On the basis of the histologic and HRCT results, however, ioxaglate is the best.
Barium ; Bronchography* ; Consensus ; Contrast Media* ; Diatrizoate Meglumine ; Edema ; Estrogens, Conjugated (USP) ; Hemorrhage ; Ioxaglic Acid ; Lung ; Necrosis ; Pneumonia ; Rabbits

BACKGROUND: It is well known that collateral circulation has important roles in ischemic heart diseases. The method most commonly used at present to evaluate collateral flow is coronary angiography. However, there are debates about the functional significance of angiographically visible collaterals because angiography visualizes only vessels that are larger than 100um in diameter. Recent studies suggest that myocardial contrast echocardiography (MCE) is a useful method in assessing collateral flow because it uses small microvascular tracers (4-12um) as a contrast agent. By using MCE, this study evaluates the role of angiographically visible collaterals in patients with acute myocardial infarction (AMI) and chronic ischemic heart disease. METHOD: Forty-one patients who underwent coronary angiography and MCE were included in this study (22 patients with acute myocardial infarction and 19 patients with chronic ischemic heart disease). Antegrade coronary flow was less than TIMI 3 flow in all patients. Myocardial perfusion through collaterals with MCE was evaluated by injecting sonicated Hexabrix into nonobstructing coronary arteries. Angiographically visualized collateral vessels were analysed as four grades and compared with the degree of myocardial opacification by MCE through collateral vessels. RESULT: Angiographic collaterals were frequently observed in patients with AMI and chronic ischemic heart disease with< or = TIMI 2 flow . There was poor correlation between TIMI grade and the grade of collaterals by angiography in AMI (r--0.29, p-0.20) and chronic ischemic heart disease (r--0.31, p-0.19). There was no correlation between collateral grades and myocardial opacification by MCE through collateral vessels in AMI (r-0.07, p-NS) and chronic ischemic heart disease (r-0.10, p-NS). In patients with relatively well developed collaterals (Grade II or III), the ischemic zone was perfused better through collateral flow in the chronic ischemic heart disease group than in the AMI group (Mean Retrograde Opacification Index 0.84+/-0.23 vs 0.32+/-0.22, p<0A65A>0.05). CONCLUSION: The study suggests that the role of angiographically visible collaterals is different in chronic ischemic heart disease and acute myocardial infarction. The grade of angiographically visible collaterals does not imply the extent of perfusion to myocardum at risk through collateral vessels.
Angiography ; Collateral Circulation ; Coronary Angiography ; Coronary Vessels ; Echocardiography ; Heart ; Humans ; Ioxaglic Acid ; Myocardial Infarction ; Myocardial Ischemia* ; Perfusion*

BACKGROUND: It has been demonstrated that within 2 weeks following acute myocardial infarction (AMI), exercise-induced ST-segment depression (STD) indicates subendocardial ischemia in the viable myocardium within infarcted or remote area from the infarction. Exercise-induced ST-segment elevation (STE) in leads with abnormal Q wave is associated with left ventricular dysfunction or aneurysm rather than transmural ischemia. We studied whether each pattern of ST-segment shift on exercise ECG during recovery phase following AMI is correlated with the perfusion status of infarcted myocardium evaluated by myocardial contrast echocardiog-raphy (MCE), regardless of findings of coronary angiography (CAG). METHOD: Study population was consisted of 25 patients with AMI (anteior wall: 11 patients, inferior wall: 14 patients, mean age=57.3+/-8.9years). Patients underwent exercise ECG and coronary angiography at 10 days post-AMI. After CAG, sonicated Hexabrix was injected into both coronory arteries alternatively and 2-D echocardiography was taken in parasternal short axis, apical 4, and 2 chamber views. To analyze the echocardiographic image semiquantitively, left ventricle was divided into 20 segments and perfusion status was graded as good, partial, and no opacification. RESULT: All patients with exercise-induced STE (n=8) in Q-leads had patent infarcted-related artery and poor collaterals on CAG, which was associated with poor or no opacification of infarcted myocardium on MCE. Patients with exercise-induced STD (n=9) frequently had closed infarct-related artery (67%), but good opacification of infarcted myocardium was shown by retrograde perfusion via collaterals, which was commonly seen in patients with multivessel disease. CONCLUSION: In early recovery phase of acute myocardial infarction, exercise-induced ST elevation in Q leads was associated with poor perfusional status in infarcted myocardium, even with patent infarct-related artery on CAG, while exercise-induced ST depression was frequently seen in the good perfusional status despite of closed infarted-related artery, which was commonly observed in patients with multivessel disease.
Aneurysm ; Arteries ; Axis, Cervical Vertebra ; Coronary Angiography ; Depression ; Echocardiography ; Electrocardiography ; Heart Ventricles ; Humans ; Infarction ; Ioxaglic Acid ; Ischemia ; Myocardial Infarction* ; Myocardium* ; Perfusion* ; Ventricular Dysfunction, Left

BACKGROUND: It has been demonstrated that within 2 weeks following acute myocardial infarction (AMI), exercise-induced ST-segment depression (STD) indicates subendocardial ischemia in the viable myocardium within infarcted or remote area from the infarction. Exercise-induced ST-segment elevation (STE) in leads with abnormal Q wave is associated with left ventricular dysfunction or aneurysm rather than transmural ischemia. We studied whether each pattern of ST-segment shift on exercise ECG during recovery phase following AMI is correlated with the perfusion status of infarcted myocardium evaluated by myocardial contrast echocardiog-raphy (MCE), regardless of findings of coronary angiography (CAG). METHOD: Study population was consisted of 25 patients with AMI (anteior wall: 11 patients, inferior wall: 14 patients, mean age=57.3+/-8.9years). Patients underwent exercise ECG and coronary angiography at 10 days post-AMI. After CAG, sonicated Hexabrix was injected into both coronory arteries alternatively and 2-D echocardiography was taken in parasternal short axis, apical 4, and 2 chamber views. To analyze the echocardiographic image semiquantitively, left ventricle was divided into 20 segments and perfusion status was graded as good, partial, and no opacification. RESULT: All patients with exercise-induced STE (n=8) in Q-leads had patent infarcted-related artery and poor collaterals on CAG, which was associated with poor or no opacification of infarcted myocardium on MCE. Patients with exercise-induced STD (n=9) frequently had closed infarct-related artery (67%), but good opacification of infarcted myocardium was shown by retrograde perfusion via collaterals, which was commonly seen in patients with multivessel disease. CONCLUSION: In early recovery phase of acute myocardial infarction, exercise-induced ST elevation in Q leads was associated with poor perfusional status in infarcted myocardium, even with patent infarct-related artery on CAG, while exercise-induced ST depression was frequently seen in the good perfusional status despite of closed infarted-related artery, which was commonly observed in patients with multivessel disease.
Aneurysm ; Arteries ; Axis, Cervical Vertebra ; Coronary Angiography ; Depression ; Echocardiography ; Electrocardiography ; Heart Ventricles ; Humans ; Infarction ; Ioxaglic Acid ; Ischemia ; Myocardial Infarction* ; Myocardium* ; Perfusion* ; Ventricular Dysfunction, Left