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1.
Contrast echocardiography by venous injection of Albunex was used to visualize apical filling abnormality in patients with heart failure. 1. Contrast echocardiography was serially performed in 24 patients with acute anterior myocardial infarction. Wall motion of the infarct region was better at any stage in patients without apical filling abnormality than in patients with that. Improvement of filling abnormality was observed prior to that of wall motion abnormality. 2. Influence of tachycardia was assessed on apical filling in 20 patients with old myocardial infarction during rapid atrial pacing. Stress contrast echocardiography evidenced that tachycardia deteriorates apical filling abnormality in patients with chronic heart failure. 3. The effect of amrinone on apical filling was assessed in 60 patients with chronic anterior myocardial infarction. Apical filling abnormality improved in 46% of patients after amrinone infusion. The improvement of apical filling abnormality was closely related to the reduction of preload and improvement of asynergy in the infarct area after amrinone. Both adjunctive therapy and anticoagulant therapy should be considered if apical filling abnormalities are observed by contrast echocardiography.  相似文献   

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A patient is described, who was examined 1 year after surgery for mandibular cyst diagnosed as radicular near the !5 tooth and for plasty of the secondary osseous cavity with hydroxyapatite granulate. X-Ray examination revealed a cystic cavity near the roots of teeth !234. Histologic examination of tissue fragments and the remainder of hydroxyapatite granulate, obtained by cystectomy, helped diagnose a primordial cyst. Intensive bone regeneration was observed at the site of hydroxyapatite granule accumulation and fusion of the new bone with the granules to form a solid osseogranular complex. The authors recommend hydroxyapatite ceramic granules for surgical treatment of minor and medium bone defects and for corrective bone plasty.  相似文献   

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BACKGROUND: Dobutamine stress echocardiography (DSE) and myocardial contrast echocardiography (MCE) can predict recovery of left ventricular function after myocardial infarction. DSE also has been shown to predict left ventricular functional recovery after revascularization in chronic ischemic heart disease, whereas MCE has not been evaluated in such patients. This study was performed to compare DSE and MCE in the prediction of left ventricular functional recovery after revascularization in patients with chronic ischemic heart disease. METHODS AND RESULTS: MCE and DSE were performed in 35 patients with chronic coronary artery disease and significant wall motion abnormalities (mean ejection fraction, 0.36 +/- 0.09). Regional wall motion was scored by use of a 16-segment model wherein 1 = normal or hyperkinetic, 2 = hypokinetic, 3 = akinetic, and 4 = dyskinetic. Each segment was evaluated for contractile reserve by DSE and perfusion by MCE. Revascularization (coronary artery bypass graft [n = 13] and percutaneous transluminal coronary angioplasty [n = 10]) was successful in 23 patients. Follow-up echocardiograms were done to assess wall motion 30 to 60 days later. In 238 segments with resting wall motion abnormalities, perfusion was more likely to present than contractile reserve (97% versus 91%, P < .02). Revascularization resulted in functional recovery in 77 of 95 hypokinetic segments (81%) but only 18 of 57 akinetic segments (32%, P < .0001). DSE and MCE were not significantly different in predicting functional recovery of hypokinetic segments. In akinetic segments, DSE and MCE had similar sensitivities (89% versus 94%, respectively) and negative predictive values (93% and 97%, respectively) in predicting functional recovery. However, DSE had a higher specificity (92% versus 67%, P < .02) and positive predictive value (85% versus 55%, P < .02) than MCE in predicting functional recovery. CONCLUSIONS: Both contractile reserve by DSE and perfusion by MCE are predictive of functional recovery in hypokinetic segments after coronary revascularization in patients with chronic coronary revascularization in patients with chronic coronary artery disease. In akinetic segments, myocardial perfusion by MCE may exist in segments that do not recover contractile function after revascularization. Thus, contractile reserve during low-dose dobutamine infusion is a better predictor of functional recovery after revascularization in akinetic segments than perfusion.  相似文献   

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The aim of this study was to evaluate the relation between myocardial perfusion and ST-segment changes in patients with acute myocardial infarction treated with successful direct angioplasty. Thirty-seven patients, successfully treated with direct angioplasty, underwent myocardial contrast echocardiography before and after angioplasty. The sum of ST-segment elevation divided by the number of the leads involved (ST-segment elevation index) was calculated at 1, 5, 10, 20, and 30 minutes after restoration of a Thrombolysis In Myocardial Infarction trial grade 3 flow. After recanalization, myocardial reperfusion within the risk area was observed in 26 patients, whereas a no-reflow phenomenon occurred in 11. In patients with myocardial reperfusion, the ST-segment elevation index progressively declined, whereas in patients with no reflow, no significant change was observed. Reduction of > or = 50% in the ST-segment elevation index occurred in 20 of the 26 patients with reflow and in 1 of the 11 with no reflow (p = 0.0002). An additional increase of > or = 30% in the ST-segment elevation index occurred in 3 patients with reflow and in 7 with no reflow (p = 0.003). Sensitivity, specificity, positive and negative predictive values, and accuracy of the reduction in the ST-segment elevation index for predicting microvascular reflow were 77%, 91%, 95%, 62%, and 81%, respectively. The corresponding values of the increase in ST-segment elevation index for predicting no reflow were 64%, 88%, 70%, 85%, and 81%, respectively. In conclusion, after successful angioplasty, different patterns of myocardial perfusion are associated with different ST-segment changes. Analysis of ST-segment changes predicts the degree of myocardial reperfusion.  相似文献   

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BACKGROUND: We hypothesized that by using our newly defined method of destroying microbubbles and measuring their rate of tissue replenishment, we could assess the transmural distribution of myocardial perfusion. METHODS AND RESULTS: We studied 12 dogs before and after creation of left anterior descending coronary artery stenoses both at rest and during hyperemia (n=62 stages). Microbubbles were administered as a constant infusion, and myocardial contrast echocardiography (MCE) was performed with the use of different pulsing intervals. The video intensity versus pulsing interval plots derived from each myocardial pixel were fitted to an exponential function: y=A(1-ebetat), where A reflects microvascular cross-sectional area (or myocardial blood volume), and beta reflects mean myocardial microbubble velocity. The product A . beta represents myocardial blood flow (MBF). Average values for these parameters were derived from the endocardial and epicardial regions of interest placed over the left anterior descending coronary artery bed. Radiolabeled microsphere-derived MBF was also measured from the same regions. There was poor correlation between radiolabeled microsphere-derived MBF and A-endocardial/epicardial ratios (EER) (r=0.46). The correlation with beta-EER was better (r=0. 69, P<0.01). The best correlation with radiolabeled microsphere-derived MBF-EER was noted with A . beta-EER (r=0.88, P<0. 01). CONCLUSIONS: The transmural distribution of myocardial perfusion can be accurately assessed with MCE with the use of our newly described method of tissue replenishment of microbubbles after their ultrasound-induced destruction. In the model studied, an uncoupling of the transmural distribution of MBF and myocardial blood volume was observed during reversal of the MBF-EER.  相似文献   

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BACKGROUND: The purpose of this study was to determine whether myocardial perfusion can be quantified with myocardial contrast echocardiography using left atrial (LA) injection of contrast. METHODS AND RESULTS: Based on a series of in vitro and in vivo experiments, the optimal dose of sonicated albumin microbubbles injected into the LA for establishing a linear relation between video intensity and blood volume in the anterior myocardium was determined. In 10 open-chest dogs, myocardial blood flow (MBF) was augmented by increasing myocardial blood volume (MBV) with an intravenous infusion of phenylephrine HCl. In the presence of this drug, left anterior descending artery stenosis was produced, followed by release of stenosis, to change MBF within the anterior myocardium. MBV was calculated by dividing radiolabeled microsphere-derived MBF by microbubble transit rate. There was close coupling between MBF and MBV in the anterior myocardium during LA injection of contrast (y = 1.0x-0.03, SEE = 1.07, r = .92, P < .001). An excellent correlation was also noted between background-subtracted peak video intensity and MBV (y = 0.24x + 0.73, SEE = 0.36, r = .88, P < .001). On multivariate analysis, background-subtracted peak video intensity correlated best with MBV. CONCLUSIONS: Myocardial perfusion can be quantified from time-intensity curves derived from the anterior myocardium after LA injection of contrast. Background-subtracted peak video intensity in this situation correlates closely with MBV. When MBV and MBF are closely coupled, such as during inotropic stimulation of the heart, background-subtracted peak video intensity also correlates closely with MBF. Since there are similarities in the models of LA and venous injections, these data indicate that it may be feasible to quantify myocardial perfusion with myocardial contrast echocardiography after venous injection of contrast.  相似文献   

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Preoperative myocardial ischemia seems to be a predictor of poor outcome when detected by electrocardiography, pulmonary capillary wedge/pressure measurement and echocardiography. It could be demonstrated, that regional wall motion abnormalities appear earlier and are more sensitive signs of myocardial ischemia than the ECG. Using intraoperative epicardial and transesophageal echocardiography, high quality 2-d echocardiographic images of the heart can be recorded. For monitoring of left ventricular function and wall motion the transesophageal approach is most often used. By the transesophageal approach the left ventricle can be scanned in the long axis and by the transgastric approach in cross sections. They correspond to the apical four-chamber and left parasternal cross sectional imaging of the heart. Using the transgastric approach in the papillary short axis view all segments representing the three coronary arteries can be imaged. Recording in this position have been found to be highly reproducible. Only localized ischemia of the apex of the ventricle may be missed. Methologically the rotation and translocation of the heart remain a problem using the cross section images of the heart. But the left ventricular papillary muscles and the septal-right ventricular boarders can be used as land marks. Wall motion is scored in five grades. In addition to the semiquantitative analysis also a quantitative calculation using computers is possible. Using the midd papillary short axis view in nearly 120 intraoperative transesophageal echocardiograms since 1989 analysis of the systolic wall thickening was possible in 73% of the patients. According to the literature review 87% of the patients undergoing coronary bypass surgery or non-cardiac surgery have signs of preoperative ischemia.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

10.
Reduction of the splenic volume by partial resection and collateral development after transposition are of potential value in the elective treatment of esophageal varices, hypersplenism and ascites. A study was performed on young Wistar rats. A simple animal model of extrahepatic portal hypertension was used, narrowing the portal vein to an outer diameter of one millimeter (PVS). One day, three weeks and seven weeks after this operation the portal venous pressure was elevated as compared with the sham-operated controls. The portal hypertension was statistically significant at week three (1.31 +/- 0.04 vs. 0.72 +/- 0.18 kPa, p = 0.01). Portocaval pressure gradient after partial resection of the spleen (SR) and intramuscular transposition (IMTrans) was compared with the pressure gradient after graded portal vein stenosis. Three weeks after intramuscular transposition portocaval pressure gradient was reduced (1.46 +/- 0.38 vs. 1.74 +/- 0.13 kPa, n.s.). This data supports the hypothesis that the portal venous high-pressure compartment and the systemic venous low-pressure compartment are maintained after development of natural shunts to the systemic circulation. In the following experiment different types of splenic transposition were tested and compared to each other and a normal control group or to rats with protal vein stenosis (PVS), respectively. After PVS, the animals were reoperated, an SR was performed and the wound surface of the spleen was transposed into the left abdominal wall subcutaneously (SCTrans) or intramuscularly (IMTrans) or to the left liver lobe (splenohepatoplasty, SHP), respectively. After three weeks the animals underwent measurements of organ weights, collections of blood samples and the spleen was investigated histologically. Blood cell counts were nearly normal but total serum protein, albumin and the colloid osmotic pressure were slightly diminished or significantly reduced (COP in the groups PVS + SR + IMTrans or SCTrans, p < 0.05) compared to the controls. Differences to the group with portal vein stenosis (PVS) were not significant. Serum protein electrophoresis after splenic transposition revealed an unobtrusive distribution pattern. Animals after SHP had the best increase in weight and high protein levels, but splenohepatic collateral development seemed sparse. Differences of plasma ammonium levels were statistically not significant, but some animals had elevated levels after transposition. Morphometry of routine-stained spleen specimens showed an intact immunoarchitecture of the transposed spleens.  相似文献   

11.
Persistently ischemic myocardium exhibits increased glucose uptake which may contribute to the preservation of myocardial function and viability. Little is known about the specific molecular events which are responsible for this increase in uptake. Therefore, we investigated whether myocardial ischemia induces the gene expression of the major cardiac facilitative glucose transporters, GLUT4 and GLUT1. We determined the expression of myocardial glucose transporter mRNAs and polypeptides after 6 h of regional ischemia in a dog model by semi-quantitative Northern blotting and immunoblotting. GLUT1 but not GLUT4 expression was significantly increased in both ischemic and non-ischemic regions from the experimental hearts when compared to surgical control and normal hearts. GLUT1 mRNA expression was increased 3.4-fold and GLUT1 polypeptide expression was increased 1.7-fold in ischemic hearts when compared to normal or surgical-control hearts. There were no significant regional differences in GLUT1 expression in either normal or ischemic hearts. However, there was a tendency for GLUT1 mRNA expression to be highest in the non-ischemic regions from the 6-h ischemia hearts. These findings suggest that myocardial ischemia induces a factor or factors which stimulate GLUT1 expression in non-ischemic as well as ischemic myocardial regions. Increased GLUT1 expression may play a role in augmenting glucose uptake during ischemia.  相似文献   

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We investigated the validity of Gradient recalled EPI(GRE-EPI) after bolus injection of contrast agent(Gadolinium 0.1 mmol/kg) to detect the ischemic zone of myocardium. Seven healthy volunteers and fifteen patients with coronary artery disease who had only one vessel disease more than 99% stenosis in AHA/ACC classification were studied. GRE-EPI was performed in a transaxial, long axis or short axis orientation of the left ventricle on a 1.5-T Signa Horizon Scanner. Images were obtained every heartbeat for 200 consecutive heartbeats. Contrast agent was injected into the antecubital vein in a bolus after 10 heartbeats. Signal intensity changes in the left ventricular blood and myocardium were measured during myocardial contrast perfusion study. In all healthy volunteers, signal intensity in myocardium was reduced by contrast agent following signal loss in the left ventricular blood and recovered with wash out of contrast agent. But in patients, reduction and recovery of signal intensity in the ischemic zone by contrast agent were significantly delayed and much less than that in the nonischemic zone. In conclusion, myocardial perfusion imaging with GRE-EPI was useful in evaluation of ischemic heart disease.  相似文献   

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It may be established that the complex cardiopulmonary functional diagnostics in patients with chronic ischaemic heart disease obtained the following essential results: 1. The ergometrically achieved total functional capacity is clearly decreased in all age groups compared with the healthy persons, the differences are highly significant. 2. The proof of a coronary insufficiency got by the electrocardiogram after work is to be regarded as a factor limiting the functional capacity. 3. 72% of the patients reveal under load a PAEDP increased more than the normal of 25 Torr. After exclusion of a respiratory insufficiency these findings must be regarded as a disturbed myocardial function. 4. Thus the increased PAEDP under load apart from the well-known triad (angina pectoris under load, decreased total functional capacity, pathological ECG after work) is a sensitive and decisive factor for proving the disturbed cardial function in chronic ischaemic heart disease.  相似文献   

15.
Therapeutic and prophylactic antiarrhythmic efficacy of sotalol hydrochloride (Sotahexal, "Hexal", Germany) and its effects in intracardiac hemodynamics and ECG parameters were evaluated in 95 patients with ischemic heart disease (IHD). The highest response to the drug was observed in ventricular extrasystoles, arterial flutter and fibrillation. Acute episodes of arrhythmia are managed by bolus administration of Sotahexal [correction of Hexal]. In this case greater risk of side effects exists. It is desirable to decide on the drug dose, mode of administration on the individual basis with due consideration of the risks and dangers which could be avoided in case of adequate instrumental control.  相似文献   

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The aim of this study was to assess the diagnostic and prognostic value of the presence and characteristics of ischemic electrocardiographic (ECG) changes during dipyridamole stress echocardiography. The ECG response in 178 patients with echocardiographic evidence of myocardial ischemia during dipyridamole stress testing was analyzed. ECG changes occurred in 105 patients (59%). Patients with ECG changes had a higher incidence of echocardiographic signs of ischemia at a low dose than patients with an unchanged electrocardiogram (50% vs 23%; p = 0.0002). Three-vessel and/or left main coronary artery disease (CAD) was found in 41% of patients with and in 21% of patients without ECG changes (p = 0.029). During follow-up (33 +/- 19 months), 30 cardiac events occurred: 10 deaths, 6 infarctions, and 14 unstable anginas. Coronary revascularization was performed in 48 patients with and in 17 patients without ECG changes (p = 0.0022). The univariate predictors of cardiac events were: presence of ischemia in > or =4 ECG leads (p = 0.0004), echocardiographic evidence of ischemia at a low dose (p = 0.0062), ST-segment shift on precordial leads (p = 0.0094), family history of CAD (p = 0.0115), coexistence of > or =3 cardiovascular risk factors (p = 0.0156), ST-segment depression (p = 0.0172), and ECG changes during testing (p = 0.0335). At Cox analysis, occurrence of ischemia at a low dose (odds ratio 3.0; 95% confidence interval 1.3 to 6.8) and the presence of ischemia in > or =4 ECG leads (odds ratio 3.5; 95% confidence interval 1.3 to 9.3) had an independent prognostic importance. In conclusion, the presence and characteristics of ischemic ECG changes are associated with more extensive CAD and worse prognostic outlook than are echocardiographic changes alone during dipyridamole stress echocardiography.  相似文献   

18.
BACKGROUND: We hypothesized that the persistence of albumin microbubbles within the myocardium during crystalloid cardioplegia (CP) infusion and ischemia-reperfusion (I-R) occurs because of endothelial injury. METHODS AND RESULTS: The myocardial transit rate of albumin microbubbles was measured in 18 dogs perfused with different CP solutions and in 12 dogs undergoing I-R. Electron microscopy with cationized ferritin labeling of the glycocalyx was performed in 9 additional dogs after CP perfusion and in 3 additional dogs undergoing I-R. Microbubble transit was markedly prolonged during crystalloid CP perfusion. The addition of whole blood to the CP solution accelerated the transit rate in a dose-dependent fashion (P<0.05), which was greater with venous than with arterial blood (P<0.05). The addition of plasma or red blood cells to CP solutions was less effective in improving transit rate than addition of whole blood (P<0.05). Microbubble transit rate was independent of the temperature, K+ content, pH, PO2, osmolality, viscosity, and flow rate of the perfusate. Similarly, a proportion of microbubbles persisted in the myocardium after I-R, which was related to the duration of ischemia (P<0.01) but not of reflow. Crystalloid CP perfusion and I-R resulted in extensive loss of the endothelial glycocalyx without other ultrastructural changes. This effect was partially reversed in the case of crystalloid CP when it was followed by blood CP. CONCLUSIONS: Sonicated albumin microbubbles persist within the myocardium in situations in which the endothelial glycocalyx is damaged. The measurement of the myocardial transit rate of albumin microbubbles may provide an in vivo assessment of endothelial glycocalyx damage.  相似文献   

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AIMS/BACKGROUND: The liver clears circulating plasma-kallikrein through a receptor-mediated endocytosis process: an initial fast phase is followed by a slow exponential phase. METHODS: To determine whether the clearance rate of plasma-kallikrein is affected during liver regeneration, we perfused isolated rat livers with rat plasma-kallikrein (rPK) at 0, 1, 2, 3 and 7 days after partial hepatectomy or sham operation. RESULTS: Liver regeneration was followed by the expression of the proliferating-cell nuclear antigen (PCNA) labeling index. The serum concentration of alpha2-macroglobulin, an acute phase protein in rats, was measured. At day 1, the fast phase of rPK clearance rate increased in hepatectomized rats when compared with day 0 (4.9+/-0.4 and 3.7+/-0.4 mU/g liver min, p<0.05). However, at day 2, the rPK fast phase clearance rate dropped significantly (2.6+/-0.2, p<0.05), when compared with day 1. No difference was found among the sham groups at different days of hepatectomy. These changes seem to be independent of the acute phase reaction. The regenerative liver weight increased continuously during the observation period. PCNA expression increased significantly after hepatectomy, with maximal PCNA-labeling indices at days 1 and 2, declining thereafter. CONCLUSION: The rPK fast phase clearance rate changes during liver regeneration, with a zenith occurring when PCNA labeling index is maximal (day 1) and a nadir occurring at the mitotic phase (day 2).  相似文献   

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