The clinically applied value of myocardial perfusion and systolic function in patients with coronary artery disease after coronary artery bypass surgery using real-time myocardial contrast echocardiography (RT-MCE) ...The clinically applied value of myocardial perfusion and systolic function in patients with coronary artery disease after coronary artery bypass surgery using real-time myocardial contrast echocardiography (RT-MCE) combined with two-dimensional strain echocardiography was assessed. Twenty patients underwent intravenous RT-MCE by intravenous injections of SonoVue before and after coronary artery bypass surgery. Two-dimensional images were recorded from the left ventricular four-chamber view, two-chamber view and the apical view before, and two weeks and three months after coronary artery bypass surgery, and the peak systolic longitudinal strain was measured. The results showed that myocardial perfusion was significantly increased after coronary artery bypass surgery in about 71.6% segments. In the group that myocardial perfusion was improved, the peak systolic longitu- dinal strain three months after bypass surgery was significantly higher than that before operation [(-15.78±5.91)% vs (-10.45±8.31)%, P〈0.05]. However, the parameters did not change in the group without myocardial perfusion improvement [(-10.33±6.53)% vs (-9.41±6.09)%, P〉0.05]. It was concluded that whether or not the improvement of myocardial perfusion can mirror the recovery trend of regional systolic function, two-dimensional strain echocardiography can observe dynamic change of regional systolic function. The combination of myocardial perfusion with two-dimensional strain echocardiography can more accurately assess the curative effectiveness of coronary artery bypass surgery.展开更多
In order to evaluate the left ventricular remodeling in patients with myocardial infarction after revascularization with intravenous real-time myocardial contrast echocardiography (RT-MCE), intravenous RT-MCE was pe...In order to evaluate the left ventricular remodeling in patients with myocardial infarction after revascularization with intravenous real-time myocardial contrast echocardiography (RT-MCE), intravenous RT-MCE was performed on 20 patients with myocardial infarction before coronary revascularization. Follow-up echocardiography was performed 3 months after coronary revascularization. Segmental wall motion was assessed using 18-segment LV model and classified as normal, hypokinesis, akinesis and dyskinesis. Myocardial perfusion was assessed by visual interpretation and divided into 3 conditions: homogeneous opacification=l; partial or reduced opaciflcation or subendocardial contrast defect=2; constrast defect=3. Myocardial perfusion score index (MPSI) was calculated by dividing the total sum of contrast score by the total number of segments with abnormal wall motion. Twenty patients were classified into 2 groups according to the MPSI: MPSI≤I.5 as good myocardial perfusion, MPSI〉1.5 as poor myocardial perfusion. To assess the left ventricular remodeling, the following comparisons were carried out: (1) Comparisons of left ventricular ejection fraction (LVEF), left ventricular end-systolic volume (LVESV) and left ventricular end-diastolic volume (LVEDV) before and 3 months after revascularization in two groups;(2) Comparisons of LVEF, LVESV and LVEDV pre-revascularization between two groups and comparisons of these 3 months post-revascularization between two groups; (3) Comparisons of the differences in LVEF, LVESV and LVEDV between 3 months post-and pre-revascularization (ALVEF, ALVESV and ALVEDV) between two groups; (4) The linear regression analysis between ALVEF, ALVESV, ALVEDV and MPSI. The results showed that the LVEF obtained 3 months after revascularization in patients with MPSI〉1.5 was obviously lower than that in those with MPSI〈1.5. The LVEDV obtained 3 months post-revascularization in patients with MPSI〉1.5 was obviously larger than that in those with MPSI≤1.5 (P=0.002 and 0.04). The differences in ALVEF and ALVEDV between patients with MPSI〉I.5 and those with MPSI≤1.5 were significant (P=0.002 and 0.001, respectively). Linear regression analysis revealed that MPSI had a negative correlation with ALVEF and a positive correlation with ALVESV, ALVEDV (P=0.004, 0.008, and 0.016, respectively). It was concluded that RT-MCE could accurately evaluate the left ventricular remodeling in patients with myocardial infarction after revascularization.展开更多
To evaluate the feasibility of real-time myocardial contrast echocardiography (RTMCE) by quantitative analysis of myocardial perfusion in rabbits, transthoracic RTMCE was performed in 10 healthy rabbits by using con...To evaluate the feasibility of real-time myocardial contrast echocardiography (RTMCE) by quantitative analysis of myocardial perfusion in rabbits, transthoracic RTMCE was performed in 10 healthy rabbits by using continuous infusion of SonoVue into the auricular vein. The short axis view at the papillary muscle level was obtained. The duration of the time that the contrast took to appear in right heart, left heart and myocardium was recorded. The regional myocardial signal intensity (SI) versus re-filling time plots were fitted to an exponential function: y(t) =A(1–e–β(t–t0)) + C, where y is SI at any given time, A is the SI plateau that reflects myocardial blood volume, and β is the slope of the refilling curve that reflects myocardial microbubble velocity. The A, β and A×β values at different infusion rate of SonoVue were analyzed and the A, β and A×β values in each segment in the short axis view at the papillary muscle level were compared. All the animal experiments were successful and high-quality im-ages were obtained. The best intravenous infusion rate for SonoVue was 30 mL/h. The contrast appeared in right heart, left heart and myocardium at 7.5±2.2 s, 9.1±2.4 s and 12.2±1.6 s respectively. After 16.6±2.3s, myocardial opacification reached a steady state. The mean A, β and A×β value in the short axis view at the papillary muscle level were 9.8±3.0 dB, 1.4±0.5 s-1 and 13.5±3.6 dB×s-1 respectively. A, β and A×β values showed no significant differences among 6 segments. It was suggested that RTMCE was feasible for quantitative analysis of myocardial perfusion in rabbits. It provides a non-invasive method to evaluate the myocardial perfusion in rabbit disease models.展开更多
The myocardial viability after myocardial infarction was evaluated by intravenous myocardial contrast echocardiography. Intravenous real-time myocardial contrast echocardiography was performed on 18 patients with myoc...The myocardial viability after myocardial infarction was evaluated by intravenous myocardial contrast echocardiography. Intravenous real-time myocardial contrast echocardiography was performed on 18 patients with myocardial infarction before coronary revascularization. Follow-up echocardiography was performed 3 months after coronary revascularization. Segmental wall motion was assessed using 18-segment LV model and classified as normal, hypokinesis, akinesis and dyskinesis. Viable myocardium was defined by evident improvement of segmental wall motion 3 months after coronary revascularization. Myocardial perfusion was assessed by visual interpretation and divided into 3 conditions: homogeneous opacification; partial or reduced opaciflcation or subendocardial contrast defect; contrast defect. The former two conditions were used as the standard to define the viable myocardium. The results showed that 109 abnormal wall motion segments were detected among 18 patients with myocardial infarction, including 47 segments of hypokinesis, 56 segments of akinesis and 6 segments of dyskinesis. The wall motion of 2 segments with hypokinesis before coronary revascularization which showed homogeneous opacification, 14 of 24 segments with hypokinese and 20 of 24 segments with akinese before coronary revascularization which showed partial or reduced opaciflcation or subendocardial contrast defect was improved 3 months after coronary revascularization. In our study, the sensitivity and specificity of evaluation of myocardial viability after myocardial infarction by intravenous real-time myocardial contrast echocardiography were 94.7% and 78.9%, respectively. It was concluded that intravenous real-time myocardial contrast echocardiography could accurately evaluate myocardial viability after myocardial infarction.展开更多
Background Myocardial blood flow(MBF) can be quantified with myocardial contrast echocardiography (MCE) during a venous infusion of microbubble. A minimal MBF is required to maintain cell membrane integrity and myocar...Background Myocardial blood flow(MBF) can be quantified with myocardial contrast echocardiography (MCE) during a venous infusion of microbubble. A minimal MBF is required to maintain cell membrane integrity and myocardial viability in ischemic condition. Thus, we hypothesized that MCE could be used to assess myocardial viability by the determination of MBF. Methods and ResultsMCE was performed at 4 hours after ligation of proximal left anterior descending coronary artery in 7 dogs with constant venous infusions of microbubbles. The video intensity versus pulsing interval plots derived from each myocardial pixel were fitted to an exponential function: y=A(1-e-βt), where y is Ⅵ at pulsing interval t, A reflects microvascular cross - sectional area (or myocardial blood volume), and βreflects mean myocardial microbubble velocity. The product of A·β represents MBF. MBF was also obtained by ra-diolabeled microsphere method servered as reference. MBF derived by radiolabeled microsphere - method in the regions of normal, ischemia and infarction was 1.5+0.3, 0.7+0.3, 0. 3+0. 2 mL @ min-1@ g-1 respectively. The product of A·β obtained by MCE in those regions was 52. 46±15. 09, 24. 36±3. 89, 3. 74 ±3. 80 respectively. There was good correlation between normalized MBF and the normalized A·β ( r = 0. 81, P=0. 001). Conclusions MCE has an ability to determine myocardial viability in myocardial infarction canine model.展开更多
Here, a patient with chest pain and <50% stenosis on coronary angiography, where ATP stress myocardial contrast echocardiography (MCE) revealed that coronary flow reserve was reduced to 1.71 was presented. Perfusio...Here, a patient with chest pain and <50% stenosis on coronary angiography, where ATP stress myocardial contrast echocardiography (MCE) revealed that coronary flow reserve was reduced to 1.71 was presented. Perfusion delay occurred in the left ventricular wall of the apex of the heart before ATP stress, and the perfusion delay area was significantly reduced at peak stress. Similar to the characteristics of "reverse redistribution" of radionuclide myocardium perfusion in coronary vasospasm, the delayed perfusion area in the recovery period was larger than that detected before stress. Together with increased spectral resistance of the distal segment of left anterior descending coronary artery and chest pain, these findings indicated coronary microvascular disease with spasmodic characteristics in this patient. The perfusion characteristics on ATP stress determined by MCE and changes in coronary spectrum have value for the diagnosis and treatment of coronary microvascular disease with spasmodic characteristics.展开更多
Background Both real-time three-dimensional echocardi ography (RT3DE) and myocardial contrast echocardiography (MCE) are novel imaging techniques. The purpose of this study was to confirm the feasibility and accuracy ...Background Both real-time three-dimensional echocardi ography (RT3DE) and myocardial contrast echocardiography (MCE) are novel imaging techniques. The purpose of this study was to confirm the feasibility and accuracy of RT3DE combined with MCE for quantitative evaluation of myocardial perfusion defects. Methods Thirteen dogs underwent ligation of the left anterior descending artery (LAD, n=6) or distal branch of the left circumflex artery (LCX, n=7) under general anaesthesia. Three to four ml of a perfluoropropane (C 3F 8) microbubble contrast agent was injected intravenously to assess the resulting myocardial perfusion defects with a commercially available Philips SONOS-7500 ultrasound system. After removal of the dog hearts, Evans blue dye was injected via the left and righ t coronary arteries to stain the myocardium at risk. In vitro anatomic measurements of myocardial mass after removal of the animals’ hearts were used as control s. Results Left ventricular (LV) mass determined by RT3DE ranged 36.7-68.9 g [mean, (54.6±9.6) g] before coronary artery ligation, and correlated highly (r=0.99) with in vitro measurement of LV mass [range, 38.9-71.1 g; mean, (55.6±9.3) g]. There was no significant difference between RT3DE and in vitro measurements of LV mass [range, 36.7-68.9 g; mean, (51.3±12.5) g. Or range, 38.9-71. 1 g; mean, (53.7±12.3) g, respectively] and under-perfused mass [range, 0-21.4 g; mean, (12.0±6.9) g. Or range, 0-19.8 g; mean, (10.8±6.3) g, respectively] after th e LAD ligation (P>0.05). Likewise, no significant difference was present between RT3DE and in vitro measurements of LV mass [range, 50.1-65.4 g; mean, (57.5±5.9 ) g. Or range, 51.5-65.8 g; mean, (57.3±6.4) g, respectively] and under-perfused m ass [range, 0-25.6 g; mean, (13.3±9.6) g. Or range, 0-22.7 g; mean, (12.8±8.1 ) g, respectively] after the LCX ligation (P>0.05). For all the animals with coronary ligation, LV mass measured by RT3DE ranged 35.9-68.6 g [mean, (54.8±10.0) g] a nd there was no significant difference between RT3DE and in vitro measurements of LV mass and under-perfused mass (P>0.05, r=0.99). Further, the under-perfused mass derived from RT3DE [range, 0-25.6 g; mean, (12.7±8.2) g] correlate d strongly with the in vitro measurements [range, 0-22.7 g; mean, (11.9±7.2) g] ( r=0.96). Conclusion RT3DE with MCE is a rapid and accurate method for estimating LV myocardial mass and quantifying perfusion defects.展开更多
Background Time-intensity curves derived from microbubble destruction/refilling sequences and recorded using myocardial contrast echocardiography (MCE) can provide parameters that correlate with coronary blood flow. ...Background Time-intensity curves derived from microbubble destruction/refilling sequences and recorded using myocardial contrast echocardiography (MCE) can provide parameters that correlate with coronary blood flow. The response of these parameters to adenosine vasodilatation correlates with coronary flow reserve (CFR) measured by fluorescent microsphere techniques (FMT). Currently, no data exist regarding the effect of physiological variables, such as hypoxia, on the determination of CFR by MCE. The purpose of this study was to define the effects of decreases in blood partial pressure of oxygen (PO_2) on CFR as measured by MCE. Methods Studies were performed in 9 closed chest swine. Low-energy, real-time MCE was performed with commercial instruments in short axis view at papillary muscle level while infusing BR_1 at 30 ml/h. High-energy ultrasound bursts (referred to as FLASH frames) destroyed the bubbles every 15 cardiac cycles, and resultant time-intensity curves derived from these sequences were fitted to the exponential function y = A (1-e -bt) +c, from which the rate of signal rise (b) was obtained. CFR was calculated as the ratio of b values after adenosine infusion to baseline and was obtained during the control period and after decreasing blood PO_2 by giving nitrogen via a respirator to create artificial hypoxic conditions. CFR was independently determined by FMT. Results Nitrogen led to significant decreases in mean PO_2, from (120.6±18.9) mmHg to (51.8±15.9) mmHg (P<0.01). Adenosine produced a similar increase in CFR (2.5 fold vs 3.1 fold) as assessed by MCE and FMT during the control period. The decrease in PO_2 post nitrogen resulted in a slight increase in values at rest: 0.46±0.15 to 0.53±0.18 for b and (1.39±0.66) ml·min -1·g -1 to (1.72±0.30) ml·min -1·g -1 for myocardial blood flow (MBF) (both P<0.05). In addition, values decreased in response to adenosine using both techniques: 1.05±0.35 to 0.82±0.27 for b and (4.30±3.16) ml·min -1·g -1 to (3.93±1.27) ml·min -1·g -1 for MBF (both P<0.05). Thus, CFR was markedly reduced under hypoxic conditions, to 1.4 by MCE (P<0.05 compared with the baseline), and to 2.5 by FMT (P>05 compared with the baseline). Conclusions CFR values diminish under hypoxic conditions according to both MCE and FMT. The reductions in CFR involve both an increase in resting values and a decrease in post adenosine measurements, as determined by both techniques. The reduction in CFR under hypoxia is slightly greater using MCE than using FMT. Physiological variables, such as hypoxia, must be taken into consideration when assessing CFR by MCE.展开更多
Background Quantitatively assessing myocardial perfusion and its reserve is of great importance for the diagnosis and stratification of patients with coronary artery disease ( CAD), and represents an important goal ...Background Quantitatively assessing myocardial perfusion and its reserve is of great importance for the diagnosis and stratification of patients with coronary artery disease ( CAD), and represents an important goal of myocardial contrast echocardiography. In this study we sought to test the usefulness of low dose dobutamine stress real-time myocardial contrast echocardiography (RT-MCE) in the assessment of CAD, and to explore the relationship between perfusion reserve and contractile reserve. Methods Twenty-six patients with suspected or clinical diagnosed CAD were enrolled and underwent RT-MCE at baseline and under low dose dobutamine stress, and subsequent coronary angiography. RT-MCE images were analyzed quantitatively from microbubble replenishment curves for myocardial perfusion and its reserve. Results At baseline, significant differences in beta (0.28± 0. 12, 0. 25± 0. 09, 0.22 ± 0. 06, 0. 20± 0.07 respectively, P 〈0. 01) and A x beta (1.37 ±0. 46, 1.28±0. 47, 1. 13 ±0. 37, 0.91±0. 32, respectively, P 〈0. 01 ) were observed among four segment groups with graded coronary artery stenosis severity (normal; 30% -69% stenosis; 70% -90% stenosis; and beyond 90% stenosis) , but not observed in parameter A. When under stress, significant differences in A (5.73 ± 1.28, 5.63 ± 1.01,4.96 ±0.81,4.57 _+0.62, respectively, P〈0.01), beta (0.67 ±0. 17, 0.55 ±0. 19, 0.32 ±0. 13, 0.25 ±0.08, respectively, P 〈0.01) and A x beta (3.81 ± 1.20, 3. 11±1.17, 1.59 ±0. 82, 1. 12 _+0. 37, respectively, P 〈0. 01 ) were observed among the formerly mentioned groups. Graded decreases in A reserve ( 1.20 ±0. 53, 1.11 ±0. 16, 0.98 ±0. 12, 0. 99 ±0.13, respectively, P〈0.01), beta reserve (2.65 ±1.07, 2. 32±0.82, 1.44±0.40, 1.29±0.34, respectively, P〈0.01) and A xbeta reserve (3.05 ± 1.63, 2.59 ±1.01, 1.42 ±0.44, 1.27±0.34, respectively, P 〈 0. 01 ) could also be observed with increasing coronary stenosis severity. In five segments groups scored by WMS ( 1 - 5 ) , concordance between contractile function and myocardial perfusion could be found both at rest (beta: 0.28±0. 11, 0. 22 ±0. 08, 0. 21 ±0.05, 0. 17 ±0.05,0. 19 ±0.06, respectively, P 〈0.01; A xbeta: 1.29 ±0.48, 0.98 ±0.45, 0.94±0.29, 0.76 ±0.30, 0.92 ±0.32, respectively, P〈 0.01) and under stress (beta: 0.59 ±0.20, 0.35 ±0.15, 0.27 ±0.08, 0. 17±0.05, 0.20±0.05, respectively, P〈0.01; A xbeta: 3.07 ±1.38, 1.62±0.82, 1.28 ±0.40, 0.78 ±0.24, 0.93 v0.22, respectively, P 〈0. 01 ). This concordance is also valid in terms of the reserves, and the MCE parameters in segments with ameliorated contractile function are significantly higher than in those without. Conclusions Quantitative RT-MCE in conjunction with dobutamine stress shows promise in identifying and stratifying CAD and in exploring the perfusion-contractile correlation.展开更多
Background No-reflow is associated with an adverse outcome and higher mortality in patients with ST-segment elevation acute myocardial infarction (STEMI) who undergo percutaneous coronary intervention (PCI) and is...Background No-reflow is associated with an adverse outcome and higher mortality in patients with ST-segment elevation acute myocardial infarction (STEMI) who undergo percutaneous coronary intervention (PCI) and is considered a dynamic process characterized by multiple pathogenetic components. The aim of this study was to investigate the effectiveness of a combination therapy for the prevention of no-reflow in patient with acute myocardial infarction (AMI) undergoing primary PCI. Methods A total of 621 patients with STEMI who underwent emergency primary PCI were enrolled in this study. Patients with high risk of no-reflow (no-flow score 〉 10, by using a no-flow risk prediction model, n = 216) were randomly divided into a controlled group (n = 108) and a combination therapy group (n = 108). Patients in the controlled group received conventional treatment, while patients in combination therapy group received high-dose (80 mg) atorvastatin pre-treatment, intracoronary administration of adenosine (140 ~tg/min per kilogram) during PCI procedure, platelet membrane glycoprotein lib/Ilia receptor antagonist (tirofiban, 101.tg/kg bolus followed by 0.15 ~tg/kg per minute) and thrombus aspiration. Myocardial contrast echocardiography was performed to assess the myocardial perfusion 72 h after PCI. Major adverse cardiac events (MACE) were followed up for six months. Results Incidence of no-reflow in combination therapy group was 2.8%, which was similar to that in low risk group 2.7% and was significantly lower than that in control group (35.2%, P 〈 0.01). The myocardial perfusion (A= 13) values were higher in combination therapy group than that in control group 72 h after PCI. After 6 months, there were six (6.3%) MACE events (one death, two non-fatal MIs and three revasculafizations) in combination therapy group and 12 (13.2%) (four deaths, three non-fatal MIs and five revascularizations, P 〈 0.05) in control group. Conclusions Combination of thrombus aspiration, high-dose statin pre-treatment, intmcoronary administration of adenosine during PCI procedure and platelet membrane glycoprotein Ⅱ b/Ⅲa receptor antagonist reduces the incidence of no-reflow after primary PCI in patients with acute myocardial infarction who are at high risk of no-reflow.展开更多
This work is supported by Medical Science Technique Foundation of Guangdong Province.Abstract Objective To evaluate the newly developed perfluoropropene filled echo contrast agent (FCT 188) in non invasive assess...This work is supported by Medical Science Technique Foundation of Guangdong Province.Abstract Objective To evaluate the newly developed perfluoropropene filled echo contrast agent (FCT 188) in non invasive assessment of risk areas (RA) and infarct areas (IA) with intravenous myocardial contrast echocardiography (MCE) in canine model of ischemia followed by reperfusion. Methods Eight chest opened Beagle dogs with a 90 minute ischemia followed by a 240 minute reperfusion were studied. MCE was performed after a bolus injection of FCT 188 (0.025 ml/kg, Ⅳ) into a superficial vein of the forelimb at baseline, 20 minutes after occlusion, and 4 h after reperfusion to non invasively assess the left ventricular myocardium area (LVMA), myocardial ischemic risk area (RA), and infarct area (IA) in a short axis view of left ventricle. The accuracy of detecting myocardial perfusion with intravenous MCE was further assessed by in vitro myocardial staining of the matched cross sections. Both RA and IA were expressed as percent of LVMA. Results LVMA, RA, IA, and IA/RA ratio were accurately assessed by MCE (LVMA: 6.60 cm 2±0.76 cm 2; RA: 35.7%±6.68%; IA: 21.0%±13.2%; IA/RA: 60.3%±31.4%; n=7) as compared with those of the matched cross section (LVMA: 6.81 cm 2±0.73 cm 2, P=0.062; RA: 35.3%±9.9%, P= 0.84; IA: 25.10%±14.5%, P=0.07; IA/RA: 68.0%±22.2%, P=0.28, respectively). There was a significant correlation of MCE assessed IA/RA ratio and its corresponding pathologiclly determined finding in vitro (Y=1.21X-21.6, r=0.73, P=0.015). No significant changes of electrocardiogram (ECG), mean artery pressures (MAP), pulmonary artery pressures (PAP), and pulmonary artery wedge pressures (PAWP) were found between pre and post intravenous injection of FCT 188 at each time point. Conclusion These indicate that FCT 188 can be used to assess risk areas and infarct areas accurately and non invasively with intravenous MCE in the canine model of a 90 minute ischemia followed by a 240 minute reperfusion and might have potential significance for non invasive assessment of myocardial reperfusion clinically.展开更多
Background Innovative advancements in ultrasound instrumentation present a number of imaging modalities for myocardial contrast echocardiography (MCE) in ischemic syndromes. How well they compare to each other in di...Background Innovative advancements in ultrasound instrumentation present a number of imaging modalities for myocardial contrast echocardiography (MCE) in ischemic syndromes. How well they compare to each other in diagnostic accuracy in the detection of acute myocardial infarction is unclear. The purpose of this study was to assess the relative accuracy of 3 different imaging modes of MCE, low mechanical index (MI) real-time perfusion imaging (RTPI), triggered harmonic angio mode (HA), and ultraharmonic imaging mode (UH) in the detection of acute experimental myocardial infarction within the time frame suitable for potential reperfusion. Methods MCE was performed in 10 open-chest dogs using RTPI, triggered HA and triggered UH modes at baseline and one hour after occlusion of left anterior descending coronary artery. Presence or absence of peffusion defects, and the perfusion defect size when present, were analyzed and compared with the infarct size delineated by triphenyltetrazolium chloride (TTC) staining. Results The infarct area was (15.8-2.4)% by TTC staining; Peffusion defect area by MCE was similar to anatomic infarct area in all the three MCE approaches: (16.1-2.7)% by RTPI mode, (15.5-2.9)% by HA mode, and (15.5-3.0)% by UH mode. The sensitivity, specificity and overall diagnostic accuracy in the detection of myocardial infarction were 100%, 88%, and 94% for RTPI mode, 88%, 100%, and 94 % for HA mode, and 100%, 75%, and 88% for UH mode. Conclusion All modes of MCE, RTPI, triggered HA mode and triggered UH mode have excellent diagnostic accuracy in the immediate hour of acute coronary occlusion within the optimal time frame suitable for reperfusion therapy.展开更多
Background Myocardial perfusion associates with clinical syndromes and prognosis. Adenosine could improve myocardial perfusion of acute myocardial infarction within 6 hours, but few data are available on late perfusio...Background Myocardial perfusion associates with clinical syndromes and prognosis. Adenosine could improve myocardial perfusion of acute myocardial infarction within 6 hours, but few data are available on late perfusion of myocardial infarction (MI). This study aimed at quantitatively evaluating the value of intracoronary adenosine improving myocardial perfusion in late reperfused MI with myocardial contrast echocardiography (MCE). Methods Twenty-six patients with anterior wall infarcts were divided randomly into 2 groups: adenosine group (n=12) and normal saline group (n=-14). Their history of myocardial infarction was about 3-12 weeks. Adenosine or normal saline was given when the guiding wire crossed the lesion through percutaneous coronary intervention (PCI), then the balloon was dilated and stent (Cypher/Cypher select) was implanted at the lesion. Contrast pulse sequencing MCE with Sonovue contrast via the coronary route was done before PCI and 30 minutes after PCI. Video densitometry and contrast filled-blank area were calculated with the CUSQ off-line software. Heart function and cardiac events were followed up within 30 days. Results Perfusion in the segments of the criminal occlusive coronary artery in the adenosine group was better than that in the saline group (5.71:L-0.29 VS 4.95±1.22, P〈0.05). Ischemic myocardial segment was deminished significantly after PCI, but the meliorated area was bigger in the adenosine group than in the saline group ((1.56±0.60) cm^2 vs (1.02±0.56) cm^2, P〈0.05). The video densitometry in cntical segments was also improved significantly in the adenosine group (5.53±0.36 VS 5.26±0.35, P〈0.05). Left ventricular ejection fraction (LVEF) was improved in all patients after PCI, but EF was not significant between the two groups ((67±6)% vs (62±7)%, P〉0.05). There was no in-hospital or 30-day major adverse cardiac event (MACE) in the adenosine group but 3 MACE in the saline group in 30 days after PCI. Conclusions Adenosine could improve myocardial microvascular perfusion in the late reopening of an occluded infarct related artery (3 to 12 weeks after AMI) and clinical outcome in the follow-up period, and myocardial microvascular perfusion is a powerful predictor of clinical events.展开更多
文摘The clinically applied value of myocardial perfusion and systolic function in patients with coronary artery disease after coronary artery bypass surgery using real-time myocardial contrast echocardiography (RT-MCE) combined with two-dimensional strain echocardiography was assessed. Twenty patients underwent intravenous RT-MCE by intravenous injections of SonoVue before and after coronary artery bypass surgery. Two-dimensional images were recorded from the left ventricular four-chamber view, two-chamber view and the apical view before, and two weeks and three months after coronary artery bypass surgery, and the peak systolic longitudinal strain was measured. The results showed that myocardial perfusion was significantly increased after coronary artery bypass surgery in about 71.6% segments. In the group that myocardial perfusion was improved, the peak systolic longitu- dinal strain three months after bypass surgery was significantly higher than that before operation [(-15.78±5.91)% vs (-10.45±8.31)%, P〈0.05]. However, the parameters did not change in the group without myocardial perfusion improvement [(-10.33±6.53)% vs (-9.41±6.09)%, P〉0.05]. It was concluded that whether or not the improvement of myocardial perfusion can mirror the recovery trend of regional systolic function, two-dimensional strain echocardiography can observe dynamic change of regional systolic function. The combination of myocardial perfusion with two-dimensional strain echocardiography can more accurately assess the curative effectiveness of coronary artery bypass surgery.
文摘In order to evaluate the left ventricular remodeling in patients with myocardial infarction after revascularization with intravenous real-time myocardial contrast echocardiography (RT-MCE), intravenous RT-MCE was performed on 20 patients with myocardial infarction before coronary revascularization. Follow-up echocardiography was performed 3 months after coronary revascularization. Segmental wall motion was assessed using 18-segment LV model and classified as normal, hypokinesis, akinesis and dyskinesis. Myocardial perfusion was assessed by visual interpretation and divided into 3 conditions: homogeneous opacification=l; partial or reduced opaciflcation or subendocardial contrast defect=2; constrast defect=3. Myocardial perfusion score index (MPSI) was calculated by dividing the total sum of contrast score by the total number of segments with abnormal wall motion. Twenty patients were classified into 2 groups according to the MPSI: MPSI≤I.5 as good myocardial perfusion, MPSI〉1.5 as poor myocardial perfusion. To assess the left ventricular remodeling, the following comparisons were carried out: (1) Comparisons of left ventricular ejection fraction (LVEF), left ventricular end-systolic volume (LVESV) and left ventricular end-diastolic volume (LVEDV) before and 3 months after revascularization in two groups;(2) Comparisons of LVEF, LVESV and LVEDV pre-revascularization between two groups and comparisons of these 3 months post-revascularization between two groups; (3) Comparisons of the differences in LVEF, LVESV and LVEDV between 3 months post-and pre-revascularization (ALVEF, ALVESV and ALVEDV) between two groups; (4) The linear regression analysis between ALVEF, ALVESV, ALVEDV and MPSI. The results showed that the LVEF obtained 3 months after revascularization in patients with MPSI〉1.5 was obviously lower than that in those with MPSI〈1.5. The LVEDV obtained 3 months post-revascularization in patients with MPSI〉1.5 was obviously larger than that in those with MPSI≤1.5 (P=0.002 and 0.04). The differences in ALVEF and ALVEDV between patients with MPSI〉I.5 and those with MPSI≤1.5 were significant (P=0.002 and 0.001, respectively). Linear regression analysis revealed that MPSI had a negative correlation with ALVEF and a positive correlation with ALVESV, ALVEDV (P=0.004, 0.008, and 0.016, respectively). It was concluded that RT-MCE could accurately evaluate the left ventricular remodeling in patients with myocardial infarction after revascularization.
文摘To evaluate the feasibility of real-time myocardial contrast echocardiography (RTMCE) by quantitative analysis of myocardial perfusion in rabbits, transthoracic RTMCE was performed in 10 healthy rabbits by using continuous infusion of SonoVue into the auricular vein. The short axis view at the papillary muscle level was obtained. The duration of the time that the contrast took to appear in right heart, left heart and myocardium was recorded. The regional myocardial signal intensity (SI) versus re-filling time plots were fitted to an exponential function: y(t) =A(1–e–β(t–t0)) + C, where y is SI at any given time, A is the SI plateau that reflects myocardial blood volume, and β is the slope of the refilling curve that reflects myocardial microbubble velocity. The A, β and A×β values at different infusion rate of SonoVue were analyzed and the A, β and A×β values in each segment in the short axis view at the papillary muscle level were compared. All the animal experiments were successful and high-quality im-ages were obtained. The best intravenous infusion rate for SonoVue was 30 mL/h. The contrast appeared in right heart, left heart and myocardium at 7.5±2.2 s, 9.1±2.4 s and 12.2±1.6 s respectively. After 16.6±2.3s, myocardial opacification reached a steady state. The mean A, β and A×β value in the short axis view at the papillary muscle level were 9.8±3.0 dB, 1.4±0.5 s-1 and 13.5±3.6 dB×s-1 respectively. A, β and A×β values showed no significant differences among 6 segments. It was suggested that RTMCE was feasible for quantitative analysis of myocardial perfusion in rabbits. It provides a non-invasive method to evaluate the myocardial perfusion in rabbit disease models.
文摘The myocardial viability after myocardial infarction was evaluated by intravenous myocardial contrast echocardiography. Intravenous real-time myocardial contrast echocardiography was performed on 18 patients with myocardial infarction before coronary revascularization. Follow-up echocardiography was performed 3 months after coronary revascularization. Segmental wall motion was assessed using 18-segment LV model and classified as normal, hypokinesis, akinesis and dyskinesis. Viable myocardium was defined by evident improvement of segmental wall motion 3 months after coronary revascularization. Myocardial perfusion was assessed by visual interpretation and divided into 3 conditions: homogeneous opacification; partial or reduced opaciflcation or subendocardial contrast defect; contrast defect. The former two conditions were used as the standard to define the viable myocardium. The results showed that 109 abnormal wall motion segments were detected among 18 patients with myocardial infarction, including 47 segments of hypokinesis, 56 segments of akinesis and 6 segments of dyskinesis. The wall motion of 2 segments with hypokinesis before coronary revascularization which showed homogeneous opacification, 14 of 24 segments with hypokinese and 20 of 24 segments with akinese before coronary revascularization which showed partial or reduced opaciflcation or subendocardial contrast defect was improved 3 months after coronary revascularization. In our study, the sensitivity and specificity of evaluation of myocardial viability after myocardial infarction by intravenous real-time myocardial contrast echocardiography were 94.7% and 78.9%, respectively. It was concluded that intravenous real-time myocardial contrast echocardiography could accurately evaluate myocardial viability after myocardial infarction.
基金This work was supported in part by grants from thescience and technology foundation of China(39870329).
文摘Background Myocardial blood flow(MBF) can be quantified with myocardial contrast echocardiography (MCE) during a venous infusion of microbubble. A minimal MBF is required to maintain cell membrane integrity and myocardial viability in ischemic condition. Thus, we hypothesized that MCE could be used to assess myocardial viability by the determination of MBF. Methods and ResultsMCE was performed at 4 hours after ligation of proximal left anterior descending coronary artery in 7 dogs with constant venous infusions of microbubbles. The video intensity versus pulsing interval plots derived from each myocardial pixel were fitted to an exponential function: y=A(1-e-βt), where y is Ⅵ at pulsing interval t, A reflects microvascular cross - sectional area (or myocardial blood volume), and βreflects mean myocardial microbubble velocity. The product of A·β represents MBF. MBF was also obtained by ra-diolabeled microsphere method servered as reference. MBF derived by radiolabeled microsphere - method in the regions of normal, ischemia and infarction was 1.5+0.3, 0.7+0.3, 0. 3+0. 2 mL @ min-1@ g-1 respectively. The product of A·β obtained by MCE in those regions was 52. 46±15. 09, 24. 36±3. 89, 3. 74 ±3. 80 respectively. There was good correlation between normalized MBF and the normalized A·β ( r = 0. 81, P=0. 001). Conclusions MCE has an ability to determine myocardial viability in myocardial infarction canine model.
基金supported by the Sichuan Provincial Science and Technology Department Funds of China (2019YFS0436).
文摘Here, a patient with chest pain and <50% stenosis on coronary angiography, where ATP stress myocardial contrast echocardiography (MCE) revealed that coronary flow reserve was reduced to 1.71 was presented. Perfusion delay occurred in the left ventricular wall of the apex of the heart before ATP stress, and the perfusion delay area was significantly reduced at peak stress. Similar to the characteristics of "reverse redistribution" of radionuclide myocardium perfusion in coronary vasospasm, the delayed perfusion area in the recovery period was larger than that detected before stress. Together with increased spectral resistance of the distal segment of left anterior descending coronary artery and chest pain, these findings indicated coronary microvascular disease with spasmodic characteristics in this patient. The perfusion characteristics on ATP stress determined by MCE and changes in coronary spectrum have value for the diagnosis and treatment of coronary microvascular disease with spasmodic characteristics.
文摘Background Both real-time three-dimensional echocardi ography (RT3DE) and myocardial contrast echocardiography (MCE) are novel imaging techniques. The purpose of this study was to confirm the feasibility and accuracy of RT3DE combined with MCE for quantitative evaluation of myocardial perfusion defects. Methods Thirteen dogs underwent ligation of the left anterior descending artery (LAD, n=6) or distal branch of the left circumflex artery (LCX, n=7) under general anaesthesia. Three to four ml of a perfluoropropane (C 3F 8) microbubble contrast agent was injected intravenously to assess the resulting myocardial perfusion defects with a commercially available Philips SONOS-7500 ultrasound system. After removal of the dog hearts, Evans blue dye was injected via the left and righ t coronary arteries to stain the myocardium at risk. In vitro anatomic measurements of myocardial mass after removal of the animals’ hearts were used as control s. Results Left ventricular (LV) mass determined by RT3DE ranged 36.7-68.9 g [mean, (54.6±9.6) g] before coronary artery ligation, and correlated highly (r=0.99) with in vitro measurement of LV mass [range, 38.9-71.1 g; mean, (55.6±9.3) g]. There was no significant difference between RT3DE and in vitro measurements of LV mass [range, 36.7-68.9 g; mean, (51.3±12.5) g. Or range, 38.9-71. 1 g; mean, (53.7±12.3) g, respectively] and under-perfused mass [range, 0-21.4 g; mean, (12.0±6.9) g. Or range, 0-19.8 g; mean, (10.8±6.3) g, respectively] after th e LAD ligation (P>0.05). Likewise, no significant difference was present between RT3DE and in vitro measurements of LV mass [range, 50.1-65.4 g; mean, (57.5±5.9 ) g. Or range, 51.5-65.8 g; mean, (57.3±6.4) g, respectively] and under-perfused m ass [range, 0-25.6 g; mean, (13.3±9.6) g. Or range, 0-22.7 g; mean, (12.8±8.1 ) g, respectively] after the LCX ligation (P>0.05). For all the animals with coronary ligation, LV mass measured by RT3DE ranged 35.9-68.6 g [mean, (54.8±10.0) g] a nd there was no significant difference between RT3DE and in vitro measurements of LV mass and under-perfused mass (P>0.05, r=0.99). Further, the under-perfused mass derived from RT3DE [range, 0-25.6 g; mean, (12.7±8.2) g] correlate d strongly with the in vitro measurements [range, 0-22.7 g; mean, (11.9±7.2) g] ( r=0.96). Conclusion RT3DE with MCE is a rapid and accurate method for estimating LV myocardial mass and quantifying perfusion defects.
文摘Background Time-intensity curves derived from microbubble destruction/refilling sequences and recorded using myocardial contrast echocardiography (MCE) can provide parameters that correlate with coronary blood flow. The response of these parameters to adenosine vasodilatation correlates with coronary flow reserve (CFR) measured by fluorescent microsphere techniques (FMT). Currently, no data exist regarding the effect of physiological variables, such as hypoxia, on the determination of CFR by MCE. The purpose of this study was to define the effects of decreases in blood partial pressure of oxygen (PO_2) on CFR as measured by MCE. Methods Studies were performed in 9 closed chest swine. Low-energy, real-time MCE was performed with commercial instruments in short axis view at papillary muscle level while infusing BR_1 at 30 ml/h. High-energy ultrasound bursts (referred to as FLASH frames) destroyed the bubbles every 15 cardiac cycles, and resultant time-intensity curves derived from these sequences were fitted to the exponential function y = A (1-e -bt) +c, from which the rate of signal rise (b) was obtained. CFR was calculated as the ratio of b values after adenosine infusion to baseline and was obtained during the control period and after decreasing blood PO_2 by giving nitrogen via a respirator to create artificial hypoxic conditions. CFR was independently determined by FMT. Results Nitrogen led to significant decreases in mean PO_2, from (120.6±18.9) mmHg to (51.8±15.9) mmHg (P<0.01). Adenosine produced a similar increase in CFR (2.5 fold vs 3.1 fold) as assessed by MCE and FMT during the control period. The decrease in PO_2 post nitrogen resulted in a slight increase in values at rest: 0.46±0.15 to 0.53±0.18 for b and (1.39±0.66) ml·min -1·g -1 to (1.72±0.30) ml·min -1·g -1 for myocardial blood flow (MBF) (both P<0.05). In addition, values decreased in response to adenosine using both techniques: 1.05±0.35 to 0.82±0.27 for b and (4.30±3.16) ml·min -1·g -1 to (3.93±1.27) ml·min -1·g -1 for MBF (both P<0.05). Thus, CFR was markedly reduced under hypoxic conditions, to 1.4 by MCE (P<0.05 compared with the baseline), and to 2.5 by FMT (P>05 compared with the baseline). Conclusions CFR values diminish under hypoxic conditions according to both MCE and FMT. The reductions in CFR involve both an increase in resting values and a decrease in post adenosine measurements, as determined by both techniques. The reduction in CFR under hypoxia is slightly greater using MCE than using FMT. Physiological variables, such as hypoxia, must be taken into consideration when assessing CFR by MCE.
文摘Background Quantitatively assessing myocardial perfusion and its reserve is of great importance for the diagnosis and stratification of patients with coronary artery disease ( CAD), and represents an important goal of myocardial contrast echocardiography. In this study we sought to test the usefulness of low dose dobutamine stress real-time myocardial contrast echocardiography (RT-MCE) in the assessment of CAD, and to explore the relationship between perfusion reserve and contractile reserve. Methods Twenty-six patients with suspected or clinical diagnosed CAD were enrolled and underwent RT-MCE at baseline and under low dose dobutamine stress, and subsequent coronary angiography. RT-MCE images were analyzed quantitatively from microbubble replenishment curves for myocardial perfusion and its reserve. Results At baseline, significant differences in beta (0.28± 0. 12, 0. 25± 0. 09, 0.22 ± 0. 06, 0. 20± 0.07 respectively, P 〈0. 01) and A x beta (1.37 ±0. 46, 1.28±0. 47, 1. 13 ±0. 37, 0.91±0. 32, respectively, P 〈0. 01 ) were observed among four segment groups with graded coronary artery stenosis severity (normal; 30% -69% stenosis; 70% -90% stenosis; and beyond 90% stenosis) , but not observed in parameter A. When under stress, significant differences in A (5.73 ± 1.28, 5.63 ± 1.01,4.96 ±0.81,4.57 _+0.62, respectively, P〈0.01), beta (0.67 ±0. 17, 0.55 ±0. 19, 0.32 ±0. 13, 0.25 ±0.08, respectively, P 〈0.01) and A x beta (3.81 ± 1.20, 3. 11±1.17, 1.59 ±0. 82, 1. 12 _+0. 37, respectively, P 〈0. 01 ) were observed among the formerly mentioned groups. Graded decreases in A reserve ( 1.20 ±0. 53, 1.11 ±0. 16, 0.98 ±0. 12, 0. 99 ±0.13, respectively, P〈0.01), beta reserve (2.65 ±1.07, 2. 32±0.82, 1.44±0.40, 1.29±0.34, respectively, P〈0.01) and A xbeta reserve (3.05 ± 1.63, 2.59 ±1.01, 1.42 ±0.44, 1.27±0.34, respectively, P 〈 0. 01 ) could also be observed with increasing coronary stenosis severity. In five segments groups scored by WMS ( 1 - 5 ) , concordance between contractile function and myocardial perfusion could be found both at rest (beta: 0.28±0. 11, 0. 22 ±0. 08, 0. 21 ±0.05, 0. 17 ±0.05,0. 19 ±0.06, respectively, P 〈0.01; A xbeta: 1.29 ±0.48, 0.98 ±0.45, 0.94±0.29, 0.76 ±0.30, 0.92 ±0.32, respectively, P〈 0.01) and under stress (beta: 0.59 ±0.20, 0.35 ±0.15, 0.27 ±0.08, 0. 17±0.05, 0.20±0.05, respectively, P〈0.01; A xbeta: 3.07 ±1.38, 1.62±0.82, 1.28 ±0.40, 0.78 ±0.24, 0.93 v0.22, respectively, P 〈0. 01 ). This concordance is also valid in terms of the reserves, and the MCE parameters in segments with ameliorated contractile function are significantly higher than in those without. Conclusions Quantitative RT-MCE in conjunction with dobutamine stress shows promise in identifying and stratifying CAD and in exploring the perfusion-contractile correlation.
文摘Background No-reflow is associated with an adverse outcome and higher mortality in patients with ST-segment elevation acute myocardial infarction (STEMI) who undergo percutaneous coronary intervention (PCI) and is considered a dynamic process characterized by multiple pathogenetic components. The aim of this study was to investigate the effectiveness of a combination therapy for the prevention of no-reflow in patient with acute myocardial infarction (AMI) undergoing primary PCI. Methods A total of 621 patients with STEMI who underwent emergency primary PCI were enrolled in this study. Patients with high risk of no-reflow (no-flow score 〉 10, by using a no-flow risk prediction model, n = 216) were randomly divided into a controlled group (n = 108) and a combination therapy group (n = 108). Patients in the controlled group received conventional treatment, while patients in combination therapy group received high-dose (80 mg) atorvastatin pre-treatment, intracoronary administration of adenosine (140 ~tg/min per kilogram) during PCI procedure, platelet membrane glycoprotein lib/Ilia receptor antagonist (tirofiban, 101.tg/kg bolus followed by 0.15 ~tg/kg per minute) and thrombus aspiration. Myocardial contrast echocardiography was performed to assess the myocardial perfusion 72 h after PCI. Major adverse cardiac events (MACE) were followed up for six months. Results Incidence of no-reflow in combination therapy group was 2.8%, which was similar to that in low risk group 2.7% and was significantly lower than that in control group (35.2%, P 〈 0.01). The myocardial perfusion (A= 13) values were higher in combination therapy group than that in control group 72 h after PCI. After 6 months, there were six (6.3%) MACE events (one death, two non-fatal MIs and three revasculafizations) in combination therapy group and 12 (13.2%) (four deaths, three non-fatal MIs and five revascularizations, P 〈 0.05) in control group. Conclusions Combination of thrombus aspiration, high-dose statin pre-treatment, intmcoronary administration of adenosine during PCI procedure and platelet membrane glycoprotein Ⅱ b/Ⅲa receptor antagonist reduces the incidence of no-reflow after primary PCI in patients with acute myocardial infarction who are at high risk of no-reflow.
文摘This work is supported by Medical Science Technique Foundation of Guangdong Province.Abstract Objective To evaluate the newly developed perfluoropropene filled echo contrast agent (FCT 188) in non invasive assessment of risk areas (RA) and infarct areas (IA) with intravenous myocardial contrast echocardiography (MCE) in canine model of ischemia followed by reperfusion. Methods Eight chest opened Beagle dogs with a 90 minute ischemia followed by a 240 minute reperfusion were studied. MCE was performed after a bolus injection of FCT 188 (0.025 ml/kg, Ⅳ) into a superficial vein of the forelimb at baseline, 20 minutes after occlusion, and 4 h after reperfusion to non invasively assess the left ventricular myocardium area (LVMA), myocardial ischemic risk area (RA), and infarct area (IA) in a short axis view of left ventricle. The accuracy of detecting myocardial perfusion with intravenous MCE was further assessed by in vitro myocardial staining of the matched cross sections. Both RA and IA were expressed as percent of LVMA. Results LVMA, RA, IA, and IA/RA ratio were accurately assessed by MCE (LVMA: 6.60 cm 2±0.76 cm 2; RA: 35.7%±6.68%; IA: 21.0%±13.2%; IA/RA: 60.3%±31.4%; n=7) as compared with those of the matched cross section (LVMA: 6.81 cm 2±0.73 cm 2, P=0.062; RA: 35.3%±9.9%, P= 0.84; IA: 25.10%±14.5%, P=0.07; IA/RA: 68.0%±22.2%, P=0.28, respectively). There was a significant correlation of MCE assessed IA/RA ratio and its corresponding pathologiclly determined finding in vitro (Y=1.21X-21.6, r=0.73, P=0.015). No significant changes of electrocardiogram (ECG), mean artery pressures (MAP), pulmonary artery pressures (PAP), and pulmonary artery wedge pressures (PAWP) were found between pre and post intravenous injection of FCT 188 at each time point. Conclusion These indicate that FCT 188 can be used to assess risk areas and infarct areas accurately and non invasively with intravenous MCE in the canine model of a 90 minute ischemia followed by a 240 minute reperfusion and might have potential significance for non invasive assessment of myocardial reperfusion clinically.
文摘Background Innovative advancements in ultrasound instrumentation present a number of imaging modalities for myocardial contrast echocardiography (MCE) in ischemic syndromes. How well they compare to each other in diagnostic accuracy in the detection of acute myocardial infarction is unclear. The purpose of this study was to assess the relative accuracy of 3 different imaging modes of MCE, low mechanical index (MI) real-time perfusion imaging (RTPI), triggered harmonic angio mode (HA), and ultraharmonic imaging mode (UH) in the detection of acute experimental myocardial infarction within the time frame suitable for potential reperfusion. Methods MCE was performed in 10 open-chest dogs using RTPI, triggered HA and triggered UH modes at baseline and one hour after occlusion of left anterior descending coronary artery. Presence or absence of peffusion defects, and the perfusion defect size when present, were analyzed and compared with the infarct size delineated by triphenyltetrazolium chloride (TTC) staining. Results The infarct area was (15.8-2.4)% by TTC staining; Peffusion defect area by MCE was similar to anatomic infarct area in all the three MCE approaches: (16.1-2.7)% by RTPI mode, (15.5-2.9)% by HA mode, and (15.5-3.0)% by UH mode. The sensitivity, specificity and overall diagnostic accuracy in the detection of myocardial infarction were 100%, 88%, and 94% for RTPI mode, 88%, 100%, and 94 % for HA mode, and 100%, 75%, and 88% for UH mode. Conclusion All modes of MCE, RTPI, triggered HA mode and triggered UH mode have excellent diagnostic accuracy in the immediate hour of acute coronary occlusion within the optimal time frame suitable for reperfusion therapy.
文摘Background Myocardial perfusion associates with clinical syndromes and prognosis. Adenosine could improve myocardial perfusion of acute myocardial infarction within 6 hours, but few data are available on late perfusion of myocardial infarction (MI). This study aimed at quantitatively evaluating the value of intracoronary adenosine improving myocardial perfusion in late reperfused MI with myocardial contrast echocardiography (MCE). Methods Twenty-six patients with anterior wall infarcts were divided randomly into 2 groups: adenosine group (n=12) and normal saline group (n=-14). Their history of myocardial infarction was about 3-12 weeks. Adenosine or normal saline was given when the guiding wire crossed the lesion through percutaneous coronary intervention (PCI), then the balloon was dilated and stent (Cypher/Cypher select) was implanted at the lesion. Contrast pulse sequencing MCE with Sonovue contrast via the coronary route was done before PCI and 30 minutes after PCI. Video densitometry and contrast filled-blank area were calculated with the CUSQ off-line software. Heart function and cardiac events were followed up within 30 days. Results Perfusion in the segments of the criminal occlusive coronary artery in the adenosine group was better than that in the saline group (5.71:L-0.29 VS 4.95±1.22, P〈0.05). Ischemic myocardial segment was deminished significantly after PCI, but the meliorated area was bigger in the adenosine group than in the saline group ((1.56±0.60) cm^2 vs (1.02±0.56) cm^2, P〈0.05). The video densitometry in cntical segments was also improved significantly in the adenosine group (5.53±0.36 VS 5.26±0.35, P〈0.05). Left ventricular ejection fraction (LVEF) was improved in all patients after PCI, but EF was not significant between the two groups ((67±6)% vs (62±7)%, P〉0.05). There was no in-hospital or 30-day major adverse cardiac event (MACE) in the adenosine group but 3 MACE in the saline group in 30 days after PCI. Conclusions Adenosine could improve myocardial microvascular perfusion in the late reopening of an occluded infarct related artery (3 to 12 weeks after AMI) and clinical outcome in the follow-up period, and myocardial microvascular perfusion is a powerful predictor of clinical events.