From 1997 July to 2003 April at Hospital 108, the study was carried out on 90 patients suspected of ischemia with chest pain or on ECG. Ultrasound dobutamin stress test was undertaken with infused initial doses of 5mcg/kg/min until reaching an expected heart rate depending on the ages. Results showed that ultrasound dobutamin stresst test is a diagnostic method of 96% of sensitivity, 84% of specificity and 91% of accuracy
Myocardial Ischemia ; ultrasonography ; Heart Diseases

Dobutamin stress test with echocardiography was performed on 90 suspected patients of heart ischemia, aged 59.6  9.5 years old, during 29.1  17.49 months of following from July 1997 to April 2003 at the Hospital N0108. Results showed that, the procedure reach a sensitivity of 96%, specificity of 84% and an accuracy of 91%
Ultrasonography ; Myocardial Ischemia ; Heart Diseases

At the Department of internal neurology of Cho Ray Hospital from Dec 2000 to Jan 2003. 130 patients with acute hemisphere cerebral ischemic stroke were studied. Among them, 34 patients could not evaluated by transcranial Doppler sonography, only 79 had transcranial Doppler sonography (TDS) results and MRI results, which confirmed cerebral infarctus. TDS found 30 normal cases, 28 cases with asymmetric indices reduced, 18 cases increased, 1 case of localized acceleration, 2 cases of obstructive cerebral artery in the side of clinical symptom. MRI found 17 normal cases, 62 cases of stricture of cerebral arteries. Sensitivity and specificity of TDS accounted for 74.2% and 82.4% in comparing with cerebro-vascularogramme made by MRI.
Cerebrovascular Accident ; Brain Ischemia ; Cerebral Angiography ; Ultrasonography, Doppler, Transcranial

Intravenous tissue plasminogen activator (TPA) improves patient chances to recover from stroke by inducing mostly partial recanalization of large intracranial thrombi. TPA activity can be enhanced with ultrasound including 2 MHz transcranial Doppler (TCD). TCD identifies residual blood flow signals around thrombi, and, by delivering mechanical pressure waves, exposes more thrombus surface to circulating TPA. The international multi-center CLOTBUST trial showed that ultrasound enhances thrombolytic activity of a drug in humans thereby confirming multi-disciplinary experimental research conducted worldwide for the past 30 years. In the CLOTBUST trial, the dramatic clinical recovery from stroke coupled with complete recanalization within 2 hours after TPA bolus occurred in 25% of patients treated with TPA+TCD compared to 8% who received TPA alone (p=0.02). Complete clearance of a thrombus and dramatic recovery of brain functions during treatment are feasible goals for ultrasound-enhanced thrombolysis that can lead to sustained recovery. An early boost in brain perfusion seen in the Target CLOTBUST group resulted in a trend of 13% more patients achieving favorable outcome at 3 months, subject for a pivotal trial. However, different results were achieved in a small TRUMBI trial and another study that used Transcranial Color-Coded Duplex Sonography (TCCD). Adverse bio-effects of mid-KHz (300) ultrasound promote bleeding, including brain areas not-affected by ischemia while exposure to multi-frequency / multi-element duplex ultrasound resulted in a trend towards higher risk of hemorrhagic transformations. To further enhance the ability of TPA to break up thrombi, current ongoing clinical trials include phase II studies of a single beam 2 MHz TCD with perflutren-lipid microspheres. Enhancement of intra-arterial TPA delivery is being clinically tested with 1.7-2.1 MHz pulsed wave ultrasound (EKOS catheter). Multi-national dose escalation studies of microspheres and the development of an operator independent ultrasound device are underway.
Brain ; Brain Ischemia* ; Hemorrhage ; Humans ; Ischemia ; Microspheres ; Perfusion ; Stroke ; Thrombosis ; Tissue Plasminogen Activator ; Ultrasonography*

Spontaneous coronary artery dissection (SCAD) is an uncommon cause of acute myocardial ischemia, which frequently presents as sudden death. The pathophysiology and treatment of SCAD have not been fully determined. Herein, a case of SCAD, manifesting as variant angina, which rapidly progressed during an ergonovine test, in which 3 drug-eluting stents were deployed using intravascular an ultrasound guidance, with an excellent immediate result, is reported.
Coronary Vessels* ; Death, Sudden ; Drug-Eluting Stents ; Ergonovine* ; Myocardial Ischemia ; Stents* ; Ultrasonography* ; Ultrasonography, Interventional

Treatment strategies for patients with coronary artery disease (CAD) should be based on objective evidence of inducible ischemia in the subtended myocardium to improve clinical outcomes, symptoms, and cost-effectiveness. Fractional flow reserve (FFR) is the most verified index to-date for invasively evaluating lesion-specific myocardial ischemia. Favorable results from large clinical trials that applied FFR-guided percutaneous coronary intervention (PCI) prompted changes in coronary revascularization guidelines to emphasize the importance of this ischemia-based strategy using invasive coronary physiology. However, the frequency of functional evaluations is lacking in daily practice, and visual assessment still dominates treatment decisions in CAD patients. Despite recent efforts to integrate functional and anatomical assessments for coronary stenosis, there is considerable discordance between the 2 modalities, and the diagnostic accuracy of simple parameters obtained from current imaging tools is not satisfactory to determine functional significance. Although evidence that supports or justifies anatomy-guided PCI is more limited, and FFR-guided PCI is currently recommended, it is important to be aware of conditions and factors that influence FFR for accurate interpretation and application. In this article, we review the limitations of the current anatomy-derived evaluation of the functional significance of coronary stenosis, detail considerations for the clinical utility of FFR, and discuss the importance of an integrated physiologic approach to determine treatment strategies for CAD patients.
Coronary Angiography ; Coronary Artery Disease ; Coronary Stenosis ; Humans ; Ischemia ; Myocardial Ischemia ; Myocardium ; Percutaneous Coronary Intervention ; Physiology ; Ultrasonography, Interventional

This study evaluated the application of quantitative tissue velocity imaging (QTVI) in assessing regional myocardial systolic and diastolic functions in dogs with acute subendocardial ischemia. Animal models of subendocardial ischemia were established by injecting microspheres (about 300 microm in diameter) into the proximal end of left circumflex coronary artery in 11 hybrid dogs through cannulation. Before and after embolization, two-dimensional echocardiography, QTVI and real-time myocardial contrast echocardiography (RT-MCE) via intravenous infusion of self-made microbubbles, were performed, respectively. The systolic segmental wall thickening and subendocardial myocardial longitudinal velocities of risk segments before and after embolization were compared by using paired t analysis. The regional myocardial video intensity versus contrast time could be fitted to an exponential function: y=A.(1-exp(-beta.t)), in which the product of A and beta provides a measure of myocardial blood flow. RT-MCE showed that subendocardial normalized A.beta was decreased markedly from 0.99+/-0.19 to 0.35+/-0.11 (P<0.05) in 28 left ventricular (LV) myocardial segments after embolization, including 6 basal and 9 middle segments of lateral wall (LW), 8 middle segments of posterior wall (PW) and 5 middle segments of inferior wall (IW). However, there was no statistically significant difference in subepicardial layer before and after embolization. Accordingly, the ratio of A.beta of subendocardial myocardium to subepicardial myocardium in these segments was significantly decreased from 1.10+/-0.10 to 0.31+/-0.07 (P<0.05). Although the systolic wall thickening did not change 5 min after the embolization in these ischemic segments (29%+/-3% vs 31%+/-5%, P>0.05), the longitudinal peak systolic velocities (Vs) and early-diastolic peak velocities (Ve) recorded by QTVI were declined significantly (P<0.05). Moreover, the subendocardial velocity curves during isovolumic relaxation predominantly showed positive waves, whereas they mainly showed negative waves before the embolization. This study demonstrates that QTVI can more sensitively and accurately detect abnormal regional myocardial function and post-systolic systole caused by acute subendocardial ischemia.
Contrast Media ; Echocardiography/*methods ; Endocardium/physiopathology ; Microbubbles ; Myocardial Contraction/physiology ; Myocardial Ischemia/etiology ; Myocardial Ischemia/*physiopathology ; Myocardial Ischemia/*ultrasonography ; Myocardium/pathology ; Ventricular Function, Left/*physiology

BACKGROUND: There is little data about the intravascular ultrasound (IVUS) findings in the patients with vasospastic angina, especially with respect to patterns of vascular remodeling. METHODS: Coronary spasm was documented by angiography and ECG evidence of ischemia in 36 patients after administration of ergonovine (cumulative doses up to 350 microgram). After relief of spasm using 1,000 microgram of intracoronary nitroglycerin, IVUS imaging was performed and analyzed using standard methodology. The 36 focal spasm sites were compared to the proximal and distal reference segments. RESULTS: The angiographic baseline minimum lumen diameter measured 1.78+/-0.66mm, which decreased to 0.66+/-0.38mm with ergonovine provocaton (p<0.0001), increased to 2.66+/-0.64mm after intracoronary nitroglycerin (p<0.0001 compared to baseline and post-ergonovine), and did not change after the IVUS imaging (2.66+/-0.63mm, p=.9). Coronary artery spasm was observed in angiographically normal segments in 6 patients and near normal segments (<10% angiographic diameter stenosis by visual estimate) in 30. Atherosclerotic lesions were observed at all coronary spasm sites; the mean plaque burden measured 56% at the spasm site and 35% at the reference site. The plaque composition of spasm site was hypoechoic in 31 and hyperechoic, noncalcific in 5; there was no calcium. Positive remodeling (spasm site arterial area>proximal reference) was present in 5; intermediate remodeling (proximal reference >spasm site >distal reference arterial area) was present in 7; and negative remodeling (spasm site arterial area Angiography ; Atherosclerosis ; Calcium ; Constriction, Pathologic ; Coronary Vessels ; Electrocardiography ; Ergonovine ; Humans ; Incidence ; Ischemia ; Nitroglycerin ; Spasm* ; Ultrasonography*

A clinical review of 34 cases of aortic dissection which were admitted to Yeungnam University hospital between March 1983 and April 1992. The results are as follows: 1. The peak incidence was in 5th, 6th decade and male to female ratio was 1.83:1. 2. The most common cause of aortic dissection was atherosclerosis and hypertension (79%). 3. The most common presenting symptom was pain (73%). but dyspnea, palpable mass, murmur, shock were also observed. 4. Abnormal electrocardiographic finding was myocardial ischemia in 6 cases, arrhythmia in 5 cases, LVH in 5 cases. 5. The X-ray findings showed abnormal aortic contour in 10 cases but normal X-ray finding was observed in 63% of DeBaKey Type III. 6. The most common diagnostic procedure was echocardiogram and abdominal Ultrasonography. 7. The mortality of all cases was 20%, operation mortality was 18% but no death of medically treatment in medical indication.
Arrhythmias, Cardiac ; Atherosclerosis ; Dyspnea ; Electrocardiography ; Female ; Humans ; Hypertension ; Incidence ; Male ; Mortality ; Myocardial Ischemia ; Shock ; Ultrasonography

BACKGROUND: Although myocardial contrast 2D echocardiography is a good method to diagnose and evaluate myocardial ischemia and reperfusion, it has required intracoronary or intra aortic root injection of contrast agent and furthemore, the degree of myocardial contrast produced is small. Second harmonic imaging which is based on the non linear emission of harmonics by resonant microbubble in the ultrasound field improves the ultrasound contrast single to noise ratio. METHODS: We measure the videointensity of interventricular septum(IVS) and lateral wall(LW) of second harmonic imaging myocardial contrast 2D echocardiography before and after LV injection of Levovist(300mg/ml, 0.4ml/Kg) in both pre and post left anterior descending coronary artery(LAD) ligation in 7 open chest pigs. RESULTS: 1) The mean(+/-SD) pre LAD ligation videointensity is significantly greater with after contrast than before contrast(IVS : 111.1+/-33.9 vs 31.1+/-7.6 ; p=0.00046, LW : 120.5+/-21.5 vs 42.2+/-10.0 ; p=0.00006). The post LAD ligation videointensity is also significantly greater with after contrast than before contrast(IVS : 62.8+/-24.6 vs 35.6+/-15.1 ; p=0.00379, LW : 129.9+/-10.9 vs 48.7+/-21.1 ; p=0.00006). 2) The videointensity of IVS is significantly greater with after contrast than before contrast in both pre and post LAD ligation(62.8+/-24.6 vs 111.1+/-33.9 ; p=0.0031). The post LAD ligation videointensity of LW after contrast is not different from that of pre LAD ligation(129.9+/-10.9 vs 120.5+/-21.5 ; p=0.1037). 3) The post LAD ligation videointensity increase of IVS is lower than pre LAD ligantion videointensity increase(27.2+/-18.3 vs 79.9+/-35.0 ; p=0.0006). But the videointensity increase of LW is not different between pre and post LAD ligation(78.2+/-23.4 vs 81.2+/-24.5 ; p=0.3778). CONCLUSION: These findings indicate that the myocardial blood flow and its decrease due to LAD ligation can be evaluated accurately by second harmonic imaging myocardial contrast 2D echocardiography.
Coronary Vessels* ; Echocardiography* ; Ligation* ; Microbubbles ; Myocardial Ischemia ; Noise ; Reperfusion ; Swine ; Thorax ; Ultrasonography