Holistic polar map for integrated evaluation of cardiac imaging results.

Polar map display (PM) is a comprehensive interpretation of the left ventricle. This is a non-rigid registration of the left ventricle originally for the visual and quantitative analysis of tomographic myocardial perfusion scintigrams. In this scheme the maximal-count circumferential profiles of well-defined short- and long-axis planes are plotted to a map showing the distribution of the perfusion tracer onto a two-dimensional polar representation. The usual coronary artery distribution is often indicated on the PMs of SPECT studies by referring to the regions of the three main coronary branches, nevertheless, the individual variations may differ extensively. We set out to develop an Access (Microsoft)-based computer program that permits an integrated evaluation of the imaging results (coronary angiography, echocardiography and SPECT) on patients with coronary artery disease. This semi-quantitative registration of the coronary tree to a PM focused on the relation between the supplying coronary branches and the myocardial regions of the 16-segment left ventricular evaluating model. All the recorded anatomical and functional data were related to these 16 left ventricular segments, which allowed the direct comparison and holistic synthesis of the results. Two projections were taken into consideration for generation of the coronary PM: from the right anterior oblique projections, the left anterior descendent (LAD)/right coronary artery (RCA) border was assessed through the comparison of the left and right coronary angiograms. The terminations of the visually detected end-arteries showed the separation of the myocardial beds supplied by the two branches. The border of the myocardial beds on the polar map was determined on the "vertical axis" of the local coordinate system. The RCA/ left circumflex (LCx) separation can be determined from the left anterior oblique view. In this projection, the left ventricular septal edge was delineated by the LAD, while the LCx indicated the lateral epicardial surface. The individual coronary artery circulation was typified from among 12 variations in the Holistic Coronary Care program. With this determination of the individual coronary circulation, the lesion-associated segments are generated automatically by the software. The lesion-associated regions are defined as the myocardial bed of a diseased artery distal to the lesion. The PMs generated from the coronary angiographic results were compared with those of 99Tc-labelled MIBI single photon emission computed tomography (SPECT) in order to test the accuracy of the localizing method. The overlap between the segments associated with the coronary lesion and the stress perfusion defects (<80% relative MIBI activity during stress tests) was analyzed in 10 patients with (sub)total coronary occlusion after myocardial infarction. The distributions of the segments with stress perfusion defects on MIBI SPECT gave positive and negative predictive values of coronary occlusion of 0.94 and 0.8, respectively. According to the 16-segment wall motion analysis by echocardiography, the positive and negative predictive values of coronary occlusion for wall motion abnormality were 0.82 and 0.76, respectively. While the distal part of the subtended region usually demonstrated a higher degree perfusion abnormality than the proximal part, the high positive predictive value proved that, during the stress condition, the perfusion defect could be detected in practically all the subtended regions. The low negative predictive value of the coronary lesion for the wall motion abnormality was associated with the remodeling of the entire left ventricle.     

Isotopic findings in anomalous origin of the left coronary artery from the pulmonary artery: report of an adult case

Anomalous origin of the left coronary artery from the main pulmonary trunk results in myocardial ischemia or infarction, and may be a cause of death in the first months of life. Some patients, however, develop satisfactory coronary collateral circulation and remain asymptomatic into adulthood. In these patients, myocardial perfusion and left ventricular function are not well understood. We report the case of a 17-yr-old female patient, suffering from anomalous origin of the left coronary artery from the main pulmonary trunk, who underwent reimplantation of the left coronary artery to the aorta. The preoperative permanent 201Tl defect of the left antero-lateral ventricular wall and the abnormal regional wall motion induced by stress exercise testing were fully reversed after the operation.     

Dipyridamole Tl-201 myocardial single photon emission computed tomography in the functional assessment of anomalous left coronary artery from the pulmonary artery

Anomalous origin of the left coronary artery from the pulmonary artery is a rare congenital heart disease. Without surgical correction, most patients with this anomaly die during infancy from myocardial infarction and heart failure, with a mortality rate reported to be greater than 90% by 1 year of age. Some patients with significant collateral circulation from the right coronary artery may remain asymptomatic and survive into adulthood, but they usually develop progressive left ventricular dysfunction. The detection of myocardial ischemia in these patients is important to identify viable myocardium at risk for irreversible damage. We present 1 such case in which dipyridamole Tl-201 SPECT myocardial perfusion imaging played an important role in the decision-making process and was shown to be useful for the evaluation of the surgical result.     

Specific perfusion pattern in stress 201Tl myocardial scintigraphy of left main coronary artery disease

The usefulness of stress 201Tl myocardial scintigraphy for identifying left main coronary artery disease was evaluated with data from 23 patients with 50% or more narrowing of the left main coronary artery and 56 patients with 75% or more narrowing of the major coronary arteries but without left main coronary artery involvement (no left main coronary artery disease). Quantitative evaluation of stress perfusion scintigrams in all five patients with narrowing of the left main coronary artery of 90% or more showed a characteristic perfusion pattern (left main pattern) of extensive homogeneous defect over the whole anterolateral segment and simultaneous defects in all radii of the high anteroseptal and high posterolateral segments. On the other hand, such a perfusion pattern was noted in only 1 of 18 patients with less than 90% stenosis of the left main coronary artery and in only 1 of 56 patients with no left main coronary artery disease.     

Evaluation of coronary hemodynamics and exercise 201Tl-myocardial scintigraphy in patients with vasospastic angina]

To clarify the coronary hemodynamics and myocardial perfusion in patients with vasospastic angina, we performed exercise-201Tl-myocardial scintigraphy (planar and SPECT) in 72 patients and left coronary digital subtraction angiography (DSA) in 37 patients without significant organic coronary artery stenosis. Coronary artery spasm was documented by coronary angiography in all patients. Fifty-four patients (75%) developed exercise-induced 201Tl-myocardial perfusion defect on SPECT. 201Tl pulmonary uptake (L/H) was significantly increased in patients with vasospastic angina. Especially, L/H was higher in patients with multiple small perfusion defect on 201Tl-SPECT, so that exercise-induced left ventricular dysfunction existed in patients with vasospastic angina and especially in cases with multiple small perfusion defect on 201Tl-SPECT. The left coronary circulation time (CCT) was prolonged in patients with vasospastic angina. The mechanism of prolonged CCT is still unknown, but we suspected that prolonged CCT was induced by increased peripheral coronary vascular resistance in patients with vasospastic angina. It was concluded that the peripheral coronary circulation was disturbed in patients with vasospastic angina, but its abnormal coronary circulation had no relation to location of spasm-induced vessels. We concluded that impaired coronary microcirculation was taken a part of pathophysiology in vasospastic angina.     

Specific perfusion pattern in stress 201Tl myocardial scintigraphy of left main coronary artery disease

The usefulness of stress ²⁰¹Tl myocardial scintigraphy for identifying left main coronary artery disease was evaluated with data from 23 patients with 50% or more narrowing of the left main coronary artery and 56 patients with 75% or more narrowing of the major coronary arteries but without left main coronary artery involvement (no left main coronary artery disease). Quantitiative evaluation of stress perfusion scintigrams in all five patients with narrowing of the left main coronary artery of 99% or more showed a characteristic perfusion pattern (left main pattern) of extensive homogeneous defect over the whole anterolateral segment and simultaneous defects in all radii of the high anteroseptal and high posterolateral segments. On the other hand, such a perfusion pattern was noted in only 1 of 18 patients with less than 90% stenosis of the left main coronary artery and in only 1 of 56 patients with no left main coronary artery disease     

Anomalous origin of left main coronary artery: the value of myocardial scintigraphic and spiral computed tomography scans

Anomalous origin of the left main coronary artery (LMCA) from the right sinus of the Valsalva or the proximal right coronary artery (RCA) is one of the most clinically important anomalies of coronary circulation. We report the case of a patient with chest pain and abnormal thallium myocardial perfusion scan in whom the anomaly was first detected on invasive coronary arteriography. The exact anatomic course of anomalous LMCA was confirmed using contrast enhanced computed tomography.     

Evaluation of hemodynamic significance of arteriovenous coronary fistulas: diagnostic integration of coronary angiography and stress/rest myocardial scintigraphy

PURPOSE: We report on the importance of the integration of data obtained from digital coronary angiography and stress/rest 99mTc sestamibi myocardial perfusion single photon emission tomography in evaluating the hemodynamic significance of coronary arteriovenous fistulae. MATERIAL AND METHODS: Coronary fistulae were detected with coronary angiography in 9 patients. All patients underwent clinical examination, transthoracic echocardiography, stress electrocardiogram and stress/rest 99mTc sestamibi myocardial perfusion single photon emission tomography. RESULTS: Stress/rest 99mTc sestamibi myocardial perfusion single photon emission tomography and stress electrocardiogram showed stress-induced myocardial ischemia in 2 patients. The first patient with familial predisposition and risk factors for ischemic heart disease presented a mesocardic heart murmur on clinical examination. At stress ECG (125 Watt, 153 b/m' max frequency 93%, arterial pressure 230 mmHg, max frequency pressure product 35,200) ischemic alterations were recorded at the first minute of the second stage of the Bruce protocol. Coronary angiography detected a circumflex artery fistula in the coronary sinus. Stress/rest 99mTc sestamibi myocardial perfusion single photon emission tomography for the evaluation of stress/rest perfusion detected a reversible perfusion defect of the proximal portion of the posterolateral and lateral walls, thus confirming the hemodynamic importance of the flow through the fistula during stress cycloergometric testing. In the second patient familial predisposition to ischemic heart disease and previous inferior wall myocardial infarction and non-significant stress ECG, coronary angiography identified a subocclusive stenosis of the right coronary artery and an anomaly between the anterior interventricular artery and the left pulmonary artery. The presence of the contrast medium in the left pulmonary artery identified a flow from the left ventricle to the left pulmonary artery. Good angiographic results were obtained after percutaneous coronary angiography of the right coronary artery stenosis. Due to the onset of angina stress/rest 99mTc sestamibi myocardial perfusion single photon emission tomography was performed to evaluate stress/rest perfusion (75 Watt, 125 b/m', 88% max frequency, arterial pressure 200 mmHg, double max product 25,000 with ST depression of 1.5 mm in V1-V4) and identified an irreversible perfusion defect due to infarction and a reversible perfusion defect of the anterior wall and apex due to ischemia caused by the anomalous flow through the coronary fistula. The correspondence between the site of the coronary artery where the fistula originates, identified by coronary angiography, and the reversible perfusion defects, identified by stress/rest 99mTc sestamibi myocardial perfusion single photon emission tomography, indicates that the anomalous flow through the fistula may cause myocardial ischemia. The irreversible perfusion defects of the inferior wall are the result of right coronary artery subocclusive stenosis. CONCLUSIONS: Coronary fistulae cause myocardial ischemia only in a small number of patients. Data obtained from single photon emission tomography in evaluating stress/rest myocardial perfusion, correlated with data from coronary angiography, have shown that changes in patients with terminal coronary anomalies may be due to different coronary diseases: ischemia to anomalous flow through the fistula and myocardial infarction to subocclusive right coronary artery stenosis. Stress/rest 99mTc sestamibi single photon emission tomography for the evaluation of myocardial perfusion is a reliable means of assessing the functional importance of the terminal coronary anomalies detected by coronary angiography. Evaluation of the hemodynamic importance of the coronary fistulae is indispensable in programming corrective surgery.     

Cardiac MRI in ischemic heart disease with severe coronary artery stenosis

RATIONALE AND OBJECTIVES: The aim was to evaluate the left ventricular wall motion abnormalities, perfusion and late contrast enhancement patterns on magnetic resonance imaging (MRI) in patients with 70% or higher degree stenosis or occlusion of coronary arteries on coronary angiography. MATERIALS AND METHODS: Twenty-four patients (5 women, 19 men, age range 38-78, mean age 59.1) who had 70% or higher degree stenosis or occlusion of coronary arteries on coronary angiography who had been referred for cardiac MRI were included. On coronary angiography, 20 vessels were totally occluded [left anterior descending artery (LAD) 12; left circumflex coronary artery (LCx) 2; right coronary artery 6] and 20 vessels were severely stenotic (70-99%). In 5 patients' three vessels, in 6 patients' two vessels, and in 13 patients' a single vessel was involved. Wall motion, perfusion abnormalities, and late contrast enhancement consistent with nonviable myocardium were analyzed at apical, at midventricular, and basal levels on short-axis images of cardiac MRI in concordance with the segmental irrigation areas of the coronary arteries. RESULTS: Impaired perfusion was observed on the corresponding irrigation segments of 39 vessels of 40 coronary artery branches. Wall motion abnormalities were present on corresponding irrigation areas of 30 severely stenotic vessels. Combined evaluation of wall motion and perfusion, segments with the decreased left ventricular contraction, and perfusion matched with the corresponding irrigation areas of all of the 40 stenotic or occluded vessels. CONCLUSION: A correlation was found between the combined assessments of myocardial perfusion, wall motion, and viability on late contrast enhancement on cardiac MRI with the clinical and angiography findings. Thus this combined MRI protocol can be used for the evaluation of ischemic heart disease.     

Significance of 99mTc-labeled perfusion agents in the simultaneous assessment of myocardial perfusion and cardiac function

Simultaneous assessment of left ventricular myocardial perfusion and systolic function was accomplished by utilizing ECG-gated myocardial perfusion SPECT. This development in nuclear cardiology will be attributed to the recent advances in new 99mTc-labeled perfusion agents, multi-detector SPECT system and software for automatic edge-detection of the left ventricle. In this article, we described about the clinical utilities of this method in detecting "hibernating myocardium," severe coronary artery disease patients with exercise-induced LV dysfunction, in predicting functional recovery after reperfusion therapy for acute myocardial infarction patients and in diagnosing patients with right heart diseases.     

Abnormal 201Tl myocardial single photon emission computed tomography in energetic male patients with myocardial bridge

Myocardial bridge is a relatively benign condition where a major coronary artery is bridged by a band of muscle and narrows during systole, particularly during rapid heart rates. Its clinical presentation and electrocardiogram (ECG) changes overlap with that of coronary artery disease. 201Tl myocardial perfusion imaging is thus frequently prescribed for further evaluation. This retrospective study was carried out to determine the 201Tl image patterns in patients with myocardial bridge. A total of 17 male patients (aged from 30 to 63 years) who had a positive exercise ECG and angiographic evidence of myocardial bridge in the mid-third of the left anterior descending coronary artery were recruited. Most of them were robust and received routine physical check-ups. They had no known heart disease or medication that affected cardiac function. The patients' clinical presentations, echocardiograph and exercise ECG findings were analysed. 201Tl single photon emission computed tomography (SPECT) was performed by intravenous injection of 201Tl (111 MBq) immediately following stress (treadmill or dipyridamole induced) and 4 h after stress, using a fixed, right angle camera equipped with a low energy, general purpose collimator. The images were interpreted independently by two experienced nuclear medicine physicians. Nine of the 17 patients had anterior chest pain during exercise. All patients had an abnormal ECG during exercise, including ST-T wave depression in leads II, III and aVF, and v4-6. Except for eight patients revealing reversible perfusion defect (R), 16 of the 17 patients also exhibited a partial reversible perfusion defect (PR) or a significant reverse redistribution (RR) scan pattern in the anterior or inferior walls of the left ventricle. Myocardial bridge should be taken into consideration in energetic male patients who had abnormal exercise ECGs and the corresponding patterns of Tl SPECT abnormalities including R, PR and RR.     

成人冠状动脉起源异常的分类及其发生率

 目的 探讨成人冠状动脉起源异常(AOCA)类型及其发生率.方法 对2000年10月～2006年10月在我院行冠状动脉造影(1 520例)检出的26例存在AOCA患者资料,以及国内2006年10月以前发表的有关成人AOCA研究的8篇文献资料进行综合分析.结果 9组资料冠状动脉造影总例数48 158例,检出AOCA439例,检出率0.91%.右冠状动脉起源异常发生率0.55%(267例),明显高于左冠状动脉0.36%(174例),差异有统计学意义(P＜0.01).右冠状动脉起源于左冠窦为最常见类型,占41.5%(182例);其次为前降支和回旋支独立开口,占26.0%(114例).结论 我国成人AOCA多见于右冠状动脉,其中具有潜在临床危险的右冠状动脉起源于左冠窦为最常见类型,提示加强国人AOCA研究具有重要临床意义.     

Accuracy of 99mTc-tetrofosmin myocardial tomography in the evaluation of coronary artery disease

BACKGROUND: Technetium 99m-labeled myocardial agents have been proposed as an alternative to thallium 201. The aim of this study was to assess retrospectively the accuracy of exercise myocardial 99mTc-tetrofosmin scintigraphy with tomographic imaging (SPECT) in a large group population in the evaluation of coronary artery disease. Furthermore we evaluated the relation between the severity of scintigraphic impaired myocardial perfusion and the angiographic coronary artery stenoses in patients without myocardial infarction and with stenosis localized exclusively in the proximal segment of the 3 main coronary arteries. METHODS AND RESULTS: The study group consisted of 235 consecutive patients, 204 (87%) of whom were men, with a mean age of 57+/-10 years, and with suspected or known coronary artery disease, who underwent 99mTc-tetrofosmin SPECT and coronary angiography. Furthermore, 61 patients in a low-likelihood group for coronary artery disease were also studied. Significant disease was defined by > or = 50% luminal coronary artery stenosis in > or = 1 native coronary artery or major branch or in a saphenous vein graft or arterial mammary graft. The overall sensitivity was 95%, specificity was 76%, and predictive accuracy was 95%. The normalcy rate for the low-likelihood group was 93%. Sensitivity was 71% for the left anterior descending artery, 61% for the left circumflex artery, and 73% for the right coronary artery. Specificity was 94% for the left anterior descending artery, 96% for the left circumflex artery, and 91% for the right coronary artery. Predictive accuracy was 79% for the left anterior descending artery, 78% for the left circumflex artery, and 81 % for the right coronary artery. In patients without myocardial infarction linear regression analysis between scintigraphy and angiography showed a significant correlation in patients with severe proximal coronary artery stenosis (r = 0.53, P < .002), but not in those with moderate proximal stenosis (r = 0.31, P = NS). CONCLUSIONS: This study shows that 99mTc-tetrofosmin SPECT is accurate in the detection of coronary artery disease. The relation of the severity of scintigraphic impaired myocardial perfusion and angiographic coronary artery stenosis, however, may differ significantly in patients with proximal stenosis of different severity.     

Clinical validation of three-dimensional color-modulated displays of myocardial perfusion

Background

Two-dimensional polar maps have been validated previously with coronary arteriography for determining vascular involvement of defects from a patient’s myocardial perfusion distributions with and without quantification. The purpose of this study was to validate previously developed three-dimensional color-modulated surface displays representing myocardial perfusion.

Methods and Results

The validation consisted of comparing the agreement between the three-dimensional displays and two-dimensional polar maps in localizing perfusion defects to vascular territories in 30 patients (16 men/14 women) who underwent both a 1-day rest/stress exercise ^99mTc-labeled sestamibi study and coronary arteriography. Reading by two experts was used to identify the size and location of quantified defects and corresponding areas of reversibility seen in the polar maps and, on a separate day, in the three-dimensional displays. Agreement between the two-dimensional polar maps and the three-dimensional displays resulted in identical percentages for the localization of both defects and reversibilities: left anterior descending coronary artery, 87% (26/30); left circumflex coronary artery, 97% (29/30); right coronary artery, 97% (29/30); and coronary artery disease, 97% (29/30).

Conclusions

These results show that the color-modulated three-dimensional displays are at least as good as the CEqual polar maps in localizing a perfusion defect and its reversibility to angiographically defined vascular territories and thus could be used in the routine clinical evaluation of myocardial perfusion.     

Detection of superior vena cava stenosis with superior vena cava-superior left pulmonary artery shunt and pulmonary hypertension. Detection by nuclear medicine study

We present a 59 year old patient diagnosed of right superior lobe pulmonary carcinoma by CT scan. A ventilation/perfusion pulmonary scintigraphy quantified for study of pulmonary function after surgery was performed. The images show an abnormal pattern of the distribution of macroaggregate albumin (MAA) and extrapulmonary presence of tracer (right/left shunt). A first step dynamic study showed the existence of superior cava stenosis and passage of the tracer from the vena cava to the left pulmonary artery by collateral circulation (innominate vein) that not only explained the existence of the abnormal pattern of the MAA distribution but also what the cause of the right/left shunt was. After the resolution of the stenosis, the distribution pattern became normal and the extrapulmonary presence of MAA disappeared.     

Comparison between exercise myocardial perfusion and wall motion using 201Tl and 191Irm simultaneously

By exploiting the ultrashort half-life 191Irm as tracer for left ventricular first-pass angiocardiography and 201Tl as myocardial perfusion agent, direct comparison between myocardial perfusion and regional wall motion was obtained during the same exercise stress test in patients with non-significant coronary artery disease, in patients with recent myocardial infarction, and in patients six weeks after successful percutaneous transluminal coronary angioplasty (PTCA). A good agreement between regional myocardial perfusion and regional wall motion was observed in patients with non-significant coronary artery disease and in most patients with recent myocardial infarction. In contrast, discrepancies occurred at maximal exercise in patients studied six weeks after successful PTCA: only 38% of the patients with no evidence of restenosis and with a completely normal myocardial perfusion scintigraphy had a normal regional wall motion at maximal exercise stress. According to these results, a normal uptake of 201Tl six weeks after PTCA would mean that the circulation has been successfully reestablished but without predicting the functional capacities of the myocardial cells which remain altered at least six weeks after the revascularization procedure in about two-thirds of the patients. We conclude that 191Irm in combination with 201Tl offers the opportunity of performing myocardial perfusion and wall motion studies simultaneously both at rest and during exercise.     

Quantification of myocardial hypoperfusion with 99m Tc-sestamibi in patients undergoing prolonged coronary artery balloon occlusion

Percutaneous transluminal coronary angioplasty provides an excellent opportunity to investigate the location and quantity of hypoperfusion during sudden complete occlusion of one of the major coronary arteries. Thirty-five patients referred for elective percutaneous transluminal coronary angioplasty were injected intravenously with 99mTc-sestamibi during balloon inflation. To visualize and quantify the hypoperfused region, a map of perfusion was constructed from that occlusion study and from the control study performed on the following day. Patients were divided into groups according to proximal or distal occlusion within each of the three coronary arteries. The region of myocardium supplied by each coronary artery varied in location and extended outside the typical borders for all arteries, but most prominently for the left circumflex coronary artery. The quantities of hypoperfusion varied within each artery group, but the average hypoperfusion was greater for the left anterior descending coronary artery than for either the right coronary artery or the left circumflex coronary artery. It is concluded that the quantities of hypoperfusion were highly variable within each artery group. Occlusion of the left anterior descending coronary artery was associated with the largest ischaemic region. The area of hypoperfusion extended outside the typical borders, most prominently for the left circumflex coronary artery.     

Improved visualization of coronary arteries using a new three-dimensional submillimeter MR coronary angiography sequence with balanced gradients

OBJECTIVE: The goal of our study was to evaluate a new three-dimensional real-time navigator MR coronary angiography sequence to noninvasively visualize the coronary arteries. SUBJECTS AND METHODS: Fifteen healthy volunteers underwent MR coronary angiography with a new balanced turbo field-echo sequence in comparison with the standard turbo field-echo sequence. Signal-to-noise, blood-to-myocardium, blood-to-fat, and blood-to-pericardial fluid contrast ratios of the left and right coronary artery systems were measured. Image quality was graded, the length and diameter of the coronary arteries were measured, and the number of visible side branches was assessed. RESULTS: The balanced turbo field-echo images yielded a higher blood-to-myocardium and blood-to-pericardial fluid contrast ratio, a similar blood-to-fat contrast ratio, and a lower signal-to-noise ratio than the turbo field-echo images. On a 5-point grading scale (1, nondiagnostic or unreadable; 2, poor; 3, moderate; 4, good; 5, excellent), image quality was rated significantly better for the balanced turbo field-echo sequence than for the turbo field-echo sequence (left coronary artery, 4.0 +/- 0.6 vs 3.6 +/- 0.5 [p = 0.015]; right coronary artery, 4.4 +/- 0.4 vs 3.6 +/- 0.4 [p < 0.0001], respectively), resulting in a significantly longer segment of the three major coronary arteries visualized (left anterior descending coronary artery, 92 +/- 21 mm vs 79 +/- 24 mm; left circumflex coronary artery, 70 +/- 7 mm vs 60 +/- 18 mm; right coronary artery, 112 +/- 28 mm vs 95 +/- 27 mm) and a significantly higher number of side branches visualized (left anterior descending coronary artery, 2.9 +/- 1.3 vs 1.5 +/- 1.3; left circumflex coronary artery, 2.1 +/- 1.7 vs 1.0 +/- 1.2; right coronary artery, 3.7 +/- 1.7 vs 2.6 +/- 1.5). Mean imaging time per coronary artery was significantly shorter for the balanced turbo field-echo sequence (5.7 +/- 1.0 min) than for the turbo field-echo sequence (8.4 +/- 1.4 min) (p < 0.0001). CONCLUSION: Compared with standard turbo field-echo MR coronary angiography, optimized balanced turbo field-echo MR coronary angiography improves the visualization of the coronary arteries and their side branches within a significantly shorter imaging time.     

Three-dimensional fusion of coronary arteries with myocardial perfusion distributions: clinical validation.

Clinical decisions regarding diagnosis and effective treatment of coronary artery disease frequently require integration of information from various imaging modalities, which are acquired, processed, and read at different physical locations and times. We have developed methods to integrate the information in 2 cardiac imaging studies, perfusion SPECT and coronary angiography. Three-dimensional (3D) models of the coronary artery tree created from biplane angiograms were automatically aligned with 3D models of the left ventricular epicardial surface created from perfusion SPECT. Myocardial mass at risk was used as a unique measure to validate the accuracy of the unification. METHODS: Thirty patients were injected with the perfusion agent (99m)Tc-tetrosfosmin during balloon occlusion while undergoing percutaneous transluminal coronary angioplasty for single-vessel coronary artery disease. Thus, a single, severe perfusion defect was induced by a single coronary artery occlusion of known severity and placement. The accuracy of the unification was measured by computing the overlap between physiologic area at risk, determined using SPECT perfusion quantification techniques only, and anatomic area at risk, determined using coronary artery anatomy aligned with the epicardial surface of the left ventricle. RESULTS: The unification resulted in an 80% overlap of areas at risk, and an overlap of 84% of normal areas, for all coronary artery distributions. The mass at risk measured based on the unified anatomic information correlated with the physiologically based mass at risk as y = 0.92x + 10.3 g; r = 0.76, SEE = 10.4 g. CONCLUSION: A unification algorithm for automatically registering 3D models of the epicardial surface from perfusion SPECT and 3D coronary artery trees from coronary angiography has been presented and validated in 30 patient studies.     

冠心病患者冠状动脉侧支循环形成的形态学特点分析

目的:分析国人冠状动脉侧支循环的形态学特点。方法:将265例冠心病病人的冠状动脉造影结果进行分析,按Levin的方法进行分类,并与之比较。结果:不同狭窄程度两组间侧支循环开放率差别有高度统计学意义(X2=14.43,P<0.001)。三支血管间侧支循环开放率差别均有统计学意义(X2=3.96,X2=4.28,P<0.05)。东、西方组冠状动脉各支病变的侧支分布的比较差别有高度统计学意义(右冠状动脉X2=9.68,P<0.01;左冠状动脉X2=41.73,P<0.001;左冠状动脉旋支X2=8.54,P<0.01。结论:冠状动脉侧支循环的形成与冠状动脉狭窄程度及病变血管有关。中国人的冠状动脉侧支循环具有独特性。