Transient Ischemic Dilation Research Articles

Transient ischaemic dilation and post-stress wall motion abnormality increase risk in patients with less than moderate ischaemia: analysis of the REFINE SPECT registry.

Ischaemia on single-photon emission computed tomography (SPECT) myocardial perfusion imaging (MPI) is strongly associated with cardiovascular risk. Transient ischaemic dilation (TID) and post-stress wall motion abnormalities (WMA) are non-perfusion markers of ischaemia with incremental prognostic utility. Using a large, multicentre SPECT MPI registry, we assessed the degree to which these features increased the risk of major adverse cardiovascular events (MACE) in patients with less than moderate ischaemia. Ischaemia was quantified with total perfusion deficit using semiautomated software and classified as: none (<1%), minimal (1 to <5%), mild (5 to <10%), moderate (10 to <15%), and severe (≥15%). Univariable and multivariable Cox proportional hazard analyses were used to assess associations between high-risk imaging features and MACE. We included 16578 patients, mean age 64.2 and median follow-up 4.7 years. During follow-up, 1842 patients experienced at least one event. Patients with mild ischaemia and TID were more likely to experience MACE compared with patients without TID [adjusted hazard ratio (HR) 1.42, P = 0.023], with outcomes not significantly different from patients with moderate ischaemia without other high-risk features (unadjusted HR 1.15, P = 0.556). There were similar findings in patients with post-stress WMA. However, in multivariable analysis of patients with mild ischaemia, TID (adjusted HR 1.50, P = 0.037), but not WMA, was independently associated with increased MACE. In patients with mild ischaemia, TID or post-stress WMA identify groups of patients with outcomes similar to patients with moderate ischaemia. Whether these combinations identify patients who may derive benefit from revascularization deserves further investigation.

Adenosine single-photon emission computed tomography-derived transient ischemic dilatation and ejection fraction reserve fail to predict multivessel coronary artery disease.

Next to myocardial perfusion, single-photon emission computed tomography (SPECT) also allows for the assessment of nonperfusion parameters such as transient ischemic dilatation (TID) and a reduction of ejection fraction (EF) with stress imaging. This study aimed to evaluate the diagnostic value of TID and EF reserve for the detection of significant multivessel coronary artery disease (CAD). A total of 206 patients with suspected stable CAD prospectively underwent gated stress-rest Tc-tetrofosmin SPECT and invasive coronary angiography with routine fractional flow reserve (FFR) measurements, irrespective of imaging results. Left ventricular volumes, TID, and EF reserve were assessed and compared with FFR-defined severity of CAD. According to FFR, 92 (45%) patients had significant CAD, whereas 25 (12%) showed 2-vessel disease (VD) and 22 (11%) showed 3-VD. With an increasing extent of CAD, TID values and EF reserve did not change significantly (P=0.07 and 0.42 for trend, respectively). Conversely, absolute left ventricular volumes and EF differed significantly among groups of CAD severity (P<0.01 for all trends). SPECT-derived TID and EF reserve did not differ between patients with high-risk CAD (3-VD) and low risk or no significant CAD. Therefore, the present results advocate exerting caution when using these ancillary findings in clinical practice.

Evaluation of Myocardial Perfusion Imaging SPECT Parameters and Pharmacologic Stress Test with Adenosine Versus Coronary Angiography Findings: Are They Diagnostically Concordant?

Objectives:In this study our first aim was to evaluate the diagnostic concordance of myocardial perfusion scintigraphy (MPS) by pharmacological stress test with adenosine (APST) with coronary angiography (CAG). The secondary aim of this study was to evaluate the correlation between CAG findings and automated analysis parameters such as left ventricular ejection fraction, summed stress score (SSS), summed rest score, summed difference score (SDS), stress MPS defect percentage ratio (extent) and transient ischemic dilation (TID) obtained by myocardial perfusion imaging single-photon emission computed tomography (SPECT).Methods:A total of 129 patients (62 male, 67 female, median age: 60.02) undergoing MPS due to suspicion of coronary ischemia who also underwent subsequent CAG in the last year were included in this study, their MPS data and CAG results were compared.Results:There was no statistically significant diagnostic concordance when visual evaluation of MPS, quantitative MPS parameters and exercise treadmill test (ETT) electrocardiography results were used alone. In fact, diagnostic concordance was higher when automated analysis parameters like TID, SSS and extent values were added to MPS SPECT visual analyses. There was diagnostic concordance in 57.9% of APST patients and 41.7% of ETT patients. There was diagnostic concordance in 75.8% of APST patients and 52.6% of ETT patients who were older than 65 years of age.Conclusion:In our study, we found that the use of APST during MPS increases diagnostic concordance with CAG. Therefore, we think that it would be appropriate to use APST in women and elderly patients with limited exercise habits. The CAG diagnostic mismatch is far above what it should be when MPS reporting is only done with visual data, and it is not supported by quantitative data such as TID, SSS, SDS and extent.

P298Relevance of transient ischemic dilatation in elderly patients with comorbidities undergoing stress myocardial perfusion SPECT imaging

P298Relevance of transient ischemic dilatation in elderly patients with comorbidities undergoing stress myocardial perfusion SPECT imaging

Multivessel Coronary Artery Disease Presented With Normal Myocardial Perfusion Scan: The Significance of a High Transient Ischemic Dilation

Multivessel Coronary Artery Disease Presented With Normal Myocardial Perfusion Scan: The Significance of a High Transient Ischemic Dilation

Referral to coronary angiography post myocardial perfusion imaging

The current guidelines for CAD suggest that patients with moderate to severe ischemia should be referred for angiography and possible revascularization, while patients with mild ischemia can be safely treated medically. These recommendations are currently being tested in the ISCHEMIA trial. It is unclear how often patients with moderate to severe ischemia are referred to coronary angiography. The aim of this study is to identify the rate and predictors of referral to coronary angiography post MPI. A retrospective cohort study included patients with suspected or known CAD who were referred to PET-CT imaging MPI due various clinical indications between May 2011 and March 2017. Ischemic burden was measured by the sum difference score. Moderate to severe ischemia was defined by summed stress score more than 7. A total of 5060 patients were included. Approximately, one third of patients had prior coronary disease. The prevalence and extent of ischemia was higher among patients with previous coronary disease. Chest pain or shortness of breath was the most common indication for referral to MPI. Patients who had severe ischemia, nearly 70% of them were referred to coronary angiography within 90 days and 76.6% were referred to coronary angiography within one year. However patients with moderate ischemia were much less often referred to coronary angiography and less than half of these patients were referred to coronary angiography within 90 days. The independent predictors of referral to coronary angiography within 90 days among all patients were age, CAD, transient ischemic dilation and presence and degree of ischemia. This study found that the increase in patient’s age, Summed Different Score, Transient Ischemic Dilation, ischemia group, and having CAD can predict an increased in the coronary angiography referral, and CVA is a protective factor for referral to coronary angiography.

Left ventricular functional parameters by gated SPECT myocardial perfusion imaging in a Latin American country

BackgroundThere is paucity of data on left ventricular (LV) functional parameters using gated SPECT myocardial perfusion imaging (MPI) from the Latin American region. This study provides detailed information in low-risk patients both at rest and during exercise. Methods and ResultsWe studied 90 patients (50 men) with a very low likelihood of coronary artery disease. Gated-SPECT MPI was performed with Tc-99m MIBI using a 2-day protocol, with 16 frames/R–R cycle. The LV ejection fraction and volumes were not different between the rest and post-stress images. LVEF was 68 ± 7% post-stress and 70 ± 7% at rest in women, and 62 ± 7% and 63 ± 7%, respectively, in men (P = .19, .26). LV volumes were larger in men than women (P < .01). There were no differences in most variables obtained at rest or post-stress. Transient ischemic dilatation was similar, with upper limits of 1.20 and 1.19 in women and men, respectively (P = NS). ConclusionsThese data could prove helpful for the interpretation of gated SPECT MPI data in Latin America using identical protocol as used in this study.

ASSESSMENT OF TRANSIENT ISCHEMIC DILATATION IN THE SETTING OF AN OTHERWISE NORMAL MYOCARDIAL PERFUSION SCAN WITH CORONARY ANGIOGRAPHY IN PATIENTS OF THE U.S. DEPARTMENT OF VETERANS AFFAIRS

Transient ischemic dilation (TID) on myocardial perfusion imaging (MPI) has been recognized as specific indicator for multi-vessel coronary artery disease, especially in the setting of concomitant perfusion defects. The clinical significance of TID in an otherwise normal MPI has been a subject of

Correlation between Transient Ischemic Left Ventricular Dilation and Severity of Coronary Artery Disease

Correlation between Transient Ischemic Left Ventricular Dilation and Severity of Coronary Artery Disease

Angiographic results of the patients with positive transient ischemic dilatation on their gated myocardial perfusion imaging scans

Angiographic results of the patients with positive transient ischemic dilatation on their gated myocardial perfusion imaging scans

Myocardial Perfusion Scans and Mortality in Asymptomatic Patients Awaiting Renal Transplantation

Cardiac risk assessment for asymptomatic patients awaiting renal transplantation is controversial. Patients awaiting renal transplantation in Southern Saskatchewan from 2005 to 2015 were retrospectively reviewed. Patients underwent cardiac risk stratification with stress myocardial perfusion scan. Baseline clinical characteristics, nuclear scan results, all-cause mortality, and cardiovascular events were analyzed. Abnormal scans were defined as studies with reversible defects, wall motion abnormalities, lung uptake, or transient ischemic dilation. Descriptive statistics and survival analysis were calculated. Charts from 285 consecutive patients with 608 nuclear scans were analyzed. Mean age was 55.2 ± 11.7 years and 34.7% were female. Forty-three (15.1%) patients were transplanted and 99 (40.9%) patients died while awaiting renal transplantation. One hundred fifty-three patients (63.2%) had at least one abnormal scan. The mean follow-up period was 5.47 ± 3.11 years. An abnormal scan was not associated with decreased survival and/or coronary events (hazard ratio: 0.94, P = .77; 95% confidence intervals: 0.62 to 1.43). Patients awaiting renal transplantation in Saskatchewan with abnormal myocardial perfusion scans were not at greater risk of death or coronary events.

Computer derived transient ischemic dilation ratio for identifying extensive coronary artery disease using a CZT camera and imaging in the upright position

BackgroundTransient ischemic dilation (TID) of the left ventricle (LV) has not been validated as a marker of extensive coronary artery disease (CAD) for studies using a cadmium-zinc-telluride (CZT) camera with upright imaging. MethodsTID ratios were obtained from upright stress and rest images on a CZT camera. Separate cut-off values were determined for exercise and for regadenoson stress. The cutoffs were then applied to 28 patients with extensive CAD and 101 patients without extensive CAD. ResultsWith treadmill exercise, an upright TID ratio ≥1.16 provided a positive predictive value of 50% and a negative predictive value of 85.4% for the identification of extensive CAD. In the regadenoson group, an upright TID ratio of 1.29 provided a positive predictive value of 20% and a negative predictive value of 75.9%. Although not an independent predictor of extensive CAD in all subjects, in subjects with a normal upright LVEF, it provided a predictive value by receiver operating characteristics comparable to the SSS. ConclusionsIncreased upright TID measurements on a CZT camera are associated with extensive CAD. The upright TID measurements can serve in an adjunctive role to SSS, and may be most effective in patients with a normal upright exercise LVEF.

Relation of Coronary Flow Reserve to Other Findings on Positron Emission Tomography Myocardial Perfusion Imaging and Left Heart Catheterization in Patients With End-stage Renal Disease Being Evaluated for Kidney Transplant

Cardiovascular disease is the leading cause of death in patients with end-stage renal disease (ESRD) and often goes undetected. Abnormal coronary flow reserve (CFR), which predicts increased risk of cardiac death, may be present in patients with ESRD without other evidence of coronary artery disease (CAD). We prospectively studied 131 patients who had rest and dipyridamole pharmacologic stress N13-ammonia positron emission tomography myocardial perfusion imaging (PET MPI) for kidney transplant evaluation. Thirty-four patients also had left heart catheterization. Abnormal PET MPI was defined as qualitative ischemia or infarct, stress electrocardiogram ischemia, or transient ischemic dilation. CFR was calculated as the ratio of stress to rest coronary blood flow. Global CFR < 2 was defined as abnormal. Of 131 patients who had PET MPI (66% male, 55.6 ± 12.1 years), 30% (39 of 131) had abnormal PET MPI and 59% (77 of 131) had abnormal CFR. In a subset of 34 patients who had left heart catheterization (66% male, 61.0 ± 12.1 years), 68% (23 of 34) had abnormal CFR on PET MPI, and 68% (23 of 34) had ≥70% obstruction on left heart catheterization. Abnormal CFR was not significantly associated with abnormal PET MPI (p = 0.13) or obstructive CAD on left heart catheterization (p = 0.26). In conclusion, in the first prospective study of PET MPI in patients with ESRD, abnormal CFR is highly prevalent and is independent of abnormal findings on PET MPI or obstructive CAD on left heart catheterization.

Transient Ischemic Dilation Ratio in Regadenoson, Single Isotope Gated Single-photon Emission Computed Tomography Myocardial Perfusion Imaging.

Single isotope 99mTc single-photon emission computed tomography-myocardial perfusion imaging (SPECT-MPI) is the most commonly used protocol for nuclear stress testing. Transient ischemic dilation of the left ventricle (TID) has been considered a specific marker of severe coronary artery disease (CAD). Recent publications have questioned the clinical utility of TID, specifically with regadenoson as a stressor and 4DM-SPECT software for TID analysis. These findings have not been demonstrated using other imaging packages. The goal of our study was to establish the TID threshold in the identification of Multi-vessel CAD using Quantitative Perfusion SPECT (QPS) software. Included in this study are 190 patients that had undergone regadenoson-stress, same day, single-isotope 99mTc MPI and had a coronary angiography within a designated 3-month period. QPS (Cedars-Sinai, LA, CA) automated image analysis software was used to calculate TID ratios which were compared across different CAD categories. Coronary angiograms were reviewed to identify both obstructive and nonobstructive CAD. The mean TID for patients with nonobstructive CAD (n = 91) was 1.02 ± 0.11, and the threshold for TID was 1.24. A receiver operating characteristic curve showed that TID had a poor discriminatory capacity to identify MVD (area under the curve 0.58) with a sensitivity of 3% and a specificity of 97%. In our study with regadenoson MPI in a predominantly African-American population, TID was found to be a poor predictor of MVD using QPS software. The reason is unclear but possibly related to the significant decline in the prevalence of severe CAD in the area where our study took place.

A Narrative-Review on Transient Ischemic Dilatation from Single Photon Emission Computed Tomography Myocardial Perfusion Imaging

Context: Transient ischemic dilatation (TID) of the left ventricle is a non-invasive marker of suspected or known Coronary Artery Disease (CAD), and is used for the prediction of prognosis. Because the value of TID has been emphasized by current publications in clinical nuclear cardiology field, the current review of the literature was conducted to present comprehensive overview on the findings in this field. Evidence Acquisition: Relevant literature was obtained by searching online databases, including MEDLINE/PubMed, Google Scholar, and Science Direct using the following keywords: transient ischemic dilation, Single Photon Emission Computed Tomography Myocardial Perfusion Imaging (SPECT MPI), procedural guidelines for myocardial perfusion imaging, and coronary artery disease. Articles were inspected to obtain good agreement criteria pertinent to the objective of the study. Overall, 21 relevant articles were selected to be included in the review. Results: Stress-induced subendocardial hypoperfusion, post-ischemic stunning, and impaired coronary flow reserve have been reported as common causes of TID. Transient Ischemic Dilatation can be easily measured by available automatic software on the market, including Emory Cardiac Toolbox, 4D-MSPECT, etc. A close correlation between TID and LV volume/function has been emphasized by previous researchers. Transient Ischemic Dilatation, in the setting of a cardiac SPECT MPI with abnormal findings, has been known to be a robust indicator of severe/extensive CAD and future cardiac events. However, only a limited number of publications are available for its probable use in the setting of normal MPI, especially based on patients at high-risk and those with TID. Conclusions: By using an upper limit value of TID that is derived according to the optimum imaging procedure of a particular laboratory, routine reporting of TID measurement as part of conventional SPECT MPI analysis may be useful.

Relationship between gated myocardial perfusion SPECT findings and hemodynamic, electrocardiographic, and heart rate changes after Dipyridamole infusion.

After dipyridamole infusion, electrocardiographic (ECG), blood pressure and heart rate (HR) changes were seen. We tried to investigate whether there is a relationship between hemodynamic, ECG and HR changes after dipyridamole infusion and gated myocardial perfusion SPECT findings. We studied 206 consecutive patients which underwent a 2-day protocol Dipyridamole Stress/Rest Tc99m-Sestamibi gated myocardial perfusion SPECT. Systolic blood pressure (SBP), diastolic blood pressure (DBP), HR and ECG were recorded. HR was mildly increased while SBP and DBP were mildly decreased after Dipyridamole infusion. There was only statistically significant difference between ECG changes as well as transient ischemic dilation (TID) ratio between normal scans and scans with ischemia (P = 0.02 and P = 0.01 respectively). There was correlation between these variables and summed stress score (SSS) and summed difference score (SDS). Patients with ischemia in their scans, 44.3% had ST depression after Dipyridamole infusion. Also ST depression most frequently was seen in patients with left anterior descending artery disease. From patients with abnormal scan + ST depression after Dipyridamole infusion (33 patient), 27 patient (81.81%) had ischemia. There was an association between TID ratio as well as ECG changes after Dipyridamole infusion and SSS, SDS and coronary artery territory abnormality. Difference between calculated left ventricular ejection fraction using stress and rest images had significant correlation with SSS and SDS. ST depression after Dipyridamole infusion and TID ratio had association with ischemia, SSS and SDS. So in equivocal Gated SPECT findings, they could be very useful for interpretation.

Diagnostic Invasive Coronary Angiography in Patients with Small Myocardial Perfusion Defects with Low Exercise Tolerance

Background: The diagnostic and prognostic value of stress myocardial perfusion scintigraphy is well established in literature. The sensitivity and specificity of the test depends on multiple factors. The workload achieved during treadmill exercise is one of the most important determinants. Hence, we thought to assess the coronary anatomy in a group of patients with low exercise tolerance that showed small perfusion defects on stress MPI studies. Material and methods: We prospectively enrolled 50 patients with mild perfusion defects and a poor exercise tolerance. An invasive coronary angiography was done according to the clinical decision of the treating physician. All patients were subjected to full history and clinical examination. Stress SPECT Tc99m Sestamibi scintigraphy was done on basis of a 2 day stress/rest imaging protocol (Exercise duration, age predicted maximal heart rate (APMHR %), ejection fraction (EF%), transient ischemic dilatation and duke treadmill score(DTS)) were recorded. A coronary stenosis ≥ 75% was considered significant. In the current study, APMHR 0.05 is considered significant. Results: Among the study cohort, a total of 6 patients (12%) had significant CAD. In presence of a small perfusion defect in the setting of low exercise tolerance, significant CAD was observed more frequently in patients with exercise duration ≤ 7 min, APMHR <85%, transient stress induced LV cavity dilatation and moderate/high DTS. The six patients with significant angiographic lesions demonstrated single vessel disease in the whole group. Distribution of the angiographic lesions was as follows: RCA (4 patients) 66.7%, the LAD (one patient) 16.65%, and the LCX (one patient) 16.65%. Conclusion: In the setting of low exercise tolerance, negative MPI/small sized perfusion defect may not exclude significant CAD. Several clinical, stress, and SPECT-MPI findings may help to predict high risk patients. Consideration of these factors may improve the overall assessment of the likelihood of significant CAD in patients undergoing stress SPECT- MPI.

Apparent left ventricular cavity dilatation during PET/CT in hypertrophic cardiomyopathy: Clinical predictors and potential mechanisms

BackgroundApparent left ventricular cavity dilatation (LVCD) in patients with hypertrophic cardiomyopathy (HCM) is an incompletely understood phenomenon. We aimed at investigating its clinical predictors and potential mechanisms. MethodsSixty one HCM patients underwent N-13-ammonia PET for visual evaluation of LVCD, transient ischemic dilatation (TID) index, myocardial blood flow (MBF), coronary flow reserve (CFR), and regional myocardial perfusion (rMP). TID index was also derived at 2–4 and 15–20 minutes. ResultsVisual LVCD and quantitative TID (>1.13 abnormal) agreement were excellent (k 0.91; P < .0001). LVCD-positive (n = 32) patients had greater LV thickness (2.26 ± 0.59 vs 1.92 ± 0.41 cm; P = .005), but lower stress MBF (1.66 ± 0.42 vs 2.07 ± 0.46 mL/minute/g; P < .0001), and CFR (1.90 ± 0.46 vs 2.46 ± 0.69; P < .0001) than LVCD-negative (n = 29) patients. Abnormal rMP was present in 31/32 LVCD-positive but only 12/29 (P < .0001) LVCD-negative. TID index was higher at 2–4 (1.30 ± 0.13) than at 15–20 minutes (1.27 ± 0.12; P = .001) in LVCD-positive, whereas it was the same (1.04 ± 0.07 vs 1.04 ± 0.07; P = .9) in LVCD-negative. In multivariate analysis, global peak MBF, abnormal rMP, and LV thickness were the best predictors of LVCD. ConclusionApparent LVCD is a common finding in HCM, intimately related to abnormal myocardial perfusion, globally impaired vasodilator flow reserve, and degree of hypertrophy. In addition to regional and/or diffuse subendocardial ischemia, some degree of true LV chamber dilatation may also contribute to the occurrence of apparent LVCD in HCM.

Regadenoson-induced coronary vasospasm resulting in severe reversible perfusion defects and transient ischemic dilation on SPECT stress myocardial perfusion imaging

A 58-year-old woman with hypertension and diabetes presented to the emergency department with exertional right-sided chest pain. Her cardiac biomarkers were negative and her electrocardiogram demonstrated no significant abnormalities. She subsequently underwent pharmacologic stress myocardial perfusion imaging using regadenoson. Her electrocardiogram demonstrated no significant ischemic changes and she only complained of dyspnea following regadenoson infusion. Perfusion images were acquired using the GE millennium MC scanner and processed using Xpress3 cardiac wide beam reconstruction software (UltraSPECT, Ltd.) at an xeleris functional imaging workstation. Review of the rotating raw data revealed breast attenuation artifact but no significant patient motion. Her perfusion imaging revealed a severe defect in the mid-to-distal inferolateral wall that was mostly reversible suggestive of significant ischemia. In addition, there was pronounced dilation of the left ventricle with stress (Figure 1). The patient underwent cardiac catheterization which demonstrated no obstructive coronary artery disease (Figures 2, 3). Upon further analysis of the patient’s history, she had apparently been diagnosed with Prinzmetal angina in the past and had undergone cardiac catheterization eight years prior for similar symptoms and this was normal as well. She was subsequently discharged on appropriate pharmacotherapy and was asymptomatic. Multiple reports have demonstrated coronary vasospasm after use of adenosine for stress testing. However, there is a limited data available in reference to regadenoson, which is a selective A2A adenosine receptor agonist. Recent emerging data demonstrate, however, that regadenoson may also lead to vasospasm as it has similar pharmacologic properties. Our case illustrates severely abnormal myocardial perfusion imaging with reversible regional ischemia and transient ischemic dilation with no obstructive coronary artery disease likely due to regadenoson-induced coronary vasospasm. Therefore, vasospastic heart disease is a potential confounding factor to consider in the interpretation of regadenoson stress MPI and may be clinically relevant in the management of patients with conflicting anatomic and perfusion findings.

Transient Ischemic Dilatation during Stress Echocardiography: An Additional Marker of Significant Myocardial Ischemia.

Left ventricular (LV) transient ischemic dilatation (TID) is not clear how it relates to inducible myocardial ischemia during stress echocardiography (SE). Eighty-eight SEs were examined from the site certification phase of the ISCHEMIA Trial. LV end-diastolic volume (EDV) and end-systolic volume (ESV) were measured at rest and peak stages and the percent change calculated. Moderate or greater ischemia was defined as ≥3 segments with stress-induced severe hypokinesis or akinesis. Optimum cut points in stress-induced percent EDV and ESV change that identified moderate or greater myocardial ischemia were analyzed. Analysis from percentage distribution identified a > 13% LV volume increase in EDV or a > 9% LV volume increase in ESV as the optimum cutoff points for moderate or greater ischemia. Using these definitions for TID, there were 27 (31%) with TIDESV and 12 (14%) with TIDEDV . By logistic regression analysis and receiver operating characteristic curves, the percent change in ESV had a stronger association with moderate or greater myocardial ischemia than that of EDV change. Compared to those without TIDESV , cases with TIDESV had larger extent of inducible wall-motion abnormalities, lower peak stress LVEF, and higher likelihood of moderate or grater ischemia. For moderate or greater myocardial ischemia detection, TIDESV had a sensitivity of 46%, specificity of 83%, positive predictive value of 70%, and negative predictive value of 64%. Transient ischemic dilatation by SE is a marker of extensive myocardial ischemia and can be used as an additional marker of higher risk.