Reverse Redistribution Pattern Research Articles

The Correlation of Reverse Redistribution Pattern with Coronary Angiography: A Conundrum Revisited

The Correlation of Reverse Redistribution Pattern with Coronary Angiography: A Conundrum Revisited

Effect of the reverse redistribution pattern on the left ventricular ejection fraction in the Tc-99m MIBI SPECT myocardial perfusion scintigraphy

Objective: The causes and prognostic significance of the reverse redistribution pattern (RRP) is not clear yet. In this study, we aimed to evaluate the RRP effect on the left ventricular ejection fraction (EF).Methods: Imaging of the patients whose technetium-99m sestamibi myocardial perfusion scintigraphy was carried out and reported as normal were retrospectively examined. One-day protocol and/or pharmacologic stress testing applied patients were excluded. 21 patients with RRP met the inclusion criteria. All of these patients were included in the study as RRP group. Randomly selected 21 patients with non-RRP were included in the study as control group. Transient ischemic dilation (TID) scores and EF values were automatically calculated with the Quantitative Gated SPECT (QGS) program. Results: While a statistically significant difference was not found between the RRP and control groups in terms of age, sex, hypertension, family history, hyperlipidemia, and diabetes (p>0.05), there was a statistically significant difference in terms of smoking (p=0.019). TID scores in the RRP group were significantly lower compared to the control group (p<0.001). In addition, a statistically significant decrease was determined in the EF values in the rest images compared to the stress images in the RRP group (p=0.002). Furthermore, this decrease was significantly higher than in the control group (p= 0.034). Conclusion: The results related to the TID scores and EF values are suggesting the existence of an ischemic cause in the background of the RRP. Additionally, the relationship found between smoking and RRP may be associated with the tachycardia and / or coronary spasm-inducing effect of smoking. J Clin Exp Invest 2015; 6 (3): 286-290

Political Parties and Higher Education Spending: Who Favours Redistribution?

A nation's endowment with human capital is an important source of economic prosperity, yet education systems as well as the amount of public spending differ both between and within industrialised countries. Traditional approaches in comparative political economy explain education spending from a perspective in which leftist parties favour human capital formation. In contrast, recent approaches claim that – with regard to public financing of higher education in stratified education systems – the basic assumptions of partisan theory rather lead to the opposite hypothesis. In such systems, a pattern of reverse redistribution emerges, under which electoral incentives let right-wing parties favour increases in higher education budgets. This article tests both claims within the decentralised German education system. Its encompassing empirical strategy provides clear support for the latter hypothesis in the 16 German states between 1992 and 2003. The results imply that the partisan composition of government and preferences for redistribution continue to matter.

Significance of abnormal myocardial perfusion scintigraphy in young adult patients with SLE

Detection of subclinical coronary artery disease (CAD) is a potential challenge in patients with systemic lupus erythematosus (SLE) and it is suggested that myocardial perfusion single photon emission computerized tomography (SPECT) is more sensitive than exercise test in this setting. However, the significance of perfusion abnormalities in SLE patients is not well known. In this study, we evaluated the prognostic significance of myocardial perfusion defects in patients with SLE. Patients with proven diagnosis of SLE admitted to the hospital due to noncardiac problems with no history of CAD were studied. All patients underwent (99m)Tc-MIBI myocardial perfusion scan using dipyridamole as pharmacological stress. All patients were followed up by reviewing patients file in lupus clinic and any minor or major cardiac events were recorded. Eighteen female and two male patients with mean age of 28.2 +/- 12.05 years were included. Six patients had mild reversible perfusion defects with mean summed difference score of 2.5 +/- 1.0. Pattern of reverse redistribution (reverse fill-in) was noted in three patients. Eleven patients had normal myocardial perfusion. Hypokinesia was noted in three patients on gated images. One patient with abnormal perfusion died 21 days after imaging due to non-cardiac cause. Nineteen patients were followed for a mean time of 39.2 +/- 16.0 months. No major or minor cardiac events were noted during follow-up. Three patients (one with abnormal perfusion) had at least one readmission during follow-up period. Our study showed that myocardial perfusion abnormalities are fairly frequent in SLE patients but the defects are generally mild and do not advocate an adverse prognosis.

Reverse Redistribution Phenomenon In Patients With Normal Coronary Epicardial Arteries And Its Relationship To Systolic Left Ventricular Dysfunction

Background: Among the different imaging patterns found in myocardial perfusion imaging, the true significance of the reverse redistribution remains a controversial subject. Objective: The objective of this study was to evaluate the prevalence of reverse redistribution and its relation to left ventricular systolic function among a cohort of patients who underwent coronary angiography and scintigraphic study Methods: We retrospectively analyzed the data of patients with normal coronary arteries on angiography and who had a scintigraphic study. Results: There were 42 patients who had normal coronaries on coronary angiography and had a scintigraphic study; 16 (38.1%) had reverse redistribution pattern. Patients with reverse redistribution pattern showed higher prevalence of myocardial infarction (31 vs. 7.7%) and diabetes mellitus type 2 (50 vs. 23%) than those who did not show the pattern. Subjects with severe reverse redistribution had lower left ventricular ejection fractions (43.3 ± 1.5% vs. 61.5 ± 15.4%) than subjects without it. Conclusion: Among patients undergoing coronary angiography and Tc99 Sestamibi myocardial perfusion scintigraphy, severe reverse redistribution was associated with lower left ventricular ejection fraction

A Reverse Perfusion Pattern During Technetium-99m Stress Myocardial Perfusion Imaging Does Not Predict Flow Limiting Coronary Artery Disease

A reverse redistribution pattern during myocardial perfusion imaging is most widely described using thallium (Tl-201), when stress images exhibit greater perfusion than rest. Technetium (Tc-99 m) radiopharmaceuticals may also yield a reverse perfusion (RP) pattern, but its significance is uncertain. This study tested the hypothesis that RP correlates with the presence and location of flow limiting coronary stenosis(es). We reviewed 842 consecutive Tc-99 m tetrofosmin SPECT stress studies performed at a cardiothoracic centre over a 15 month period. 69 (8.2%) demonstrated RP. Thirty-three patients (age 32-79 mean 56, 17 female) had undergone cardiac catheterisation within 12 months of the scan. Correlation was sought between the presence and location of angiographic stenoses and RP pattern. 10/33 (30.3%) had significant (>60%) coronary stenosis(es); 5 single-vessel, 2 two-vessel and 3 three-vessel disease (3VD). Stenosis location correlated poorly with the RP territory (LAD/Anterior 5/17, RCA/Inferior 1/10, Cx/lateral 0/4 (p = 0.57)). Of the 6 patients with a lesion in the RP territory, 3 had 3VD; 2 of these had a simultaneous reversible defect. All 5 patients with previous myocardial infarction had a simultaneous fixed defect. However only 3/12 with co-existent reversible defects had significant disease. The reverse perfusion pattern is a poor predictor of flow limiting coronary disease, and does not correlate with stenosis location in those with significant lesions. Such patients should not undergo invasive investigation purely on the basis of this result.

The clinical significance of reverse redistribution in Tl201 cardiac SPET.

In an attempt to evaluate the clinical significance of reverse redistribution in Tl201 cardiac SPET, Tl201 SPET examinations included in the data base of our department have been retrospectively reviewed. Six hundred ninety eight patients demonstrated the pattern of reverse redistribution. For 237 of these patients' cardiac catheterization data were also available. One hundred and six patients of these had a history of myocardial infarction while the rest of them were referred for angina symptoms. Catheterization showed that the infarction area was perfused by a stenosed but patent vessel in 79 of the 106 patients with a history of myocardial infarction (74.5%). Collateral circulation was evident in 21 of these 106 patients (19.8%). Only six patients (5.6%) showed a totally occluded vessel with no obvious evidence of collateral circulation. Of the 131 patients, with no myocardial infarction history, 14 (10.7%) had normal coronary vessels. The rest of the patients (89.3%) demonstrated stenotic vessels perfusing the same area where reverse redistribution was observed. Sixty-three of these patients have been reexamined after 9-36 months. On 15 of these patients (23.8%) the second scintigram showed ischemia in the same segments where reverse redistribution was initially detected. Another 17 of the above patients had a former scintigraphic examination that showed ischemia on the segments that currently demonstrated reverse redistribution. The results of the present retrospective study indicate that, in patients with known coronary disease, the pattern of reverse redistribution frequently indicates the ischemic area.

Reverse redistribution: Revisited with myocardial contrast echocardiography

The aim of this study is to better understand the pattern and nature of reverse redistribution (RR) in myocardial perfusion imaging. In 20 consecutive acute myocardial infarction (MI) patients, frequency of RR was correlated with that of subendocardial MI that was detected by myocardial contrast echocardiography (MCE). RR was judged to be present when there was more than one grade of worsening in perfusion on 24 hr delayed images compared with the initial rest images. MCE evaluated no opacification in the subendocardial myocardium to suggest subendocardial MI. Kendall's nonparametric correlation coefficiency was calculated. Concordant cases were 15 of 20 (75%) and correlation was statistically significant (p = 0.0285). Our results suggested that RR was correlated with MCE-detected nontransmural MI.

Technetium-99m sestamibi single-photon emission tomography detects subclinical myocardial perfusion abnormalities in patients with systemic lupus erythematosus.

In patients with systemic lupus erythematosus, involvement of the cardiovascular system is the third leading cause of death. However, although autopsy studies have demonstrated a high incidence of abnormalities in both the myocardium and coronary vessels, clinical manifestations have been reported in only a small percentage of cases. The aim of this study was to evaluate myocardial perfusion in asymptomatic lupus patients using technetium-99m sestamibi single-photon emission tomography (SPET). Twenty-eight patients without overt cardiac involvement and risk factors were studied with 99mTc-sestamibi SPET at rest and after dipyridamole infusion. Perfusion abnormalities were detected in 18 cases: six had persistent defects, three had reversible defects, seven had both persistent and reversible defects, and two showed rest defects which normalized on dipyridamole images ("reverse redistribution pattern"). Coronary angiography was performed in eight patients with positive 99mTc-sestamibi SPET, and showed normal epicardial vessels in all the cases. These results indicate that 99mTc-sestamibi SPET reveals a high prevalence (18 out of 28 patients in this study, i.e. 64%) of myocardial perfusion abnormalities in asymptomatic lupus patients, probably due to the primary immunological damage of this autoimmune disease. In conclusion, rest/dipyridamole 99mTc-sestamibi SPET can be a useful non-invasive method to identify subclinical myocardial involvement in systemic lupus erythematosus, and patients potentially at risk of later cardiac events.

Prediction of post-revascularization functional recovery of asynergic myocardium using quantitative thallium-201 rest-redistribution tomography: has the reverse redistribution pattern an independent significance?

The significance of reverse redistribution on rest-redistribution thallium-201 myocardial scintigraphy is unclear. Previous studies suggested that reverse redistribution segments with normal resting activity include viable myocardium, whilst resting defects with further worsening correspond to scar. We evaluated whether reverse redistribution has an independent significance for the prediction of post-revascularization recovery, particularly as compared with the quantification of redistribution activity. We studied 26 coronary artery disease patients with left ventricular dysfunction, who underwent 201Tl rest-redistribution single-photon emission tomography (SPET) and echocardiography before revascularization. Viability was defined by the detection of wall motion improvement on follow-up echocardiography. 201Tl activity was considered normal if >/=80%, moderately reduced if <80% but >/=50%, and severely decreased if <50%. Reverse redistribution was defined as a defect in redistribution images with >/=10% decrease in relative 201Tl activity compared with the resting value. Reverse redistribution was detected in 33 segments (10%). Baseline dysfunction was equally observed in the reverse redistribution and in the non-reverse redistribution segments (64% vs 56%, P=0.40) and the rate of asynergic segments with post-revascularization recovery was not different between the two groups (33% vs 54%, P=0.11). The rate of functional recovery in redistribution defects without reverse redistribution was 53% in moderate and 30% in severe defects; the corresponding values for the reverse redistribution segments were 50% and 27% (all non-significant versus non-reverse redistribution segments). For the prediction of post-revascularization recovery in asynergic segments, the detection of reverse redistribution on rest-redistribution 201Tl SPET does not add any information to the quantitative analysis of redistribution activity.

Prediction of functional recovery in acute myocardial infarction: Comparison between sestamibi reverse redistribution and sestamibi/BMIPP mismatch

Background. It has been known that Tc 99m sestamibi/iodine 123 betamethyliodophenylpentadecanoic ( 123I-BMIPP) (sestamibi/BMIPP) mismatch is an indicator of viable myocardium in acute myocardial infarction (AMI). We have reported that reverse redistribution of sestamibi in AMI indicates the patency of infarct-related artery and a preserved left ventricular function in the chronic stage. In this study we investigated the relationship between reverse redistribution of sestamibi and sestamibi/BMIPP mismatch in patients with AMI. Methods. Twenty-three patients with AMI who received direct percutaneous transluminal coronary angioplasty underwent both BMIPP and sestamibi SPECT within 2 weeks after onset. Sestamibi images were obtained 1 hour (early) and 3 hours (delayed) after injection of sestamibi. BMIPP imaging was carried out 30 minutes after injection. The left ventricle was divided into 17 segments, and regional myocardial uptakes of the tracers in each segment were scored from 0 (normal) to 3 (no activity). A reverse redistribution pattern was defined as an increase of />1 in the regional score at the delayed images. More reduced BMIPP uptake than sestamibi uptake in each segment was determined as sestamibi/BMIPP mismatch. Contrast left ventriculography was performed soon after revascularization and repeated 1 month later. Results. Of 15 patients with sestamibi reverse redistribution, sestamibi/BMIPP mismatch was observed in 14 patients (93%), whereas mismatch was seen in only one of seven patients (14%) without reverse redistribution ( p < 0.01). In patients with sestamibi reverse redistribution, regional scores of BMIPP agreed with those of early and delayed images of sestamibi in 51 segments (46%) and in 92 segments (83%), respectively. In the chronic stage, both regional wall motion and left ventricular ejection fraction improved in patients with sestamibi reverse redistribution (wall motion score: 6.7 ± 2.4 vs 2.7 ± 2.1, p < 0.01; ejection fraction: 56% ± 7% vs 64% ± 8%, p < 0.01), but not in those without reverse redistribution. Conclusion. Both reverse redistribution of sestamibi and sestamibi/BMIPP mismatch reflect the recovery of left ventricular function and thus imply myocardial viability in AMI. Because the presence of reverse redistribution of sestamibi agreed with that of sestamibi/BMIPP mismatch, additional BMIPP images can be replaced by the delayed images after a single injection of sestamibi.

'Reverse redistribution pattern' during myocardial perfusion imaging with 99Tcm-MIBI.

We retrospectively studied 540 consecutive patients with coronary artery disease (CAD) undergoing 99Tcm-methoxy-isobutyl-isonitrile (99Tcm-MIBI) myocardial single photon emission tomography (SPET) to determine the incidence of the 'reverse redistribution pattern' (RRP). RRP is similar to reverse redistribution (RR) in 201Tl myocardial SPET and is defined as the presence of a perfusion defect on the resting cardiac image, rather than on the exercise image. Our results confirmed 30 (5.6%) patients to have RRP, all of whom underwent diagnostic coronary angiography. None of the 30 patients showed RRP in the territory of the left circumflex coronary artery. RRP occurred in the territory of the left anterior descending coronary artery (LAD) in 16 patients, 12 of whom had a normal LAD. Fourteen patients presented with RRP in the territory of the right coronary artery, all of whom had normal coronary arteries. RRP in 99Tcm-MIBI myocardial SPET is less common than RR in 201Tl myocardial SPET and is frequently associated with normal coronary arteries. RRP with 99Tc(m)-MIBI seems to be of little value in the diagnosis of CAD.

Critically ischemic myocardium in clinically stable patients following thrombolytic therapy for acute myocardial infarction: Potential implications for early coronary angioplasty in selected patients

The utility of post-thombolysis, rest-redistribution thallium (TI)-201 scintigraphy was studied in 32 patients with a first myocardial infarction who were clinically stable following reperfusion. Day 1 scintigraphy obtained 5 ± 4 hours (range 1 to 16) after thrombolysis revealed an average perfusion defect of 6.5 ± 2.6 segments (range 1 to 11). There was a total of 208 abnormal segments, 137 of which were nonreversible at 4 hours, 50 of which were fully or partially reversible, and 21 of which had a reverse redistribution pattern. Repeat TI-201 scintigraphy on day 10 revealed significantly smaller perfusion defects of 4.9 ± 2.4 segments (range 0 to 9) with improvement predominantly of the day 1 reversible segments, and the improvement in segmental perfusion correlated with better regional left ventricular function. Twenty-nine (58%) of the 50 reversible segments normalized by day 10, and 11 (22%) improved, whereas only 16 (12%) of 137 nonreversible segments had normalized by day 10, only 9 had (6%) improved and 112 (82%) were unchanged ( p < 0.001 reversible versus nonreversible). There was no significant change in segments with a pattern of reverse redistribution. The improvement of reversible segments was greater in the 16 patients who underwent coronary angioplasty (PTCA) during the interval between the two scintigrams than in the 16 who did not. All 24 reversible segments in the PTCA group improved or normalized by day 10 compared with 16 (62%) of 26 reversible segments in the No PTCA group ( p < 0.001). Furthermore, 8 of the 10 reversible segments in the No PTCA group that did not improve actually deteriorated and became nonreversible by day 10. The minor improvement of nonreversible segments was not related to PTCA. Consistent with the findings in individual segments, the 19 patients with a reversible component on the day 1 TI-201 scintigram had significantly greater improvement in perfusion defect by day 10 than the 13 patients without a reversible component (37 ± 33% versus 7 ± 22% decrease in perfusion defect severity, p < 0.05), and this improvement was greatest in the 10 patients with a reversible component who underwent PTCA. In contrast, PTCA had no impact on the perfusion defect in the 13 patients without a reversible component. Our data suggest that following thrombolytic therapy for acute myocardial infarction, viable myocardium in the reperfused zone may remain ischemic, as manifested by a reversible pattern of TI-201 redistribution at rest, and thus may be in jeopardy of gradual progression to necrosis. Since PTCA appeared to prevent necrosis in these “critically ischemic” or “moribund” myocardial segments, out findings may have implications for the early recognition of a subgroup of patients who may benefit from post-thrombolysis PTCA of the residual stenosis of the artery of infarction.

Reverse redistribution of thallium-201: A sign of nontransmural myocardial infarction with patency of the infarct-related coronary artery

The pattern of reverse redistribution on the day 10 poststreptokinase resting thallium-201 myocardial scintigrams is a common finding in patients who have undergone streptokinase therapy in evolving myocardial infarction. To investigate this phenomenon, 67 patients who underwent streptokinase therapy were studied pre- and 10 days poststreptokinase therapy resting thallium-201 studies, poststreptokinase therapy resting radionuclide ventriculography and coronary arteriography (60 of the 67 patients). Of the 67 patients, 50 (75%) showed the reverse redistribution pattern on the day 10 thallium-201 study (Group I), 9 (13%) had a nonreversible defect (Group II) and the remaining 8 (12%) had a normal study or showed a reversible defect (Group III). The reverse redistribution pattern was associated with patency of the infarct-related artery (100%), quantitative improvement in resting thallium-201 defect size from day 1 to day 10 study (94%) and normal or near normal wall motion on day 10 radionuclide ventriculography (80% of segments with marked and 54% of those with mild reverse redistribution). In contrast, nonreversible defects were associated with significantly less frequent patency of the infarct-related artery (67%, p = 0.01), improvement in defect size (11%, p less than 0.001) and normal or near normal wall motion (21%, p less than 0.05). Group III patients were similar to Group I with respect to these variables. The quantitated thallium-201 percent washout was higher in the regions with the reverse redistribution pattern (49 +/- 15%) compared with the contralateral normal zone (24 +/- 15%, p less than 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)