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1.
BACKGROUND: Electrocardiographic (ECG) changes during adenosine myocardial perfusion imaging (MPI) correlate with severe coronary artery disease and the presence of collaterals. However, the significance of these changes during adenosine MPI in patients with left ventricular hypertrophy (LVH) on baseline electrocardiogram is less well understood. OBJECTIVE: To evaluate whether ECG changes on adenosine MPI predict ischaemia in patients with LVH. METHODS: We reviewed retrospectively 454 consecutive patients who had undergone adenosine MPI at our institution. The baseline electrocardiogram was reviewed to determine whether or not LVH was present. All patients were administered adenosine at 140 microg x kg x min for a total of 6 min and Tc-sestamibi was injected at 3 min into the protocol. None of the patients underwent any form of exercise during the stress test. RESULTS: Of the 146 patients with LVH, 10 had stress ECG changes suggestive of ischaemia and 40 had evidence of ischaemia on MPI. Similarly, of the 308 patients without LVH, 43 had stress ECG changes suggestive of ischaemia and 68 had ischaemia on MPI. The sensitivity and specificity of stress ECG changes in predicting ischaemia on perfusion in patients with LVH were 12.5% and 95.3%, respectively, with a positive predictive value of 50% and a negative predictive value of 74.3%. CONCLUSION: ECG changes suggestive of ischaemia in patients with LVH are very specific for ischaemia on MPI, and their significance is similar to that in patients without LVH.  相似文献   

2.

Background

Behçet’s disease (BD) is a systemic multi-system vasculitis that can have a wide range of effects on the cardiovascular system.

Objective

To determine the existence of myocardial perfusion defects caused by coronary microvascular dysfunction in BD and to evaluate coronary arterial distribution and left ventricular systolic function by gated single-photon emission computed tomography (SPECT).

Methods

The study population consisted of 23 (15 men and 8 women) patients with BD and 20 healthy controls (12 men and 8 women). Technetium-99m methoxyisobutylisonitrile (Tc-99m MIBI) gated SPECT studies were performed at stress and rest in a 2-day protocol. Stress and rest left ventricular ejection fraction (LVEF) were calculated. Using non-gated SPECT images myocardial perfusion scores [summed stress score (SSS), summed rest score (SRS), summed difference score (SDS), and fix defect score (FDS)] and perfusion defect extent as percentage (stress, rest ischemic, and fix %LV) were determined. Using gated SPECT images, wall motion score indices (stress wall motion score indices and rest wall motion score indices) were calculated. Coronary angiography (CAG) was applied to patients with abnormal myocardial perfusion scintigraphy (MPS).

Results

The mean ages of the BD and control groups were 39.3 ± 10.6 years and 36.2 ± 8.3 years, respectively. No statistically significant differences were observed between the two groups regarding clinical features and cardiologic findings. Abnormal MPS was found in 13 (56.5%) of the BD patients; 3 patients had non-transmural infarcts and 10 patients reversible perfusion defects. Reversible perfusion defects were also found in two controls (10.0%). When the two groups were compared regarding the gated SPECT findings, differences were determined in the following parameters; SSS, SRS, SDS, FDS, stress and rest LVEF, stress and rest %LV, and stress and rest WMSI. In the BD group, when gated SPECT results were compared between those with and without abnormal MPS, differences were determined in SSS, SRS, SDS, FDS, stress and rest %LV, and stress and rest WMSI. Epicardial coronary arteries were normal in CAG.

Conclusions

Myocardial perfusion and function are disturbed owing to influenced coronary microvascularity in BD, and CAG is frequently observed to be normal. Gated SPECT is a non-invasive reliable method that simultaneously evaluates the existence, extent and severity of myocardial ischemia or infarction and the wall movements in cardio-Behçet.
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3.

Purpose

A higher prevalence of cardiovascular risk factors (CRFs) in HIV-infected patients, together with chronic infection and treatments, has resulted in an increased risk of silent myocardial ischaemia (SMI). The objective of this study was to evaluate whether myocardial SPECT should be used for screening HIV-infected patients with no clinical symptoms of coronary artery disease.

Methods

The prevalence of SMI detected by myocardial SPECT was determined in 94 HIV-infected patients with a normal clinical cardiovascular examination in relation to anthropomorphic parameters, CRFs, inflammatory and HIV infection status, and treatment.

Results

Coronary artery disease was detected in nine patients (eight with ischaemia, one with myocardial infarction), corresponding to 9.6 % positivity. All but two of the scintigraphic diagnoses of ischaemia were confirmed by coronarography. Univariate analysis revealed that the overall number of CRFs and the combination of gender and age were associated with a diagnosis of SMI (p?<?0.05). According to multivariate analysis, the only independent parameter significantly associated with the scintigraphic diagnosis of SMI was the combination of gender and age (p?=?0.01). All the positive myocardial SPECT scans were in men older than 52 years with at least two other CRFs. In this subpopulation of 47 patients, the prevalence of SMI detected by myocardial SPECT reached 19.2 %.

Conclusion

In male HIV-infected patients older than 52 years and with at least two other CRFs, screening for SMI using myocardial SPECT was about four times more likely to be positive than in the general population. This may motivate physicians to advise these patients to undergo more systematic screening for SMI using this technique.  相似文献   

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BACKGROUND: Patients with apical hypertrophic cardiomyopathy (ACM) are often referred for myocardial perfusion single photon emission computed tomography (SPECT) as a result of marked T-wave inversion and chest pain syndromes. Stress perfusion defects have been reported in ACM, but the characteristic SPECT pattern as well as the typical findings on volume-weighted polar maps has not been described. METHODS AND RESULTS: Dual-isotope rest (thallium 201) and exercise or adenosine stress (technetium 99m tetrofosmin) myocardial perfusion SPECT was performed in 11 patients with ACM, including 8 with either normal coronary arteriography (n = 5) or a low pretest probability of coronary artery disease (CAD) (n = 3), and 14 control patients with concentric left ventricular hypertrophy. An 8-pixel-diameter circular region of interest was used to quantitatively compare apical and septal counts on CEqual volume-weighted polar maps. A characteristic "Solar Polar" map pattern resulting from the increased apical counts was present in each ACM patient at rest, with a mean apical-septal ratio of 1.39 +/- 0.17 (range, 1.23-1.62, P <.01 vs concentric left ventricular hypertrophy group). With stress, there was a significant decrease in the apical-septal ratio (0.96 +/- 0.18, P <.001 vs rest) in the ACM subgroup without CAD. CONCLUSION: Patients with ACM demonstrate a newly described "Solar Polar" map pattern at rest, as well as relative apical ischemia on the stress images even in the absence of CAD.  相似文献   

7.
PURPOSE: To prospectively evaluate, by using positron emission tomography (PET) and magnetic resonance (MR) imaging, the interrelationships between regional myocardial fibrosis, perfusion, and contractile function in patients with idiopathic dilated cardiomyopathy (DCM). MATERIALS AND METHODS: The study protocol was approved by the hospital ethics committee, and all subjects gave written informed consent. Sixteen patients with idiopathic DCM (mean age, 54 years +/- 11 [standard deviation]; nine men) and six healthy control subjects (mean age, 28 years +/- 2; five men) were examined with PET and MR tissue tagging. Oxygen 15-labeled water and carbon monoxide were used as tracers at PET to assess myocardial blood flow (MBF) and the perfusable tissue index (PTI), which is inversely related to fibrosis. MBF was determined at rest and during pharmacologically induced hyperemia. Maximum circumferential shortening (E(cc)) was determined with MR tissue tagging. Student t tests were performed for comparison of data sets, and linear regression was used to investigate the association between parameters. RESULTS: Mean global hyperemic MBF (2.23 mL/min/mL +/- 0.73), E(cc) (-10.5% +/- 2.9), and PTI (0.95 +/- 0.10) were lower in the patients with DCM than in the control subjects (4.33 mL/min/mL +/- 0.85, -17.4% +/- 0.6, and 1.09 +/- 0.12, respectively; P < .05 for all). In the patients with DCM, regional PTI was related to E(cc) (r = -0.21, P = .009) but not to resting or hyperemic MBF. Furthermore, regional E(cc) was correlated to both resting (r = -0.28, P = .004) and hyperemic MBF (r = -0.29, P < .001). In addition, the ratio of left ventricular end-diastolic volume to mass, as a reflection of wall stress, was related to global hyperemic MBF (r = -0.52, P = .047) and to global E(cc) (r = 0.69, P = .003). CONCLUSION: In idiopathic DCM, the extent of myocardial fibrosis is related to the impairment in contractile function, whereas fibrosis and perfusion do not seem to be interrelated. The degree of impairment of hyperemic myocardial perfusion is related to contractility and end-diastolic wall stress.  相似文献   

8.
Annals of Nuclear Medicine - Information on the relationship between myocardial damage assessed by myocardial scintigraphy and prognosis in patients with Anderson–Fabry disease (AFD) is...  相似文献   

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Aim

To estimate the prevalence of silent myocardial ischemia (SMI) in patients with Behçet’s disease (BD) and to identify a subgroup of patients at higher risk for the presence of SMI. Materials and Methods We evaluated 41 patients (mean age 42.8 ± 12.3 years) with BD and 35 healthy control subjects. Treadmill exercise test and thallium-201 myocardial perfusion single photon emission computed tomography (SPECT) were performed in all subjects. Coronary angiography was performed in all patients with a diagnosis of SMI in Behçet’s group.

Results

All subjects had normal resting electrocardiograms. Eight patients with BD (19.5%) had evidence of ischemia on exercise testing and myocardial perfusion SPECT. Only one SMI positivity (2.9%) was recorded in the control group. Significant coronary stenosis was not found with coronary angiography in the patients with a diagnosis of SMI in Behçet’s group. SMI positivity was recorded in 2 of 18 female patients (11%) and in 6 of 23 male patients (26.1%) with BD (p = 0.429). The mean duration of BD was 13.8 ± 2.6 years in patients with SMI and 7 ± 4.1 in patients without it (p < 0.001). Seven of the 8 patients (87.5%) with SMI had a duration of BD of greater than 10 years.

Conclusions

The results of this study show that the prevalence of SMI is high in patients with BD. Based on our findings, screening with myocardial perfusion scintigraphy may be recommended for patients with duration of BD greater than 10 years.  相似文献   

11.
BackgroundPatent foramen ovale (PFO) in patients with acute pulmonary embolism (PE) represents a risk factor for mortality, but this has not been evaluated for CT pulmonary angiography (CTPA). The purpose of the present study was to assess the relationship between PFO and mortality in patients with acute PE diagnosed on CTPA.Materials and methodsThis retrospective study included 268 adults [173 women, mean age 61 (range 22–98) years] diagnosed with acute PE on non-ECG-gated 64-slice CTPA in 2012 at our medical center. The images were reviewed for PFO by a panel of cardiothoracic radiologists with an average of 11 years of experience (range 1–25 years). CT signs of right heart strain and PE level were noted. Transthoracic echocardiograms (TTE), when available (n = 207), were reviewed for PFO by a cardiologist with subspecialty training in advanced imaging and with 3 years of experience. The main outcome was 30-day mortality. Fischer's exact test was utilized to compare mortality.ResultsPFO prevalence on CTPA was 22% (58/268) and 4% (9/207) on TTE. Overall 30-day mortality was 6% (16/268), 9% (5/58) for patients with PFO and 5% (11/210) for those without (p = 0.35). CT signs of right heart strain trended with higher mortality, but statistically significant only for hepatic vein contrast reflux [14% (6/44) vs 4% (10/224), p = 0.03]; right ventricular (RV) to left ventricular (LV) diameter ratio >1 [8% (13/156) vs RV:LV ≤ 1 3% (3/112), p = 0.07], septal bowing [10% (4/42) vs without 5% (12/226), p = 0.30].ConclusionPFO was demonstrated on CTPA in a proportion similar to the known population prevalence, while routine TTE was less sensitive. Mortality was non-significantly higher in patients with acute PE and PFO in this moderate-sized study. A larger study to answer this clinically important question is worthwhile.  相似文献   

12.

Objective

Since myocardial perfusion imaging (MPI) with conventional sodium iodine (NaI) device has low spatial resolution, there have been some cases in which small structures such as non-transmural myocardial infarction could not be properly detected. The purpose of this study was to evaluate potential usefulness of cadmium–telluride (CdTe) semiconductor detector-based high spatial resolution gamma cameras in detecting myocardial infarction sites, especially non-transmural infarction.

Methods

A total of 38 patients (mean age ± SD: 64 ± 21 year) who were clinically diagnosed with acute myocardial infarction were included. Twenty-eight cases of them were with ST segment elevation myocardial infarction (STEMI) and 10 cases with non-ST segment elevation myocardial infarction (NSTEMI). In all patients, myocardial perfusion single photon emission computed tomography images were acquired with Infinia (NaI device) and R1-M (CdTe device), and the images were compared concerning the detectability of acute myocardial infarction sites.

Results

The detection rates of the myocardial infarction site in cases with STEMI were 100 % both by NaI and CdTe images. In cases with NSTEMI, detection rate by NaI images was 50 %, while that of CdTe images was 100 % (p = 0.033). The summed rest score (SRS) value derived from CdTe images was significantly higher than that from NaI images in cases with STEMI [NaI images: 12 (7–18) versus CdTe images: 14 (9–20)] (p < 0.001). SRS derived from CdTe images was significantly higher than that derived from NaI images in cases with NSTEMI [NaI images: 2 (0–5) versus CdTe images: 6 (6–8)] (p = 0.006).

Conclusions

These results indicate that MPI using CdTe-semiconductor device will provide a much more accurate assessment of acute myocardial infarction in comparison to current methods.  相似文献   

13.
OBJECTIVES: Myocardial perfusion SPECT is frequently affected by artefacts related to abdominal activity. Metoclopramide has been suggested to relieve this, but two previous studies have shown conflicting results. METHODS: Ninety-five patients received 10 mg metoclopramide orally after injection of 99mTc-tetrofosmin for the stress scan and 86 patients had metoclopramide after their rest injection. A control group of 82 patients did not receive metoclopramide. Scans were evaluated visually by three readers. RESULTS: Metoclopramide given before the stress scan led to abdominal activity being visually better in 16 scans, worse in 10, and unchanged in 67 scans, compared to the same patient's rest scan without metoclopramide administration. Metoclopramide administered before the rest scan resulted in abdominal activity in 11 scans being visually better, in 19 worse, and 53 scans were deemed unchanged. These differences were not significant. The number of repeat stress or rest scans was not significantly different between patients who had received metoclopramide and those who had not. The administration of metoclopramide, irrespective of whether it was given before the stress or rest scan, made no significant difference to inferior wall-to-abdomen count ratio. CONCLUSION: Neither qualitative nor quantitative analysis showed an effect of metoclopramide on abdominal activity in myocardial perfusion SPECT.  相似文献   

14.
《Radiography》2023,29(2):327-332
IntroductionTo establish if the CT dataset acquired during the stress element of myocardial perfusion imaging can be fused to the subsequent rest scan to reduce radiation doses from these procedures.Methods86 rest scans were processed and evaluated using a self-designed project specific tool. Recording processing time, the time between the two data sets selected for fusion and assessing radiographic reports to ensure produced images were of diagnostic quality.Results70% of fused scans were acquired 6–7 days apart; the mean (SD) processing time was calculated as 2.03 (0.36) minutes. The Pearson's correlation between these two variables was determined to be 0.22, showing a slight positive correlation although not statistically significant. 100% of the images produced were of diagnostic quality.ConclusionRest scans can be fused to a previously acquired CT, careful consideration should be given when positioning the patient and to the time interval between acquiring the two data sets, departmental guidelines can assist with this. Staff training may also be beneficial to ensure staff can assess if data sets are fusible prior to completing a scan.Implications for practiceThis data provides evidence that retrospective fusion can reduce patient radiation doses in myocardial perfusion imaging without compromising diagnostic outcomes. Dose optimisation is an essential part of the ionising radiation (medical exposure) regulations therefore retrospective fusion should be considered in practice to ensure departmental compliance, although it is noteworthy this study is solely based in a single centred one camera department.  相似文献   

15.
ObjectivesTo determine whether baseline physical tests have a prognostic value on patient-reported outcomes in Achilles tendinopathy.DesignProspective cohort study, secondary analysis of data from a randomized trial.MethodsPatients with chronic midportion Achilles tendinopathy performed a progressive calf muscle exercise program. At baseline and after 2, 6, 12 and 24 weeks, patients completed the Victorian Institute of Sports Assessment—Achilles questionnaire and performed the following physical tests: ankle dorsiflexion range of motion with a bent knee or an extended knee, calf muscle strength, jumping height and pain on palpation (Visual Analogue Scale; 0–100) and after 10 hops (Visual Analogue Scale-10-hops). Associations between baseline test results and improvement (Victorian Institute of Sports Assessment—Achilles scores) were determined using a Mixed Linear Model.Results80 patients were included. The mean Victorian Institute of Sports Assessment—Achilles score improved 20 points (95 % confidence interval, 16–25, P < .001) after 24 weeks. There were significant associations between the baseline ankle dorsiflexion range of motion with a bent knee (β 0.2, 95 % confidence interval 0.001 to 0.3, P = .049), the baseline pain provocation tests (Visual Analogue Scale palpation: β − 0.2; 95 % confidence interval: − 0.4 to − 0.1; P < .001, Visual Analogue Scale-10-hops: β − 0.3; 95 % confidence interval: − 0.4 to − 0.2; P < .001) and the change in the Victorian Institute of Sports Assessment—Achilles score.ConclusionsIn patients with chronic midportion Achilles tendinopathy, easy-to-perform pain provocation tests have a clinically relevant prognostic value on patient-reported improvement. Patients with less pain during pain provocation tests at baseline have a better improvement in pain, function and activities after 24 weeks than patients with high baseline pain scores.  相似文献   

16.
Purpose This study assessed the incremental value of dobutamine stress 99mTc-tetrofosmin single-photon emission computed tomography (SPECT) for the prediction of cardiac events in diabetic patients with limited exercise capacity.Methods The study population comprised 125 consecutive diabetic patients (mean age 61±9 years, 61% men) who were unable to perform an exercise test and underwent dobutamine 99mTc-tetrofosmin SPECT. Follow-up was successful in 124 (99%) patients. Three patients who underwent early revascularisation (within 60 days) were excluded. End-points during follow-up were cardiac death and non-fatal myocardial infarction.Results An abnormal scan (with the presence of reversible or fixed perfusion defects) was observed in 76 (63%) patients. During the follow-up (3.4±1.5 years), 36 patients died (19 cardiac deaths) and four patients had non-fatal myocardial infarction. Cardiac death occurred in one of 49 (2%) patients with a normal myocardial perfusion study and in 18 of 75 (24%) patients with an abnormal study (p<0.001). Abnormal scan was incremental to the clinical parameters in predicting cardiac death (2=48 vs 39, p<0.05) and hard cardiac events (2=50 vs 43, p<0.05).Conclusion Dobutamine stress 99mTc-tetrofosmin SPECT provides prognostic information additional to clinical data for the prediction of cardiac death and hard cardiac events in diabetic patients unable to perform an exercise test.  相似文献   

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BACKGROUND: This study investigates the clinical performance of routine 201Tl gated single photon emission computed tomographic (201Tl GSPECT) myocardial perfusion imaging. Equilibrium radionuclide angiography (ERNA) was used as the standard for comparison. METHODS AND RESULTS: One hundred and seventy-two consecutive patients were submitted to both myocardial 201Tl GSPECT imaging, at stress and in redistribution, and ERNA. Left ventricular ejection fractions (LVEF) and regional wall motion were assessed from both stress and redistribution 201Tl GSPECT datasets, and from ERNA. Linear regression analysis showed a good correlation between LVEF calculated by ERNA and 201Tl GSPECT (r=0.73 at stress, r=0.75 in redistribution, P<0.0001). However, the 95% prediction intervals of 201Tl GSPECT LVEF from ERNA LVEF were wide (minimum 35.4% at stress and 33.2% in redistribution). Moreover, a difference in LVEF > or =10% between ERNA and 201Tl GSPECT was found in 26.4% of cases at stress and 28.6% of cases in redistribution. A fair agreement between ERNA and 201Tl GSPECT was found in regional wall motion assessment in segments with normal or mildly reduced tracer uptake (kappa=0.32 at stress and kappa=0.33 in redistribution). In segments with moderately to severely reduced tracer uptake, a moderate agreement was found in regional wall motion assessment between ERNA and 201Tl GSPECT (kappa=0.44 at stress and kappa=0.42 in redistribution). CONCLUSIONS: Left ventricular function may be misinterpreted in a significant proportion of patients if the calculation of LVEF is based on 201Tl GSPECT. Moreover, the evaluation of regional wall motion by 201Tl GSPECT appears unsatisfactory.  相似文献   

19.
Predicting the effect of #-blockade therapy on the clinical outcome of patients with dilated cardiomyopathy (DCM) is difficult prior to the initiation of therapy. Myocardial fatty acid metabolism has been shown to be impaired in patients with DCM. We examined whether the extent of myocardial injury, as assessed by iodine-123 15-(p-iodophenyl)-3-R,S-methylpentadecanoic acid (BMIPP) myocardial scintigraphy, is related to the response of patients with DCM to #-blockade therapy. Thirty-seven patients with DCM were examined using BMIPP myocardial scintigraphy before and after 6 months of treatment with metoprolol. Myocardial BMIPP uptake (%BM uptake) was estimated quantitatively as a percentage of the total injected count ratio. The left ventricular end-diastolic and end-systolic dimensions (LVDd, LVDs) and ejection fraction (LVEF) were also evaluated. The patients were divided into two groups according to their functional improvement (>10% elevation of LVEF) after 6 months of metoprolol therapy. Twenty-eight patients responded to the therapy, while nine did not. Prior to the therapy, no significant differences in LVDd, LVDs or LVEF were observed between the responders and non-responders. However, the %BM uptake was significantly lower in the non-responders than in the responders (1.0%ǂ.2% vs 2.1%ǂ.5%, P<0.001). The %BM uptake could be used to distinguish the responders from the non-responders with a sensitivity of 0.93 and a specificity of 1.00 at a threshold value of 1.4. After the metoprolol therapy, the %BM uptake improved significantly in the responders (2.5%ǂ.5%, P<0.01) but did not change in the non-responders. These results indicate that myocardial BMIPP uptake could predict the response of DCM patients to #-blockade therapy.  相似文献   

20.

Background

Left ventricular (LV) remodeling has adverse effects on the prognosis of patients with myocardial infarction (MI). The aim of this study is to identify the risk factors of LV remodeling in MI patients by radionuclide myocardial imaging.

Methods and Results

This retrospective study consisted of 92 patients who had a history of definite prior MI on ECG and underwent both resting gated single photon emission computed tomography (SPECT) myocardial perfusion imaging (MPI) and positron emission tomography (PET) myocardial metabolism imaging. LV remodeling was defined as > mean + 2SD of LV end-diastolic volume index (LVEDVi) in the normal database. LV enlargement, cardiac dysfunction, wall thickening abnormalities expressed as summed thickening score (STS) were more severe in the old MI patients as compared to those with subacute MI. STS (Odds ratio, 1.296; P = .004) and the proportion of segments with reduced wall thickening in segments with normal perfusion (Odds ratio, 1.110; P = .001) were identified as the independent factors of LV remodeling in subacute and old MI patients in the multivariate binary regression model. Total perfusion deficit (TPD), viable myocardium, scar, and the proportion of segments with reduced wall thickening in segments with decreased perfusion showed strong correlation with LV remodeling in the univariate regression model as well.

Conclusions

LV remodeling in old MI patients is more extensive and severe than that in subacute MI patients. LV wall thickening abnormalities as expressed by STS and the proportion of segments with reduced wall thickening in segments with normal perfusion are the independent risk factors of LV remodeling in MI patients.
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