Development of a Model Based on Delta-Radiomic Features for the Optimization of Head and Neck Squamous Cell Carcinoma Patient Treatment.

Background and Objectives: To our knowledge, this is the first study that investigated the prognostic value of radiomics features extracted from not only staging 18F-fluorodeoxyglucose positron emission tomography (FDG PET/CT) images, but also post-induction chemotherapy (ICT) PET/CT images. This study aimed to construct a training model based on radiomics features obtained from PET/CT in a cohort of patients with locally advanced head and neck squamous cell carcinoma treated with ICT, to predict locoregional recurrence, development of distant metastases, and the overall survival, and to extract the most significant radiomics features, which were included in the final model. Materials and Methods: This retrospective study analyzed data of 55 patients. All patients underwent PET/CT at the initial staging and after ICT. Along the classical set of 13 parameters, the original 52 parameters were extracted from each PET/CT study and an additional 52 parameters were generated as a difference between radiomics parameters before and after the ICT. Five machine learning algorithms were tested. Results: The Random Forest algorithm demonstrated the best performance (R2 0.963-0.998) in the majority of datasets. The strongest correlation in the classical dataset was between the time to disease progression and time to death (r = 0.89). Another strong correlation (r ≥ 0.8) was between higher-order texture indices GLRLM_GLNU, GLRLM_SZLGE, and GLRLM_ZLNU and standard PET parameters MTV, TLG, and SUVmax. Patients with a higher numerical expression of GLCM_ContrastVariance, extracted from the delta dataset, had a longer survival and longer time until progression (p = 0.001). Good correlations were observed between Discretized_SUVstd or Discretized_SUVSkewness and time until progression (p = 0.007). Conclusions: Radiomics features extracted from the delta dataset produced the most robust data. Most of the parameters had a positive impact on the prediction of the overall survival and the time until progression. The strongest single parameter was GLCM_ContrastVariance. Discretized_SUVstd or Discretized_SUVSkewness demonstrated a strong correlation with the time until progression.

Use of 18F-FDG PET/CT Imaging for Radiotherapy Target Volume Delineation after Induction Chemotherapy and for Prognosis of Locally Advanced Squamous Cell Carcinoma of the Head and Neck.

Background and objectives: Induction chemotherapy (ICT) before definitive chemoradiation (CRT) gives high response rates in locally advanced squamous cell carcinoma of the head and neck (LA-SCCHN). However, pre-ICT gross tumor volume (GTV) for radiotherapy (RT) planning is still recommended. As 18F-FDG PET/CT has an advantage of biological tumor information comparing to standard imaging methods, we aimed to evaluate the feasibility of 18F-FDG PET/CT-based post-ICT GTV delineation for RT planning in LA-SCCHN and to assess the prognostic value of PET parameters: maximum standardized uptake value (SUVmax), metabolic tumor volume (MTV) and total lesion glycolysis (TLG). Methods: 47 LA-SCCHN patients were treated with 3 cycles of ICT (docetaxel, cisplatin, and 5-fluorouracil) followed by CRT (70 Gy in 35 fractions with weekly cisplatin). Pre- and post-ICT PET/CT examinations were acquired. Planning CT was co-registered with post-ICT PET/CT and RT target volumes were contoured according to post-ICT PET. Post-ICT percentage decrease of SUVmax, MTV and TLG in primary tumor and metastatic regional lymphnodes (LN) was counted. Loco-regional failure patterns, 3-year progression free (PFS) and overall survival (OS) were evaluated. Results: 3-year PFS and OS rates for study population were 67% and 61% respectively. 31.9% of patients progressed loco-regionally. All progress was localized in high-to-intermediate dose (60⁻70 Gy) RT volumes and none in low dose (50 Gy) volumes. Decrease of SUVmax ≥ 74% (p = 0.04), MTV ≥ 68% (p = 0.03), TLG ≥ 76% (p = 0.03) in primary tumor, and LN TLG decrease ≥ 74% (p = 0.03) were associated with PFS. Decrease of primary tumor SUVmax ≥ 74% (p = 0.04), MTV ≥ 69% (p = 0.03), TLG ≥ 74% (p = 0.02) and LN TLG ≥ 73% (p = 0.02) were prognostic factors for OS. Conclusions: According to our results, 18F-FDG PET/CT-based post-ICT GTV delineation is feasible strategy without negative impacts on loco-regional control and survival. Percentage decrease of metabolic PET parameters SUVmax, MTV and TLG has a prognostic value in LA-SCCHN.

The Role of 18-Fluoro-2-Deoxy-Glucose Positron Emission Tomography/Computed Tomography as Response and Prognosis Predictive Factor of Concurrent Chemoradiotherapy after Induction Chemotherapy in Head and Neck Squamous Cell Carcinoma: A Prospective Study.

Background and objectives: The importance of induction chemotherapy (ICT) followed by concurrent chemoradiotherapy (CCRT) has been re-established in recent years aiming at fewer metastatic sites and better control of the disease. We prospectively studied the possibility of early prediction of overall survival (OS) and progression-free survival (PFS) after 3 cycles of chemotherapy with doxetacel, cisplatin and 5-fluorouracil using 18-fluoro-2-deoxy-glucose positron emission tomography computed tomography (18F-FDG PET/CT) in patients with head and neck squamous cell cancer. To our knowledge, this is the first such study. Materials and Methods: Thirty-five patients were studied. They underwent an 18F-FDG PET/CT examination twice: a day before ICT and 10⁻14 days after the last cycle of ICT. Tumor-standardized uptake value (SUVmax) and hypermetabolic tumor volume were measured on both scans. The mean age of patients was 56.5 years. Complete responses to CCRT PFS and OS were calculated. Results: Our results showed that a decrease of ≥30% in the SUVmax value after ICT was a prognostic factor of tumor response to PFS and OS (p = 0.026 and p = 0.021). The groups of patients with a SUVmax between 10 and 14.5 in the primary tumor on a pre-ICT 18F-FDG PET/CT scan had statistically shorter PFS and OS (p = 0.001, p = 0.006) when compared with other groups of patients with SUVmax less than 10 or SUVmax more than 14.5. A decrease of less than 55% of hypermetabolic tumor volume of the primary tumor was significantly related to poor prognosis in PFS and OS (p = 0.033, p = 0.017). Conclusions: SUVmax and hypermetabolic tumor volume measured on 18F-FDG PET/CT after ICT might be valuable prognostic tools for predicting OS and PFS and, thus, for the selection of patients with head and neck cancer who will benefit from CCRT.

Positron Emission Tomography in the Diagnosis and Management of Coronary Artery Disease.

Cardiac positron emission tomography (PET) and positron emission tomography/computed tomography (PET/CT) are encouraging precise non-invasive imaging modalities that allow imaging of the cellular function of the heart, while other non-invasive cardiovascular imaging modalities are considered to be techniques for imaging the anatomy, morphology, structure, function and tissue characteristics. The role of cardiac PET has been growing rapidly and providing high diagnostic accuracy of coronary artery disease (CAD). Clinical cardiology has established PET as a criterion for the assessment of myocardial viability and is recommended for the proper management of reduced left ventricle (LV) function and ischemic cardiomyopathy. Hybrid PET/CT imaging has enabled simultaneous integration of the coronary anatomy with myocardial perfusion and metabolism and has improved characterization of dysfunctional areas in chronic CAD. Also, the availability of quantitative myocardial blood flow (MBF) evaluation with various PET perfusion tracers provides additional prognostic information and enhances the diagnostic performance of nuclear imaging.

Diagnostic challenges in multiple system atrophy.

Multiple system atrophy is a progressive neurodegenerative disorder that is characterized by autonomic failure, cerebellar ataxia and parkinsonism syndrome in various combinations. In spite of the presence of well-established clinical criteria for multiple system atrophy, ante-mortem diagnosis is difficult. In our case report, we present a 78-year-old female patient who presented with early progressive aphasia and severe autonomic dysfunction. Two years after appearance of the first symptoms, she fulfilled all the major criteria for probable multiple system atrophy with rapid progression. In addition, brain magnetic resonance imaging and fluorodeoxyglucose-positron emission tomography findings were more typical for progressive supranuclear palsy. Clinically differentiating multiple system atrophy from progressive supranuclear palsy and other similar neurodegenerative disorders may be challenging in all stages of the disease, especially with atypical disease presentation.

Prognostic value of myocardial perfusion abnormalities for long-term prognosis in patients after coronary artery bypass grafting.

AIMS: The objective was to evaluate the prognostic value of exercise myocardial perfusion scintigraphy (MPS) in patients who underwent coronary artery bypass grafting (CABG). SUBJECTS AND METHODS: A retrospective, one-center study of 361 patients with multivessel coronary artery disease was carried out. All the patients underwent MPS after CABG due to worsened health status. MPS was performed at 4.5 years standard deviation (SD: 0.2), based on symptoms. MPS was carried out using Tc-99m methoxy isobutyl isonitrile and following a 1-day protocol (stress-rest). The end points were analyzed at 6.5 years (SD: 3.3) after MPS, on the average. STATISTICAL ANALYSIS USED: SPSS software for Windows, version 13.0. The t-test or the χ(2)-test was used. Survival times were calculated. A multivariate Cox proportional hazards model was developed. RESULTS: During the follow-up, death occurred in 54 patients, and 37 patients experienced major adverse cardiovascular events (MACE). In the multivariate analysis, advanced age hazard ratio (HR: 1.45; 95% confidence interval [CI]: 1.4-2.02; P = 0.027), previous myocardial infarction (HR: 3.17; 95% CI: 1.22-8.2; P = 0.018), left ventricular ejection fraction of <40% (HR: 2.16; 95% CI: 1.2-3.89; P = 0.01), and the summed stress score (SSS) of ≥4 (HR: 1.87; 95% CI: 1.02-3.41; P = 0.04) were independent predictors of all-cause death. The summed difference score (SDS) was the only independent predictor of MACE (HR: 1.26; 95% CI: 1.06-1.48; P = 0.034). CONCLUSIONS: The parameters of MPS were found to have prognostic value in the long-term period after CABG. Advanced age, previous myocardial infarction, decreased left ventricular ejection fraction, and the abnormal SSS were associated with an increased risk of all-cause death. The SDS was found to be the only significant risk factor for MACE.

Perioperative single photon emission computed tomography in predicting survival of malignant glioma patients.

Single photon emission computed tomography (SPECT) is widely used in the evaluation of glioma patients and has been demonstrated to correlate with glioma malignancy and proliferation indexes. The aim of this study was to evaluate the association between perioperative technetium-99m-methoxyisobutylisonitrile ((99m)Tc-MIBI) uptake on SPECT scans and survival of malignant glioma patients. A total of 17 patients (11 males and 6 women; mean age, 62.2±8.4 years) with histologically confirmed malignant gliomas (16 glioblastoma multiforme and 1 gliosarcoma) underwent (99m)Tc-MIBI SPECT scans 2.8±1.9 days before surgery and 9.8±1.5 days after surgery. The total intensity index (TII) that corresponds to the area and intensity of tracer uptake was calculated before and after surgery. In addition, the change of TII before versus after surgery (Δ TII) was calculated. The overall survival (OS) was defined as the period between the date of surgery and the date of death. The median overall survival time was 12.4 months, ranging from 1.4 to 88 months; there were nine (45%) 12-month survivors. In univariate analyses using a log-rank test, worse OS was significantly associated with higher preoperative TII (≥12), higher postoperative TII (≥6), lower Δ TII (<50%) and higher number of neurological symptoms prior to surgery (≥4). In multivariate analyses, higher postoperative TII, a greater number of neurological symptoms and female gender were found to be factors with independent prognostic value of OS. Patients who survived more than 12 months following surgery had a significantly lower postoperative TII, higher Δ TII and greater rate of gross total resection compared to patients who survived less than 12 months following surgery. Higher peri-operative tracer uptake and lower decrease of tracer uptake following surgery (suggesting less radical resection) were associated with worse OS of malignant glioma patients. Our results suggest that SPECT may be used to predict survival of malignant glioma patients; however, further studies using larger samples are required.

Introduction of novel semiquantitative evaluation of (99m)Tc-MIBI SPECT before and after treatment of glioma.

BACKGROUND AND OBJECTIVE. There is a need for objective semiquantitative indexes for the evaluation of results of single-photon emission tomography (SPECT) in patients with brain glioma. The aim of this study was to validate the total size index (TSI) and total intensity index (TII) based on technetium-99m-methoxyisobutylisonitrile ((99m)Tc-MIBI) SPECT scans to discriminate the patients with high-grade glioma versus low-grade glioma and to evaluate the changes of viable glioma tissue by the means of TSI and TII after surgery and after radiation treatment. MATERIAL AND METHODS. Thirty-two patients (mean age, 55 years [SD, 18]; 20 men) underwent a (99m)Tc-MIBI-SPECT scan before surgery. Of these patients, 27 underwent a postoperative (99m)Tc-MIBI-SPECT scan and 7 patients with grade IV glioma underwent a third (99m)Tc-MIBI-SPECT scan after radiation treatment. TII that corresponds to the area and intensity of tracer uptake and TSI that corresponds to the area of tracer uptake were calculated before surgery, after surgery, and after radiation treatment. RESULTS. The TII and TSI were found to be valid in discriminating the patients with high-grade versus low-grade glioma with optimal cutoff values of 3.0 and 2.5, respectively. Glioma grade correlated with the preoperative TSI score (r=0.76, P<0.001) and preoperative TII score (r=0.64, P<0.001). There was a significant decrease in the TII and TSI after surgery in patients with grade IV glioma. After radiation treatment, there was a significant increase in the TII in patients with grade IV glioma. CONCLUSIONS. TSI and TII were found to be reliable in discriminating the patients with high-grade versus low-grade glioma and allowed for the semiquantitative evaluation of change in viable glioma tissue after surgery and after radiation treatment in patients with grade IV glioma.

[Data of coronary angiography and normal stress myocardial perfusion scintigraphy]. / Normali kruvio miokardo perfuzija ir vainikiniu arteriju bukle.

OBJECTIVE: To determine informativity of clinical variables in predicting significant coronary artery disease in patients with chest pain and normal stress myocardial perfusion scintigraphy. MATERIAL AND METHODS: This study was a retrospective analysis of data of coronary angiography performed in 84 patients with chest pain and normal stress myocardial perfusion scintigraphy during 2000-2007. Single-photon emission computed tomography was performed following a one-day protocol (stress-rest). A 5-point (0-4) scoring system in a 20-segment model was used for interpretation of results. Myocardial perfusion was considered normal if the sum of stress scores was 0 to 3. RESULTS: High pretest probability and informative exercise-terminating criteria were documented in 25% and 45.2% of patients, respectively. Significant coronary artery disease (stenosis ≥ 75%) was determined in 26 (31%) patients with normal myocardial perfusion scintigraphy: 15 (17.9%) patients had coronary artery disease of a single vessel, 5 (6%) of two vessels, and 6 (7.1%) of three vessels. Univariate logistic regression analysis showed that patients with typical angina and high pretest probability were more likely to have significant stenosis of one to three arteries (odds ratios, 3.8; P=0.008 and 3.43; P=0.023, respectively). Three-vessel disease was more often documented in patients with typical angina (odds ratio, 11.2; P=0.009), high pretest probability (odds ratio, 7.93; P=0.018), and signs of ischemia during exercise test (odds ratio, 6.4; P=0.037). CONCLUSION: Patients with typical angina, high pretest probability, and signs of ischemia during exercise test have an increased probability of having significant coronary artery disease despite normal stress myocardial perfusion scintigraphy; therefore, this group of patients should undergo coronary angiography.

The value of 99mTc-MIBI myocardial perfusion imaging in differentiation of heart failure conditioned by global left ventricular systolic impairment.

OBJECTIVE: The global left ventricular systolic impairment with left ventricular dilatation can manifest due to idiopathic dilated cardiomyopathy or ischemic heart disease and can present a similar clinical picture of severe heart failure. The aim of our investigation was to assess a differential diagnostic value of resting (99m)Tc-MIBI myocardial perfusion defects in evaluation of the etiology of heart failure. MATERIAL AND METHODS: The data of 2D echocardiography, coronary angiography, and myocardial gated single photon emission computed tomography with (99m)Tc-MIBI investigation were evaluated in 43 patients with global left ventricular systolic impairment, characterized by left ventricular end-diastolic diameter of > or =65 mm and ejection fraction of < or =40%. The idiopathic dilative cardiomyopathy was diagnosed in 26 patients (Group 1) and ischemic heart failure in 17 patients (Group 2). The area and the degree (severity) of myocardial perfusion defects (AMPD and DMPD) at rest in regions supplied by three coronary arteries were evaluated in all the patients. RESULTS: The area of perfusion defects in the left anterior descending (LAD) and right coronary artery (RCA) regions in dilative cardiomyopathy patients was smaller than in ischemic heart failure patients (1.43+/-0.9 vs 2.53+/-0.53, P=0.001, and 2.19+/-0.6 vs 2.82+/-0.56, P=0.02). The degree of perfusion defects was also less severe in the same circulation regions (1.39+/-0.93 vs 2.59+/-0.6, P=0.01, and 1.6+/-0.46 vs 2.71+/-0.15, P=0.001). We have designed a logistic regression model expressed by formula x=2.52AMPD(rca)+2.47AMPD(lad)+2.21DMPD(rca). Idiopathic dilative cardiomyopathy was predicted when x was < or =16 and ischemic heart failure when x was >16. The sensitivity in predicting idiopathic dilative cardiomyopathy was 94.44%, and the specificity was 88.24%. CONCLUSION: The difference in the area and degree of (99m)Tc-MIBI myocardial perfusion defects at rest in patients with heart failure caused by idiopathic dilative cardiomyopathy or ischemic heart failure is measurable and has a predictive value for differentiation of the etiology of global left ventricular systolic impairment.

The role of 99mTc-depreotide in the management of neuroendocrine tumours.

BACKGROUND: In-pentetreotide scan (OctreoScan) is a widely available agent with high sensitivity for imaging neuroendocrine tumours. Negative In-pentetreotide poses diagnostic as well as therapeutic problems in terms of staging and consideration of targeted radionuclide therapy. AIM: To assess the role of Tc-depreotide in patients with negative or weakly positive OctreoScan (Krenning score< or =1; measured on a scale range 0-4). To determine the usefulness of Tc-depreotide scintigraphy for highlighting lesions that may be missed by OctreoScan and/or CT/MRI imaging. STUDY DESIGN: Prospective analysis of 25 patients with neuroendocrine tumours, with negative or weakly positive In-pentetreotide scans, who were consecutively enrolled to undergo In-pentetreotide and Tc-depreotide imaging. The results were compared with either CT or MRI scans. RESULTS: Histology was available for 20 of 25 patients: of these 40% had high-grade tumours (cellular proliferation marker Ki-67 score >20%), a further 35% had intermediate-grade tumours (Ki-67 2-20%), and the remaining 25% had low-grade tumours (Ki-67 <2%). Fifty-two percent of patients had completely negative and 48% had weakly positive OctreoScan results. Thirty-two percent of these same patients had significantly positive Tc-depreotide scans (Krenning score> or =2), with the histology demonstrating intermediate-grade or high-grade tumours. CONCLUSION: Tc-depreotide imaging has low sensitivity but is useful in a one-third of OctreoScan-negative patients, displaying significantly better uptake than In-pentetreotide in this patient group. It aids diagnosis by highlighting lesions not seen by OctreoScan and/or CT/MRI imaging, and can possibly identify a group of patients amenable to therapy with radionuclide agents, such as SOM230, targeting somatostatin receptor subtypes 2, 3 and 5.

[Evaluation of clinical parameters and myocardial perfusion scintigraphy findings in patients with suspected coronary artery disease, abnormal resting electrocardiogram, and noninterpretable exercise test]. / Klinikiniu rodmenu ir miokardo perfuzijos sutrikimu ivertinimas pacientams, kuriems itariama isemine sirdies liga, pakitusi ramybes elektrokardiograma ir neinformatyvus veloergometrijos tyrimas.

UNLABELLED: The aim of this work was to estimate the impact of clinical variables on predicting stress myocardial perfusion abnormalities in patients with suspected coronary artery disease, abnormal resting electrocardiogram, and noninterpretable exercise test. MATERIAL AND METHODS: The clinical variables and stress myocardial perfusion data were analyzed in 370 patients (157 males and 213 females) with suspected coronary artery disease and abnormal resting electrocardiogram. All patients underwent (99m)Tc-methoxyisobutylisonitrile (MIBI) scintigraphy following a one-day protocol (stress-rest). The bicycle exercise test was considered noninterpretable when the age-predicted peak heart rate was not achieved, and ischemic signs were not detected. RESULTS: One hundred sixty (43.2%) patients had noninterpretable bicycle exercise test. Pathological stress myocardial perfusion defects (reversible and fixed) were more often present in patients with noninterpretable than in patients with informative exercise test (63.1 and 50.0%, respectively, p<0.01). Univariate analysis showed that reversible perfusion defects were more frequent in men than in women (p<0.00001, odds ratio 9.6), in patients with pre-existing left bundle-branch block (p<0.02, odds ratio 3.4), and in cases when sufficient working capacity (> or =150 W) was achieved (p<0.05, odds ratio 2.1). CONCLUSION: The myocardial perfusion defects were registered in 63.1% of patients with suspected coronary artery disease, abnormal resting electrocardiogram, and noninterpretable exercise test. The probability of reversible perfusion defects was higher in male patients, in patients with pre-existing left bundle-branch block and with sufficient working capacity (> or =150 W).

Prediction of decrease in myocardial perfusion defect size and severity during a 3-month follow-up by the degree of acute resolution of electrocardiographic changes.

Myocardial perfusion in infarct-related artery (IRA) distribution improves progressively until a few months after successful reperfusion therapy. We assessed the rate of electrocardiographic (ECG) stage dynamics to predict perfusion improvement after mechanical, thrombolytic, or spontaneous recanalization of IRA. Thirteen patients were divided into group A (n = 8, with > or = 2 ECG stages per 2-day change rate) and group B (n = 5, no rapid change of ECG stages). There were no significant technetium Tc 99m sestamibi scintigraphic differences between the groups 3 days after recanalization; however, after 3 months, perfusion deficit size (2.8 +/- 1.8 vs 4.8 +/- 1.2, P < or = .03) and severity (1.8 +/- 0.9 vs 3.0 +/- 0, P < or = .03) were smaller in group A vs group B. The prediction sensitivity of the method was 87.5% for decrease in size and 100% for decrease in severity of perfusion defect; the specificity was 80% and 100%, respectively. A change rate of 2 or more ECG stages per 2 days predicts follow-up improvement of myocardial perfusion after IRA recanalization.

[When can normal stress myocardial perfusion scans be observed in patients with chest pain and known or suspected coronary artery disease?]. / Kada galima tiketis normalios kruvio miokardo perfuzijos pacientams, jauciantiems skausmus krutineje, kuriems itariama arba diagnozuota isemine sirdies liga.

UNLABELLED: The aim of this study was to establish characteristic clinical data in patients with normal stress myocardial perfusion scans. MATERIAL AND METHODS: 99mMIBI scintigraphy was performed following a one-day protocol (stress-rest) in 806 patients (out of them 451 men) with suspected or known coronary artery disease. A bicycle exercise test response was estimated as pathological, non-pathological, borderline and non-informative. Myocardial perfusion was scored according to the size and severity of defect. RESULTS: Myocardial perfusion was normal in 287 (35.6%) patients. Univariate analysis showed, that normal stress myocardial perfusion scans more often were established in women than in men (p=0.00001, odds ratio 8.55), in patients with atypical anginal or non-anginal chest pain than with typical angina (p=0.0001, odds ratio 1.92), in patients without previous myocardial infarction (p=0.0001, odds ratio 3.28) and without myocardial revascularization (p=0.0001, odds ratio 3.28). The characteristic bicycle exercise test data for normal scans were non-pathological response vs pathological (p=0.00001, odds ratio 3.03) and reason of discontinuance - target heart rate achieved (85% of maximum) vs ischemic changes (p=0.0005, odds ratio 2.37). CONCLUSIONS: Normal stress myocardial perfusion scans were more often present in women, in patients with atypical angina or non-anginal chest pain, in patients without myocardial infarction and without myocardial revascularization. Achieved target heart rate and non-pathological response to exercise test were commonly observed in patients with normal perfusion scans.

[Prediction and evaluation of surgical treatment results of severe ischemic heart disease]. / Uzleistos isemines sirdies ligos chirurginio gydymo rezultatu prognozavimas bei vertinimas.

OBJECTIVES: To estimate myocardial perfusion in patients with severe coronary artery disease performing before and early after single-photon emission computed tomography coronary artery bypass grafting; to predict results of complete myocardial revascularisation by preoperative perfusion data. MATERIAL AND METHODS: Ten patients with stable coronary artery disease and resting left ventricular wall motion abnormalities (mean ejection fraction 31.8+/-6.4%, mean wall motion index 2.09+/-0.25) underwent (99m)Tc-MIBI single-photon emission computed tomography at rest and after nitrate administration before coronary artery bypass grafting and stress-rest single-photon emission computed tomography early (3 and 6 months) after surgery. We estimated myocardial perfusion, postoperative recovery and calculated scintigraphic indices. RESULTS: The mean number of distal anastomoses was 3.0+/-0.7 and all of the patients had complete myocardial revascularisation. Out of 84 revascularized segments with different degree of myocardial perfusion disorders, 49 (58.3%) segments improved after 3 months and 53 (63.1%) improved after 6 months postoperatively. Amount of segments with fixed perfusion defects increased from 60 preoperatively to 72 after 3 months and 67 after 6 months. Postoperative myocardial perfusion recovery was incomplete following 3 months, but after 6 months it nearly reached ultimate level. Postoperative index of myocardial perfusion recovery was found better than predicted preoperatively. CONCLUSIONS: Estimation of myocardial perfusion changes with single-photon emission computed tomography during early postoperative period, particularly after 6 months, confirms excellent and final results of complete surgical myocardial revascularization. Preoperative single-photon emission computed tomography after nitrate administration provides more information in prediction of postoperative results of complete myocardial revascularization. Estimation of function of fixed perfusion defects can help to predict correct results and to identify hibernating myocardium.

[The diagnostic value of myocardial perfusion in diagnosis of ischemic cardiomyopathy and hypertensive heart disease]. / Miokardo perfuzijos tyrimo svarba diagnozuojant isemine ir hipertenzine kardiomiopatijas.

UNLABELLED: Objective of this study was to detect regional myocardial perfusion defects performing (99m)Tc-MIBI myocardial perfusion imaging and to compare the results with echocardiography for differential diagnostics of the ischemic and hypertensive cardiomyopathy until coronary angiography will be performed. MATERIAL AND METHODS: In total 50 patients with cardiomegaly have been evaluated: 18 patients with hypertensive cardiomyopathy (I(st) group), 15 - with ischemic and hypertensive cardiomyopathy (II(nd) group) and 17 patients with ischemic cardiomyopathy (III(rd) group). All patients underwent 2D echocardiography examination and (99m)Tc-MIBI myocardial perfusion imaging before coronary angiography was done. RESULTS: Thickness of interventricular septum, myocardial mass and relative wall thickness were statistically significantly smaller in the III(rd) group of patients in comparison with the I(st) and the II(nd) group of patients. CONCLUSIONS: Logistic regression model including selected data from myocardial perfusion imaging with (99m)Tc-MIBI in combination with selected echocardiography data enables prognosis of coronary arteries stenosis with 91.2% sensitivity and 93.8% specificity.

[Estimation of myocardial perfusion changes after surgical revasculization with single-photon emission computed tomography]. / Miokardo perfuzijos pokyciu ivertinimas po chirurgines revaskulizacijos sirdies radionuklidines kompiuterines tomografijos metodu.

OBJECTIVE: to estimate myocardial perfusion performing single-photon emission computed tomography before and in early period after coronary artery bypass grafting; to predict results of complete myocardial revascularisation by preoperative perfusion data. MATERIAL AND METHODS: Ten patients with stable coronary artery disease and resting left ventricular wall motion abnormalities (mean ejection fraction 37.7+/-6.5%, mean wall motion index 1.89+/-0.32) underwent 99mTc-MIBI myocardial perfusion single-photon emission computed tomography before and in early period (3 and 6 months) after coronary artery bypass grafting. We estimated myocardial perfusion, postoperative recovery and calculated scintigraphic indices. RESULTS: The mean number of distal anastomoses was 3.5+/-0.9 and all of patients had complete myocardial revascularization. Postoperatively 39 (66.1%) after 3 months and 45 (76.3%) after 6 months of 59 revasculared segments with different degree of myocardial perfusion disorders improved. Postoperative (after 6 months) index of myocardial perfusion recovery was found more than 2 times better than predicted preoperatively, because there was no estimation of hibernating myocardium preoperatively. CONCLUSIONS: Estimation of myocardial perfusion changes with single-photon emission computed tomography in early postoperative period, especially after 6 months, confirms the excellent and final results of complete surgical myocardial revascularization. Present protocol of myocardial perfusion investigation gives incomplete information in prediction of postoperative results of complete myocardial revascularization. Myocardial perfusion study performed after nitrate administration is the method of choice to predict correct results.