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J Czernin

Publications and source records attributed to J Czernin.

At least 19 recordsLinked to original sources
PubMed2002

Clinical applications of FDG-PET in oncology.

Positron emission tomography together with F-18-deoxyglucose (FDG) has emerged as a valuable clinical tool in the field of oncology. FDG-PET diagnoses, stages and restages most cancers with a high diagnostic accuracy. The effects of chemotherapy on tumour metabolism can be monitored with this whole-body technique. Recent studies have established a high prognostic accuracy of PET for predicting the clinical outcome of cancer patients. The current review addresses the role of FDG-PET for diagnosing, staging and restaging of lung cancer, colorectal cancer, lymphoma, melanoma and breast cancer staging and provides a brief outlook for future applications of clinical PET imaging.

Fluorodeoxyglucose F18↗
PubMed2002

The usefulness of F-18 deoxyglucose whole-body positron emission tomography (PET) for re-staging of renal cell cancer.

PURPOSE: The use of whole-body PET for re-staging of renal cell carcinoma has not been investigated. The aim of the current study was to examine the diagnostic accuracy and clinical usefulness of whole-body PET imaging for re-staging of renal cell cancer. PATIENTS AND METHODS: Clinical PET was performed for re-staging in 36 patients with advanced renal cell cancer. Written reports of imaging studies (including CT, MRI, US, plain film and bone scan), patient history, and extensive chart notes were used to define the clinical stage before PET (pre-PET stage). The written PET report was used to define the clinical stage after PET (PET stage). Reports were used to determine the accuracy of PET for re-staging renal cell cancer and for defining biopsy proven lesions. Clinical parameters and biopsy proven lesions served as reference for the accuracy of PET for re-staging renal cell cancer. RESULTS: PET classified the clinical stage correctly in 32/36 patients (89%) and was incorrect in 4/36 (11%) (sensitivity and specificity: 87% and 100%). In 20 patients, 25 suspicious lesions were biopsied within 3.2 +/- 6.7 months of the PET study. Of these, 17 were malignant and 8 were benign. PET correctly classified 21/25 (84%) of the biopsied lesions (sensitivity and specificity: 88% and 75%). CONCLUSION: PET re-stages renal cell cancer with a diagnostic accuracy of 89%. Its diagnostic accuracy for classifying biopsy proven anatomic lesions as malignant or benign was 84%. These findings suggest that PET is useful in characterizing anatomic lesions of unknown significance in patients with renal cell cancer.

Adult↗
PubMed2001

Positron emission tomography in evaluation of dementia: Regional brain metabolism and long-term outcome.

CONTEXT: Deficits in cerebral glucose utilization have been identified in patients with cognitive dysfunction attributed to various disease processes, but their prognostic and diagnostic value remains to be defined. OBJECTIVE: To assess the sensitivity and specificity with which cerebral metabolic patterns at a single point in time forecast subsequent documentation of progressive dementia. DESIGN, SETTING, AND PATIENTS: Positron emission tomography (PET) studies of [(18)F]fluorodeoxyglucose in 146 patients undergoing evaluation for dementia with at least 2 years' follow-up for disease progression at the University of California, Los Angeles, from 1991 to 2000, and PET studies in 138 patients undergoing evaluation for dementia at an international consortium of facilities, with histopathological diagnoses an average of 2.9 years later, conducted from 1984 to 2000. MAIN OUTCOME MEASURES: Regional distribution of [(18)F]fluorodeoxyglucose in each patient, classified by criteria established a priori as positive or negative for presence of a progressive neurodegenerative disease in general and of Alzheimer disease (AD) specifically, compared with results of longitudinal or neuropathologic analyses. RESULTS: Progressive dementia was detected by PET with a sensitivity of 93% (191/206) and a specificity of 76% (59/78). Among patients with neuropathologically based diagnoses, PET identified patients with AD and patients with any neurodegenerative disease with a sensitivity of 94% and specificities of 73% and 78%, respectively. The negative likelihood ratio of experiencing a progressive vs nonprogressive course over the several years following a single negative brain PET scan was 0.10 (95% confidence interval, 0.06-0.16), and the initial pattern of cerebral metabolism was significantly associated with the subsequent course of progression overall (P<.001). CONCLUSION: In patients presenting with cognitive symptoms of dementia, regional brain metabolism was a sensitive indicator of AD and of neurodegenerative disease in general. A negative PET scan indicated that pathologic progression of cognitive impairment during the mean 3-year follow-up was unlikely to occur.

Aged↗
PubMed2001

Impact of 18F-FDG PET on managing patients with colorectal cancer: the referring physician's perspective.

UNLABELLED: Whole-body PET imaging with 18F-FDG has been used successfully to stage colorectal cancer. However, the impact of FDG PET on patient management from the referring physician's point of view has not been determined. METHODS: A questionnaire was sent to referring physicians to determine whether and how PET altered the management of colorectal cancer patients. Management changes, when present, were classified as intermodality (e.g., medical to surgical, surgical to radiation, medical to no treatment) or intramodality (e.g., altered medical, surgical, or radiotherapy approach). RESULTS: Of 60 responses from referring physicians, changes in clinical stage were reported for 25 patients (42%). Among these, the disease was upstaged in 20 patients (80%) and downstaged in 5 patients (20%). The PET findings contributed to intermodality management changes in 22 of the 60 patients (37%), intramodality changes in 11 patients (18%), a combination of management changes in 4 patients (7%), and no change in 19 patients (32%). Two of the 60 patients (3%) had other changes, and no response to this question was received for the remaining 2 patients (3%). As a result of PET findings, physicians avoided major surgery in 41% of patients for whom surgery was the intended treatment. CONCLUSION: This survey-based study of referring physicians shows that FDG PET had a major impact on the management of colorectal cancer patients and contributed to changes in clinical stage and major management decisions in >40% of patients.

Adult↗
PubMed2001

Effect of whole-body (18)F-FDG PET imaging on clinical staging and management of patients with malignant lymphoma.

UNLABELLED: Correct staging is important in selecting the appropriate treatment for lymphoma patients. PET imaging with (18)F-FDG is useful for staging of lymphoma as well as for monitoring of therapy. However, to our knowledge, the clinical impact of PET on staging and management of lymphoma patients has not been reported. METHODS: Standardized questionnaires were mailed to referring physicians asking them whether and how the results of PET imaging had influenced clinical staging and management of the disease in their patients. Management changes, when present, were classified as intermodality (e.g., medical to surgical, surgical to radiation, medical to no treatment) or intramodality (e.g., altered medical, surgical, or radiotherapy approach). RESULTS: The referring physicians returned 52 of 108 questionnaires (48.1%). Physicians indicated that PET led to a change in the clinical stage in 44% of patients: 21% were upstaged and 23% were downstaged. Findings of the PET examination resulted in intermodality changes in management in 42% of patients, in intramodality changes in 10%, and in a combination of the management changes in 10%. Other, not further specified, treatment changes were reported in 6% of patients. PET did not result in any management changes in only 32% of patients. CONCLUSION: This survey-based study of referring physicians indicates that FDG PET has a major impact on the management of lymphoma patients, contributing to changes in clinical stage in 44% and changes in treatment in >60% of cases.

Adolescent↗
PubMed2001

Impact of whole-body 18F-FDG PET on staging and managing patients with breast cancer: the referring physician's perspective.

UNLABELLED: FDG PET has emerged as an important clinical imaging modality for diagnosing and staging cancer. However, the impact of FDG PET on staging and managing patients with breast cancer from the referring physician's point of view is unknown. METHODS: The referring physicians of 160 breast cancer patients received standardized questionnaires inquiring if and how PET findings altered their patient's stage and their clinical management decisions. Management changes were classified as intermodality if the change was from one modality to another (e.g., medical to surgical, surgical to radiation, medical to no treatment, and vice versa) or as intramodality if the change was within the same modality (e.g., altered medical or radiotherapy approach). RESULTS: Fifty of the 160 surveys were completed (31% response rate). PET changed the clinical stage in 36% of patients (28% upstaged, 8% downstaged) and resulted in intermodality changes in 28% of patients and intramodality changes in 30% of patients. CONCLUSION: The results of this prospective survey show that FDG PET has a major impact on the management of breast cancer patients, influencing both clinical stage and management in more than 30% of patients.

Adult↗
PubMed2000

Regulation of myocardial blood flow response to mental stress in healthy individuals.

Mental stress testing has been proposed as a noninvasive tool to evaluate endothelium-dependent coronary vasomotion. In patients with coronary artery disease, mental stress can induce myocardial ischemia. However, even the determinants of the physiological myocardial blood flow (MBF) response to mental stress are poorly understood. Twenty-four individuals (12 males/12 females, mean age 49 +/- 13 yr, range 31-74 yr) with a low likelihood for coronary artery disease were studied. Serum catecholamines, cardiac work, and MBF (measured quantitatively with N-13 ammonia and positron emission tomography) were assessed. During mental stress (arithmetic calculation) MBF increased significantly from 0.70 +/- 0.14 to 0.92 +/- 0.21 ml x min(-1) x g(-1) (P < 0.01). Mental stress caused significant increases (P < 0.01) in serum epinephrine (26 +/- 16 vs. 42 +/- 17 pg/ml), norepinephrine (272 +/- 139 vs. 322 +/- 136 pg/ml), and cardiac work [rate-pressure product (RPP) 8,011 +/- 1,884 vs. 10,416 +/- 2,711]. Stress-induced changes in cardiac work were correlated with changes in MBF (r = 0.72; P < 0.01). Multiple-regression analysis revealed stress-induced changes in the RPP as the only significant (P = 0.0001) predictor for the magnitude of mental stress-induced increases in MBF in healthy individuals. Data from this group of healthy individuals should prove useful to investigate coronary vasomotion in individuals at risk for or with documented coronary artery disease.

Adult↗
PubMed2000

Altered regulation of the myocardial microcirculation in young smokers.

Smoking is known to affect microcirculatory function in a middle-aged population. However, the effects of smoking on myocardial perfusion in young smokers have not been studied. Myocardial perfusion was measured in 15 smokers (24 +/- 2 years) and 15 nonsmokers (24 +/- 3 years) using positron emission tomography. Myocardial perfusion was measured at rest, during cold stress and during dipyridamole. Resting myocardial blood flow was similar in the two groups. The well-described correlation between rate-pressure product and myocardial blood flow was present only in the nonsmokers (r(2) = 0.61, p < 0.001). Myocardial blood flow corrected for the rate-pressure product declined during cold by 20% in the smokers [1.11 +/- 0.28 vs. 0.92 +/- 0.20 ml x g(-1) x min(-1) (p = 0.012)], but remained unchanged in nonsmokers [1.11 +/- 0.25 vs. 1.09 +/- 0.30 ml x g(-1) x min(-1) (p = NS)]. Dipyridamole-induced hyperemia was similar in the two groups [2.23 +/- 0.78 vs. 2.42 +/- 0.65 ml x g(-1) x min(-1) (p = NS)]. In conclusion, smoking induces abnormalities in myocardial microcirculatory regulation in young otherwise healthy smokers. The coronary flow reserve, however, is not significantly altered.

Endothelium, Vascular↗
PubMed2000

Effect of mental stress on myocardial blood flow and vasomotion in patients with coronary artery disease.

UNLABELLED: In patients with coronary artery disease (CAD), mental stress may provoke ischemic electrocardiograph changes and abnormalities in regional and global left ventricular function. However, little is known about the underlying myocardial blood flow response (MBF) in these patients. METHODS: We investigated the hemodynamic, neurohumoral, and myocardial blood flow responses to mental stress in 17 patients with CAD and 17 healthy volunteers of similar age. Mental stress was induced by asking individuals to solve mathematic subtractions in a progressively challenging sequence; MBF was quantified at rest and during mental stress using 13N ammonia PET. RESULTS: Mental stress induced significant (P < 0.01) and comparable increases in rate-pressure product, measured in beats per minute x mm Hg, in both patients (from 7826 +/- 2006 to 10586 +/- 2800) and healthy volunteers (from 8227 +/- 1272 to 10618 +/- 2468). Comparable increases also occurred in serum epinephrine (58% in patients versus 52% in healthy volunteers) and norepinephrine (22% in patients versus 27% in healthy volunteers). Although MBF increased in patients (from 0.67 +/- 0.15 to 0.77 +/- 0.18 mL/min/g, P < 0.05) and healthy volunteers (from 0.73 +/- 0.13 to 0.95 +/- 0.22 mL/min/g, P < 0.001), the magnitude of flow increase was smaller in patients (14% +/- 17%) than in healthy volunteers (29% +/- 14%) (P = 0.01). The increase in MBF during mental stress correlated significantly with changes in cardiac work in healthy volunteers (r = 0.77; P < 0.001) but not in patients. CONCLUSION: Despite similar increases in cardiac work and comparable sympathetic stimulation in CAD patients and healthy volunteers, CAD patients exhibit an attenuated blood flow response to mental stress that may contribute to mental stress-induced ischemic episodes in daily life.

Ammonia↗
PubMed2000

A meta-analysis of the literature for whole-body FDG PET detection of recurrent colorectal cancer.

UNLABELLED: A meta-analysis of the literature for the use of FDG PET in the detection of recurrent colorectal cancer (CRC) was conducted to evaluate the quality of the reported studies. Overall values for the sensitivity and specificity of whole-body FDG PET and an overall FDG PET-directed percentage change in management were also determined through this analysis. METHODS: Guidelines to evaluate the articles were formulated on the basis of the U.S. medical payer source criteria for assessing studies that report information on usage of new medical technology. A metaanalysis was conducted using methodology described in the peer-reviewed literature. RESULTS: On the basis of the guidelines established for our review, the availability of necessary information for assessing the reliability of the FDG PET data for diagnosing recurrent CRC was less than ideal. Through a meta-analysis of 11 articles, we determined, within a 95% confidence level, an overall sensitivity of 97% (95% confidence level, 95%-99%) and an overall specificity of 76% (95% confidence level, 64%-88%) for FDG PET detecting recurrent CRC throughout the whole body. Furthermore, through pooling of the change-in-management data, an overall FDG PET-directed change in management was calculated to be 29% (95% confidence level, 25%-34%). CONCLUSION: Our review suggests that improvements can be made to more effectively report the results of these FDG PET studies. The overall values determined through the meta-analysis indicate the potential benefits of using FDG PET as a diagnostic or management tool. Furthermore, these values should prove to be useful to assess the cost-effectiveness of using FDG PET in the management of patients with recurrent CRC.

Colorectal Neoplasms↗
PubMed2000

A review of the literature for whole-body FDG PET in the management of patients with melanoma.

BACKGROUND: A review and meta-analysis of the literature on the use of 2-[18F]fluoro-2-deoxy-D-glucose (FDG) positron emission tomography (PET) in the detection of recurrent melanoma was conducted. The goals were to evaluate the quality of data reporting and to determine the overall values for the sensitivity and specificity of whole body FDG PET and management changes. METHODS: Guidelines to evaluate reporting within articles were formulated based on the United States medical payer source criteria for assessing studies reporting information on the utilization of new medical technology. A meta-analysis was conducted using methodology described in the peer reviewed literature. RESULTS: Our MEDLINE PLUS search resulted in a universe of 89 total articles. Within these 89, 19 were categorized in our targeted content area of which 13 were selected for analysis in our targeted subset, with the remaining 70 covering 24 different related content areas. Five of 13 (38%) articles in the target subset reported data which was adequate for incorporation into modeling objectives based on PET sensitivity and specificity values, with 1 of 13 (8%) in the same target subset reporting data adequate for modeling based on change-in-management data. Through a meta-analysis of the 13 target articles we determined, within a 95% confidence level, an overall sensitivity of 92% (95% confidence level 88.41%-95.82%) and an overall specificity of 90% (95% confidence level 83.26%-96.05%) as calculated by number of lesions, for FDG PET detecting recurrent melanoma throughout the whole body. Furthermore, limited data available for change-in-management suggests an overall FDG PET directed change-in-management value of 22%. CONCLUSIONS: Our review suggests that improvements can be made to more effectively report the results of these FDG PET studies. The overall values determined through the meta-analysis indicate the potential benefits of using FDG PET as a diagnostic/management tool. Furthermore, these values should prove useful to assessing the cost effectiveness of utilizing FDG PET in the management of recurrent melanoma.

Confidence Intervals↗
PubMed1999

Prevalence of myocardial viability as detected by positron emission tomography in patients with ischemic cardiomyopathy.

BACKGROUND: Detection of myocardial viability is important in patients with ischemic cardiomyopathy. Restoration of blood flow to viable myocardium is associated with improved left ventricular function and improved patient prognosis. However, the prevalence of viable myocardium in patients with ischemic cardiomyopathy is unknown. METHODS AND RESULTS: To determine the prevalence of myocardial viability, clinical [13N]ammonia/18F-deoxyglucose PET studies performed in 283 patients (age, 63+/-10 years) with ischemic heart disease (mean ejection fraction, 26+/-8%) were visually analyzed for the presence and extent of viable and nonviable myocardium. The myocardium was divided into 19 segments. The extent of viable myocardium was considered "functionally" significant if >/=5 segments ( approximately 25% of the left ventricular myocardium) exhibited a blood flow/metabolism mismatch and "prognostically" significant if 1 to 4 left ventricular segments did so. Of all patients, 41% had no evidence of viable myocardium, 55% had viable myocardium, and 4% had normal blood flow and metabolism within an enlarged left ventricle. Functionally significant viability was found in 27% and prognostically significant viability in 28% of the patients. Multivariate analysis revealed the presence of angina to be the only clinical parameter associated with the presence of functionally significant viability. CONCLUSIONS: Revascularization might improve patient prognosis in 55% and result in improved left ventricular function in 27% of all patients with ischemic cardiomyopathy.

Aged↗
PubMed1999

Endothelium-dependent and -independent perfusion reserve and the effect of L-arginine on myocardial perfusion in patients with syndrome X.

BACKGROUND: Impaired vasodilatation capacity in patients with angina pectoris and a normal coronary arteriogram (syndrome X [SX]) has been reported. Most studies report on the response in epicardial vessels. This does not necessarily reflect compromised myocardial microcirculation. Lack of the NO precursor L-arginine has been suggested as a possible cause. METHODS AND RESULTS: Myocardial blood flow (MBF) was measured, using PET, at rest (MBF-rest) and during intravenous dipyridamole (MBF-DIP) in 25 women (mean age 53+/-7 years) with SX. Thirty healthy volunteers served as controls. One group (A) consisted of 15 age-matched female volunteers (54+/-10 years). The other control group consisted of 15 young healthy women (B; 24+/-5 years). In 12 SX patients, MBF-rest and MBF during cold pressor testing were also measured after infusion of L-arginine (6.7 g/min for 45 minutes). The increase in MBF after cold pressor testing was similar in the SX group compared with controls. L-arginine did not affect MBF-rest (0.83+/-0.14 versus 0.89+/-0.13 mL. g-1. min-1) or MBF after cold pressor test (0.95+/-0.10 versus 1. 03+/-0.17 mL. g-1min-1). In contrast, the hyperemic response to DIP was blunted compared with the group A controls (1.68+/-0.49 versus 2. 34+/-0.45 mL. g-1. min-1, P<0.05); this resulted in a significant reduction of the coronary flow reserve in SX patients relative to controls (2.03+/-0.53 versus 2.96+/-0.63 mL. g-1. min-1, P<0.01). CONCLUSIONS: In patients with SX, the microcirculatory response to cold, reflecting the endothelium function, is normal and unaltered by intravenous L-arginine. This suggests preserved microcirculatory endothelial function. However, a markedly attenuated hyperemic flow and flow reserve after DIP suggest a dysfunction of the adenosine-mediated endothelium-independent vasodilatation at the microcirculatory level in these patients.

Arginine↗
PubMed1999

L-Arginine normalizes coronary vasomotion in long-term smokers.

BACKGROUND: Noninvasive measurements of myocardial blood flow (MBF) with PET revealed an abnormal coronary vasomotor response to cold pressor test in healthy long-term smokers. If coronary endothelial dysfunction accounted for this abnormality, we hypothesized that it could be reversed by L-arginine as the substrate for NO synthase. METHODS AND RESULTS: MBF was quantified with 13N-labeled ammonia and PET in 11 healthy smokers (age, 45+/-10 years; 27+/-10 years of smoking) and in 12 age-matched nonsmokers on 2 separate days. On day 1, MBF was measured at rest and, after intravenous L-arginine, during cold pressor test. On day 2, MBF was measured during cold pressor test and then at rest during L-arginine. Baseline rate-pressure product (RPP) (6559+/-1590 versus 7144+/-1157 bpmxmm Hg) and MBF (0.65+/-0.14 versus 0.73+/-0.13 mL x g-1 x min-1) were similar in nonsmokers and smokers. Cold pressor test increased RPP similarly in both groups (53+/-26% versus 46+/-26%), whereas MBF increased in nonsmokers (to 0.93+/-0.25 mL x g-1 x min-1; P<0.05) but not in smokers (0.80+/-0.16 mL x g-1 x min-1). The percent MBF increase differed between nonsmokers and smokers (44+/-25% versus 11+/-14%; P=0.0017). However, after L-arginine, the magnitude of MBF response to cold pressor test no longer differed between groups (48+/-36% versus 48+/-28%), whereas RPP again increased similarly in the 2 groups (59+/-30% versus 44+/-16%). L-Arginine had no effect on resting MBF in smokers or nonsmokers. CONCLUSIONS: Our findings implicate the coronary endothelium as the major site of the abnormal vasomotor response in long-term smokers. Cold pressor test combined with PET imaging may allow the noninvasive identification of coronary endothelial dysfunction in humans.

Adult↗
PubMed1999

Noninvasive determination of myocardial blood flow, oxygen consumption and efficiency in normal humans by carbon-11 acetate positron emission tomography imaging.

The aims of this study were: (1) to measure noninvasively and near simultaneously myocardial blood flow, oxygen consumption, and contractile function and (2) to analyze myocardial energy expenditure and efficiency at rest and during dobutamine stress in normal humans. Dynamic and gated carbon-11 acetate positron emission tomography (PET) imaging was performed in 11 normal subjects. The initial uptake of (11)C-acetate was measured to estimate myocardial blood flow. Oxygen consumption was derived from the monoexponential slope of the (11)C-clearance curve recorded during myocardial washout. ECG-gated systolic and diastolic images were acquired during the peak myocardial (11)C activity to measure left ventricular radius, myocardial wall thickness, and long axis length. Myocardial oxygen consumption and parameters of cardiac geometry were used to determine myocardial energetics and cardiac efficiency by tension-area area analysis. Myocardial blood flow averaged 0. 8+/-0.06 ml min(-1) g(-1) at rest and 1.48+/-0.15 ml min(-1) g(-1) during dobutamine stress. Oxygen delivery and consumption were 151+/-13 and 88+/-15 microl O(2) min(-1) g(-1) at rest and increased to 291+/-31 and 216+/-31 microl O(2) min(-1) g(-1), respectively, during pharmacological stress (P<0.001). Oxygen extraction increased from 59%+/-8% at rest to 76%+/-9% during stress (P<0.001). Mechanical efficiency was 29%+/-6% at rest and 32%+/-6% during dobutamine stress (P=NS) while external work efficiency was 16%+/-6% at rest and increased to 21%+/-4% (P<0.01) during dobutamine stress. Stepwise linear regression analysis identified rate-pressure product and external cardiac work as major correlates of oxygen consumption. In summary, rapid dynamic and gated PET (11)C acetate imaging provides the unique capability to study noninvasively determinants of myocardial energy delivery, expenditure, and efficiency.

Acetates↗
PubMed1999

Blood flow-metabolism imaging with positron emission tomography in patients with diabetes mellitus for the assessment of reversible left ventricular contractile dysfunction.

OBJECTIVES: The purpose of this study was to evaluate the predictive accuracy of positron emission tomography (PET) blood flow-F-18 fluorodeoxyglucose (FDG) imaging in coronary artery disease (CAD) patients with diabetes mellitus (DM). BACKGROUND: Positron emission tomography accurately predicts the postrevascularization improvement in left ventricular dysfunction in unselected patients with CAD. In diabetic patients, however, poor myocardial glucose utilization may limit the accuracy of the approach. METHODS: Forty patients (64+/-10 years old; 19 with DM = group I; 21 without DM = group II) with reduced left ventricular ejection fraction (LVEF = 29+/-6%) were studied with N-13 ammonia and FDG PET before coronary revascularization. Studies were performed after intravenous injection of regular insulin (group I) or oral glucose administration (group II). Blood flow-FDG mismatches and matches were identified by polar map analysis in the three vascular territories of the left anterior descending, left circumflex and right coronary artery. Wall motion and LVEF were assessed by two-dimensional echocardiography before and 158+/-123 days after revascularization. RESULTS: Of 107 vascular territories analyzed, 46 were classified as mismatch, 29 as match and 32 as normal. The FDG image quality, assessed by F-18 myocardium to blood pool activity ratios, and the predictive accuracy were similar in both groups; presence of a blood flow/FDG mismatch had a sensitivity of 92% (group I) and 94% (group II) and a specificity of 85% (group I) and 79% (group II) for an improvement in regional left ventricular function. A postrevascularization improvement in global left ventricular function was related to the extent of blood flow/FDG mismatch; LVEF increased from 30+/-7% to 35+/-7% (p = 0.017) in patients with one mismatch and from 27+/-4% to 41+/-7% (p < 0.001) in those with two mismatches. CONCLUSIONS: The predictive accuracy of blood flow/FDG imaging is maintained in patients with DM when a clinically acceptable study protocol, which guarantees good FDG image quality, is used. The extent of a blood flow/metabolism mismatch is correlated with the magnitude of the postrevascularization improvement in global left ventricular function.

Aged↗
PubMed1999

Relationship between coronary function by positron emission tomography and temporal changes in morphology by intravascular ultrasound (IVUS) in transplant recipients.

BACKGROUND: Transplant coronary vasculopathy is one of the major causes of graft failure and death in cardiac transplant recipients. A non-invasive test of coronary function to predict the course of this disease would be desirable. METHODS: To determine whether the degree of abnormalities in endothelial dependent coronary vasomotion (cold pressor testing) or endothelial independent vasodilatory capacity (intravenous dipyridamole) as determined by positron emission tomography (PET) one to two years after heart transplantation is correlated with the course of transplant vasculopathy. Nineteen patients had baseline PET and intravascular ultrasound studies (IVUS) at 18 +/- 6 months after cardiac transplantation and a follow up IVUS study 15 +/- 5 months later. RESULTS: Myocardial blood flow was higher in patients than in healthy controls (p < 0.002) but increased during cold pressor testing only in controls (p < 0.005). Myocardial blood flow normalized to the rate pressure product declined in patients (p < 0.001). Dipyridamole-induced hyperemic blood flow and the flow reserve normalized to the resting rate pressure product were lower in patients than in controls (p < 0.001 and p < 0.01). The normalized flow reserve was correlated with changes in total vessel area (r = 0.55; p = 0.02) and lumen diameter (r = 0.52; p < 0.05). CONCLUSION: These findings suggest that the degree of abnormalities in endothelial independent myocardial flow as detected by PET one to two years after transplantation is associated with morphological indices of disease progression by IVUS.

Cold Temperature↗