Simultaneous dobutamine stress echocardiography and technetium-99m isonitrile single-photon emission computed tomography in patients with suspected coronary artery disease.

OBJECTIVES: The purpose of this study was to determine the relative value of dobutamine stress echocardiography and technetium-99m isonitrile single-photon emission computed tomography (mibi SPECT) in the detection of myocardial ischemia. BACKGROUND: Stress-induced new wall motion abnormalities and transient perfusion defects are both used for the diagnosis of myocardial ischemia. METHODS: One hundred five consecutive patients with either proved or suspected coronary artery disease, who were referred for perfusion scintigraphy, were studied by a combination of the two techniques. Both echocardiographic and mibi SPECT images were visually analyzed. Three patients were excluded from the final analysis because of unsatisfactory examinations: two with noninterpretable stress echocardiograms and one with noninterpretable mibi SPECT images. The response to stress was concordantly classified by both techniques in 68% of patients (kappa = 0.51). RESULTS: Dobutamine stress echocardiography revealed the presence of ischemia in 38 and mibi SPECT in 45 patients (overall agreement = 74%, kappa = 0.46). The agreement was higher in patients without previous myocardial infarction (84%, kappa = 0.62). When regional analysis was performed, concordance of stress echocardiography and mibi SPECT occurred in 84% of the 306 regions (kappa = 0.45). Regional agreement was also slightly higher in patients without previous infarction (88%, kappa = 0.50). In 21 patients without previous myocardial infarction who underwent coronary angiography, the overall sensitivity of dobutamine stress echocardiography and mibi SPECT for the diagnosis of coronary artery disease (diameter stenosis > 50%) was 75% and 83%, respectively, with a specificity of 89% (eight of nine patients) for both tests. CONCLUSIONS: Dobutamine stress echocardiography represents a reasonable alternative to dobutamine mibi SPECT for the functional assessment of patients with suspected myocardial ischemia and without previous myocardial infarction.

Quantitative angiographic measurements of isolated left anterior descending coronary artery stenosis. Correlation with exercise echocardiography and technetium-99m 2-methoxy isobutyl isonitrile single-photon emission computed tomography.

OBJECTIVES: This study sought to assess the value of quantitative coronary arteriography in predicting an ischemic response at exercise echocardiography and technetium-99m 2-methoxy isobutyl isonitrile (mibi) single-photon emission computed tomography (SPECT) in patients with single-vessel disease of the left anterior descending coronary artery. BACKGROUND: The relation between severity of coronary stenosis and ischemic response to exercise echocardiography and perfusion scintigraphy in patients with single-vessel left anterior descending coronary artery disease is not well established. METHODS: Thirty-one patients without a previous myocardial infarction who had isolated stenosis of varying degrees in the proximal or midportion of the left anterior descending coronary artery were studied. Quantitative arteriographic analysis was used for measurements of percent diameter stenosis and minimal lumen diameter. Exercise-induced wall motion abnormalities by echocardiography and transient perfusion defects by mibi SPECT were considered a positive response. The analysis of sensitivity/specificity and receiver operating characteristic curves was applied to establish the diagnostic power of quantitative coronary arteriography to predict an ischemic response to exercise echocardiography and mibi SPECT: RESULTS: The "best" angiographic cutoff values for predicting a positive exercise echocardiographic and scintigraphic response were similar (diameter stenosis 52%, minimal lumen diameter 1.12 mm for echocardiography; diameter stenosis 49%, minimal lumen diameter 1.20 mm for SPECT). However, the sensitivity/specificity at the cross point was slightly higher (even if not statistically significant) for echocardiography than for SPECT, both for diameter stenosis (81% vs. 67%) and minimal lumen diameter (81% vs. 74%), suggesting that quantitative coronary arteriographic measurements are more closely related to echocardiographic than scintigraphic exercise test results. CONCLUSIONS: The functional significance of a proximal/mid-left anterior descending coronary artery stenosis measured by quantitative coronary arteriography is slightly better related to echocardiographic than scintigraphic markers of exercise-induced myocardial ischemia.

Prediction of recovery of myocardial dysfunction after revascularization. Comparison of fluorine-18 fluorodeoxyglucose/thallium-201 SPECT, thallium-201 stress-reinjection SPECT and dobutamine echocardiography.

OBJECTIVES: We compared three techniques to predict functional recovery after revascularization. BACKGROUND: Recently, fluorine-18 (F-18) fluorodeoxyglucose in combination with single-photon emission computed tomography (SPECT) has been proposed to identify viable myocardium, Thallium-201 reinjection and low dose dobutamine echocardiography are used routinely for this purpose. METHODS: Seventeen patients (mean [+/- SD] left ventricular ejection fraction 36 +/- 11%) were studied. Regional and global ventricular function were evaluated before and 3 months after revascularization by echocardiography and radionuclide ventriculography, respectively. Myocardial F-18 fluorodeoxyglucose uptake (during hyperinsulinemic glucose clamping) was compared with rest perfusion assessed with early thallium-201 SPECT. On a separate day, low dose dobutamine echocardiography and post-stress thallium-201 reinjection SPECT were simultaneously performed. RESULTS: The sensitivities for F-18 fluorodeoxyglucose/thallium-201, thallium-201 reinjection and low dose dobutamine echocardiography to assess recovery were 89%, 93% and 85%, respectively; specificities were 77%, 43% and 63%, respectively. Stepwise logistic regression indicated that F-18 fluorodeoxyglucose/ thallium-201 was the best predictor. In hypokinetic segments, the combination of F-18 fluorodeoxyglucose/thallium-201 and low dose dobutamine echocardiography was the best predictor. Global function improved (left ventricular ejection fraction increased > 5%) in 6 patients and remained unchanged in 11. All three techniques correctly identified five of six patients with improvement. Fluorine-18 fluorodeoxyglucose/thallium-201 identified all patients without improvement; low dose dobutamine echocardiography identified 9 of 11 without improvement; and thallium-201 reinjection identified 6 of 11 patients without improvement. CONCLUSIONS: Fluorine-18 fluorodeoxyglucose/thallium-201 SPECT was superior to the other techniques in assessing functional recovery. Integration of metabolic and functional data is necessary, particularly in hypokinesia, for optimal prediction of improvement of regional function.

Prognostic value of dobutamine-atropine stress technetium-99m sestamibi perfusion scintigraphy in patients with chest pain.

OBJECTIVES: This study investigated the prognostic value of dobutamine-atropine technetium-99m (Tc-99m) sestamibi single-photon emission computed tomographic (SPECT) myocardial perfusion imaging. BACKGROUND: Dobutamine-atropine Tc-99m sestamibi SPECT imaging is an accurate method for the detection of coronary disease. However, the prognostic value of this stress modality has not been assessed. METHODS: Three hundred ninety-two consecutive patients with chest pain (mean [+/- SD] age 60 +/- 12 years; 220 men, 190 with a previous myocardial infarction) underwent a dobutamine-atropine Tc-99m sestamibi SPECT scintigraphic study. Patients were followed up for 22 +/- 13 months to determine the univariate and multivariate variables associated with hard cardiac events (cardiac death, nonfatal myocardial infarction), to define their event-free survival and to determine whether the extent and severity of reversible perfusion defects correlated with events. RESULTS: Forty-four patients (11%) had hard cardiac events. Multivariate models demonstrated that older age (odds ratio [OR] 2.1, 95% confidence interval [CI] 1.0 to 4.4), history of heart failure (OR 2.6, 95% CI 1.3 to 5.2), abnormal sestamibi scan results (OR 10.0, 95% CI 2.3 to 43.0) and reversible perfusion defects (OR 3.2, 95% CI 1.6 to 6.4) had independent predictive value. Patients without perfusion defects, with fixed defects alone, reversible defects alone and fixed plus reversible defects had annual hard cardiac event rates of 0.8%, 6.8%, 8.1% and 11.6%, respectively. Patients with increasing reversible defect scores had increasing annual event rates of 2.1%, 5.0%, 5.5%, 13.0% and 14.6%, respectively. CONCLUSIONS: Dobutamine-atropine stress Tc-99m sestamibi SPECT imaging provides excellent prognostic information. The single most important independent predictor for future hard cardiac events is an abnormal pattern, and a reversible defect provides additional, independent prognostic information. Moreover, the extent and severity of reversible defects are major determinants for prognosis.

Dobutamine-induced hypoperfusion without transient wall motion abnormalities: less severe ischemia or less severe stress?

OBJECTIVES: This study sought to compare the clinical characteristics, hemodynamic response and severity of ischemia in patients with coronary artery disease and reversible perfusion defects on dobutamine 2-methoxy isobutyl isonitrile (MIBI) single-photon emission computed tomography (SPECT) with or without transient wall motion abnormalities. BACKGROUND: The occurrence of reversible perfusion defects without concomitant wall motion abnormalities in patients with coronary artery disease was attributed to less severe ischemia. However, little data are available to support this observation. METHODS: Fifty-four consecutive patients with significant coronary artery disease and reversible perfusion defects on dobutamine (up to 40 micrograms/kg body weight per min) MIBI SPECT were studied (mean [+/- SD] age 59 +/- 11 years; 38 men, 16 women). All patients underwent simultaneous echocardiography. The myocardium was divided into six matched segments, and ischemic perfusion score was quantitatively derived in myocardial segments with reversible defects. RESULTS: New or worsening wall motion abnormalities occurred in 40 patients (74%) (group A) and were absent in 14 (26%) (group B). There was no significant difference between the two groups with respect to age, previous myocardial infarction, number of abnormal coronary arteries (1.8 +/- 0.8 vs. 1.6 +/- 0.9), number of reversible perfusion defects (1.6 +/- 0.9 vs. 1.8 +/- 0.7) or ischemic perfusion score (412 +/- 750 vs. 526 +/- 553). Patients in group A had a higher prevalence of male gender (80% vs. 43%, p < 0.01), higher peak systolic blood pressure (147 +/- 30 vs. 127 +/- 31 mm Hg, p < 0.05), higher peak rate-pressure product (19,632 +/- 4,081 vs. 16,939 +/- 4,344, p < 0.01) and a higher prevalence of angina (53% vs. 14%) and ST segment depression (55% vs. 14%) than group B (p < 0.05 for both). CONCLUSIONS: In patients with coronary artery disease and ischemia on dobutamine MIBI SPECT, the absence of transient wall motion abnormalities is associated with a similar extent and severity of reversible perfusion defects, a lower stress rate-pressure product and a higher prevalence of female gender than patients with transient wall motion abnormalities. Mechanically silent ischemia should not be regarded as a marker of less severe ischemia on myocardial perfusion scintigraphy.

Dobutamine thallium-201 SPECT imaging for assessment of peri-infarction and remote myocardial ischemia.

UNLABELLED: This study assessed the value of dobutamine 201Tl scintigraphy for detecting significant disease of infarct-related and remote coronary arteries in myocardial infarction patients. METHODS: Dobutamine (up to 40 micrograms/kg/min)/atropine (up to 1 mg) stress test in conjunction with stress-reinjection 200Tl SPECT was performed in 71 symptomatic patients with left ventricular dysfunction > 3 mo after myocardial infarction. Ischemia was defined as reversible perfusion defects. RESULTS: Significant coronary artery stenosis (> or = 50% luminal diameter stenosis) was detected in all patients. Sensitivity, specificity and accuracy of regional ischemia for the diagnosis of remote coronary artery stenosis were 74% (95% Cl 63-86), 80% (Cl 70-90) and 76% (Cl 65-87), respectively. Those for infarct-related artery stenosis were 71% (Cl 60-81), 83% (Cl 75-92) and 72% (Cl 61-82), respectively. Ischemic perfusion score was higher in patients with multiversus single-vessel disease (1056 +/- 1021 versus 423 +/- 633, p < 0.01). CONCLUSION: Dobutamine thallium scintigraphy is valuable for assessing the extent of coronary stenosis on the basis of reversible hypoperfusion in symptomatic patients late after myocardial infarction.

Safety of dobutamine-atropine stress myocardial perfusion scintigraphy.

UNLABELLED: Dobutamine stress testing is increasingly used for the diagnosis and functional evaluation of coronary artery disease. However, the relationship between myocardial perfusion abnormalities and complications of the test has not been studied. METHODS: We studied the hemodynamic profile, safety and feasibility of dobutamine (up to 40 microg/kg/min)-atropine (up to 1 mg) stress myocardial perfusion SPECT imaging (with 201TI, 99mTc-MIBI or tetrofosmin) in a consecutive series of 1076 patients (age = 59 +/- 11 yr, 50% with previous myocardial infarction) referred for evaluation of myocardial ischemia. RESULTS: No infarction or death occurred during the test. The test was considered feasible (achievement of 85% of the target heart rate or an ischemic endpoint) in 1005 patients (94%). Hypotension (systolic blood pressure drop > or = 40 mm Hg) occurred in 37 patients (3.4%). Independent predictors were higher baseline systolic blood pressure (p < 0.0001), number of ischemic segments (p < 0.05) and age (p < 0.05). Supraventricular tachyarrhythmias occurred in 48 patients (4.4%). Independent predictors were fixed perfusion defect (infarction) score (p < 0.005) and age (p < 0.05). Ventricular tachycardia occurred in 41 patients (3.8%). Independent predictors were infarction score (p < 0.01) and male gender (p < 0.05). All arrhythmias terminated spontaneously or after metoprolol administration. CONCLUSION: Dobutamine-atropine myocardial perfusion scintigraphy is a feasible method for the evaluation of coronary artery disease with a safety profile and feasibility comparable to those reported for dobutamine stress echocardiography. Patients with more severe fixed perfusion abnormalities are at a higher risk of developing tachyarrhythmias during the test.

Exercise echocardiography and technetium-99m MIBI single-photon emission computed tomography in the detection of coronary artery disease.

To compare the relative diagnostic value of exercise echocardiography with perfusion technetium-99m metoxyisobutylisonitrile single-photon emission computed tomography (SPECT) in detecting coronary artery disease (CAD), 75 patients with suspected CAD but a normal electrocardiogram (ECG) at rest were included in a prospective correlative study. Both the exercise echocardiograms and SPECT studies were performed in conjunction with the same symptom-limited bicycle exercise test. The development of either a new wall motion abnormality or a reversible perfusion defect after exercise, or both, were regarded as a positive test for the exercise echocardiographic and SPECT studies, respectively. The results of these 2 diagnostic tests were compared with coronary arteriography. Exercise echocardiography identified 35 (71%) and SPECT 41 (84%, p = 0.13) of the 49 patients with significant CAD (defined as greater than 50% diameter stenosis). Twenty-five of the 26 patients (96%) without significant coronary stenosis had negative exercise echocardiographic results and 23 of 26 (88%) had negative SPECT results. Exercise-induced new wall motion abnormalities showed a good correlation with reversible perfusion defects, and the results of the 2 methods were concordant in 65 of 75 patients (agreement = 88%, kappa = 0.75 +/- 0.14). Both the diagnostic accuracy of exercise echocardiography and SPECT were significantly higher than the exercise ECG (81 vs 64%, p less than 0.02 and 88 vs 64%, p less than 0.005). The sensitivity and specificity for detecting individual diseased vessels were 60 and 95% for exercise echocardiography and 67 and 94% for SPECT.(ABSTRACT TRUNCATED AT 250 WORDS)

Prognostic significance of systolic blood pressure changes during dobutamine-atropine stress technetium-99m sestamibi perfusion scintigraphy in patients with chest pain and known or suspected coronary artery disease.

To investigate the prognostic value of dobutamine stress-induced changes in systolic blood pressure (BP) 418 patients (mean age 60 years, 238 men) with chest pain and known or suspected coronary artery disease, who underwent a dobutamine-atropine stress technetium-99m sestamibi myocardial perfusion scintigraphic study, were followed up for 25 +/- 15 months. Blood pressure was measured by automatic sphygmomanometry every 3 minutes. A marked decrease and increase in systolic BP from rest to peak were defined as changes of > or = 20 mm Hg, and > or = 30 mm Hg, respectively. Worst outcome events were cardiac death (n = 30), nonfatal myocardial infarction (n = 17), and hospitalization for congestive heart failure (n = 8). A decrease in systolic BP (prevalence 16%) was associated with older age and higher baseline systolic BP. Fixed and reversible sestamibi perfusion defects and follow-up results were similar to patients without a systolic BP decrease. In contrast, an increase in systolic BP (prevalence 24%) was associated with younger age, lower baseline systolic BP, and with absence of a history of prior congestive heart failure or treatment with angiotensin-converting enzyme inhibitors. Furthermore, these patients had fewer fixed perfusion defects and tended to have fewer annual event rates (3.5% vs 7.5%, p < 0.10). In a multivariate model, an increase in systolic BP was not an independent predictor for subsequent events. In conclusion, a dobutamine-induced decrease in systolic BP is not associated with fixed or reversible sestamibi defects or adverse prognosis. An increase in systolic BP, however, is associated with less fixed sestamibi defects and a tendency toward less annual event rates.

Prognostic significance of normal dobutamine-atropine stress sestamibi scintigraphy in women with chest pain.

To evaluate the prognostic value of normal dobutamine-atropine technetium-99m sestamibi single-photon emission computed tomography (SPECT) perfusion imaging in women with chest pain and inability to perform an adequate exercise test, 80 women with a normal scintigram were followed up for 23 +/- 13 months. Mean age of the patients was 61 +/- 12 years. Nine patients (11%) had a low probability (< 10%) of coronary artery disease, 43 (54%) had an intermediate probability (10% to 80%) of disease, and 28 (35%) had a high probability (>80%) of disease (including 19 patients with known coronary artery disease). During follow-up, no major cardiac events (cardiac death or nonfatal myocardial infarction) occurred. One patient with known coronary disease underwent coronary bypass surgery after 3 months, and 1 patient with a 91% pretest likelihood of coronary disease underwent coronary angioplasty after 7 months. Thus, the overall incidence of (soft) cardiac events during the follow-up period was 2 of 80 patients, or 1.3%/year. It is concluded that normal dobutamine-atropine technetium-99m sestamibi SPECT perfusion imaging in women with chest pain implies an excellent prognosis, even in women with high pretest likelihood of coronary disease.

Evaluation by quantitative 99m-technetium MIBI SPECT and echocardiography of myocardial perfusion and wall motion abnormalities in patients with dobutamine-induced ST-segment elevation.

ST-segment elevation during exercise testing has been attributed to myocardial ischemia and wall motion abnormalities (WMA). However, the functional significance of ST-segment elevation during dobutamine stress testing (DST) has not been evaluated in patients referred for diagnostic evaluation of myocardial ischemia. DST (up to 40 micrograms/kg/min) with simultaneous echocardiography and technetium-99m sestamibi single-photon emission computed tomography (SPECT) was performed in 229 consecutive patients with suspected myocardial ischemia who were unable to perform an adequate exercise test; 127 (55%) had a previous acute myocardial infarction (AMI). ST elevation was defined as > or = 1 mm new or additional J point elevations with a horizontal or upsloping ST segment lasting 80 ms. Reversible perfusion defects on SPECT and new or worsening WMA during stress on echocardiography were considered diagnostic of ischemia. ST elevation occurred in 40 patients (17%) during the test; 34 of them (85%) had previous AMI. All patients with ST-segment elevation had abnormal scintigrams (fixed or reversible defects, or both) and abnormal wall motion (fixed or transient defect, or both) at peak stress. In patients who had ST elevation and no previous AMI (n = 6), ischemia was detected in all by echocardiography and in 5 (83%) by SPECT. In patients with previous AMI, the prevalence of ischemia was not different with or without ST elevation (53% vs 43% by echocardiography and 53% vs 48% by SPECT, respectively). Baseline regional wall motion score in the infarct zone was higher in patients with ST elevation.(ABSTRACT TRUNCATED AT 250 WORDS)

Safety, hemodynamic profile, and feasibility of dobutamine stress technetium myocardial perfusion single-photon emission CT imaging for evaluation of coronary artery disease in the elderly.

OBJECTIVES: Cardiovascular disease is the leading cause of morbidity and mortality in the elderly. The evaluation of coronary artery disease by exercise stress testing is frequently limited by the patient's inability to exercise. Although pharmacologic stress testing with dobutamine is an alternative, the safety of dobutamine myocardial perfusion scintigraphy in the elderly has not been previously studied. PATIENTS AND METHODS: We studied the safety and feasibility of dobutamine (up to 40 microg/kg/min)-atropine (up to 1 mg) stress myocardial perfusion scintigraphy using technetium single-photon emission CT imaging in 227 patients > or = 70 years old (mean +/- SD age, 75 +/- 4 years). A control group of 227 patients < 70 years old (mean age, 55 +/- 11 years; matched for gender, prevalence of previous infarction, beta-blocker therapy, and severity of resting perfusion abnormalities) was studied to assess age-related differences in the safety and the hemodynamic response. A feasible test was defined as the achievement of the target heart rate and/or an ischemic end point (angina, ST-segment depression, or reversible perfusion abnormalities). RESULTS: No myocardial infarction or death occurred during the test. The target heart rate was achieved more frequently in the elderly patients (87% vs 79%; p < 0.05). The elderly patients had a higher prevalence of supraventricular tachycardia (7% vs 1%; p < 0.005) and premature ventricular contraction (74% vs 32%; p < 0.005) during the test, as compared to the younger patients. There was a trend to a higher prevalence of ventricular tachycardia (5% vs 2%) and atrial fibrillation (3% vs 0.4%) in the elderly patients. Arrhythmias were terminated spontaneously by termination of dobutamine infusion or by administration of metoprolol. Independent predictors of supraventricular tachyarrhythmias and ventricular tachycardia were older age (p < 0.001; chi(2), 9.8) and myocardial perfusion defect score at rest (p < 0.01; chi(2), 6.8) respectively, by using a multivariate analysis of clinical and stress test variables. Elderly patients had a higher prevalence of systolic BP drop > 20 mm Hg during the test (37% vs 12%; p < 0.05). The test was terminated due to hypotension in 2% of the elderly patients and in 1% of the control group. Age was the most powerful predictor of hypotension (p < 0.005; chi(2), 10.3). The test was considered feasible in 216 elderly patients (95%) and in 209 patients of the control group (92%). CONCLUSION: Dobutamine-atropine stress myocardial perfusion scintigraphy is a highly feasible method for the evaluation of coronary artery disease in the elderly. Elderly patients have a higher risk for developing hypotension and supraventricular tachyarrhythmias during a dobutamine stress test. However, dobutamine-induced hypotension is often asymptomatic and rarely necessitates the termination of the test.

Prognostic value of dipyridamole sestamibi single-photon emission computed tomography and dipyridamole stress echocardiography for new cardiac events after an uncomplicated myocardial infarction.

A high-dose dipyridamole stress test (0.84 mg/kg in 6 minutes) with simultaneous sestamibi single-photon emission computed tomographic (SPECT) and echocardiographic imaging was performed in 89 patients before hospital discharge after an uncomplicated myocardial infarction. The aim of this study was to determine the prognostic value of these tests for new cardiac events and to compare the relative values of SPECT and echocardiography in a postinfarction dipyridamole stress test. Two years after infarction, nine patients (10%) had died, five patients (6%) had suffered a nonfatal reinfarction, and 14 patients (16%) had been readmitted to the hospital for a revascularization procedure. Cardiac death had occurred in 5 (10%) of 48 patients with a positive SPECT versus 4 (10%) of 41 with a negative SPECT (difference not significant) and in 6 (19%) of 31 with a positive echocardiogram versus 3 (5%) of 56 with a negative echocardiogram (p = 0.05). Cardiac death or reinfarction had occurred in 8 (17%) of 48 patients with a positive SPECT versus 6 (15%) of 41 with a negative SPECT (difference not significant) and in 6 (19%) of 31 with a positive echocardiogram versus 8 (14%) of 56 with a negative echocardiogram (difference not significant). Thus the predictive value of the dipyridamole stress test for new cardiac events after an uncomplicated myocardial infarction was limited, irrespective of the method used to detect ischemia. Reversible perfusion defects were identified more frequently than new wall motion abnormalities but did not predict late events. A positive dipyridamole echocardiogram was associated with a higher late mortality rate but did not predict other cardiac events.

Brain perfusion patterns in familial frontotemporal lobar degeneration.

OBJECTIVE: Frontotemporal lobar degeneration (FTLD) is a clinically, genetically, and pathologically heterogeneous disorder. The aim of this study was to compare clinical features and perfusion patterns on SPECT of patients with familial FTLD-TAR DNA binding protein 43 kDa (TDP) and MAPT mutations. METHODS: Patients were included if they had MAPT or GRN mutations, positive family history with pathologically proven FTLD in the patient or first-degree relative, or were part of FTD-MND families. All patients and 10 age- and gender-matched controls underwent measurement of brain perfusion using (99m)Tc-HMPAO SPECT. We used SPM8 to perform image processing and voxel-based group analyses (p < 0.001). Gender and age were included as nuisance variables in the design matrices. RESULTS: Of the 29 patients with familial FTLD, 19 had familial FTLD-TDP (GRN mutations in 6), and 10 had MAPT mutations. At clinical presentation, familial FTLD-TDP patients were older at onset (p = 0.030) and had more memory deficits (p = 0.011), whereas patients with MAPT had more naming deficits (p < 0.001) and obsessive-compulsive behavior (p = 0.001). The between-groups SPECT analyses revealed significantly less perfusion in the right frontal lobe, precuneus, cuneus, and inferior parietal lobule in familial FTLD-TDP, whereas significantly less perfusion was found in the left temporal and inferior frontal gyri in MAPT. Post hoc analysis of familial FTLD-TDP with unknown genetic defect vs MAPT revealed less perfusion in the right frontal and parietal lobe. CONCLUSION: Familial FTLD-TDP shows relatively more posterior hypoperfusion, including the precuneus and inferior parietal lobule, possibly related to significant memory impairment. Patients with MAPT were characterized by impaired perfusion of the temporal regions and naming deficits.

Relationships between the lung-heart ratio assessed from post-exercise thallium-201 myocardial tomograms, myocardial ischemia and the extent of coronary artery disease.

Uptake of thallium (Tl)-201 in the lungs has been proposed as a measure of left ventricular dysfunction. In this study we were interested in pursuing two goals: 1) to assess possible relationships between the post-exercise Tl-201 lung-heart (LH)-ratio determined from the anterior view during SPECT-acquisition, myocardial ischemia and the extent of coronary artery disease; and 2) to explore the effects of coronary revascularisation procedures on the LH-ratio. The study group consisted of 145 patients with early and late postexercise Tl-201 tomograms, including 32 PTCA-patients with pre- and post-PTCA studies and 20 patients who underwent coronary artery bypass surgery (CABG) with corresponding pre- and post-CABG studies. Ischemia was defined as evoked angina during the exercise test in combination with greater than or equal to 1 mm horizontal or downsloping ST-depression on the ECG. The severity of coronary obstructions was assessed from coronary angiograms with a PC-based digital caliper technique; a stenosis was defined to be significant when its severity exceeded 50% diameter stenosis. The LH-ratio was defined by the ratio of the mean pulmonary counts and the mean myocardial counts assessed from corresponding regions of interest (ROI's) positioned over the left lung and the heart, respectively in the anterior view of a tomographic data acquisition procedure. Our results made clear that the LH-ratio was not significantly different between patients with and without ischemia during exercise, and between patients with single vs. multiple vessel disease.(ABSTRACT TRUNCATED AT 250 WORDS)

Comparative study of three different approaches on the estimation of the lung-heart ratio in thallium 201 scintigrams in relation to the extent of coronary artery disease and left ventricular function.

Uptake of thallium 201 (201Tl) in the lungs has been proposed as a measure of left ventricular dysfunction with exercise. To study this hypothesis, we compared the lung/-heart (LH) ratio assessed from anterior planar images (ANT-P), from anterior images obtained during single photon emission tomography (SPET) acquisition (ANT-T) and from short-axis tomographic cross-sections (CS) in early post-exercise thallium 201 scintigrams. The study population consisted of 54 prepercutaneous transluminal coronary angioplasty (PTCA) studies (82% with single-vessel disease), 50 post-PTCA studies, 33 pre-coronary artery bypass surgery (CABG) studies (71% with three-vessel disease), 30 post-CABG studies and 30 patients with a left ventricular dysfunction (LVD) due to an acute myocardial infarction; 18 individuals with a low likelihood of coronary artery disease (CAD) served as a control group. The results demonstrated that, on average, the LH ratios obtained from ANT-P and ANT-T were not significantly different for all study groups; these ratios increased significantly with ischaemia and with LVD relative to non-ischaemic situations. However, the LH ratios in CS did not show a relation with ischaemia nor with LVD and differed significantly from the LH-ratios assessed from the anterior approaches. Each of the three approaches (ANT-P, ANT-T, CS) was characterized by large overlaps of LH ratios for the different study groups.(ABSTRACT TRUNCATED AT 250 WORDS)

Comparison of exercise echocardiography with myocardial perfusion scintigraphy for the diagnosis of coronary artery disease.

The rationale of exercise echocardiography for the diagnosis of coronary artery disease is based on the detection of exercise-induced wall motion abnormalities by ultrasound. Some of the problems that had previously limited the widespread application of the test have been solved by the development of digital recording and side by side cine loop display of two-dimensional echocardiograms: thus, respiratory artifacts can be eliminated, the examination is faster, and the comparison between rest and stress images has become practical and reliable improving sensitivity. The sensitivity and specificity of exercise echocardiography vary from 70 to 100%, according to patient selection, the protocol, and the gold standard used. Few studies studied the value of exercise echocardiography as compared to the more established nuclear cardiology imaging. Data from these comparative evaluations show a strong correlation between the two techniques for identifying and localizing myocardial ischemia. With good equipment and after proper training, exercise echocardiography can provide both diagnostic and prognostic information for routine clinical care.

Dobutamine stress-redistribution-reinjection versus rest-redistribution thallium-201 SPECT in the assessment of myocardial viability.

The aim of this study was to evaluate the value of thallium-201 chloride (201Tl) reinjection imaging following dobutamine stress (DRi) to identify viable myocardium in comparison with a rest-redistribution 201Tl protocol (RR). The identification of viable myocardium bears important consequences for adequate selection of patients with poor left ventricular function, often unable to exercise, who are considered for revascularization. Twenty-six patients with chronic coronary artery disease and depressed left ventricular function (ejection fraction 36 +/- 10%) were studied by both DRi and RR single photon emission computed tomography (SPECT). Semi-quantitative analysis of regional 201Tl activity (5-point score) and wall motion by echocardiography using a 16-segment model was performed. Regions were classified as viable (normal/reversible/fixed moderate defects) or non-viable (fixed severe defects) and related to regional wall motion. Target heart rate was reached in 25 patients. Myocardial viability was demonstrated in 353/416 (85%) by DRi SPECT and in 346/416 (83%) by RR SPECT. The agreement between the 2 protocols was 98% with a K-value of 0.94; similar results were obtained when the analysis was limited to dyscontractile segments. In conclusion, this study demonstrates the feasibility and diagnostic value of DRi SPECT to identify viable myocardium.