technetium-tc-99m-tetrofosmin and Diabetes-Mellitus--Type-2

Cardiovascular disease is the most frequent cause of death and disability in diabetes, and the morbidity and mortality for coronary artery disease (CAD) in this population is two to four times higher than in nondiabetic subjects. Traditional risk factors do not fully explain the level of cardiovascular risk, and coronary disease events are often silent in diabetic patients. Thus, research has recently focused on improving the risk assessment of an individual patient with new tools in an effort to better identify subjects at highest risk and in need of aggressive management. Cardiovascular imaging has proven very helpful in this regard. Traditional methods to assess CAD are based on detection of obstructive luminal disease responsible for myocardial ischemia. However, acute coronary syndromes often occur in the absence of luminal stenoses. Hence, the utilization of imaging methodologies to visualize atherosclerosis in its presymptomatic stages has received mounting attention in recent years. In this article, we review the current literature on the utility of traditional imaging modalities for obstructive CAD (nuclear and echocardiographic stress testing) as well as atherosclerosis plaque imaging with carotid intima-media thickness and coronary artery calcium for risk stratification of diabetic patients.

Topics: Cardiovascular Diseases; Coronary Artery Disease; Diabetes Complications; Diabetes Mellitus; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Echocardiography, Stress; Humans; Magnetic Resonance Angiography; Myocardial Ischemia; Organophosphorus Compounds; Organotechnetium Compounds; Radiography; Risk Management; Technetium Tc 99m Sestamibi; Thallium Radioisotopes; Tomography, Emission-Computed, Single-Photon; Tunica Intima; Tunica Media

Topics: Aged; Cardiology; Chest Pain; Diabetes Mellitus, Type 2; Esophageal Neoplasms; Esophagectomy; Gastroesophageal Reflux; Humans; Hyperlipidemias; Hypertension; Male; Microcirculation; Organophosphorus Compounds; Organotechnetium Compounds; Risk Factors; Single Photon Emission Computed Tomography Computed Tomography; Stroke; Technetium Tc 99m Sestamibi

Incidence of early myocardial changes in asymptomatic diabetic individuals is not clearly documented. In the present study, we examined diabetic patients without a history of cardiovascular disease with negative treadmill test and no signs of systolic dysfunction for presence of cardiac autonomic neuropathy established by measurement of heart rate variability (HRV) and (99m)Tc - Myoview gated-SPET.. 47 type I and type II diabetic patients were subjected to prospective study including echocardiography and HRV measurement using the combination of Ewing´s testing and spectral analysis. Subsequently, patients underwent treadmill test and stress myocardial perfusion scintigraphy. Additionally, vascular and metabolic parameters were collected.. Treadmill test was negative in all patients. Diastolic dysfunction was found in 10 % of T1DM and 11 % of T2DM patients by echocardiography, whereas none of the patients had systolic dysfunction. SPET confirmed hypoperfusion in 35 % T1DM (p=0.01) and in 60 % T2DM (p=0.001). Diagnosis of cardiac autonomic neuropathy based on Ewing´s testing and HRV examination was established in 60 % of T1DM patients (p=0.001) and 77 % of T2DM patients (p=0.001). In T1DM group, significant association was found between cardiac autonomic neuropathy (CAN) and frequency of hypoglycaemia (p=0.04). No such correlations were found in patients with T2DM.. The results of the present study show high incidence of myocardial hypoperfusion and cardiac autonomic neuropathy among asymptomatic diabetic patients, whereas the standard diagnostic approaches including treadmill test and echocardiography failed to show any changes. Therefore, we conclude that diabetic heart disease remains underdiagnosed by standard approaches, but could be detected in asymptomatic patients by more sensitive methods, such as HRV measurement and myocardial scintigraphy (Tab. 2, Fig. 2, Ref. 26).

Topics: Adult; Asymptomatic Diseases; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Diabetic Angiopathies; Diabetic Neuropathies; Female; Heart; Heart Rate; Humans; Male; Middle Aged; Myocardium; Organophosphorus Compounds; Organotechnetium Compounds; Radiography; Radiopharmaceuticals; Tomography, Emission-Computed, Single-Photon

This study was designed to determine the clinical risk for hard events after normal single-photon emission computed tomography (SPECT) and to identify the predictors of increased risk in asymptomatic patients with diabetes mellitus, based on a Japanese Assessment of Cardiac Events and Survival Studies by quantitative gated SPECT (J-ACCESS)-2 study.. A total of 513 consecutive asymptomatic patients who underwent stress (99m)Tc-tetrofosmin SPECT in Japan were included in this study. Based on SPECT image and QGS data, 319 had a summed stress score < or =3, a summed difference score <2 and normal cardiac function (end-systolic volume < or =60 ml, males, < or =40 ml, females; left ventricular ejection fraction > or =49%, males, > or =50%, females). Myocardial perfusion was normal in 62% of this study population. During a 3-year follow-up, there were a total of 8 cardiac major events (2.5%): 2 cases of sudden death, 5 of acute coronary syndrome, and 1 of hospitalization because of congestive heart failure. The annual major event rate was 0.8%. Subjects undergoing coronary angiography had significantly more major events than those who did not among normal SPECT subjects (P=0.01). Kaplan-Meier analysis showed that the cardiac major events rate was very low, and subjects with normal SPECT can be considered as low risk among asymptomatic patients with diabetes.. An excellent prognosis was associated with a normal SPECT in asymptomatic patients with diabetes, so these patients can be exempted from further invasive procedure.

Topics: Asian People; Cardiovascular Diseases; Coronary Angiography; Diabetes Mellitus, Type 2; Diagnostic Techniques, Cardiovascular; Female; Humans; Male; Organophosphorus Compounds; Organotechnetium Compounds; Prognosis; Tomography, Emission-Computed, Single-Photon; Ventricular Function

This study sought to find among clinical, hemodynamic and left ventricular perfusion and function data obtained from myocardial perfusion scintigraphy (MPS), those associated with a reduced heart rate (HR) response to dipyridamole in diabetic patients. This phenomenon, although previously described as a marker of autonomic dysfunction in patients with diabetes, has not been fully elucidated.. One hundred two consecutive diabetic patients undergoing dual-isotope (rest Tl-201/dipyridamole stress Tc-99m tetrofosmin) MPS were prospectively enrolled. A reduced HR response to dipyridamole was considered present if the ratio between maximal HR after dipyridamole infusion and rest HR was

Topics: Aged; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Dipyridamole; Female; Heart Rate; Humans; Male; Middle Aged; Myocardial Perfusion Imaging; Organophosphorus Compounds; Organotechnetium Compounds; Radiopharmaceuticals; Ventricular Dysfunction, Left

Global and regional myocardial uptake was determined with technetium-99m tetrofosmin and a 4 hour exercise (370 MBq i.v.) and rest (740 MBq i.v.) protocol, in 24 patients with non-insulin dependent diabetes mellitus and in 22 control subjects. The purpose of this study was to evaluate impaired coronary microvascular function in diabetics by measurement of % uptake increase in myocardial counts. The parameter of % uptake increase (deltaMTU) was calculated as the ratio of exercise counts to rest myocardial counts with correction of myocardial uptake for dose administered and physical decay between the exercise study and the rest study. Global deltaMTU was significantly lower in the diabetics than in control subjects (14.4 +/- 5.4% vs. 21.7 +/- 8.5%, p < 0.01). Regional deltaMTU in each of 4 left ventricular regions (anterior, septal, inferior, posterolateral) was significantly lower in the diabetic group than in the control group (p < 0.01) respectively, but there were no significant differences between deltaMTU in the 4 left ventricular regions in the same group. deltaMTU was useful as a non-invasive means of evaluating impaired coronary microvascular function in diabetics.

Topics: Blood Pressure; Coronary Circulation; Coronary Disease; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Diabetic Angiopathies; Exercise Test; Female; Heart; Heart Rate; Hemodynamics; Humans; Male; Microcirculation; Middle Aged; Myocardium; Organophosphorus Compounds; Organotechnetium Compounds; Radiopharmaceuticals; Reference Values; Regression Analysis; Tissue Distribution; Tomography, Emission-Computed, Single-Photon

The purpose of this study was to evaluate oxidative metabolism and its response by dobutamine in patients with noninsulin-dependent diabetes mellitus (NIDDM) using 11C-acetate PET.. We studied 16 patients with NIDDM (9 men, 7 women; mean age 53.7 +/- 12.8 yr) and 6 healthy male control subjects (mean age 41.8 +/- 17.2 yr). None of them had an abnormality on stress-perfusion SPECT. The 11C-acetate clearances (Kmono) were compared regionally for five myocardial segments in all subjects at rest and during low-dose dobutamine stress in 13 patients (8 patients with NIDDM, age 51.9 +/- 13.6 yr; 5 healthy male control subjects, age 45.6 +/- 16.3 yr). Correlation between regional Kmono and rate-pressure product (RPP) was also studied.. At rest, the clearance of 11C-acetate was slightly heterogeneous for both patients with NIDDM and healthy control subjects, with smaller values in the apex and inferior wall in both groups. The difference became significant during dobutamine stress in the patients. The RPP-to-Kmono (average for five segments) ratio at rest was slightly smaller in the patients (1042.7 +/- 559.1 x 0.01) than in the healthy control subjects (1391.4 +/- 209.6 x 0.01, not significant), and those during dobutamine stress were almost the same in the two groups (1457.3 +/- 737.4 x 0.01 and 1486.0 +/- 211.8 x 0.01, respectively). A significant correlation was seen between regional Kmono and RPP in every segment in the healthy control subjects (average; r = 0.89; p < 0.01), whereas more scattered correlation with greater regional variation was observed in the patients (average; r = 0.31; p value was not significant).. Patients with NIDDM showed slight regional heterogeneity in myocardial oxidative metabolism. They also had more scattered correlation between myocardial oxidative metabolism and cardiac work (RPP) than healthy control subjects, with the smallest correlation coefficient observed in the inferior wall. These findings may help the understanding of dynamics in myocardial oxidative metabolism of NIDDM hearts.

Topics: Acetates; Adrenergic beta-Agonists; Adult; Carbon Radioisotopes; Case-Control Studies; Diabetes Mellitus, Type 2; Dobutamine; Female; Heart; Humans; Male; Middle Aged; Myocardium; Organophosphorus Compounds; Organotechnetium Compounds; Oxygen Consumption; Radiopharmaceuticals; Tomography, Emission-Computed; Tomography, Emission-Computed, Single-Photon