Blood flow-metabolism imaging with positron emission tomography in patients with diabetes mellitus for the assessment of reversible left ventricular contractile dysfunction.
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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. (+info)
Maternally transmitted susceptibility to non-insulin-dependent diabetes mellitus and left ventricular hypertrophy.
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OBJECTIVES: We studied the association of diabetes transmission with left ventricular hypertrophy (LVH) in patients with non-insulin-dependent diabetes mellitus (NIDDM). BACKGROUND: It is suggested that NIDDM has a strong genetic basis and that maternally transmitted NIDDM is associated with mitochondrial deoxyribonucleic acid (DNA) mutations. However, genetic factors for LVH in NIDDM are unknown. METHODS: We investigated the family history of diabetes and the prevalence of LVH using electrocardiography in 834 patients with NIDDM, of whom 199 also underwent echocardiography. RESULTS: Of the 834 patients, 121 had diabetic mothers, 122 had diabetic fathers and 30 had both. The LVH criterion of S(v1) + R(V5) or R(v6) >35 mm was met in 148 patients. The percentage of patients having diabetic mothers was higher in those with LVH criterion (29%) than without it (16%) (p < 0.001), but the percentage of patients having diabetic fathers was similar in those with LVH (18%) and without it (18%). Compared with the 683 patients with nondiabetic mothers, the 151 patients with diabetic mothers were younger and had earlier onset of diabetes. The percentage of patients having diabetic siblings was also higher in those with diabetic mothers (31%) than in those with nondiabetic mothers (18%) (p < 0.001). On electrocardiograms, the prevalence of LVH was higher in patients with diabetic mothers (28%) than in those with nondiabetic mothers (15%) (p < 0.001). Echocardiograms showed that patients with diabetic mothers had greater left ventricular wall thickness and mass than those with nondiabetic mothers. In multivariate analysis, the family history of diabetes in mothers was an independent factor to LVH, but the family history of diabetes in fathers was not. CONCLUSIONS: Maternal transmission of diabetes was associated with LVH in patients with NIDDM. Some genetic factors of diabetes, such as mitochondrial DNA abnormalities, may contribute to the development of LVH in maternally transmitted NIDDM. (+info)
Beneficial effect of myocardial angiogenesis on cardiac remodeling process by amlodipine and MCI-154.
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The present study examined the effect of long-term treatment with amlodipine and MCI-154 (a Ca2+ sensitizer) on progressive cardiac dysfunction and microvasculature in the dilated cardiomyopathic (DCM) hamster heart. After treatment of DCM hamsters (Bio 53.58) with amlodipine or MCI-154 for 15 wk from the age of 5 wk, amlodipine and MCI-154 were found to cause an increase in left ventricular percent fractional shortening and decreases in left ventricular diastolic dimension and isovolumic relaxation time in echocardiograms (P < 0.01). A hemodynamic study showed that the diastolic time constant decreased in the amlodipine-treatment group (P < 0.05). In a morphometric study employing a double-staining method that discriminated arteriolar and venular capillaries, amlodipine and MCI-154 caused increases in total capillary density (P < 0.05) and the proportion of venular capillaries (P < 0.05). Moreover, Northern blot analysis showed that the expression of mRNA for vascular endothelial growth factor was significantly increased by amlodipine and MCI-154. They preserve coronary microvasculature in the DCM hamster and might induce angiogenesis of small vessels, thereby contributing to preservation of cardiac systolic and diastolic function. (+info)
Fas expression and apoptosis correlate with cardiac dysfunction in patients with dilated cardiomyopathy.
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Fas is a transmembranous glycoprotein that mediates apoptosis. To elucidate the roles of Fas and of myocyte apoptosis in patients with dilated cardiomyopathy (DCM), the expression of Fas and the fragmentation of DNA were compared in endomyocardial biopsy specimens obtained from patients with DCM. Endomyocardial biopsy was performed on 19 subjects (16 with DCM and 3 control subjects) who also underwent cardiac catheterization and echocardiography. Fas and bcl-2 expression were assayed immunohistochemically, and in situ TdT staining was performed to estimate the number of apoptotic cells. Samples from the DCM patients stained more intensely with anti-Fas antibody than those from control patients (p<0.05). The percentage of in situ TdT-positive cells was significantly higher in the DCM group than in the control group (p<0.05). A correlation between Fas expression and in situ TdT staining was observed in 67% of myocytes in the DCM group. Moreover, the percentage of in situ TdT staining was significantly higher in subjects with severely impaired left ventricular systolic function than in those whose systolic function was mild to moderately impaired, or who had normal systolic function (p<0.05). The samples showed little expression of bcl-2. These results suggest that Fas expression and apoptosis may be involved in the progression of cardiac dysfunction in DCM. (+info)
Left ventricular end-systolic wall stress is a potent prognostic variable in patients with dilated cardiomyopathy.
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Dilated cardiomyopathy is an important cause of morbidity and mortality among patients with heart failure. Left ventricular dilation is viewed as a compensatory response to maintain stroke volume, and left ventricular dilation is directly related to the increase of wall stress. However, only a few studies have examined whether wall stress can be a prognostic variable in patients with dilated cardiomyopathy. This study was designed to elucidate whether left ventricular systolic wall stress was related to the prognosis in patients with dilated cardiomyopathy. Twenty-five normal control subjects and 68 patients with dilated cardiomyopathy participated in this study. Hemodynamic parameters and left ventricular systolic wall stress were determined using echocardiography. In addition, the extent score determined by thallium-201 myocardial scintigraphy was measured as an index of cumulative loss of myocardium. During the 53-month follow-up period, 13 patients died of cardiac events. In a stepwise multivariable analysis, end-systolic wall stress and fractional shortening were significant predictors of survival. The extent score was markedly greater in the patients who died than in alive patients. There was a significant correlation between end-systolic wall stress and extent score (r=0.501, p=0.0001). Left ventricular end-systolic wall stress is an important predictor of mortality in patients with dilated cardiomyopathy. (+info)
Assessment of the temporal relationship between left ventricular relaxation and filling during early diastole using pulsed Doppler echocardiography and tissue Doppler imaging.
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The study investigated the temporal relationship between left ventricular (LV) relaxation and filling during early diastole. The transmitral flow (TMF) velocity by pulsed Doppler echocardiography and LV wall motion velocity by pulsed tissue Doppler imaging (TDI) were evaluated in 57 patients with various heart diseases and 33 normal controls. The patients were classified into 2 groups according to the ratio of the peak early diastolic to atrial systolic TMF velocity (E/A): (1) the high A group included 44 patients with an E/A < or = 1, and (2) the pseudonormalization group included 13 patients with an E/A > 1. The isovolumic relaxation time (IRT) from the aortic component of the second heart sound (IIA) to the onset of the E wave of the TMF was measured. The peak early diastolic velocity of the LV posterior wall (Ew) and time from the IIA to the onset of the early diastolic wave (IIA-Ewo) were determined from the LV wall motion velocity assessed by pulsed TDI. The Ew was lower in the pseudonormalization and high A groups than in the control group. The IIA-Ewo was significantly longer in the pseudonormalization and high A groups than in the control group. The time constant of the LV pressure decay at isovolumic diastole (tau) correlated negatively with the Ew, and correlated positively with the IIA-Ewo in all groups. The IIA-Ewo was equal to or shorter than the IRT in control subjects, and was longer than the IRT in patients in the pseudonormalization group. In conclusion, the temporal relationship between LV relaxation and filling during early diastole varied according to the subjects' hemodynamic status. Analysis of TMF by pulsed Doppler echocardiography and LV wall motion velocity by pulsed TDI was useful for detailed evaluation of early diastolic LV hemodynamics. (+info)
Myocardial stunning caused by sympathetic nerve injury after an operation on cervical vertebrae.
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In this case, electrocardiographic inverted T waves appeared after cervical laminaplasty and echocardiogram showed temporary wall motion abnormality. Myocardial metaiodobenzylguanidine (MIBG) uptake was obviously reduced in the same area where the wall motion abnormalities appeared in the echocardiogram, although no abnormalities were detected with myocardial thallium scintigraphy and coronary angiography. The myocardial stunning was caused by injury to the sympathetic nerves from a surgical procedure on the cervical vertebrae. (+info)
Cardiac function and haemodynamics in alcoholic cirrhosis and effects of the transjugular intrahepatic portosystemic stent shunt.
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BACKGROUND: A portosystemic stent shunt may impair cardiac function and haemodynamics. AIMS: To investigate the effects of a transjugular intrahepatic portosystemic shunt (TIPS) on cardiac function and pulmonary and systemic circulation in patients with alcoholic cirrhosis. PATIENTS/METHODS: 17 patients with alcoholic cirrhosis and recent variceal bleeding were evaluated by echocardiography and catheterisation of the splanchnic and pulmonary circulation before and after TIPS. The period of catheter measurement was extended to nine hours in nine of the patients. The portal vein was investigated by Doppler ultrasound before and nine hours after TIPS. RESULTS: Baseline echocardiography showed the left atrial diameter to be slightly increased and the left ventricular volume to be in the upper normal range. Nine hours after TIPS, the left atrial diameter and left ventricular end diastolic volume were increased (by 6% (p<0.01) and 7% (p<0.01) respectively); end systolic volume had not changed significantly. Invasive measurements showed a sharp increase in right atrial pressure (by 101%; p<0.01), mean pulmonary artery pressure (by 92%; p<0.01), pulmonary capillary wedge pressure (by 111%; p<0.01), and cardiac output (8.1 (1.6) to 11.9 (2.4) l/min; p<0.01). Systemic vascular resistance decreased (824 (242) to 600 (265) dyn.s.cm-5 p<0.01), and total pulmonary resistance increased (140 (58.5) to 188 (69.5) dyn.s.cm-5; p<0.05). Total pulmonary resistance (12%; NS), cardiac output (1.4 l/min; p<0. 05), and portal vein blood flow (1.4 l/min; p<0.05) remained elevated for nine hours after TIPS in the subgroup. Portoatrial pressure gradient (43%; p<0.05), portohepatic vascular resistance (72%; p<0.05), and systemic vascular resistance (27%; p<0.01) were consistently reduced. CONCLUSIONS: The increase in the left atrial diameter, the pulmonary capillary wedge pressure, and total pulmonary resistance observed after the TIPS procedure reflected diastolic dysfunction of the hyperdynamic left ventricle in patients with alcoholic cirrhosis. The haemodynamic effects of the portosystemic stent shunt itself on the splanchnic circulation seem to be mainly responsible for the further decrease in systemic vascular resistance. TIPS may unmask a coexisting preclinical cardiomyopathy in patients with alcoholic cirrhosis and portal hypertension. (+info)