sodium-pertechnetate-tc-99m and Cardiomegaly

Left ventricular hypertrophy (LVH) is frequently present in patients referred for radionuclide ventriculography (RVG) for evaluation of left ventricular function. During interpretation of these studies, the nuclear medicine physician may have the subjective impression that increased septal thickening is present because of the abnormally prominent separation of the right and left ventricular blood pools. To examine the diagnostic reliability of this finding, we retrospectively reviewed the RVG studies of 43 consecutive patients and correlated the finding of subjectively increased septal thickness with established echocardiographic (ECHO) criteria and commonly used electrocardiographic (ECG) indices of LVH. Using standard ECHO measurements of septal thickness as a gold standard, RVG interpretation of septal thickening demonstrated a sensitivity of 0.69, specificity of 0.70, and accuracy of 0.70. When compared with standard ECG criteria for LVH, RVG performed quite favorably in the diagnosis of LVH confirmed by ECHO left ventricular mass index. We conclude that scintigraphic evidence of LVH should be reported when RVG studies are interpreted.

Topics: Adult; Aged; Aged, 80 and over; Cardiomegaly; Echocardiography; Electrocardiography; Erythrocytes; Female; Gated Blood-Pool Imaging; Humans; Male; Middle Aged; Retrospective Studies; Sodium Pertechnetate Tc 99m

The left ventricular function of 14 acromegalic patients was investigated using radionuclide ventriculography. After labeling the red blood cells with 750-1,000 MBq 99mTc-pertechnetate, ECG-triggered left anterior oblique images were recorded. Fourier analysis was then performed on the time-activity curve of the left ventricle. The ejection fraction (EF), peak ejection rate, time to peak ejection (TPE), time to end-systole (TES), peak filling rate (PFR), time to peak filling (TPF), 1/3 EF, 1/3 filling fraction (FF), TPE/T, TPF/T and TES/T values (T: time interval for one heart beat) were calculated for each patient. Five patients (35.7%) had clinical cardiovascular symptoms. A decreased EF was observed in 28.5% of the patients. In comparison to the control group, the EF (53.5 +/- 5.5 vs. 60.8 +/- 5% p less than 0.009), 1/3 EF (14.45 +/- 3 vs. 20 +/- 4%, p less than 0.001), 1/3 FF (28.5 +/- 10.6 vs. 41 +/- 11%, p less than 0.02), TPE (158 +/- 33 vs. 132 +/- 35 ms, p less than 0.01), TPE/T (20.2 +/- 5 vs. 16 +/- 3.7, p less than 0.01) and PFR (2.4 +/- 0.5 vs. 2.9 +/- 0.4 EDC/s, p less than 0.005) were significantly different. It was found that TPE was prolonged and the early ejection function was decreased. Diastolic dysfunction was found in 5 (35.7%) patients; 21.4% of the patients had decreased PFR values although they had no cardiac symptom, hypertension and/or cardiomegaly. Scintigraphic parameters did not correlate with the presence of hypertension, cardiomegaly or cardiovascular symptoms.(ABSTRACT TRUNCATED AT 250 WORDS)

Topics: Acromegaly; Adult; Cardiomegaly; Erythrocytes; Female; Gated Blood-Pool Imaging; Humans; Hypertension; Male; Myocardial Contraction; Sodium Pertechnetate Tc 99m; Ventricular Function, Left

The features of diastolic filling of the left ventricle (LV) were examined in relation to the nature of its hypertrophy in patients with coronary heart disease (CHD). A total of 110 male patients with CHD concurrent with essential hypertension or without it who underwent contrast ventriculography in order to determine LV diastolic stiffness. Radionuclide ventriculography was performed in 49 patients at rest and during exercise. The CHD patients with moderate LV concentric hypertrophy had more adequate LV diastolic filling in the presence of concurrent essential hypertension. Abnormal diastolic filling was more pronounced in CHD patients without hypertrophy or its eccentric development than in those without essential hypertension.

Topics: Adult; Cardiomegaly; Coronary Disease; Diastole; Hemodynamics; Humans; Male; Middle Aged; Radionuclide Ventriculography; Severity of Illness Index; Sodium Pertechnetate Tc 99m; Ventricular Function, Left

To evaluate the effects of long-standing systemic hypertension on left ventricular (LV) function during daily activities, ambulatory radionuclide monitoring of LV ejection fraction (EF) and blood pressure was performed during exercise and other structured activities in 31 hypertensive patients. Patients were divided into 3 groups based on the absence of LV hypertrophy (group 1 [n = 16], LV mass 107 +/- 12 g/m2), presence of LV hypertrophy without electrocardiographic changes (group 2 [n = 10], LV mass 141 +/- 8 g/m2) and LV hypertrophy with associated electrocardiographic changes (group 3 [n = 5], LV mass 158 +/- 9 g/m2). The groups were similar with respect to age, baseline medication, treated and untreated blood pressure, resting EF and treadmill exercise time. Patients in group 3 had the longest history of hypertension. Peak filling rate was normal in group 1 (2.9 +/- 0.4 end-diastolic volume/s), but reduced at rest in groups 2 (2.4 +/- 0.4) and 3 (2.1 +/- 0.3). Patients in group 1 had normal EF responses to exercise and mental stress testing, as well as during routine ambulatory activities. Patients in group 2 had a blunted EF response to exercise, and those in group 3 had a significantly abnormal response. Both group 2 and 3 patients demonstrated abnormal EF responses to mental stress, as well as cold pressor testing in association with significant increases in mean arterial pressure and marked reduction in diastolic filling rate. Decreases in EF were also observed during routine patient monitoring in 3 group 3 patients and 4 group 2 patients. These events were associated with significantly increased blood pressure.(ABSTRACT TRUNCATED AT 250 WORDS)

Topics: Adult; Ambulatory Care; Cardiomegaly; Cold Temperature; Echocardiography; Electrocardiography; Exercise Test; Humans; Hypertension; Male; Middle Aged; Monitoring, Physiologic; Radionuclide Imaging; Sodium Pertechnetate Tc 99m; Stress, Physiological; Stroke Volume; Ventricular Function, Left

Differential evaluation was carried out of hypertrophy as a factor possibly of compensatory or that of furthering disturbances of the coronary circulation and contractile function of the myocardium. Echocardiography, radionuclide ventriculography tests with physical loads revealed that only moderate hypertrophy of the left ventricle in IHD patients with hypertensive disease (grade II) may be considered as one of the compensatory factors maintaining the functional state of the left ventricle myocardium.

Topics: Cardiomegaly; Coronary Disease; Echocardiography; Exercise Test; Heart Ventricles; Hemodynamics; Humans; Hypertension; Myocardial Contraction; Radionuclide Imaging; Sodium Pertechnetate Tc 99m

Left ventricular diastolic filling measurements were determined by means of standard consecutive R-wave gating, list mode acquisition, and alternate R-wave gating. Time-activity curves obtained by the latter two methods were equally accurate in quantifying rapid, slow, and atrial left ventricular filling, whereas curves obtained by means of standard gating were inadequate for this purpose.

Topics: Cardiomegaly; Coronary Artery Disease; Diastole; Electrocardiography; Heart Ventricles; Humans; Hypertension; Male; Middle Aged; Myocardial Contraction; Radionuclide Angiography; Sodium Pertechnetate Tc 99m; Stroke Volume; Time Factors

Twelve healthy well-trained participants in a supervised exercise program (mean age, 41.3 yr) were compared with 12 sedentary control subjects (mean age, 38.9 yr) with physical characteristics similar to the exercised group (EG) before training. Resting echocardiograms revealed significantly lower heart rates (HR) in the EG compared with control group (CG) but no evidence for cardiac structural differences between groups. Radionuclide angiograms performed at rest and during two levels of supine cycling (HR targets: 120 and 140 beats X min-1) resulted in increases in background-corrected end-diastolic counts [EDC(bc)] and confirmed use of the Frank-Starling mechanism in the majority of subjects. Mean values (+/- SD) for ejection fraction (EF) and normalized peak systolic ejection rate (PSER) (P greater than 0.05 between groups) were the following. (Formula: see text) The results suggested that fitness training does not induce significant cardiac enlargement as apparent from measurements at rest or important changes in contractile state during exercise. Increases in exercise stroke volume with such training may be the result of an increased end-diastolic volume.

Topics: Adult; Cardiomegaly; Echocardiography; Erythrocytes; Female; Heart; Heart Rate; Humans; Male; Middle Aged; Myocardial Contraction; Physical Education and Training; Physical Exertion; Physical Fitness; Radionuclide Imaging; Sodium Pertechnetate Tc 99m; Stroke Volume; Time Factors; Ventricular Function

This study determines the noninvasive prognostic predictors (using radionuclide angiography) in patients with severe left ventricular dysfunction (resting ejection fraction less than or equal to 35 percent) secondary to coronary artery disease. We retrospectively evaluated 94 such patients using rest and exercise radionuclide ventriculography. At a mean follow-up of 16 months, cardiac events occurred in 22 patients: ten patients died of cardiac causes, five patients sustained nonfatal myocardial infarction, and seven patients developed severe congestive heart failure (class 4). Results indicate that patients with severe left ventricular dysfunction may be stratified into different risk groups according to left ventricular size. Marked left ventricular dilatation identifies a subgroup at high risk.

Topics: Actuarial Analysis; Adult; Aged; Cardiomegaly; Coronary Disease; Exercise Test; Female; Heart Ventricles; Humans; Male; Middle Aged; Prognosis; Rest; Retrospective Studies; Risk; Sodium Pertechnetate Tc 99m; Stroke Volume; Tomography, Emission-Computed

To study the pathologic and prognostic significance of--and possible underlying mechanisms for--a pathological exercise ECG in athletes, two age-matched groups were selected from a total population of 117 middle-aged and old endurance athletes: Group A: 21 with a pathological exercise-ECG, and group B: 21 with normal exercise-ECGs. Data from 201-thallium perfusion scintigraphy, 99 m-technetium multiple gated acquisition ventriculography (MUGA), resting echocardiography and 3 years follow-up are as follows: None had thallium findings indicating reversible myocardial ischaemia, but one from group A had a probable old myocardial infarction. All had normal resting MUGA, but group A men slightly more often presented a subnormal increase in ejection fraction according to exercise MUGA than group B men (9/20 vs 4/21). The former also more often had ventricular hypertrophy (LVH) (19/21 vs 14/21). However, apart from slightly longer ventricular filling time among group A men the echocardiograms revealed no group differences e.g. in cardiac dimensions or in indices of systolic or diastolic function. Regardless of exercise-ECG response, 18/42 athletes had one or more value of left ventricular dimensions or diameter exceeding the 95th percentile of the normal range. Since one patient from group A had asymmetric septal hypertrophy, one developed cardiomyopathy during the 3 years follow-up and one had a previous myocardial infarction, only 3/21 had cardiac disease which might explain the pathological exercise-ECG. Thus, pathological exercise-ECG rarely signifies heart disease in athletes, and very rarely coronary heart disease. Rather, the pathological exercise-ECG may be related to LVH and various subtle alterations in cardiac physiology following long-term endurance training.

Topics: Adult; Cardiac Output; Cardiomegaly; Coronary Disease; Echocardiography; Electrocardiography; Exercise Test; Follow-Up Studies; Heart Ventricles; Humans; Male; Middle Aged; Myocardial Contraction; Myocardial Infarction; Radioisotopes; Radionuclide Imaging; Skiing; Sodium Pertechnetate Tc 99m; Thallium

To evaluate the usefulness of two-dimensional echocardiography in asymptomatic or minimally symptomatic patients with significant aortic regurgitation and left ventricular enlargement, left ventricular size and function measurements obtained by a nongeometric technique, gated blood pool radionuclide angiography, were compared with measurements made by several two-dimensional echocardiographic methods in 20 patients. Left ventricular size was best assessed by an apical biplane modified Simpson's rule algorithm obtained by computer-assisted planimetry. For end-diastolic volume, r = 0.95 and standard error of the estimate = 25 ml; for end-systolic volume, r = 0.94 and standard error of the estimate = 16 ml. A newly introduced simplified two-dimensional method obviating the need for planimetry and using multiple axis measurements yielded satisfactory results, although volumes larger than 300 ml were markedly underestimated. Evaluation of volumes from a single minor axis measured directly from two-dimensional images and M-mode tracings obtained under two-dimensional echocardiographic control was inadequate for clinical use. Ejection fraction was correctly assessed by the modified Simpson's rule method as well as by the simplified two-dimensional method (r = 0.81 to 0.83, standard error of the estimate = 7%). However, when methods without planimetry were further simplified, a satisfactory correlation was no longer obtained. The M-mode approach using a corrected cube formula also provided an accurate estimation of ejection fraction, a finding that is attributed to the absence of regional wall motion abnormalities in this group of patients, the ability to locate the M-mode beam more adequately under two-dimensional control and the persistence of an ellipsoidal configuration and a circular cross section in the left ventricular chamber. The data indicate that two-dimensional echocardiography is a valuable approach to the assessment of left ventricular size and function in these patients. Moreover, this approach provides a practical and convenient way of improving M-mode evaluation of function and of determining left ventricular shape, thus permitting adequate selection of geometric algorithms for volume calculations.

Topics: Adult; Aged; Aortic Valve Insufficiency; Cardiomegaly; Computers; Echocardiography; Heart; Humans; Middle Aged; Radionuclide Imaging; Sodium Pertechnetate Tc 99m; Stroke Volume