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The objective of this study was to test if three-dimensional (3-D) ultrasound (US) provides accurate determination of the cardiac volumes and ejection fraction. The 3-D device (Model 1-Volumetrics, ) is a 3-D acquisition system using a 2-Mhz matrix probe that insonates the whole cardiac volume in a 4-chamber view and collects the entire backscattered US echoes from this volume within one cardiac cycle. The complete 3-D US information stored in the memory can then be cut into 2-D views of any arbitrary orientation. For volume determination, the best 4-chamber view was selected into the memory, then 6 transverse views were displayed at different depths along the ventricle long axis, and the contour of the ventricle was drawn on each of these views. The left ventricle volume in diastole (LVDV) and the ejection fraction (EF) obtained by 3-D US were compared with those from x-ray and isotopic angiographies, and 2-D echo-time motion (2-D Echo-TM). The variations in stroke volume (SV) during a stand test, measured by 3-D US, and aortic Doppler were compared. The correlation between EF evaluated from 3-D US and x-ray or isotopic angiographies was found to be good (r = 0.80 p < 0.001; r = 0.86 p < 0.001), but lower with 2-D Echo-TM (r = 0.59 p < 0.001). For LVDV, the correlation was acceptable with x-ray angiography (r = 0.75 p < 0.001), but much lower with isotopic angiography and 2-D Echo-TM (r = 0.47 p < 0.001; r = 0.55 p < 0.001). A good correlation was also found between the SV changes measured by 3-D US and aortic Doppler (r = 0.79 p < 0.001).

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Condensed image processing (CIP), a computerized technique of scintiscans that generates a vertical distribution of activity as a function of time in a single image, was applied to isotopic lymphoscintigrams of four patients with leg lymphedema. By "condensing" information gained from multiple images into a single image, CIP better evaluates ascending progression of radiolabeled colloid in peripheral lymph and better localizes stagnant areas. In "high lymph flow failure," CIP also depicts radioactive "bursts" suggestive of increased lymphatic truncal contractility. This data processing method improves interpretation of dynamic scintiscan recordings and seems ideally suited for evaluation of peripheral lymph kinetics.

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Twenty-seven patients (15 men, 12 women; mean age 48.9 years) suffering from ventricular tachycardia (VT) (n = 30) were studied by radionuclide angiocardiography with Fourier phase analysis, both in sinus rhythm and during tachycardia. VT was spontaneous, electrically inducible, sustained, haemodynamically stable and monomorphous, with a mean rate of 174 beats/min (range: 115-260 beats). Heart diseases responsible for VT were: non-obstructive cardiomyopathy (n = 7), hypertrophic cardiomyopathy (n = 1), ischaemic heart disease (n = 5), probable right ventricular arrhythmogenic dysplasia (n = 4), congenital left ventricular aneurysm (n = 2), sequela of myocarditis (n = 2) and aortic valve regurgitation (n = 1); no heart disease was detectable in 5 patients. On surface electrocardiogram there was good concordance between the initial radionuclide site of VT activation and the configuration and electrical axis of QRS. At Fourier phase analysis all 17 VT of the right lag type originated in the left ventricle, arising from the apical septum (n = 7) or lateral segment (n = 2) in case of left axis, from the basal segment (n = 6) or the lateral segment (n = 1) in case of vertical or right axis, and from the middle left septum (n = 1) in case of normal axis. Nine VT of the left lag type originated in the right ventricle, arising from the basal septum or the latero-basal region in case of vertical or right axis (n = 6), from the apical septum or the inferior-apical region in case of left axis (n = 2) and from the middle septum in case of normal axis (n = 1). Four of our patients (3 with coronary disease and 1 with congenital left ventricular aneurysm) had VT of the left lag type and an initial radionuclide site of activation in the middle part of the left septum in case of left axis (n = 2) and in the basal part of that septum in case of right axis (n = 2). Seven patients were operated upon for recurrent VT: 4 had intra-operative mapping which in every case confirmed the results of radionuclide angiocardiography, a method which in the other 3 patients was the only surgeon's guide. Correlations between the site of origin of VT at radionuclide mapping and kinetic abnormalities visualized at radiological angiography and gamma-ray angiocardiography were common in our study. In one of our patients the same lesion gave birth to 2 VT of different morphologies.(ABSTRACT TRUNCATED AT 400 WORDS)

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The standard deviation of the first harmonic Fourier phase histogram is an indicator of the contraction heterogeneity of the heart ventricles. This approach has been applied to analyse tomographic blood pool (99mTc) examinations in a group of 32 patients with angiographically verified mainly right (RV) but also left (LV) kinetic disorders in relation to severe ventricular arrhythmias and suspicion of arrhythmogenic right ventricular dysplasia (ARVD). The reference group consisted of ten patients with low probability of cardiac kinetic abnormalities. Thick tomographic slices including both ventricles have been reconstructed in the horizontal long axis orientation from a series of 32 gated projections recorded over a 360 degrees rotation. Separately for each ventricle the Fourier phase histograms have been computed and characterized by their standard deviations (PSD). Normal values (mean +/- standard deviation, LV = 11 degrees +/- 5 degrees, RV = 12 degrees +/- 5 degrees) were significantly lower (P less than 0.01 and P less than 0.001) than those measured in abnormal cases (LV = 19 degrees +/- 10 degrees and RV = 31 degrees +/- 17 degrees). Detailed analysis of the data supports the hypothesis of a primary RV disease in ARVD, with secondary LV extension. PSD seems to be a good predictor of an organic cardiac disease underlying ventricular arrhythmias and may be used for screening the patients.

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The authors report 3 cases of acromegaly diagnosed while the patients were in hospital for cardiovascular disease: arterial hypertension in two and hypertrophic myocardiopathy in all three. Coronary arteriography was normal in the 3 patients. The exercise-induced dyspnoea observed in these 3 cases was unexplained by right and left cardiac catheterization results (normal pressures, normal or increased cardiac index). It was most probably related to the myocardial hypertrophy and to abnormalities in diastolic function demonstrated by radioisotopic methods in patients 2 and 3. The degree of myocardial hypertrophy present in these 3 patients seemed to correlate with the size of the pituitary adenoma and the plasma level of growth hormone rather than with the duration or degree of arterial hypertension. After excision of the pituitary adenoma hypertension persisted in 1 case, due to associated adrenal gland hyperplasia, and subsided in the other cases. Abnormalities of diastolic function and dyspnoea are gradually regressing but left ventricular hypertrophy has not significantly decreased after 6 post-operative months.

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In a randomized, double-blind, cross-over study with plasma drug assays, 16 patients (11 men, 5 women; mean age 48.56 +/- 3.61 years) presenting with hypertrophic obstructive cardiomyopathy confirmed by echocardiography, left ventriculography and left intraventricular gradient measurement were treated with verapamil 480 mg/day or propranolol 320 mg/day. Both treatments produced functional improvement (p less than 0.01) which was more distinct with verapamil (NS). No changes in cardiothoracic index, echocardiographic parameters and Sokolow's index were observed. Mean total heart work during exercise, which was 1,197.27 +/- 135.89 watts before treatment, increased to 1,260.91 +/- 146.60 watts under propranolol (NS) and to 1,344.09 +/- 171.06 watts under verapamil (NS). Maximum heart rate during exercise, which was 162.3 +/- 3.46 beats/min before treatment, was reduced to a greater extent by propranolol (122.1 +/- 6.6 beats/min; p less than 0.001) than by verapamil (147.7 less than 5.08 beats/min; p +/- 0.01). The two treatments did not significantly modify ventricular arrhythmia, arterial and capillary pulmonary pressures, mean aortic pressure and left ventricular end-systolic pressure. Cardiac index, unchanged under verapamil, fell from 2.98 +/- 0.16 1 X min-1 X m-2 to 2.60 +/- 0.11 1 X min-1 X m-2 under propranolol (p less than 0.05). The left intraventricular gradient present in 5 patients at rest and during exercise, was reduced by both drugs. The gradient under isoprenaline (n = 16), which was 162.07 +/- 18.77 mmHg before treatment, fell to 93.86 +/- 24.48 mmHg with propranolol (p less than 0.05) and to 128.86 +/- 18.22 mmHg with verapamil (p less than 0.05). Left ventricular ejection fraction, mean circumferential fibre shortening speed and compliance coefficient remained unchanged under both drugs (NS). Left ventricular diastolic function, evaluated by radioisotope angiography in the last 9 patients, was most often improved by verapamil (NS). Verapamil was better tolerated generally and by the heart than propranolol. No correlation was observed between plasma verapamil levels and clinical results. Low plasma propranolol levels were often noted in non-responders, suggesting a need for treatment with high doses. It is concluded that at the dosage level used in this study propranolol and verapamil were equally effective, but there were individual variations in best response to one or the other of these two drugs.

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Oxygen affinity of haemoglobin is modulated by several parameters such as the allosteric effector 2-3 DPG for most mammalians. Inositol hexaphosphate (I.H.P.) exerts the same effect on haemoglobin. A previously developed new methodology for the entrapment of drugs into erythrocytes has been adapted to I.H.P.; it is based on a reversible osmotic shock. I.H.P. loaded red blood cells have characteristics very similar to those of native cells. The decrease in oxygen affinity is related to the dose of encapsulated I.H.P. In piglets, transfusion of such cells has led to an increase of oxygen extraction from haemoglobin. Normal anesthetized animals regulate their oxygen consumption by reduction of cardiac output.

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Twenty-three patients with chronic aortic incompetence (17 men and 6 women) aged 27 to 71 years (average 51 years) underwent sequential gamma-angiography at rest and during the different levels of exercise and recovery phase to investigate the evolution of ventricular function and regurgitant fraction and so, guide therapy. The radionuclide indices of left ventricular function (end diastolic and end systolic indexed volumes, global ejection fraction, regional wall motion) and the regurgitant fractions were calculated and compared with clinical, echocardiographic, angiographic and haemodynamic data. The changes observed on effort during gamma-angiography allowed identification of 3 groups of patients: Group I: compensated aortic incompetence with a normal left ventricular ejection fraction (0.69 +/- 0.1), a moderate regurgitant fraction (40 per cent +/- 20 per cent) and, during exercise, a stable left ventricular end diastolic volume index (less than 5 per cent variation), an end systolic volume index which decreased (average-13 per cent), an ejection fraction which increases (by more than 0.05 in 62.5 per cent of cases) and with good global and regional wall motion. Group II: intermediate cases with a left ventricular ejection fraction of 0.62 +/- 0.09 and a regurgitant fraction of 60 +/- 16 per cent. Individual variations were observed with this group which either resembled those of Group I or those of Group III.(ABSTRACT TRUNCATED AT 250 WORDS)

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Images of radioactive tracer uptake are mainly functional images since the tracer distribution may directly be related to the regional variations in function, such as myocardial perfusion in the case of thallium-201 single photon tomography. Combination of pictures obtained in different physiological conditions (stress-rest, for instance) enhance the functional aspects of these studies. For gated cardiac blood pool images, on the contrary, labelling of the circulating blood pool using technetium-99m provides morphological pictures of the heart chambers and function can only be derived from the dynamic analysis of the image sequence recorded at the successive phases of the cardiac cycle. The technique of 'thick slice' tomography preserves the relationship between count rates and local volumes of radioactive blood. Parametric imaging therefore applies to tomography as well as to plane projections. In the simplest case reconstruction of the extreme phases of the heart beat, end-diastole and end-systole may be sufficient. But to achieve more sophisticated functional analysis such as Fourier phase mapping, reconstruction of the whole cardiac cycle is necessary.

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