One hundred and seventy-two patients (110 were &ge; 65 years and 62 were <65 years) with congestive heart failure (CHF) were prospectively evaluated to determine various pathophysiologic mechanisms of CHF. The incidence of CHF with normal left ventricular (LV) systolic function was higher in elderly (30% vs 12%, p<0.05). Of the 110 elderly patients. LV systolic function was impaired in 77. Fifty-five patietns had LV dilatation without increased wall thickness, and the clinical diagnosis was "dilated cardiomyopathy in the elderly". Twenty-two patients had hypertrophied LV and a high incidence of hypertension, and they were diagnosed as "hypertensive heart failure" due to contractile dysfunction. On the contrary, the remaining 33 patients did not have impaired LV contractile function. Thirteen patients lacking LV hypertrophy had enlarged atria. CHF was induced by reduced chamber compliance called "the stiff heart syndrome". Twenty patients had hypertrophied LV and a high incidence of hyper-tensron They were diagnosed as having "hypertensive hypertrophic cardiomyopathy of the elderly" and abnormalities of diastolic function accounted for the CHF. Since echocardiography can easily and accurately diagnose the pathophysiologic mechanism of CHF, an increased awareness of its occurrence in the elderly and use of echocardiography would reduce diagnostic and therapeutic errors.

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Background: The purpose of this study is to report our experience regarding the acute and intermediate-term results of balloon pulmonary valvuloplasty (BPV) in various types of congenital pulmonary valve stenosis. Methods and Results: Twenty-four consecutive patients with a median age of 6.6 years (ranging from I month to 24 years old) underwent BPV between January 1988 and September 1991. These patients were divided into 2 groups; Group I consisting of 13 patients with isolated pulmonary valve stenosis, and Group 2 consisting of 11 patients with complicated pulmonary valve stenosis (supravalvular, subvalvular, valved conduit and post-right ventricular outflow reconstruction). Mean peak systolic pressure gradients from the right ventricle to the pulmonary artery were as follows: In group 1, 48±21 (mean±SD) mmHg before BPV, 18±8 mmHg immediately after BPV and 13±5 mmHg at the longest follow-up based on catheterization or Doppler echocardiographic studies. The gradients in group 2 were 65±28 mmHg before BPV, 46±25 mmHg immediately after BPV and 47±21 mmHg at the longest follow-up. Conclusions: BPV provides both acute and intermediate-term gradient relief in patients with isolated pulmonary valve stenosis. In complicated pulmonary valve stenosis, on the other hand, the effect of BPV was unsatisfactory and appears to depend on the mechanism of associated obstruction. Therefore accurate evaluation of the anatomy of associated obstruction in the pulmonary valve region is needed to determine that BPV is indicated.

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To investigate the effects of hypoxia and nitroglycerin on pulmonary vascular tone, multipoint mean pulmonary arterial flow-pressure (Q-P relationship) plots were constructed by producing stepwise increments of pulmonary flow with a roller pump installed in a right ventricle-pulmonary artery shunt in 12 mongrel dogs under pentobarbital sodium anesthesia. The normal Q-P relationship was convex to the pressure axis when pulmonary flow was 0-0.2 L/min, but it became linear when pulmonary flow was over 0.2 L/min. The slopes and pressure intercepts extrapolated (RAPI) from linear regression fits to the linear parts of the Q-P relationship were determined to compare the effects of hypoxia and nitroglycerin on pulmonary vascular tone. Hypoxic ventilation (F_IO₂: 0.1) increased the slope from 8.3±3.3 to 12.5±3.6 mmHg/L (p<0.01), with no significant effect on PAPI. Nitroglycerin (1 μg/min/kg as a continuous infusion) de-creased the slope from 8.9±4.4 to 5.8±2.6 mmHg/L (p<0.05), again with no significant effect on PAPI. The results suggest that hypoxia and nitroglycerin. respectively, increased and decreased incremental pulmonary vascular resistance upstream to the site of pulmonary vascular closure.

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A case with alternans of repolarization wave without changes in QRS complex and torsades de pointes after recovering from cardiac surgery was described.

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A case of Takayasu's aortitis with severe bilateral coronary ostial stenosis is re-ported. A transaortic coronary endarterectomy was performed and sufficient patency was confirmed angiographically 9 years after the operation. This is the first report of late coronary angiography after a transaortic coronary ostial endarterectomy in Takayasu's aortitis. The efficacy of this procedure for coronary ostial stenosis in Takayasu's aortitis is emphasized.

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Using a high-frequency ultrasound intravascular imaging system we evaluated the intravascular echo image by comparing it with histological findings in 57 arterial segments of 17 autopsy cases. Moreover, in 8 dogs we estimated the arterial elastic property by observing the change of the arterial section accompanying a reduction of arterial pressure due to hemorrhage (H) or nifedipine infusion (N). The characteristics of the intravascular echograms were as follows: 1) In a normal artery the arterial wall consisted of the inner high echoic, the medial low echoic and the outer high echoic layers. 2) In an aged artery the fibrous thickened intima was seen as the low echo layer giving an echo about the same as that of the normal media, and the intensity of the echo from the degenerated media was lower than that of the normal media. 3) In atheroma the echo intensity of the elastic fiber-rich region was higher than that of the surrounding region, while the calcified region showed as a brighter echo with outer echo free space due to shadowing. We measured the arterial radius, area and circumferential length on the intravascular echo image and calculated the arterial wall tension-circumferential length and the pressure-arterial area relationships. By analysing each relation, we obtained the stiffness and compliance parameters, respectively. The stiffness parameter with N was lower than that with H[(1.5±0.5) × 10^-2 vs (2.8±0.9) × 10^-2] and the compliance parameter with N was higher than that with H (0.92±0.28 vs. 0.46±0.12). With these data obtained by analysing the intravascular echo image, we could indicate that the arterial wall stiffness de-creased and arterial compliance increased due to nifedipine infusion. We think that this new method could be used to evaluate the effects of various drugs on the elastic property.

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Intravascular ultrasound imaging is a new technique for visualizing arterial structures. The purpose of this study was twofold; first, to assess the ability of this intravascular ultrasound catheter to generate cross-sectional images of human artery segments in vitro and second, to determine the reliability of intravascular ultrasound technique in the evaluation of human arteries in vivo. For the vitro study, ultrasound images of the arteries were presented as a two-dimensional, 360° display of vessel cross-section perpendicular to the long-axis of the probe. The ultrasound scanning provided an accurate description with high resolution of lumen structure and lumen-intima interface in all vessel specimens. There was a good correlation between the planimetric luminal area on the ultrasound images and the area obtained from histologic images (r=0.92). There was also a good correlation in the plaque thickness between ultrasound and histological examination (r=0.88). In the in vivo study, the ultrasound catheter was easily introduced, readily manipulated, and images were successfully obtained in all patients, No untoward effects were noted during manipulation of the catheter. There was a good correlation in the arterial dimension between ultrasound and angiographic measurements (r=0.93). Thus, intravascular ultrasound imaging appears to be useful for characterizing and quantitating arterial lesions.

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To detemine the feasibility of intravascular ultrasound imaging in vivo, a miniaturized high frequency transducer catheter was introduced into human peripheral (n=10) and coronary (n=4) arteries. Cross-sectional ultrasound images were obtained from iliofemoral arteries in 10 patients using a 20 MHZ transducer catheter (1.2 mm in diameter) and from coronary arteries in 4 patients using a 30 MHZ transducer catheter 5 French size (Fr) following successful coronary angioplasty. Ultrasound images obtained from peripheral arteries showed a three-layered appearance (echo-reflective intima, echo-lucent media and echo-reflective adventitia) in the normal arteries. In diseased arteries, the location, amount and extent of atheromatous plaque were clearly documented. The arterial diameters measured by ultrasound closely correlated with the measurements by angiography (r=0.91) in the peripheral arteries. Coronary angiograms obtained following balloon angioplasty revealed smooth edges at the dilatation sites without significant narrowing in all patients. However, a significant amount of residual atheromatous plaque was clearly observed on the ultrasound images at the previously dilated sites. Coronary dissection, which was identified as an echo-lucent area behind the plaque, was noted in 2 patients. Ultrasound images also revealed the presence of calcium in the plaque which was unrecognized on the angiograms in 3 patients. In addition, direct measurement of the lumen cross-sectional area was possible on the ultrasound images. These results indicate that (1) the clinical use of intravascular ultrasound imaging catheters is feasible in human peripheral and coronary arteries in vivo, (2) both quantitative and qualitative assessments of atheromatous plaque are possible, and (3) this device will be useful for determining the quantitative and morphologic changes following coronary angioplasty.

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We have evaluated the feasibility of percutaneous transluminal coronary angioscopy for detecting intraluminal pathological changes as a diagnostic tool, and investigated the pathogenesis of two acute coronary disorders, acute myocardial infarction and unstable angina. Twelve patients with an acute coronary disorder and 20 patients who underwent percutaneous transluminal coronary angioplasty were selected for this comparison between the diagnostic accuracy of angios-copy and arteriography. One hundred and thirty patients were investigated by angioscopy as follows in order to investigate the pathogenesis of their acute coronary disorders: 22 with-in 8 h of onset acute myocardial infarction; 28 from one day to 2 months since onset recent myocardial infarction; 37 with an old myocardial infarction; 26 with unstable angina; and 23 with stable angina. Our results have indicated that thrombi were detected more frequently by angioscopy than by arteriography (p<0.01). Also, thrombi, intimal irregularities, and xanthomatous atheromas were observed more frequently in patients with acute myocardial infarction, recent myocardial infarction, and unstable angina. It is concluded that coronary angioscopy is a much more sensitive method for detecting intraluminal changes, and that a thrombus overlying a rupture in the lining of plaque plays a major role in an acute coronary disorders, and that the fragile, Iipid-rich gruel atheroma may precede its rupture.

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We assessed atherosclerotic lesions in the thoracic aorta in 166 consecutive patients (aged 56±13 years) by transesophageal echocardiography, and investigated the influences of hypertension, hypercholesterolemia and age on the prevalence of such lesions. Satisfactory images were obtained of all the thoracic aorta, except for a small part of the ascending aorta, by use of a biplane transesophageal probe. We defined atherosclerotic lesions as increased echogenicity of the intima (intimal thickening), raised plaque, calcification, ulceration, or aneurysms. Lesions were observed in 97 patients (58%). The incidence of lesions in patients with hypertension (81%) or hypercholesterolemia (80%) was significantly greater than in those without both conditions (37%, p<0.005). The incidence of lesions was significantly increased among patients over 60 years old compared with that in patients under 60 (76% vs 42%, p<0.005). Patients without either hypertension or hypercholesterolemia showed a marked in-crease in the incidence of lesions with age (16% at<60 yrs vs. 67% at >60 yrs), and no significant influence of these conditions on the incidence of lesions was found in patients over 60. We conclude that hypertension and hypercholesterolemia might be important risk factors for the development of atherosclerotic lesions in the thoracic aorta in relatively younger patients. Age appears to become a more important determinant of such lesions in Japanese patients over 60 years old irrespective of blood pressure and serum cholesterol levels.

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Thallium myocardial imaging has been widely available for the detection of myocardial ischemia and assessment of myocardial viability in coronary artery diseases. However, myocardial imaging using SPECT and gamma-emitting radiopharmaceuticals has been developed for accurate evaluation of myocardial infarction and sichemia. The present study was undertaken to clinically evaluate myocardial necrosis, metabolism and sympathetic nerve activity. In this study, myocardial fatty acid metabolism was assessed using ¹²³I-BMIPP, myocardial sympathetic neural activity was assessed using ¹²³I-MIBG and myocardial necrosis was assessed using ¹¹¹-In-antimyosin Fab. Dual energy SPECT using these new agents and thallium gives precise characterization of myocardial viability in coronary artery disease.

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Positron emission tomography (PET) using N-13 ammonia and F-18 fluorodeox-yglucose (FDG) has been used to evaluate myocardial viability in comparison with thallium-201 single photon emission computed tomography (SPECT), and left ventricular wall motion in comparison with contrast ventriculography. Forty patients with anterior myocardial infarction underwent stress and delayed resting perfusion imaging using T1-201 SPECT and ammonia PET, a glucose metabolism study using FDG PET, and wall motion assessment with left ventriculography. Out of a total of 600 segments of left ventricular imaging, SPECT demonstrated 197 fixed perfusion defects, 99 with redistribution on delayed imaging and 304 normal segments. Of 197 segments with fixed defects, 24 (12%) were normal and 71 (36%) ischemic according to PET criteria, Nineteen of 28 with infarction and all of 12 with non-Q wave infarction showed a viable myocardium. Left ventricular wall motion was significantly better in patients with normal PET findings compared with those with ischemia or scar on PET. Post-PTCA PET revealed improved ammonia PET in 6 of 11 patients but reduced FDG uptake was noted only in 3. These data suggests that T1-201 SPECT significantly underestimates myocardial viability and that PET imaging is a promising tool for assessing the presence of salvaged myocardium.

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To assess the usefulness of in vivo ³¹P nuclear magnetic resonance (NMR) spectroscopy, we investigated spectra from the myocardium in 6 patients with old Q-wave infarction (QMI), 6 with old non-Q-wave infarction (NQMI) and 9 con-trols by ECG-gated depth-resolved surface-coil spectroscopy. External hex-amethylphosphoric triamide (HMPT) was used to quantify the signal intensities. Left ventricular weight in the region of interest (LVW) was estimated from IH magnetic resonance images. The extent score by ²⁰¹T1 scintigraphy was deter-mined in 3 QMI and 4 NQMI patients. No significant differences were found among the 3 groups in peak area ratios of ³¹P NMR spectra to phosphocreatine (PCr) or adenosine triphosphate (ATP). Compared with controls, significant reductions were observed in values for the peak areas of PCr normalized by the standard HMPT (PCr/HMPT) or by both HMPT and LVW (PCr/HMPT/LVW) for QMI patients (p<0.05), and in ATP/HMPT and ATP/HMPT/LVW for QMI and NQMI patients (p<0.01). There was a significant negative correla-tion between ATP/HMPT and the ²⁰¹T1 scintigraphy extent score (p<0.05). These findings suggest that in vivo ³¹P NMR spectroscopy can detect high-energy phosphate reduction in the infarcted myocardium and may be useful in evaluating myocardial viability.

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Nuclear magnetic resonance spectroscopy (MRS) is a new technique for the evaluation of myocardial metabolism. Recently, localized MRS has been clinically available to measure by a non-invasive method the relative concentrations of the high-energy phosphate metabolites in the myocardium. We performed ECG gated P-31 MRS using ISIS (image-selected in vivo spectoroscopy) in 15 normal volunteers, 12 patients with hypertrophic cardiomyopathy, 12 with left ventricular hypertrophy. 6 with dilated cardiomyopathy and 11 with specific heart muscle disease. Myocardial peak height ratios of PCr/γ-ATP, Pi/γ-ATP and PCr/Pi were measured. Myocardial P-31 MRS demonstrated a significant decrease in the ratio PCr/ATP in patients with hypertrophic cardiomyopathy and specific heart muscle disease as compared with normal subjects, indicating myocardial metabolic disturbance in these patients. The ratio of PCr/ATP in patients with dilated cardiomyopathy did not differ significantly from that of normal subjects. However, exercise MRS revealed a marked decrease of PCr peak in an asymptomatic patient with dilated cardiomyopathy, which may indicate a latent metabolic disturbance in the myocardium of dilated cardiomyopathy.

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In this study we evaluated quantitatively the contrast enhancement of the myocardium of 27 patients with infarction and ischemia by ultrafast CT (Imatron C-100) with a scan time of 100 msec. We defined three parameters from the CT numbers of the myocardium and the ventricle in both the early and the late phase (about 4 min) after the injection of non-ionic contrast material; the difference of the CT numbers of myocardium between the early and the late phase (ΔCT# ), and the ratios of the CT numbers of the myocardium and the ventricular lumen (M/L) in both the early phase and the late phase. The ΔCT# for myocardial infarction and severe ischemia were -20±10HU and -8±10HU, respectively. These values were significantly lower than the mild ischemic myocardium and normal myocardium (p<0.001). The average M/L values for myocardial infarction and ischemia in the early phase were 19±8% and 16±6%, respectively. These values were significantly lower than those in normal myocardium (p<0.001). The average M/L values for infarction and severe ischemia in the late phase were 90±18% and 63±20%, respectively. These M/L were significantly dissociated (p<0.001). Our results indicate that with contrast UFCT it is feasible to detect quantitatively the myocardial characteristics of ischemia and infarction.

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Cardiac cine magnetic resonance imaging (MRI) was studied to evaluated the cardiac motion and function, and a water-stream phantom study was performed to clarify whether it was possible to quantitatively assess the valvular regurgitation flow by the size of the flow void. In normal subjects, the left ventricular (LV) epicardial apex swung up to the base only a few millimeters, and the mitral annulus ring moved about 14 mm as mean value toward the apex during systole. Those motions of mitral annulus ring may contribute to the left atrial filling. The LV longitudinal shortening and torsions were shown by the tagging method. This tagging method was the best method for estimating cardiac motions. Cardiac cine MRI using software including a modified Simpson's method program and a wall motion analysis program was useful for routine LV volumetry and wall motion analysis because it was a simple and reliable method. Our water-stream phantom studies demonstrated that it might be difficult to perform quantitative evaluation of valvular regurgitation flow by using only the size of the flow void without acquiring in-formation relating to the orifice area.

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