[Fatty acid metabolic disorder detected by 123I-BMIPP SPECT shortly after elective percutaneous transluminal coronary angioplasty].

UNLABELLED: Decreased or unchanged BMIPP uptake is often observed in the repeated SPECT imaging soon after successful angioplasty, although coronary flow remarkably recovers. To evaluate clinical significance of this phenomenon, 23 patients underwent BMIPP SPECT before elective PTCA (BM-1), soon after PTCA (72 hours, BM-2), and 3 months later (BM-3). SPECT imagings were divided into 7 segments and were semiquantitatively evaluated by 2 cardiologists in the blinded fashion. Decreased uptake at BM-2 compared with BM-1 was evaluated by comparing with stress Thallium-201 SPECT performed in the same schedule but on the different date (TI-1, 2, 3), ischemic manifestation at PTCA, and wall motion change of LVG. Patients with restenosis were excluded from this study. RESULTS: BM-2 showed decreased uptake in 14 (61%), unchanged in 2 (9%), and increased in 7 (30%) patients, while stress TI showed increased perfusion in all patients. Among 91 myocardial segments correspondent to PTCA vessels, 30 (33%) showed overt uptake reduction, and only 13 (14%) segments showed increased uptake. BM-2 uptake reduction was significantly associated with the absence of collateral artery (odds ratio, OR = 3.1, p <0.01), multi vessel disease (OR = 2.0, p = 0.01), total balloon inflating time (p <0.05), ST elevation on ECG (OR = 3.6, p = 0.01), chest pain during PTCA (OR = 3.1, p <0.1), while pre-dilatation by using small size balloon catheter prevented BM-2 uptake reduction (OR = 6.0, p = 0.01). Multiple logistic regression analysis showed that chest pain, balloon inflating time and pre-dilatation were independently associated with BM-2 uptake reduction. Three months after PTCA. the segments with BM-2 reduction had stress TI uptake similar to the segments without BM-2 reduction, however, they showed poorer recovery of BM-3 uptake and LV wall motion. CONCLUSION: BMIPP uptake reduction shortly after angioplasty was associated with ischemic manifestation and poor LV motion recovery, thus, it may be a sensitive representation of the stunned myocardium.

[Relationship between static images of 13N ammonia positron emission tomography and left ventricular wall motion in patients with coronary artery disease].

Observed myocardial activities in static image of 13N ammonia positron emission tomography (PET) contains factors about not only myocardial blood flow but also wall motion, wall thickness and glutamine synthetase activity. Those factors may help to delineate myocardial viability in 13N ammonia static image. To assess the role of 13N ammonia static image in prediction of reversibility of regional wall motion abnormalities after revascularization, we studied 20 patients with coronary artery disease. Of these patients, 15 patients underwent successful coronary revascularization (8 PTCA, 7 CABG). Regional 13N concentration before revascularization was expressed as a percent of maximal myocardial concentration and compared with regional wall motion. Wall motion was assessed by visual analysis using left ventriculography. Regional myocardial 13N concentration in normal, hypokinetic, akinetic and dyskinetic segments was 85 +/- 9.3%, 75 +/- 11%*, 71 +/- 17%* and 58 +/- 7.7%*#+, respectively (*p < 0.05 vs. normal, #p < 0.05 vs. hypokinesis, +p < 0.05 vs. akinesis). The segments with functional improvement showed significantly higher concentration of 13N than those without functional recovery (80 +/- 9.7% vs. 67 +/- 8.3%, p < 0.05). By using an optimized threshold value for normalized 13N activities, the sensitivity and specificity reached to 67% and 100%, respectively, to predict functional recovery. Our data suggested that myocardial 13N concentration in static PET image is closely related to the left ventricular wall motion in the patients with coronary artery disease and that it has a possible value of prediction of myocardial viability.

[Clinical experience of the Greenfield filter--especially about tilting and distal migration of the filters].

Since December 1985, we used Greenfield filter in 8 patients to prevent pulmonary embolism. Mean follow-up period was 42 month. Recurrence of pulmonary embolism was suspected in one patient after perfusion lung scan. Another patient died from other reasons. Occlusion of the inferior vena cava was not suspected in any patient clinically. Tilting and distal migration of the filters occurred frequently. 3 filters tilted greater than 5 degrees compared with the position immediately after their placement. 5 filters migrated distally more than half the length of a lumbar vertebra. Although there was no severe complications in our series, we should pay attention especially to the position and angle of the filters, since an extreme tilting position of the filter could be a possible cause of serious complications.

Comparison of coronary hemodynamics in patients with internal mammary artery and saphenous vein coronary artery bypass grafts: a noninvasive approach using combined two-dimensional and Doppler echocardiography.

Blood flow in bypass grafts and recipient left anterior descending coronary arteries was evaluated with combined two-dimensional and Doppler echocardiography in 15 patients with an internal mammary artery graft and in 24 patients with a saphenous vein graft. Comparative studies of coronary hemodynamics were also performed regarding these two different grafting techniques. The graft vessel was detected in 11 (79%) of 14 patients with an internal mammary artery graft and in 20 (87%) of 23 with a saphenous vein graft. The recipient left anterior descending coronary artery was detected in 10 (67%) of the former group and 17 (71%) of the latter. The blood flow patterns obtained were generally biphasic, consisting of systolic and diastolic phases with higher velocity during diastole. The maximal diastolic flow velocity in internal mammary artery grafts was much higher than that in saphenous vein grafts. In patients with an internal mammary artery graft, the flow pattern characteristics within the recipient coronary artery were quite similar to those within the arterial graft, and flow velocities within the recipient coronary artery and the arterial graft were quantitatively almost identical. This outcome may contribute to the long-term patency seen in internal mammary artery grafts. On the other hand, the flow velocity in saphenous vein grafts was fairly low throughout the cardiac cycle. Flow velocity in the recipient coronary artery in patients with a saphenous vein graft was accelerated only in early diastole. As a result, the recipient coronary artery flow pattern and velocity differed substantially from those in the saphenous vein graft.(ABSTRACT TRUNCATED AT 250 WORDS)

Noninvasive measurement of coronary artery blood flow using combined two-dimensional and Doppler echocardiography.

Noninvasive measurement of left anterior descending coronary artery flow was attempted in 20 normal subjects and 80 patients with cardiovascular disease (valvular heart disease in 34, ischemic heart disease in 26, cardiomyopathy in 15 and other diseases in 5) using combined two-dimensional and Doppler echocardiography. A tubular structure about 2 mm in diameter containing Doppler flow signals was identified in the anterior interventricular sulcus in 7 (35%) of the normal subjects and 40 (50%) of the patients with cardiovascular disease. The blood flow within the tubular structure exhibited a biphasic flow pattern, consisting of systolic and diastolic phases with higher velocity during diastole. The highest velocities were observed in early diastole and, in several cases, a small peak was detected during the atrial contraction phase. On the basis of its spatial orientation and characteristic flow pattern, the tubular structure was identified as the midportion of the left anterior descending coronary artery. In a number of cases it was difficult to detect the systolic blood flow. Although blood flow was normally directed from the cardiac base to the apex, it was reversed toward the base in the patients with a bypass graft to the left anterior descending coronary artery. In patients with severe aortic insufficiency, however, flow velocity was lower during diastole than during systole and the duration of diastolic flow was reduced, failing to continue to the end of diastole. Flow velocity was high in patients with a bypass graft to the left anterior descending coronary artery, aortic stenosis or hypertrophic cardiomyopathy.(ABSTRACT TRUNCATED AT 250 WORDS)

[Noninvasive measurement of cardiac output using two-dimensional Doppler echocardiography and analysis of sources of error].

The purpose of this study was (1) to analyze the factors responsible for errors in the two-dimensional Doppler echographic measurements of cardiac output (C.O.) and (2) to establish a noninvasive method for measuring C.O. The subjects were 50 cardiac patients who had neither aortic valve disease nor intracardiac shunts. The C.O. was calculated using the following formula: C.O. (l/min) = mean flow velocity (cm/sec) x pi(aortic ring diameter/2)2 (cm2) x 60/10(3) Left ventricular ejection flow velocity was recorded in the center of the aortic ring from the apical approach. Mean velocity was calculated by integration of instantaneous mean velocity in the ejection phase divided by the cardiac cycle length, and was corrected by the Doppler incident angle. The inner diameter of the aortic ring was measured in the parasternal long-axis view at the time of the maximum ejection flow velocity. The following results were obtained: 1. Sources of error in the measurement of cardiac output. 1) Accuracy of instantaneous mean velocity calculating circuit: This calculating circuit was accurate in model experiments using pulsatile flow. 2) Effect of high-pass filter: In model circuits, application of high-pass filter overestimated flow velocity. The higher the cut-off frequency of the high-pass filter, the larger the overestimation. This was probably due to the parabolic flow velocity profile in the circuit. 3) Flow velocity profile in the aortic ring: The flow velocity profile seemed to be flat in the aortic ring except near the anterior aortic wall. Therefore, the effect of the high-pass filter was considered to be negligible in case of clinical application. 4) The effects of shift and size of sample volume: The location of sample volume relative to the aortic valve ring shifted about 7 mm during systole. However, the shift and size of sample volume seemed to have little effect on the measured C.O., because the flow velocity profile was nearly flat in the aortic ring. 5) Ultrasound beam incident angle: From a practical viewpoint, it was necessary to set an incident angle of less than 50 degrees for minimizing the error. We were able to set the angle within 50 degrees in all but one of patients. 6) Diameter of the aortic ring: Two-dimensional echographic measurement of the aortic ring diameter was not so accurate; it seemed to become a major source of error in the calculation of C.O.(ABSTRACT TRUNCATED AT 400 WORDS)

Doppler echocardiographic features of ventricular septal rupture in myocardial infarction.

Doppler echocardiography was used to evaluate the features of interventricular septal rupture in six patients with acute myocardial infarction and to substantiate the hemodynamic data and morphologic findings at surgery or autopsy. Although echocardiographic visualization of the septal rupture was obtained in only two of the six patients, unusual Doppler flow signals were detected in the apical portion of the right ventricle in all six patients. Five patients had unusual flow signals during both systole and diastole; one had such signals only during systole. The location of these unusual flow signals coincided with the site of septal rupture confirmed at surgery or autopsy. The pattern of the flow signals in one cardiac cycle was very similar to that of the pressure difference between the left and right ventricular cavities. These findings indicate that the unusual flow signals represent the left to right shunt flows resulting from septal rupture. In conclusion, Doppler echocardiography may be a very useful tool for diagnosing interventricular septal rupture easily and noninvasively in patients with acute myocardial infarction.

[Aortic flow patterns in heart diseases with left-to-right shunts from the aorta, and their clinical significance: a Doppler echocardiographic study].

Aortic flow patterns were analyzed using two-dimensional Doppler echocardiography for 15 patients with patent ductus arteriosus, seven with ruptured aneurysms of the sinus of Valsalva, two with coronary artery fistulae and for 22 healthy persons, with special reference to diastolic flow patterns. The conclusions were as follows: In healthy subjects, there was a tiny and transient reversed flow signal in early diastole followed by a slow and sustained diastolic forward flow signal. The velocity of the diastolic forward flow was slower and the duration was shorter in the lower abdominal aorta than in the upper portion. In patients with shunts from the aorta to the right-sided chambers, the early diastolic reverse flow was enhanced, and another reversed flow developed in mid- and late diastole, which was the most evident in the lower portion of the abdominal aorta. The extent of the reversed flow correlated significantly with Qp/Qs by catheterization (r = 0.73). Thus, the abdominal flow patterns in cases with left to right shunts from the aorta to the right-sided chambers of the heart provided information for estimating the size of the shunt volume. In patients with bi-directional shunts, the dominant direction of the shunt during diastole can apparently be determined by analyzing the aortic flow patterns.

[Noninvasive determination of the ratio of pulmonary to systemic blood flow with two-dimensional Doppler echocardiography: efficacy and limitation].

Noninvasive determination of the ratio of the pulmonary to systemic blood flow (Qp/Qs) was attempted in 31 cases with intracardiac shunt using two-dimensional pulsed Doppler echocardiography. The Qp/Qs of these cases was ranged from 0.99 to 4.55 with an average of 2.63 by cardiac catheterization. Technical problems in the measurement were also studied. Seventeen cases with no shunt were served as controls. Systemic and pulmonary flow volumes, Qp and Qs (ml/min), were calculated by the following equation: Q (ml/min) = mean flow velocity (cm/sec) X cross sectional area of the semilunar valve ring (cm2) X 60 Here, the sample volume was set in the center of the valve ring at the phase when the flow velocity attained its peak in a pulse period. The mean velocity was obtained by dividing the integration of instantaneous mean frequency in the sample volume for a pulse period by RR interval. The ultrasonic incident angle was measured on the echocardiogram. The velocity profile at the valve ring was assumed to be a plane wave. The diameter (D) of the valve ring was measured on the echocardiograms of the long-axis view of the outflow tract. To make a correction referring to the value obtained by angiocardiography, 0.22 cm was added to the value obtained on the echocardiogram (D). The cross sectional area of the valve ring was calculated according to the following formula: Cross sectional area (cm2) = pi X [(D + 0.22/2)]2 The Qp/Qs ratio by the Doppler method in the cases with no intracardiac shunt was 1.11 (S.D. = 0.21) on an average and the Qp/Qs in the cases with an intracardiac shunt was well correlated with that by catheterization (r = 0.82). These results suggested the feasibility of the clinical application of the Doppler method for noninvasive determination of Qp/Qs. In 17 cases, pulmonary and systemic flow volumes measured by the direct Fick method were compared with those by the Doppler method, respectively. Considerable differences were observed between them. There was a tendency that both pulmonary and systemic flow volumes were under-estimated by the Doppler method in cases with a large shunt.(ABSTRACT TRUNCATED AT 400 WORDS)

Doppler echocardiographic features of coronary arteriovenous fistula. Complementary roles of cross sectional echocardiography and the Doppler technique.

The Doppler echocardiographic features of coronary arteriovenous fistula were investigated in eight patients with left or right coronary arteriovenous fistulas who had a continuous heart murmur in the upper precordial area and whose diagnoses were confirmed by coronary angiography. In four patients the dilated lumen of the coronary arteriovenous fistula was visualised by cross sectional echocardiography. Of these, three showed abnormal unidirectional continuous flow signals with broad velocity spectra in the fistula. Abnormal, powerful, unidirectional or bidirectional continuous Doppler signals were detected in part of the pulmonary artery in two of the eight patients, in part of the right ventricle in two, and in part of the right atrium in one; these signals were interpreted as indicating shunt flow. Although the opening of the fistula was difficult to visualise by cross sectional echocardiography, the pulsed Doppler technique helped identify the site in patients with dilatation of the coronary artery. In the remaining three patients with a small shunt no abnormal findings were obtained with cross sectional echocardiography or the Doppler technique. The size of the fistula below which no abnormal findings may be obtained by Doppler echocardiography still needs to be determined.