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BACKGROUND: Myocardial infarction is the result of acute thrombotic occlusion of a coronary artery, most likely secondary to rupture of an atherosclerotic plaque. Intracoronary ultrasonic (ICUS) examinations were performed in patients with acute myocardial infarction (AMI) in order to describe intraluminal ultrasonic findings at the site of acute coronary occlusion. METHODS: Coronary angiography and ICUS studies were performed consecutively within 6 h of the onset of chest pain in 30 patients with AMI prior to percutaneous transluminal coronary angioplasty (PTCA). The control group consisted of 30 patients with chronic stable angina pectoris (SAP). Following angiographic documentation of a proximal stenosis or occlusion, a 3.5 or 4.8 F mechanical ultrasound catheter (20 MHz) was advanced successfully through the lesion in 25 of 30 (83%) patients with AMI and in 15 of 30 (50%) patients with SAP (P < 0.01). RESULTS: Intracoronary ultrasound permitted differentiation between pulsatile, low-echogenic intraluminal material suggesting thrombus and mural highly echogenic atherosclerotic plaque in 22 of 25 (88%) patients with AMI. A negative imprint of the ICUS catheter was documented within the low-echogenic material in 17 of 25 (68%) patients with AMI. Low-echogenic intraluminal material was found in 18 of 25 (72%) segments proximal and in 12 of 25 (48%) segments distal to the highly echogenic plaque, indicating prestenotic and post-stenotic thrombus in AMI. The plaque appeared eccentric in 22 of 25 (88%) patients with AMI. In comparison, stenotic lesions in chronic SAP patients were less frequently eccentric (5/15, 33%, P < 0.01) and contained a higher proportion of pure highly echogenic material (12/15, 80%). Cross-sectional area stenosis due to highly echogenic plaque averaged 52 +/- 13% in AMI and 82 +/- 3% in SAP (P < 0.01). Calcification of plaque was evident in 21 of 25 patients with AMI (SAP 12/15, 80%, NS). The surface of the plaque was rough in 13 of 25 (52%) AMI patients (SAP 4/15, 27%, P < 0.05). Fissures were detected in only seven (28%) patients and dissection was observed in two (8%) cases. The low incidence might be a result of the limited resolution of the ICUS system. CONCLUSION: This study demonstrates that ICUS with 4.8 or 3.5 F catheters is feasible and safe in selected patients with AMI, and adds little to the overall duration of the angioplasty procedure. The identification and demarcation of atherosclerotic plaque provided by ICUS could prove valuable in guiding PTCA, in deciding on appropriate therapy, and in acute and long-term follow-up of AMI patients.

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Stress echocardiography has recently gained increased importance as a method for assessment of left ventricular function. However, suboptimal image quality in some patients may limit use of this technique. In the present study, 10 patients with moderate image quality in the resting echocardiograms (apical 4-chamberview) were reinvestigated after administration of the intravenous transpulmonary saccharide-based left heart contrast agent SHU 508 A. Duration of contrast enhancement in the left ventricle determined by visual assessment was 135 s (SEE +/- 39) at rest and 112 s (+/- 24) during maximum exercise. On a scale ranging from O (no contrast) to 4 (excessively strong contrast) enhancement averaged 2.5 at rest and during exercise. The left ventricle was divided into three segments (septum, apex, lateral wall) and delineation of the endocardial border was assessed. Detection of the border improved significantly after contrast administration, especially at the lateral wall. Despite better visual assessment of the endocardial border, there was no improvement in automatic or semi-automatic contour recognition. No clinically significant side-effects were observed. Three patients reported a sensation of warmth at the injection site. In conclusion, intravenous administration of SHU 508 A improves visual detection of the left ventricular endocardial border in patients with suboptimal image quality and helps to achieve acceptable diagnostic accuracy with stress echocardiography in these patients.

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Thirteen patients with aortic aneurysm (abdominal 7, thoracic 4, thoraco-abdominal 2) were evaluated by magnetic resonance tomography using a super-conducting magnet of a field strength of 0.35 tesla in transversal, coronal and sagittal planes. ECG gating was used in patients with thoracic aneurysm. The results of magnetic resonance imaging (MRI) were compared to angiography, computed tomography (CT) and intraoperative findings. MRI demonstrated in all 13 patients the extent and the localisation of the aneurysm. The presence of mural thrombus was better determined by MRI (10/10) than by angiography (6/10). The relationship of the brachiocephalic arteries in thoracic aneurysm was better evaluated by MRI compared to angiography and CT. All 3 aortic dissections could be demonstrated by MRI. These first results may suggest an important role of MRI in the diagnosis of aortic aneurysms.

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Gated magnetic resonance tomography (MRT) was conducted in 40 patients (13 normal volunteers, 9 hypertensives and 18 patients with hypertrophic cardiomyopathy) using a 0.35 Tesla superconducting magnet. Multisectional spin echo imaging (35/400 msec) was obtained in coronal, transversal and sagittal planes. Myocardial wall thickness was measured in different segments and the three groups were compared to each other. 15/18 patients with hypertrophic cardiomyopathy (HCM) had asymmetrical regional thickening involving the septum and the anterior wall, in 8/15 the lateral wall was also hypertrophic. The distribution pattern in 3/15 patients with HCM was symmetric. Involvement of the right ventricle was found in 14/18 patients with HCM. There were significant differences (p less than 0.001) in wall thickness for the septal segment in all three groups and for the ratio septal to posterior wall between the HCM and the hypertensives and the normal volunteers. We conclude that MRT can differentiate HCM from hypertensives and normals, and is superior to echocardiographic imaging in the evaluation of the distribution of left ventricular hypertrophy in hypertrophic cardiomyopathy.

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The validity of two-dimensional echocardiography (2 DE) in the diagnosis of evolving myocardial infarction was assessed in 123 patients with a suspected acute myocardial infarction (chest pain for less than 4 hours). 84 patients developed a myocardial infarction, 39 did not. Detection and extent of a regional wall motion disorder in 2 DE were compared to ECG, enzymes, hemodynamics, coronary angiography and clinical data. The reliability of ECG and 2 DE in the diagnosis of acute myocardial infarction was found to be similar: sensitivity 89% for 2 DE, 96% for ECG; specificity 89% vs (= versus) 73%; positive predictive value 95% vs 89%; negative predictive value 79% vs 90%. This means that in most cases the ECG is a sufficient and reliable method in detecting or excluding acute myocardial infarction. Because of the equipment needed, the limited practicability and because of specific problems (distinction between new and old infarction), the 2 DE should be regarded as a supporting method to the ECG but not as an essential one in the diagnosis of acute myocardial infarction. The possible benefit of echocardiographic examination is the identification of high risk patients by non-invasive determination of the size of infarction. There was a significant correlation between the extent of wall motion disorder and the maximum CK levels as well as the incidence of cardiac complications such as hypotension, pulmonary congestion, and ventricular arrhythmias.

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127 patients with diagnosis of acquired mitral and aortic valve disease confirmed by cardiac catheterization were followed for 5-17 years (mean 10 years) under conservative management. At the end of the study, 80 patients were still alive, and 68 of them were examined again. 23 patients died, and no information was available on 24. Analysis of the natural course of the disease showed that results obtained with different classification systems (NYHA, clinical findings, hemodynamic data) were not comparable. However, the majority of mitral and combined mitral-aortic lesions remained stable over the years, independent on the initial classification of the lesion. Aortic valve disease became hemodynamically worse in the absence of subjective and clinical change.

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Prosthetic valve replacement was performed in 113 patients above the age of 60 with advanced valvular heart disease, whose prognosis without surgical correction was extremely poor. Although there was high risk of early mortality in isolated aortic valve disease (20%), in isolated mitral valve disease (28%) and in multiple valve disease (50%), improvement for the survivors was evident. Late mortality was rather low. Individual risk can be estimated by considering the patient's age, type and stage of valvular disease as well as the clinical condition and hemodynamic parameters.

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The value of prosthetic valve replacement is determined not only by the improvement in life expectancy but also by the quality of life. This statement resulted from an analysis of 168 patients undergoing isolated aortic -- or mitral -- valve replacement between 1970 and 1976. Besides numerous complications -- probably often avoidable such as side effects of incorrect anticoagulation -- long term results of 125 surviving patients were satisfactory over a period of 3-9 years after surgery. Though complete restitution was rare, subjective and objective improvement -- different and dependent on type and degree of valve disease -- was persisting and the effect on social and professional incorporation surprisingly positive.

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We report about a dialysis procedure, the circulation stability of which is comparable to hemofiltration treatment. Hemodynamic parameters were measured invasively and different procedures were compared for each patient. In RD and HF significant reduction in cardiac output (HF: --20%, RD: --21.5%), stroke volume (HF: --20%, RD: --17%), pulmonary artery pressure (HF: --57%, RD: --45:6%) and plasma volume (HF: --12%, RD: --15%) were found. Blood pressure and heart rate (HF: --1%, RD: --3%) remained stable despite the high utrafiltration rate. Peripheral resistance rose significantly (HF: + 20%, RD: + 25.9%). Compared with HG, the most important advantage during RD is the improved tolerance to treatment without typical hemodialysis-induced symptoms. In comparison to that, we found under conventional dialysis an inadequate increase in peripheral resistance (HD: + 6.1%). A following strong compensatory hyperventilation with drop in PCO2 was paralleled with typical symptoms like nausea and headache. Because of resttriction of this compensatory mechanism, hypotension and arrhythmia will be induced of the following peripheral tissue perfusion and central acidosis.

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A study was undertaken to evaluate the acute hemodynamic effects in ten patients from this clinic's long-term peritoneal dialysis program. With a Swan-Ganz catheter, the following parameters were measured in each patient during peritoneal dialysis: cardiac index, pulmonary artery pressure, right atrial pressure, inferior vena cava pressure, heart rate and arterial pressure. Mean predialysis cardiac index, stroke volume index and heart rate were normal. Predialysis pulmonary artery pressure and arterial pressure were slightly elevated. Mean weight loss during peritoneal dialysis was 1.6 kg. The most striking post-dialysis changes were a significant 20% decrease of the cardiac index and a 17% decrease of the pulmonary artery pressure. Heart rate and arterial pressure remained constant due to a 25% increase of total peripheral resistance. After filling the abdomen with one, two and three liters of dialysate, intra-abdominal pressure and inferior vena cava pressure increased up to 150 and 100%, respectively, whereas central hemodynamic parameters (pulmonary artery pressure, cardiac index, stroke volume index, heart rate and arterial pressure) were unchanged.

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Circulatory parameters were determined by cardiac catheterization in patients on maintenance hemodialysis. They were studied in three groups during conventional hemodialysis, sequential ultrafiltration and hemofiltration. All three groups revealed significant reduction of cardiac output, stroke volume, pulmonary artery pressure and plasma volume. In the hemodialysis group hemodynamic parameters were unstable; specifically, hypotension, increased heart rate, and only minimal increase of peripheral resistance were observed. The other two groups showed only minor changes in circulatory parameters despite high ultrafiltration rates. Blood pressure and heart rate remained stable. On the other hand, peripheral vascular resistance increased remarkably. There is compelling evidence that during hemofiltration and sequential ultrafiltration, the patient's ability for vasoconstrictive counterregulation is better maintained than during conventional hemodialysis.

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In 17 patients with peripheral arterial occlusive disease the influence of intra-veinously applicated Bencyclane (Fludilat) on cardiac output and central-hemodynamic parameter has been investigated. While 100 mg (n = 8) of Bencyclane almost do not influence cardiac output, 200 mg (n = 9) cause a significant decrease of minute-volume of the heart by-17.22% and of heartfrequency by-8.85%. With either dose there is also a significant increase of aortic pressure, pulmonary arterial pressure and pulmonary vessel resistance to be seen. These results correlate with the animal-experimental proof of a negative inotropy under Bencyclane, and they have to be considered in therapeutical use.

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Three patients on maintenance dialysis were each treated with three different procedures: A) twenty-liter recirculation dialysis with bicarbonate buffering, B) recirculation-adsorption dialysis and C) single-pass dialysis. Hemodynamic parameters were measured invasively and procedures A, B and C were compared for each patient. In this intraindividual comparative study, the authors attempted to establish a relationship between the varying hemodynamic parameters and the changes in osmolality and acid-base status. There were indications of some causal relationship to circulatory stability: in A and B, there were peripheral resistance increases of 24.5% and 38.4%, respectively, with stable circulation; in C, there was a 6.1% increase and unstable circulation. Additionally, the influence of acidosis is shown in B, with disproportionately strong reductions of cardiac output (21.9%) and pulmonary artery pressure (44.9%); In spite of a decrease of osmolality (A: 15.6 mOsm/L), stable circulation could be achieved if the peripheral resistance was substantially increased and acid-base status was equalized.

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The natural history of congenital heart disease in older patients will become increasingly difficult to delineate, since many of uncomplicated defects were repaired early in life. Therefore the frequency of clinical and hemodynamic progress in non-operated patients with atrial septal defects seems to be of great interest. We are able to compare 27 patients aged more than 60 years with a group between 40 and 59 years. In 80 out of 103 patients totally, the clinical findings could be completed with catheterization data. The progress of deterioration with age in spite of intensive medical care could be demonstrated by mostly statistical significant signs of greater right-ventricular overload in the Ecg, cardiac arrhythmias--usually atrial fibrillation--changes in the X-ray findings and increasing pulmonary hypertension.

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In eight lung autotransplants and six normal lungs the vasomotor activity was tested with norepinephrine and acetylcholine. In autotransplants and normal lungs both substances elicit the same effects. The long-term interruption of the central innervation does not provoke a vasoconstriction in lung autotransplants.

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An arteriovenous aneurysm of the fifth intercostal artery on the left, communicating with the left subclavian vein, is described. This has not been observed previously. It occurred in a 50-year old woman with multiple arterial aneurysms and stenosing aortic sclerosis.

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