Search PubMed⌕ Search

Biomedical subjects

H Kreuzer

Publications and source records attributed to H Kreuzer.

At least 307 records · Page 17Linked to original sources
PubMed1979

[Removal of an acute occluding coronary thrombosis by means of a Sones-catheter (author's transl)].

In a 60-year-old male patient thrombotic occlusion of a dominant right coronary artery was recanalized by means of a Sones-Catheter (8F) two hours after the clinical onset of myocardial infarction. Before recanalization the inferior wall of the left ventricle was akinetic. After recanalization this akinesia and the clinical symptoms of myocardial infarction was almost completely relieved. As evidenced by ECG and enzymes there was only a minor necrosis of the inferior wall. After one week ventricular function angiographically was completely normal. In the right coronary artery there was a 50 percent proximal stenosis, thrombi were completely abolished. Possible implications of this case are discussed.

Acute Disease↗
PubMed1979

[The determination of the left ventrical volume curve without background correction and its validation by direct intercomparison with the ejection fractions as determined by biplane laevocardiography (author's transl)].

Background corrections applied on the left ventricular volume curve determined by the "gated blood pool"--method are based on an estimated rather than on a directly measured background. This imposes an uncertainty on the values determined from the volume curve, especially on the ejection fraction. A method which does not require background correction may be applied if all available measurement and evaluation facilities are utilized fully. High temporal and spatial resolution is of fundamental importance, permitting the exact determination of the time-dependent scintigraphic contour variations of the left ventricle during the mechanical action of the heart. A good criterion of the validity of the volume curves with respect to interfering background radiation is the ejection fraction calculated from these curves. The direct intercomparison of 10 ejection fractions obtained by an expanded "gated blood pool"-method, employing cardiac catheterization, immediately before a biplane laevocardiography demonstrated very good agreement. A small systematic underestimation of the ejection fraction by the nuclear method was observed. This understimulation shows that the influence of the true background is small if other interfering count rate contributions or methodical uncertainties are excluded systematically.

Angiography↗
PubMed1979

[Quantitative exercise scintigraphy of the myocardium with 201Tl--methods and normal values (author's transl)].

Quantitative myocardial scintigraphy was performed in 20 normal individuals after maximum exercise and after two hours of rest. A mobile Anger camera with converging collimator and a Data-General computer with a 128 x 128 matrix were used. Quantitative analysis of data was performed on the basis of a 14-halfsegment model. Quantitative normal values after exercise and after redistribution of activity during rest are presented.

Adult↗
PubMed1979

[Left ventricular diastolic pressure-volume relations during exercise (author's transl)].

UNLABELLED: Left ventricular diastolic pressure-volume relations (PVR) were analysed from biplane ventriculograms and simultaneous pressure measurements in 33 patients at rest (R) and during ergometer exercise (E) (8 normals [N], 8 patients with coronary artery disease [CAD], 8 patients with congestive cardiomyopathy [COCM], 5 patients with aortic insufficiency [AI] and 5 patients with pressure overload (4 with aortic stenosis [A-St.] and 1 coarctation of the aorta). In N and AI diastolic PVR was essentially unchanged with E, the time constant of isovolumic relaxation (T) decreased significantly (N: delta T = -24.4 +/- 11.6%, p less than 0.001; AI: delta T = -27.3 +/- 6.8%, p less than 0.005). In CAD diastolic PVR was shifted upwards in all cases with angina pectoris during E (7/8), minimal rate of left ventricular pressure change (dp/dtmin) and T did not change significantly. In COCM diastolic PVR was shifted upwards in 4 cases, while dp/dtmin increased significantly (R = -1107 +/- 327, E = -1508 +/- 626 mm Hg-s-1, p less than 0.05), T on the average was unchanged (R = 53 +/- 10.5, E = 51 +/- 14.2 msec). In A-St. in 3 of 4 cases diastolic PVR was significantly shifted upwards with E, dp/dtmin increased (R = -1633 +/- 93, E = -2093 +/- 170 mm Hg-s-1, p less than 0.001), T in contrast to N and AI was prolonged (R = 33.8 +/- 4, E = 39.9 +/- 1.9 msec). CONCLUSION: In N and AI diastolic ventricular function is not altered with exercise. In COCM and especially in A-St., however, there are similar alterations like in CAD with angina pectoris. Changes in T indicate that shifts of the PVR with exercise in non-ischemic heart disease are related to a disturbed ventricular relaxation.

Adolescent↗
PubMed1979

[Echocardiographic dimensions of the left ventricle during ergometric exercise: results in normal subjects (author's transl)].

10 healthy men aged 18 to 32 years underwent M-mode-echocardiographic studies at rest, during exercise and recovery. Semisupine bicycle exercise was performed using work loads of 25, 50, 75, and 100 W with measurements taken every minute. With increasing exercise, heart rate rose significantly (p less than 0.01) from 68/min to a maximum of 132/min, blood pressure as obtained by sphygmomanometry rose from a mean of 83 torr to 102 torr. Left ventricular enddiastolic dimension (EDD) did not change significantly with exercise, left ventricular endsystolic dimension (ESD) decreased from a group mean of 34.8 mm to 30.5 mm. This paralleled an increase in stroke dimension from 18.3 to 22.6 mm and of fractional shortening (FS) from 0.34 to 0.43. Mean velocity of circumferential fiber shortening (MVCF) rose from 1.01 circ/s to 2.06 circ/s. During recovery, heart rate and blood pressure returned faster to resting levels than did ESD, FS, and MVCF. Again EDD did not change. These data indicate that heart rate contributes more to the increases in cardiac output observed with ergometric exercise than does stroke volume; with moderate exercise levels this increase in stroke volume is produced by diminishing endsystolic volume whilst enddiastolic volume remains unchanged.

Adolescent↗
PubMed1978

Haemodynamic effects of molsidomin.

Hemodynamic changes for 30 min after intravenous administration of molsidomin 4 mg were studied in 10 patients. Pulmonary artery pressure, pulmonary wedge pressure, right atrial pressure and aortic pressure decreased significantly after 15 min, and after 30 min they were still below the control level. Heart rate increased significantly (by 15%) 15 min after injection, and after 30 min it was still 8% above the control value. Cardiac index decreased significantly from 3.37 +/- 0.12 to 2.95 +/- 0.15 1/min/m2. Peripheral and pulmonary resistance showed no significant change. Both stroke work index and minute work decreased significantly 15 min after administration of molsidomin and after 30 min both were still below the control level. The results suggest that molsidomin decreases preload without influencing afterload. By decreasing preload, molsidomin improves the oxygen supply/demand ratio of the myocardium.

Adult↗
PubMed1978

Acute coronary occlusion with impending infarction as an angiographic complication relieved by a guide-wire recanalization.

In a 45 year old male patient with a history of previous inferior myocardial infarction and unstable angina pectoris, coronary angiography revealed two-vessel disease: a 60-70% lesion in the middle third of the LAD, and a 90% lesion in the middle third of the very large RCA. There was only a small akinetic segment in the posterobasal region of the left ventricle. During angiography total occlusion of the RCA occurred followed the clinical and electrocardiographic signs of impending inferior reinfarction. Recanalization of the occluded vessel was accomplished by using a guide-wire, which was passed through a Sones catheter, placed in the RCA. The patient's symptoms subsided and the electrocardiographic signs of acute ischemia reverted within eight minutes. Aortocoronary bypass surgery with revascularization of the LAD and RCA was performed within 3 hours after recanalization. Postoperatively there was no evidence of major tissue loss by enzyme or electrocardiographic criteria. Control angiography, performed on the ninth day postoperatively, revealed the graft to the RCA to be widely patent. Left ventricular function was unchanged. It is concluded, that the combined approach of early transluminal recanalization of the acutely occluded RCA followed by successful construction of a graft to this vessel, has averted necrosis of a major portion of the left ventricle. However, general use of this technique does not seem advisable at the present time.

Acute Disease↗
PubMed1978

[The influence of afterload on the normal and ischemic myocardium in the dog].

The influence of an instantaneous increase in afterload on the hemodynamics and regional myocardial function was studied in five anesthetized dogs before and after occlusion of the left anterior descending coronary artery. By inflation of an intaaortic balloon during single ejections, an instantaneous increase in afterload was obtained. From biplane cineventriculograms, the following parameters were calculated: left ventricular volumes (EDV, ESV), stroke volume (SV), ejection fraction (EF). Mean circumferential fiber shortening (V CF) was calculated in three ventricular diameters in the RAO projection. Simultaneously PLV, PLVED, PAo, and LV dp/dt were obtained. In the control ventriculograms, an increased afterload (delta PLV 16.4 +/- 8 mm Hg) caused only a minor decrease of SV (2.6 +/- 2.5 ml), EF (4.2 +/- 2.4%), and V CF (0.20 circ . s -1). After coronary occlusion (delta PLV 14.5 +/- 6.7 mm Hg),the reduction of SV (5.9 +/- 2.7 ml) and EF (8.2 +/- 2.6%) was more pronounced. This was caused mainly by a significant reduction of V CF in the center of ischemia (delta V CF -93%). For the evaluation of regional myocardial function by ventriculography, the marked influence of afterload in ischemic areas must be taken into consideration. This is of special interest in comparative ventriculograms, such as those before and after coronary bypass surgery.

Animals↗
PubMed1977

[Haemofiltration in the treatment of acute left heart failure in anuric patients (author's transl)].

Eight patients with acute left heart failure refractory to diuretics were treated by haemofiltration. Used conventionally the filtration membranes need a high pressure gradient. But the hollow-fibre kidney use in the last three patients required merely normal arterial venous pressure gradients. During an average heaemofiltration period of four hours 1000-2300 ml of plasma water were obtained. Pulmonary congestion improved in all patients; in five the arterial pressure returned to normal. Spontaneous diuresis was resumed in three. The clinical course was not influenced by haemofiltration in three instances. The advantages of haemofiltration are: reliable control of volume withdrawal, immediate effectiveness, technical simplicity, and absence of side effects.

Aged↗
PubMed1976

[Myocardial function of the right ventricle in coronary disease].

In 19 patients with healed myocardial infraction and normal right ventricular pressures, right and left ventricular volumes (biplane cineangio), ejection fractions and pressures were measured. Twelve of the patients had proximal severe stenosis of the right coronary artery (Group A), which was not diseased in seven patients (Group B). RV mean velocity of diameter shortening (VD) and LV mean velocity of circumferential fiber shortening Vcf) were calculated. Group A and B had similar RV systolic pressures (26.3 +/- 1.0 and 24.7 +/- 2.1 mm Hg) and LV hemodynamics (LVP: 127.5 +/- 5.9 and 122.1 +/- mm Hg, LVPED: 13.1 +/- 1.0 and 13.9 +/- 1.0 mm Hg, LVEF: 45.3 +/- 3.8 and 48.4 +/- 4.6%, Vcf: 0.768 +/- 0.114 and 0.861 +/- 0.123 circ/s). Only LVEDV was significantly higher in Group A (135.3 +/- 6.0 and 103.7 +/- 5.4 ml/m2). RVEDV (Group A: 131.4 +/- 4.5 and Group B: 87.9 +/- 4.8 ml/m2), RVEF (48.8 +/- 1.9 and 56.0 +/- 1.0%), RVPED (6.1 +/- 0.8 and 4.0 +/- 0.4 mm Hg) and VD (0.628 +/- 0.049 and 1.073 +/- 0.082 D/s) indicated significantly impaired RV function in Group A. It can be concluded that coronary artery disease of the right coronary causes significant functional impairment of the right ventricular myocardium.

Adult↗