Biomedical subjects

F Schwarz

Publications and source records attributed to F Schwarz.

At least 91 records · Page 5Linked to original sources

PubMed1986

[Determinants of long-term prognosis following prosthetic mitral valve replacement].

UNLABELLED: Data of 235 patients with chronic mitral valve disease (NYHA class III or IV) were analyzed retrospectively. Mitral valve replacement was performed in all patients between 1974 and 1983, 46 patients underwent additional tricuspid valve repair during the same operation. Preoperatively, right and left heart catheterization as well as coronary angiography were carried out in all patients. Operative mortality was 8%. For all patients 5 year survival rate was 76% and 10 year survival rate was 72%. Patients with pure mitral insufficiency had a poorer long-term prognosis than patients with mitral stenosis or patients with mixed mitral valve disease (5 year survival rate 54 versus 79%, p less than 0.0014). Patients with previous closed mitral commissurotomy had a poorer long-term prognosis than patients without previous surgery (5 year survival rate 62 versus 81%, p less than 0.0019). Age, NYHA class, associated tricuspid valve repair, pulmonary vascular resistance and mean right atrial pressure had no effect on survival. CONCLUSION: Long-term survival is generally good after mitral valve replacement, but pure mitral insufficiency and previous closed mitral commissurotomy are risk factors for long-term prognosis.

Cardiac Catheterization↗

PubMed1985

[Long-term prognosis of acute transmural myocardial infarct after intracoronary thrombolysis treatment].

Reperfusion of the infarct vessel by a combination of intravenous and intracoronary infusion of streptokinase succeeded in 66 of 120 patients with acute transmural infarction in whom the infusion had been started less than six hours after onset of symptoms. The recanalization attempt failed in 26, and 28 were treated conventionally. Size of the infarct was determined by 201Thallium scanning before and 48 hours after the acute treatment phase. Cox analysis indicated that successful recanalization had a significantly positive effect on the long-term prognosis compared with failed thrombolysis or conventional measures. The perfusion defect (as measured by 201Thallium scan) was identical in all three groups, but after successful recanalization with streptokinase it was significantly smaller than in the other two groups. The improved long-term prognosis is presumably due to a decrease in the size of the infarct.

Aged↗

PubMed1985

[Long-term results after local thrombolysis in acute massive pulmonary embolism].

Intrapulmonary arterial infusions of urokinase (mean 1724 IU/kg X h) and heparin (mean 17 IU/kg X h) were given to 7 patients with acute massive pulmonary embolism. Pulmonary angiography and pulmonary artery pressure measurements were performed before, during and 15 months after the drug infusion. During the acute phase, pulmonary artery pressures were recorded daily while urokinase and heparin were administered until the pressures had become normal (after a mean of 6 days). 15 months later right heart catheterization was undertaken before and after ergometric exercise as well as bilateral leg venography. Before treatment pulmonary angiography demonstrated massive vascular obstruction which regressed markedly during and after drug infusion. Treatment also led to normalization of previously elevated pulmonary artery pressures. In addition, pulmonary artery mean pressures and total pulmonary vascular resistance became normal both at rest and on exercise in 6 patients. All patients had signs of acute leg vein thrombosis before treatment, but 15 months later phlebography demonstrated normal findings in 4 and residual findings of previous thrombosis in 3. Local thrombolysis of acute massive pulmonary embolism is thus a highly successful form of treatment.

Adult↗

PubMed1985

Renal concentrating ability in obesity. Effect of modified fasting and the supplementation of T3, sodium chloride and carbohydrate.

The renal concentrating ability (RCA) was studied in 30 obese subjects before and after modified fasting (MF) and T3 supplementation, and during hypocaloric-carbohydrate refeeding. We also studied the effect of sodium supplementation on the RCA during MF. Modified fasting induced a low T3-high rT3 state ("sick euthyroid"). During T3-supplementation plasma T3 levels increased but were in the normal range for normal weight controls. Plasma sodium, potassium, and calcium remained within the normal range during all study periods. After MF (14 days) the mean maximal urinary osmolality was significantly lower compared to prefast values both after dehydration alone (706 +/- 12 mosm/kg H2O v 975 +/- 14, P less than 0.001) and after dehydration plus sc vasopressin administration (676 +/- 19 v 899 +/- 17, P less than 0.001). After 14 days MF followed by 14 days MF + T3-supplementation plasma urea, urinary urea excretion, and the creatinine clearance were significantly greater than after MF alone as was the RCA (764 +/- 15 v 652 +/- 25, P less than 0.002). Sodium chloride supplementation increased RCA (P less than 0.02) but no additive effect of T3 and sodium chloride supplementation was observed. Severe dietary salt restriction induced a significant decline in RCA (P less than 0.005). Refeeding with carbohydrate increased plasma T3 from 79.9 +/- 7.7 to 97 +/- 7.5 ng/100 mL (NS) and decreased plasma rT3 from 0.33 +/- 0.02 to 0.27 +/- 0.02 ng/mL, (P less than 0.02); no significant change in RCA was observed.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1985

Late pulmonary embolization of a retained pacemaker electrode fragment after attempted transatrial extraction.

Embolization of pacemaker electrode fragments into the pulmonary circulation is a rare complication following transvenous pacemaker implantation. One such case is reported here. In a 67-year-old patient, a battery pocket infection developed after transvenous pacemaker implantation and subsequent surgical revision. After removal of the pacemaker and ventricular pacing lead, the atrial lead broke within the superior vena cava when prolonged traction was applied after frustrating attempts to extract the electrode. Attempts to extract the fragment transvenously using endoscopic forceps were unsuccessful. Due to firm fixation of the electrode by extensive fibrous scar tissue in the atrial wall, a further attempt to remove the retained electrode fragment by atriotomy also failed. On the first postoperative day, the fragment migrated to the left pulmonary artery, from where it was successfully extracted by means of a Dormier basket.

Aged↗

PubMed1985

Bromocriptine therapy in acromegaly: effects on plasma GH levels, somatomedin-C levels and clinical activity.

Thirty-one patients with active acromegaly were treated with 10-20 mg bromocriptine daily for a period of 6-9 months. The clinical response was evaluated both by a subjective 'score of symptoms', and by a combined subjective and objective 'clinical and metabolic improvement score' (c-m score). The biochemical response was evaluated both by measurement of the mean of four plasma growth hormone (GH) determinations during the day and by measurement of plasma somatomedin-C (Sm-C) concentration. The clinical response as assessed by both methods showed a better correlation with changes in plasma GH levels (respectively r = 0.33; r = 0.50) than with changes in Sm-C levels (r = 0.20; r = 0.36). The study confirms that in some patients clinical improvement is not accompanied by a decrease of plasma GH concentration. However, it is not possible to identify a subgroup of patients who showed clinical improvement with a decrease of Sm-C levels, but whose plasma GH levels remained constant. It is concluded that measurement of plasma GH levels still appears to be the most useful biochemical assessment of disease activity in bromocriptine-treated acromegaly.

Acromegaly↗

PubMed1985

Sustained improvement of pulmonary hemodynamics in patients at rest and during exercise after thrombolytic treatment of massive pulmonary embolism.

This study assessed the long-term effects of thrombolytic treatment in patients with acute massive pulmonary embolism (PE). Seven patients with PE that followed deep-vein thrombosis underwent pulmonary angiography and pressure measurements before and 6 +/- 3 days (mean +/- SD) and 15 +/- 4 months after treatment with intrapulmonary infusions of urokinase (average dose 1724 U/kg X hr) and heparin (average dose 17 U/kg X hr). Treatment was guided by daily measurements of pulmonary arterial (PA) pressure and was continued until PA pressure had normalized (average of 6 days). Late after treatment patients returned for pulmonary angiographic examination, right heart catheterization at rest and during bicycle exercise, and phlebography of the deep veins of both legs. Pulmonary angiograms showed massive obstruction before therapy (Walsh index 15 +/- 2 points of a maximum of 18 points), which was improved 6 days (3 +/- 3 points) and 15 months (1 +/- 2 points) after therapy. Mean PA pressure declined from 37 +/- 9 to 13 +/- 3 mm Hg after 6 days and to 15 +/- 3 mm Hg after 15 months. No recurrence of PE was observed. In six of seven patients at rest and during bicycle exercise (up to 100 W) in the supine position mean PA pressure and total pulmonary resistance remained within normal limits. Over the short term all patients showed clinical signs of deep-vein thrombosis; 15 months later four patients had normal deep veins, but three patients had still phlebographic signs of old thrombosis.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1985

Changes of molecular forms of growth hormone in bromocriptine treated acromegaly in relation to changes of somatomedin-C and clinical response.

Eleven patients with active acromegaly were treated with 10-20 mg bromocriptine daily for a period of 6-9 months. The clinical response was evaluated by a 'clinical and metabolic improvement score'. The biochemical response was evaluated by measurement of both the mean plasma growth hormone (GH) level during the day and the somatomedin-C (Sm-C) concentration. Before and at the end of the treatment period plasma samples were fractionated by Sephadex G-100 chromatography in order to study the effects of chronic bromocriptine treatment on the concentrations of total GH and its different molecular forms. The main observations may be summarized as follows: Three immunoreactive components were observed on Sephadex chromatography corresponding to molecular weight above 100 000 (big-big GH), 40 000-60 000 (big GH) and 20 000-22 000 (little GH). Bromocriptine treatment induced preferentially a reduction of little GH. There was a very good correlation between the decrease of little GH and total GH, and both were significantly correlated with the clinical response. The correlation between the decrease of Sm-C values and that of little and total GH as well as between the decrease of Sm-C and the clinical response was poor. It is concluded that a) measurement of little GH is not superior to the determination of total GH in the assessment of disease activity of bromocriptine treated acromegalic patients; b) both methods are superior to the measurement of plasma Sm-C levels; c) clinical response out of proportion ot the fall of total GH which can be explained by a preferential reduction of little GH, has not been observed in our investigations.

Acromegaly↗

PubMed1985

Metabolic responses during modified fasting and refeeding. The role of sympathetic nervous system activity and thyroid hormones.

Thyroid hormones, sympatho-adrenomedullary activity and metabolic responses have been studied in eight healthy obese subjects during modified fasting (0.8 MJ, 200 kcal/d) for 14 d, followed by hypocaloric-carbohydrate refeeding (2.4 MJ, 600 kcal/d) for 3 d. In the week preceding modified fasting, the subjects received a 7.2 MJ (1800 kcal) diet daily containing 20 mmol sodium, in order to distinguish the effects of salt depletion from those of energy restriction. Sodium (20 mmol/d) and potassium (80 mmol/d) were kept constant throughout the study. During modified fasting a low T3-high rT3 state developed; concomitantly a marked decrease in sympatho-adrenomedullary activity (assessed by 24-h urinary excretion of catecholamines) was observed. Upon refeeding plasma T3 increased and plasma rT3 decreased, but not completely to pre-fast values. Upon refeeding urinary catecholamine excretion markedly increased. A strong inverse relationship was found between the marked decrement of both thermogenic hormones and the catabolism of protein. No correlation between these parameters was found during brief refeeding. The observed decline of both thermogenic hormones may represent an adaptation to protect tissues from the catabolic effect of these substances during severe energy deficiency.

Adolescent↗

PubMed1985

[Long-term prognosis of drug and surgery treated patients with acquired aortic valve diseases: survival statistics and multivariate Cox regression analysis].

Data of 417 patients with advanced chronic aortic valve disease were retrospectively analyzed using a life table and Cox regression analysis. Aortic valve replacement was recommended to all patients based on clinical and hemodynamic findings. While most patients underwent prosthetic aortic valve replacement (n = 349), a minority of patients was treated medically (n = 68). Prognosis was better (p less than 0.01 in the Cox model) in surgically treated as compared to medically treated patients with aortic stenosis (4-year survival rate 82 versus 44%). In patients with aortic insufficiency no significant difference of long-term prognosis was found between surgically and medically treated patients.

Anti-Bacterial Agents↗

PubMed1985

[Aortic ring abscess following bacterial endocarditis of the aortic valve and aortic valve replacement].

Valve replacement was performed in a 30-year-old male patient with acute aortic insufficiency due to bacterial endocarditis. During a routine examination three months later, an aortic ring abscess was found by echocardiography. In the following night, the patient was readmitted with acute anterior myocardial infarction. Coronary angiography showed a compression of the left coronary artery by the large ring abscess of the aortic valve. 48 hours after surgical revision of the aortic valve prosthesis and the ring abscess, the patient died due to pump failure.

Abscess↗

PubMed1984

Effect of successful thrombolytic therapy on right ventricular function in acute inferior wall myocardial infarction.

In 19 patients undergoing intracoronary fibrinolytic therapy for acute myocardial infarction, the site of coronary obstruction was in the proximal right coronary artery. Time between onset of symptoms and hospitalization was less than 4 hours. These patients were studied prospectively by radionuclide techniques immediately after admission, 48 hours and 4 weeks after AMI. Right and left ventricular (RV and LV) ejection fractions (EF) were calculated from gated blood pool scintigrams and the size of the LV perfusion defect was assessed by thallium-201 scintigraphy. Before the intervention, RV performance was significantly lower (RVEF 29 +/- 8%) than normal (53 +/- 7%). The size of the LV perfusion defect was relatively small (less than 25% of LV circumference), and as a consequence, LV pump function was only marginally impaired (LVEF 54 +/- 11%). Recanalization of the infarct artery was achieved in 12 patients (group A); in 7 patients the infarct artery remained occluded (group B). Early after the intervention (48 hours), RV performance in group A recovered significantly (RVEF: 30 +/- 9% vs 39 +/- 7%, p less than 0.01), and further improvement was noted at 4 weeks (RVEF 43 +/- 5%, p less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1984

Necropsy evaluation in seven patients with evolving acute myocardial infarction treated with thrombolytic therapy.

Systemic and intracoronary streptokinase application may recanalize a coronary artery occluded by a thrombus in patients with acute myocardial infarction (MI). However, thrombolysis fails in a number of patients for unknown reasons. The coronary and myocardial histologic characteristics were studied in 3 patients in whom recanalization was successful without subsequent reocclusion, and in 4 patients in whom recanalization was unsuccessful. All patients died within 4 weeks after the acute intervention. Serial sections from the angiographically localized occlusive site of the infarct vessel, and transverse slices of the heart stained with nitroblue tetrazolium for delineation of MI, were examined by light microscopy. Successfully recanalized arteries were patent at necropsy and showed obstructive fibrous atherosclerotic plaques. Among patients in whom recanalization was unsuccessful, 1 patient had occlusions from nonatherosclerotic intramural hemorrhage and 1 from persisting long, mixed old and fresh thrombus, and 2 patients had high-grade obstructions from ruptured atherosclerotic plaques with intimal hemorrhage and residual clot. Reperfused infarct tissue consisted predominantly of contraction band necroses, whereas MIs without reperfusion showed coagulation necroses of the muscle fibers. The results suggest that the success of recanalization depends, in part, on the morphologic features of the coronary occlusion, and that reperfusion after successful thrombolysis may lead to a different pattern of muscle fiber necrosis in the irreversibly injured infarct areas.

Adult↗

PubMed1984

Estimation of left ventricular myocardial function by the ejection fraction in isolated, chronic, pure aortic regurgitation.

In patients with aortic regurgitation (AR), the left ventricular (LV) ejection fraction (EF) may not adequately reflect depressions of myocardial contractility due to decreased aortic impedance. The sensitivity of end-systolic pressure-volume relations and stress-volume relations in detecting myocardial depression in patients with AR was studied. In 12 patients with normal valvular function but with varying LV function (due to coronary heart disease in 9 patients and dilated cardiomyopathy in 3 patients) (group 1), and in 8 patients with AR (group 2), LV angiography was performed before and after sublingual application of isosorbide dinitrate. Heart rate was kept constant by right atrial pacing. In group 1, the slope k of the end-systolic pressure-volume relation was to EF at rest: k = 0.091.e0.051 EF; r = 0.88. In AR, this relation was shifted significantly to the right: k = 0.019.e0.066 EF; r = 0.92. This shift persisted when the end-systolic stress-volume relation instead of the end-systolic pressure-volume relation was calculated. Thus, in patients with AR the end-systolic pressure-volume relation is flatter than that in patients with intact valvular function at a given EF. The same is true for the end-systolic stress-volume relation. The data indicate that EF overestimates myocardial contractility in AR compared with end-systolic pressure-volume or stress-volume relations. This overestimation is probably a result of decreased aortic impedance in AR.

Adult↗

PubMed1984

Ventricular arrhythmias before and late after aortic valve replacement.

The influence of aortic valve replacement on the incidence of ventricular arrhythmias was studied by 24-hour Holter electrocardiographic monitoring in 45 patients immediately before and 14 +/- 7 months after operation. Ventricular arrhythmias were graded according to the Lown criteria. Preoperative left ventricular (LV) ejection fraction (EF) was determined by angiography and postoperative LVEF by gated blood pool scintigraphy. Repetitive ventricular arrhythmias (Lown grade 4A/B) were associated with a reduced LVEF (less than 55%) before and after operation. In 24 patients with preoperative normal LVEF (greater than or equal to 55%) (group A), mean LVEF remained unchanged after operation (72% vs 71%). Pre- and postoperative ventricular premature complex (VPC) frequency (45 +/- 99 vs 39 +/- 94 VPC/24 hours) and grade (1.3 vs 1.4) were not significantly different. However, in 17 patients with preoperative impaired LVEF (less than 55%) (group B, LVEF preoperatively 40 +/- 8%) and marked postoperative improvement (greater than 10%) (LVEF postoperatively 64 +/- 7%), mean VPC frequency decreased from 536 to 69 VPCs/24 hours and mean VPC grade was reduced from 3.8 to 1.5. Complex VPCs were found preoperatively in all 17 patients of group B, but in only 5 patients after operation. Four patients had a reduced LVEF preoperatively and it did not improve postoperatively (group C). Postoperative Holter monitoring detected ventricular tachycardia in all 4 patients. This study indicates that repetitive VPCs are infrequent in patients with normal LVEF before and late after aortic valve replacement. In patients with impaired LVEF and complex VPCs preoperatively, the postoperative improvement of LV function is usually accompanied by a reduction of frequent and complex VPCs.

Adolescent↗

PubMed1984

Thrombolysis in acute myocardial infarction: effect of intravenous followed by intracoronary streptokinase application on estimates of infarct size.

The effect of pretreatment with intravenous infusion of streptokinase (SK) (16,700 U/min for 90 minutes), started after diagnosis and followed by intracoronary application (2000 U/min) (protocol 1), was assessed retrospectively in 55 consecutive patients with acute transmural myocardial infarction (MI). Another 46 patients with acute MI treated previously by intracoronary thrombolysis served as control subjects (protocol 2). Reperfusion at first coronary injection was observed after pretreatment in 25 patients (45%), but in no control patient (p less than 0.001). Fifteen patients with successful pretreatment (group A), 20 patients with successful treatment according to protocol 2 (group B) and 9 patients with unsuccessful thrombolysis (group C) were restudied after 4 weeks. Data from patients with reinfarction, coronary bypass surgery or percutaneous transluminal coronary angioplasty before restudy were excluded. Thallium-201 scintigraphy was performed before and 24 hours after treatment, serum creatine kinase activity was measured every 8 hours for 3 days and regional ejection fraction (EF) of acute MI was determined before and 4 weeks after treatment. The scintigraphic, enzymatic and hemodynamic data before treatment indicated severe and comparable ischemia among the 3 groups. The thallium-201 perfusion defect decreased in group A (from 41 to 21%, p less than 0.01) and in group B (from 38 to 26%, p less than 0.01), but did not change in group C (from 37 to 31%, difference not significant). Peak serum creatine kinase levels normalized by the perfusion area of acute MI was 20, 33 and 58 U/liter unit in groups A, B and C. The mean values of groups A and C were significantly different (p less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1984

[Local thrombolysis with urokinase in acute massive pulmonary embolism].

Urokinase (average 1670 IU/kg X h) and heparin (average 17 IU/kg X h) was infused over several days into the main pulmonary artery of 12 patients with acute massive pulmonary embolism, after diagnostic pulmonary angiography. Pulmonary artery pressures and blood clotting values were serially recorded. There was convincing improvement in the clinical condition of all patients: none died or had a recurrence of embolism. The heart rate and pulmonary vascular obstruction decreased, mean pulmonary artery pressure fell and arterial pO2 rose. There were other, also statistically significant, changes in a decrease of fibrinogen, rise in thrombin time and decrease in haemoglobin concentration. Pulmonary artery pressure after 24 hours had fallen slightly, after 5.8 days significantly. In two patients a haemoglobin fall of more than 3 g/dl required blood transfusion. The findings indicate that after massive pulmonary embolism local continuous infusion of urokinase can, after 5-6 days, normalize pulmonary haemodynamics; the pulmonary angiogram shows almost complete disappearance of the pulmonary vascular obstruction.

Acute Disease↗

PubMed1984

Plasma growth hormone suppressive effect of bromocriptine in acromegaly. Evaluation by plasma GH day profiles and plasma GH concentrations during oral glucose tolerance tests.

In most studies reporting favourable results of chronic bromocriptine treatment in acromegaly, plasma GH levels are measured at fixed intervals during the day. Negative results are reported in one major study measuring plasma GH levels during oral glucose tolerance tests (Lindholm et al., 1981). This study does not mention the time interval between the last dose of bromocriptine and the performance of an OGTT, but due to the short duration of action of bromocriptine this may be critical. Therefore, in the present report the plasma GH suppressive effect of bromocriptine in acromegaly is studied using plasma GH day-profiles as well as OGTT's during continued bromocriptine administration and OGTT's at two different time intervals after the last dose of bromocriptine. Twelve patients with clinically active acromegaly were treated with 10-20 mg bromocriptine for 6-9 months. After 6-9 months during continued bromocriptine administration the plasma GH suppressive effect of bromocriptine was evaluated by the mean of four plasma GH determinations during the day and by the mean of seven plasma determinations during oral glucose tolerance tests (OGTT's) performed 1 h, 10 h and 34 h after the last dose. The percentage decrease of the mean plasma GH level during the day induced by chronic bromocriptine treatment showed a good correlation (r = 0.86, P less than 0.001) with the percentage decrease of the mean plasma GH level during OGTT, if the post-treatment test was carried out one hour after the last dose of bromocriptine.(ABSTRACT TRUNCATED AT 250 WORDS)

Acromegaly↗